Educational objective: Review clinical presentation of primary HIV infection.
Primary HIV infection is symptomatic in 50-90% of patients but is frequently unrecognized because of the nonspecific symptoms.
Following are symptoms identified as part of the presentation of the primary HIV infection:
Another sign that was consistently seen is weight loss (5 kg in average). Hematuria is, however, not part of the presenting picture of primary HIV infection.
Educational objective: Review indications for 3-days antibiotic therapy for urinary tract infection.
Using a single large dose of antibiotics for 3 days in a young woman with an uncomplicated urinary tract infection is appropriate. However, a short course of therapy is contraindicated in diabetics, men, pregnancy, urologic abnormalities, immunosuppression diseases, and older age groups.
Educational objective: Understand epidemiology of HIV epidemic.
Mode of transmission for HIV infection for U.S. adult and adolescent population (2004).
It is important to note that in the developing world the most common mode of transmission is heterosexual contact.
A 32-year-old homosexual man was seen in the office for whitish plaques inside his mouth. On examination typical lesions of the oral candidiasis were found on buccal mucosa. In addition he reported having occasional fever and diarrhea.
HIV serologic testing was ordered and came back positive. In which stage of HIV infection this patient is most likely to be?
Educational objective: Review natural history of HIV infection.
The HIV-1 infection is divided in the following stages:
Early symptomatic HIV infection is characterized by the following conditions (all of which may occur in association with other disorders, but are more frequent or severe with HIV infection):
Educational objective: Understand natural history of HIV infection.
The average life expectancy for HIV-infected patients in the absence of treatment is about 10 years. The rate of progression may depend on the mode of transmission (faster for transfusion mode than for intravenous drug users or homosexual men). In addition it appears that age at infection is also a major determinant of progression. In one study, time from seroconversion to AIDS was 15 years for patients infected in age group 16-24 years and 6 years for those infected after age of 35.
Characteristics of the virus itself may also influence the rate of progression (a cohort of patients from Australia – 1 blood donor and 8 recipients – have very slow progression and virus has deletion of part of genetic material).
Educational objective: Review common causes of urinary tract infections.
Approximately 70% of all urinary tract infections are caused by E. coli. About 30% of all E. coli related urinary tract infections are resistant to ampicillin. Approximately 25% of all urinary tract infections are due to staphylococcus saprophyticus. Chlamydia species account for 20% of urinary tract infections, and other Enterobacteriaceae account for the rest.
Educational objective: Understand significance of CD-4 cell count and HIV-RNA determination in HIV patients.
Two important laboratory determinants of the rate of the progression and ultimate prognosis in patients with HIV infection are the CD-4 cell count and the viral load (HIV-1 RNA quantitation). Rate of the CD-4 cell count decline is another important prognostic factor. Prognosis is worse in patients with lower CD-4 cell count, a faster rate of CD-4 count decline, and higher viral burden.
The risk of progressing to AIDS is lowest for patients with an undetectable viral load and A CD-4 count of more than 500 mm3 (0% five year progression to AIDS in one study) and is much higher in patients with viral loads over 10,000 copies/ml and CD-4 count below 200 mm3 (81% in five years in the same study).
Educational objective: Review indications for PCP prophylaxis.
PCP remains the leading initial AIDS-defining illness and an important cause of death in patients with AIDS. Widespread use of prophylaxis has diminished incidence of PCP.
Risk factors for the development of PCP include (and indicate need for prophylaxis):
Prophylaxis reduces both the incidence of the PCP infections in patients and mortality in patients who develop PCP. It was repeatedly shown that prophylaxis for PCP is cost-effective.
Educational objective: Review options for PCP prophylaxis.
Several different regimens have established efficacy of PCP prophylaxis. Trimethoprim-sulfamethoxazole has a number of advantages when used for PCP prophylaxis. It is active not only against PCP, but also toxoplasma gondii, isospora, salmonella, listeria, nocardia, legionella, haemophilus influenzae, streptococcus pneumoniae, staphylococcus aureus, and many gram-negative bacilli. The major risk factor for the prophylaxis failure is a CD-4 count below 50 mm3. Aerosolized pentamidine, dapsone and atovaquone are also efficient in preventing PCP, but are second line drugs and used when there is allergy to TMP-SMX or therapy cannot be tolerated due to side effects (25-50% of cases – fever, rash, bone marrow suppression, and transaminases elevations).
Clindamycin with pyrimethamine appears not to be effective and is often complicated by diarrhea.
Educational objective: Review indications for fiberoptic bronchoscopy and high resolution CT scanning.
Fiberoptic bronchoscopy and high resolution CT (HRCT) are, in many ways, complementary to each other. Both of those procedures have advantages in certain clinical situations. In one study HRCT demonstrated all tumors seen on bronchoscopy as well as several which were beyond bronchoscopic range. On the other hand, HRCT could not detect bronchitis or subtle mucosal abnormalities that could be seen on bronchoscopy. In one study HRCT was particularly useful in diagnosing bronchiectasis and aspergillomas, while bronchoscopy was diagnostic of bronchitis and mucosal lesions such as Kaposi’s sarcoma. The patient in question is at high risk for pulmonary carcinoma; as of today, the procedures are considered complementary in this setting.
Educational objective: Review therapeutic options for CMV retinitis in HIV infected patients.
The major drugs that are used for treatment of cytomegalovirus retinitis are intravenous ganciclovir and foscarnet, oral ganciclovir, intraocular ganciclovir, and intravenous cidofovir. Ganciclovir and foscarnet have equivalent efficacy against the retinitis. Major side effects of the ganciclovir are neutropenia and thrombocytopenia (limiting use in up to 16% of patients). Ganciclovir should not be given with absolute neutropenia of less than 500 mm3 and thrombocytopenia 25, 000 mm3.
Foscarnet increases serum creatinine concentration (due to acute tubular necrosis) and may produce symptoms of hypocalcemia during drug infusion because of chelation of serum ionized calcium (and magnesium). These side effects have been dose-limiting in up to 20% of patients.
A 34-year-old patient with HIV infection who is taking highly effective antiretroviral therapy very compliantly was seen for routine control. The CD-4 cell count and viral load were ordered and came back as 189 cells/mm3 and 5000 copies/ml. His previous measurements of CD-4 cell counts were as follows – 403 cells/mm3, 350 cells/mm3, 370 cells/mm3 and 385 cells/mm3 starting with earliest to the latest. His viral load results were (in the same order): 30,000 copies/ml, 23,000 copies/ml, 11,000 copies/ml and 7000 copies/ml.
Which of the following is the best course of action in this case?
Educational objective: Understand variability and significance of changes in CD-4 cell count measurements.
The CD-4 cell count is measured by flow-cytometry and a number of factors other than HIV infection influence CD-4 cell count. Those factors include seasonal and diurnal variations, some viral infections, corticosteroids, tuberculosis, and analytic variation.
Awareness of the causes of fluctuations in the CD-4 cell count is particularly important for both the care provider and patient. Test results that present “milestones” for therapeutic decisions or classification of a patient as having AIDS based on CD-4 cell count below 200 cells/mm3 should be repeated immediately. This should especially be done if the values do not correlate well with prior results (like in this patient). The degree of variability was demonstrated in a multicenter AIDS cohort study where 95% confidence ranges were 297-841 mm3 for a true content of 500 mm3 and 118-337 mm3 for true content of 200 mm3.
Educational objective: Understand interpretation of changes in HIV-RNA (viral load) measurements in HIV infected patients.
All three viral load assays have a low intra-assay variation on repeated testing of a single specimen (between 0.12-0.2 log10). On the other hand, in clinically stable patients (with no change in antiretroviral therapy), the biologic variability of viral RNA measurements is about 0.3 log10. Having those facts in mind, changes in viral count of at least 0.5 log10 (or threefold) usually reflect biologically relevant changes in the level of viral replication. It is important not to over-interpret small increases or decreases in viral load.
Educational objective: Understand risk of HIV transmission in perinatal period.
It is estimated that that about 1600 infants with HIV infection are born in the world every day. Overall, in the child population, the main mode of transmission is perinatal acquisition from an HIV infected mother. In cases of pregnant women with CD-4 counts of more than 200 cells/mm3 and no or minimal symptoms, and who did not receive any antiretroviral treatment doing their pregnancy, the transmission of the infection to the infants occurs in approximately 25 percent of the cases.
Educational objective: Understand the risk for HIV transmission after parenteral and mucosal and skin exposures.
The risk of becoming infected with HIV after exposure to body fluids from an HIV-infected patient is low. From the review of 23 studies of needle stick injuries, mucosal and skin exposures to an HIV-infected source, the following data have emerged:
The majority of the health workers affected by HIV exposure (and infection) are nurses and laboratory technicians. There are no documented seroconversions with exposure to a suture needle.
Host factors that predispose to salmonella infection are:
Impaired cell-mediated immunity (AIDS, corticosteroids use, malignancy.)
Impaired phagocytic function (hemoglobinopathies,chronic granulomatous disease, malaria, histoplasmosis, schistosomiasis)
Extremes of age (neonates & elderly)
Decreased gastric acidity (antacids, H2 blockers, proton pump inhibitors, achlorhydria)
Altered intestinal function (inflammatory bowel disease, prior antibiotic therapy).
Hepatitis: Monitoring of AST, limiting alcohol intake, monitoring for hepatitis symptoms and stopping the drug at first sign of hepatitis.
Peripheral neuritis: Vitamin B6 supplementation.
Optic neuritis: Vitamin B6 supplementation.
Seizures: Vitamin B6 supplementation
Rash: Observation of the patient.
Liver dysfunction: Monitor AST, limit alcohol, monitor for hepatitis symptoms.
Flulike syndrome: Administered twice-weekly, limit dose to 10 mg/kg for adults.
Red-orange urine: Reassurance.
Drug interactions: Monitor levels, especially with digoxin, contraceptives and anticoagulants. Avoid use with protease inhibitors.
Hepatitis: Monitor AST. Limit dose to 15-30 mg/kg/day.
Hyperuricemia: Monitor uric acid level only in cases of gout or renal failure.
Optic neuritis: monitor visual acuity and green-red color vision monthly. Stop drug on the first change in vision. Limit dose to 15 mg/kg/day.
Ototoxicity & Nephrotoxicity: Limit dose and duration of therapy as much as possible – avoid daily therapy in patients older than 50 years old. Monitor BUN and serum creatinine levels and possibly perform audiometry before and as needed during the therapy. Monitor for tinnitus, dizziness, vertigo and hearing loss. Measure serum drug levels. Stop drug on first sign of adverse effect.
TSS is a rare condition (reported incidence in menstruating women is 1:100 000). It is caused by any of several related toxic exoproteins produced by Staph. aureus. TSST-1 is the toxin most frequently implicated and enterotoxin B the second most frequent. For TSS to develop individuals need to be infected or colonized with toxigenic Staph. aureus and lack protective level of the antibody to the toxin made by that strain.
TSS is characterized by fever, rash, hypotension, involvement of at least three major organ systems, desquamation 1-2 weeks after onset of the illness (typically palms and soles), and lack of evidence for alternative diagnoses (Rocky Mountain spotted fever, leptospirosis, rubeola, etc.).
Predisposing factors are use of the barrier method of contraception, tampons, period of puerperium, septic abortion, nonobstetric gynecologic surgery, thermal burns, insect bites, varicella lesions and surgical wounds.
Within the first 6 weeks after transplantation, most patients who are seropositive for HSV – 1 excrete the virus in the oropharynx. Because of the relation of the ability to cultivate the virus and severity of the mucositis, many clinicians administer prophylactic acyclovir to seropositive bone marrow transplant patients. Both esophagitis (HSV – 1) and anogenital (HSV – 2) disease may be prevented by acyclovir prophylaxis. Cytomegalovirus virus infection usually has onset between 30 – 90 days after BMT and may cause interstitial pneumonia, bone marrow suppression or graft failure.
Candida infection has relatively slower onset, usually shows some whitish exudates on the mucosa, and also more often causes lesions in the oral cavity.
Peptic ulcer disease is not a feature of the esophageal pathology in bone marrow transplant patients.
For once-daily gentamicin therapy one needs to determine GFR for initial dosing regimen. According to accepted protocol, creatinine clearance and dosing are as follows:
Initial dose is calculated based upon patient’s actual body weight unless patient is overweight (>120% of ideal body weight - IBW).
Adjustment formula: Adjusted weight = IBW + 0.4 (actual wt – IBW)
A single serum sample should be obtained 6-14 h after the first dose. The level is then compared with a nomogram to determine when the next dose should be given. If the level indicates that a dose should be given less frequently than every 48 h, daily serum levels should be obtained to guide timing of the next dose.
Serum creatinine levels should be followed every 48-72 hours or more often if multiple nephrotoxic risk factors exist, ie. preexisting renal insufficiency, advanced age, dehydration/hypovolemia, liver disease or other nephrotoxins.
A repeat gentamicin serum level should be obtained every 96 hours during the therapy, or with significant reduction in the creatinine clearance.
The type of infecting organism as a cause of infectious arthritis varies with the age of the patient and predisposing factors.
An 18-year-old male presented with fever, pain and swelling of the right knee of 2 days' duration. He suffers from sickle cell disease. His knee is red, swollen, warm and tender on palpation and his range of motion is limited. Knee arthrocentesis is performed and Gram-stain is obtained which reveals large numbers of gram-negative bacilli.
What is the appropriate initial IV antibiotic therapy?
Initial therapy of the infectious arthritis depends upon the findings on gram-stain of the synovial fluid.
Gram-negative cocci:
In an adult consider N. gonorrhoeae arthritis and treat with ceftriaxone. In young children consider H. influenzae and treat with ampicillin (cefuroxime or chloramphenicol if allergic to penicillin).
Gram-positive cocci:
Consider Staph. aureus and treat with oxacillin or nafcillin (Vancomycin or cefazolin in penicillin- allergic patients).
Gram-negative bacilli:
Consider pseudomonas or (especially in SCD patients) E. coli and treat with aminoglycoside plus mezlocillin or piperacillin or amynoglycoside plus antipseudomonal cephalosporin (ceftazidime).
Inconclusive Gram-stain:
Treat according to presumed organism based on age and any risk factors (consider also Lyme disease).
In patients with PID who require outpatient therapy the CDC recommends a combination of oral ofloxacin (400 mg bid) and metronidazole (500 mg bid) for 14 days. An alternative is a single dose of ceftriaxone (250 mg IM) or cefoxitin (2 g IM + probenecid 1 g PO) followed by doxycycline (100 mg PO bid) for 14 days. The combination of amoxicillin-clavulanate and doxycycline also may be used.
Azithromycin (1g PO) and amoxicillin-clavulanate (875 mg PO) once followed with amoxicillin-clavulanate (875 mg PO bid) for 7-10 days are other recommended regimens.
Mild symptoms, including fatigue and malaise, are common in patients with chronic persistent hepatitis. Each of the other listed findings is more consistent with a diagnosis of chronic active hepatitis than chronic persistent hepatitis.
The rise in the incidence of hepatitis B has caused the Center for Disease Control and Prevention to recommend immunization of all infants against hepatitis B. The recommended injection site is the deltoid muscle in adults and anterolateral thigh muscle in infants and neonates.
Vaccine nonresponders will probably fail to respond to repeated vaccine course. Although hepatitis vaccination is useless in hepatitis B virus carriers, there are no adverse effects in this group of patients. The need for booster vaccination in patients in whom antibody level declines with time has not yet been determined.
Approximately 95% of patients with acute viral hepatitis will have change in urine color (dark urine). Common symptoms include fatigue, anorexia, nausea, itching, diarrhea, drowsiness, arthralgias and fever. These other symptoms are present in about 50% of patients suffering from acute viral hepatitis or less.
The bacteriology data of otitis media in children revealed that streptococcus pneumoniae is the most common bacterial pathogen isolated from infected middle ear (30%). Nontypable haemophilus influenzae and moraxella catarrhalis are isolated in 15-20% of patients. Group A streptococcus isolation varies with season and is highest in winter when 10% of isolates harbor this pathogen (5% overall). In studies of adult patients similar bacteriology is found.
Antibiotic treatment for acute otitis media may be withheld after carefully evaluating the patient for risk of complications. Patients with the following clinical features are at lower risk for complications:
Children over the age of two years Nontoxic clinical appearance Normal host defenses Patient likely to comply with follow-up treatment
Antibiotics should be used in any patient who does not fulfill all four of these criteria. If antibiotic therapy is not initiated, the patient should be reassessed in 42-72 hours and treatment should be started if there is no clinical improvement.
Prevention of acute otitis media is dependent upon changing environmental predisposing factors such as bottle feeding, tobacco smoke, and large day care centers. Chemoprophylaxis with amoxicillin or sulfisoxazole is often used during the winter months in the otitis prone child.
Antimicrobial prophylaxis does not appear to be effective if given promptly after the onset of symptoms of an upper respiratory infection in young children.
A 48-year-old man presents in the office with right ear pain and diminished hearing. The symptoms started after swimming at the community pool. The patient has type II diabetes mellitus and is being treated with an oral hypoglycemic agent. The patient is afebrile. He has pain on tragus manipulation during the otoscopic examination. The external ear canal is lined with a whitish material that prevents visualization of the tympanic membrane. There is no cervical lymphadenopathy.
What is the best management of this patient?
The presence of a white, cheesy, or mucous material suggests external otitis. The pain and tenderness of the ear on manipulation are common on physical examination. This patient is also a diabetic, which increases the risk for infection. Therefore, this patient should be treated with a topical antibiotic. Lavage or instrumentation of the ear as well as use of parenteral antibiotics or topical cerumenolytic agents is contraindicated in the management of external otitis.
External otitis must be differentiated from malignant otitis in a diabetic patient due to markedly different approach and potentially fatal complications of the later condition.
The most common presenting symptoms and signs of malignant otitis are severe unrelenting otalgia and otorrhea. The degree of drainage varies from copious, foul-smelling, greenish exudate to minimal accumulation of moisture. The mainstay of therapy for malignant otitis is a systemic antipseudomonal antibiotic for 4 to 8 weeks.
A 32-year old female is about to undergo tooth extraction. She is known to have mitral valve prolapse. On physical examination no murmur can be heard. Echocardiogram shows a bulging of the anterior and posterior leaflet in systole.
Prior to tooth extraction, which of the following preventive antibiotic regimens should cover this patient?
Educational Objective: Review the indications for endocarditis prophylaxis.
Antibiotic prophylaxis for infective endocarditis when undergoing dental, GI, or GU procedures is only indicated in patients with MVP who have a systolic murmur and/or echocardiographic evidence of mitral regurgitation.
Cefoxitin is indicated for certain GI operations for prevention of infection in the operative site.
Amoxicillin, erythromycin and clindamycin are all acceptable alternatives for endocarditis prophylaxis in patients with MVP if necessary.
An 81-year-old female with profound dementia has a grade-4 decubitus ulcer over the left trochanteric region that is not healing despite aggressive local care, muscle flap placement, and empiric antibiotic therapy.
Which is the best method to establish diagnosis of osteomyelitis in this patient?
Educational objective: Review diagnostic modalities for osteomyelitis.
Bone biopsy of the underlying bone is the most reliable method of establishing the diagnosis of osteomyelitis in cases of the decubitus ulcer resistant to therapy. Three-phase bone scintigraphy is often used to diagnose bone involvement in infections, but in this case may not clearly establish diagnosis as pressure can produce heterotopic bone formation. This will then lead to scintigraphic and radiographic changes that falsely resemble osteomyelitis. Surface culture of the ulcer or the bone exposed in the ulcer can reflect surface contamination and often does not correlate with the cause of the bony infection. The clinical picture of osteomyelitis is not specific enough to allow diagnosis.
A 33-year-old male patient with HIV infection was seen for a routine follow up. In the interim he was feeling fine and taking his highly effective antiretroviral therapy compliantly. He had one episode of herpes simplex infection on his lips about two weeks ago, but this resolved without difficulties and without therapy. He only took a couple of extra strength acetaminophen tablets (500 mg each) for one episode of headache during the last 4 weeks. Now he feels completely healthy. Physical examination was all within normal limits. Laboratory results revealed virtually unchanged CD-4 cell count and fivefold increase in the viral load (viral RNA measurement).
Which of the following is the best course of action in this patient?
Educational objective: Review factors that may influence HIV-RNA measurements in HIV infected patients.
Although threefold change in the viral load (HIV-1 RNA levels) is considered significant in patients with HIV infection, there are certain situations when even greater change may not be significant.
It was shown that viral RNA levels could rise transiently during acute illnesses (any of the opportunistic infections – for example), an outbreak of herpes simplex infection, or after vaccination against a variety of pathogens including influenza, pneumococcus, and tetanus. These increases may be quite dramatic, up to tenfold (rarely, even greater), and may persist for a month or more. Thus, plasma HIV-1 RNA levels should not be measured within one month of any of these events.
A 64-year-old woman presents with constant left lower quadrant pain, low-grade fever, urgent loose non-bloody stools, and pneumaturia for one week.
Diagnostic tests that should be pursued at presentation include all of the following except:
Educational objective: Illustrate that endoscopy is contraindicated in acute diverticulitis.
This patient presents with acute diverticulitis with a colovesicular fistula. Endoscopy is contraindicated in acute diverticulitis due to its potential perforation risk. CT scan is the test of choice to demonstrate bowel wall thickening and abscess formation. The abdominal series will evaluate quickly and cheaply for perforation with free air. The barium enema (done carefully with low pressure) will show bowel edema and possibly the fistula tract. Retrograde cystopyelography may reveal the fistula tract.
Ref: 1. Ferzolo L B, Raptopoulos V, Silen: Acute Diverticulitis. New England Journal of Medicine. 338:1521-26, 1998. Review Article -- NEJM 1998; 338: 1521-1526 2. Rao P M, Rhea, J t, Novelline R A: Helical CT of Appendicitis and Diverticulitis. Radiologic Clinics of North America. 37:895-910, 1999.
A 68-year-old male patient presented with fever, increased white blood count with left shift, pain in left lower abdominal quadrant, and constipation for the last 48 hours. He has a history of several episodes of painless bleeding in the last 5 years. His weight has been stable during this time. Rectal exam reveals normal sphincter tone and mild tenderness more toward the left side of the abdomen.
Which of the following is the most likely diagnosis?
Educational objective: Review clinical features of acute diverticulitis.
This patient most likely has acute inflammation of the colonic diverticula. Prevalence of diverticulosis in the age group of this patient is about 40%.
About 70% of patients with diverticulosis remain asymptomatic, and the rest develop complications. Bleeding results from injury to the artery supplying this segment of the bowel, and it is painless. Most patients have minor or occult bleeding but up to 50% give a history of intermittent passage of maroon or bright red blood per rectum. Diverticulitis represents micro or macroscopic perforation of diverticulum followed by inflammation and focal necrosis. Left lower quadrant pain is the most common clinical feature (70% of cases). Pain is present more than 24 hours at presentation in 83% of cases. Nausea and vomiting are seen in 20-60% and constipation in 50 percent of patients. Diarrhea and urinary symptoms (dysuria, urgency and frequency) are also seen.
Acute prostatitis usually doesn’t have left lower quadrant pain associated with it; urinary symptoms predominate, and a rectal exam is markedly painful. Appendicitis is less likely because of the localization of pain. This is also an atypical presentation for colorectal cancer; because internal hemorrhoids may become infected, there is marked tenderness on rectal exam in this condition.
Educational objective: Review diagnostic procedures for acute diverticulitis.
The CT scan is the method of choice in investigation of patients suspected of having acute diverticulitis. It is used for diagnosis, assessment of severity, therapeutic intervention, and quantification of resolution of disease. Features of diverticulitis on CT scan are increased soft tissue density within pericolic fat (due to inflammation – 98%), colonic diverticula (84%), thickening of the bowel wall (70%), and soft tissue masses caused by phlegmon, fluid collections, and abscesses (35%). Hence, CT can be used to estimate the extent of inflammation and to follow changes with treatment. In addition it can be used as a guide to percutaneous drainage of abscesses, avoiding emergent surgery, and permitting single-stage elective surgical resection.
A contrast enema is safe if performed in the acute stage and by the single contrast technique. It is absolutely contraindicated in the presence of complications such as pneumoperitoneum or generalized peritonitis (however, water soluble contrast may be used). Compression, high-resolution is a new method with reported sensitivity in the range of 85-98% and specificities from 80-98%, and is still used less frequently than the CT scan. Routine plain abdominal plate is useful in exclusion of other causes of acute abdominal pain (intestinal obstruction, etc.), rather than in making the diagnosis of diverticulitis. Colonoscopy is to be avoided in the face of a potentially acute surgical abdomen.
Educational objective: Review indications for surgical intervention in patients with acute diverticulitis.
The overall requirement for surgery with the first attack of diverticulitis is 20-30%, and most of these patients have complicated diverticulitis.
Indications for emergency surgery during the acute phase of the disease are free bowel perforation (with generalized peritonitis), obstruction, failure to improve with conservative management (or clinical deterioration), and an abscess that cannot be drained percutaneously.
Indications for elective surgery are recurrent symptoms, persistent pericolic mass, inability to exclude carcinoma of the colon, relative (incomplete) obstruction, presence of the fistula (to the skin, urinary bladder etc.), and previous percutaneous drainage of an abscess (drainage allows for elective surgery instead of emergency).
Educational objective: Review clinical features and significance of CMV retinitis in HIV infected patients.
Cytomegalovirus (CMV) retinitis is the most common serious ocular complication of AIDS. It appears that highly effective antiretroviral therapy may prevent development of CMV retinitis. Most patients with CMV retinitis have a CD-4 cell count below 50 mm3.
CMV retinitis is typically painless, can cause blurring or loss of central vision, scotomata, floaters, or photopsia (flashing lights). It may lead to acute retinal detachment and acute loss of vision.
Diagnosis is made generally on clinical criteria by demonstration of white, fluffy or granular retinal lesions, often close to retinal vessels and associated with hemorrhage. Small lesions may be hard to recognize and serial fundoscopic examinations are sometimes required to make the diagnosis.
Educational objective: Recognize importance of adequate antiretroviral therapy.
Recent studies have established the enormous impact that aggressive antiretroviral therapy has on the course of HIV infection. The rate of AIDS deaths fell by 12% in the United States in 1996 and by 44% in 1997. In addition, hospital admissions for HIV-related complications decreased by 30% in 1998 in comparison to 1995. This applies even to patients with advanced disease (CD-4 < 100 cells/mm3) in whom mortality decreased in 1997 to one third of that from 1995.
There is also, with the advent of highly effective antiretroviral therapy, marked decrease in the incidence of the three major opportunistic infections – pneumocystis carinii, mycobacterium avium complex, and cytomegalovirus.
Improvement in preventive measures is observed in certain populations at risk (gay men), but not in others (intravenous drug users), and decreases in the mortality or incidence of opportunistic infections cannot be explained by these changes.
Also there is no shift in epidemiology to HIV-2, or to the less virulent HIV-1.
Educational objective: Review indications for antiretroviral therapy.
The status of the patient’s HIV infection (CD-4 cell load and viral load) is an important parameter in the decision-making regarding start of multidrug antiretroviral therapy (of course, willingness of the patient to take medications, and probability of compliance also should be taken into account). There are three major indications for the initiation of antiretroviral therapy in HIV-infected patients:
There is still some controversy about treatment in asymptomatic patients with CD-4 cell counts of 350-500 cells/mm3 and viral load of 5000-10,000 copies/ml.
Educational objective: Understand factors that diminish efficacy of antiretroviral therapy.
Continued homosexual activity has no effect on efficacy of highly effective antiretroviral therapy. However, there ARE several other factors identified that decrease the chance of successful therapy. Poverty and inner city residence are two of them (this may be related to noncompliance due to expense of the drugs). Compliance to treatment regimen is critical for an optimal outcome. This is particularly true for the HIV protease inhibitors, since fluctuations in the serum drug concentrations promote drug resistance not only to a particular drug but also to other protease inhibitors or non-nucleosidase reverse transcriptase inhibitors. There is no cross-resistance between the three classes of drugs.
The response in terms of viral load reduction is better in patients with higher initial CD-4 cell counts and in those who did not receive previous antiretroviral therapy.
Educational objective: Review the indications for non-surgical antimicrobial prophylaxis.
All of the above are true except B. Both amantadine and rimantadine are 70 to 90% effective. Rimantadine is more expensive than amantadine but has fewer side effects.
Those agents are an adjunct, not a substitute of influenza vaccine. The usual dose for both of them is 100 mg orally twice daily. Dose reduction is recommended in elderly patients and in those with impaired liver function
A 27-year-old homosexual man with history of HIV infection and heroin abuse came to his physician's office with complaints of painful swallowing, chest pain, nausea, and one episode of hematemesis. He has had this problem for the last week.
Endoscopy was done which revealed serpiginous esophageal ulcers. Some of them coalesced forming giant ulcers which were localized in the distal esophagus. Biopsy of the center of the ulcer was done. Routine histology showed intranuclear and small intracytoplasmic inclusions in large fibroblasts and endothelial cells of blood vessels.
Which one of the following is the most possible cause of this patient's condition?
Educational objective: Review differences in clinical presentation between herpes simplex, Varicella-Zoster, and cytomegalovirus infections in HIV infected patients.
Herpes simplex is a frequent cause of esophagitis in immunocompromised patients. Herpetic vesicles on the nose or lips sometimes provide clues to the diagnosis. Endoscopy shows vesicles and small, discrete, punched-out superficial ulcerations with or without fibrinous exudate. Mucosal cells from a biopsy sample taken from the edge of the ulcer show balloon degeneration, ground glass changes in the nuclei with eosinophilic intranuclear inclusions (Cowdry type A) and giant cell formation on routine stains.
Cytomegalovirus infection occurs only in immunocompromised individuals. Clinical picture and histology were described above in this patient’s presentation. A ganciclovir 5 mg/kg every 12 hour intravenously is the treatment of choice.
In an immunocompromised host, Varicella-Zoster virus can cause esophagitis with vesicles and confluent ulcers and usually resolves spontaneously, but it may cause necrotizing esophagitis in a severely immunocompromised host. Histologically Varicella-Zoster infection is difficult to distinguish from HSV. Distinction can be made immunohistologically or by culture. HIV can be associated with a self-limited syndrome of esophagitis associated with oral ulcers and a maculopapular skin rash, which occurs at the time of seroconversion. Candida species are normal comensals in the throat but become pathogenic and produce esophagitis in immunodeficiency states. Endoscopy shows small, yellow-white raised plaques with surrounding erythema. In extensive disease confluent linear and nodular plaques are seen. Diagnosis is made by demonstration of yeast or hyphal forms in plaque smears and exudate stained with Gram's, silver stain or periodic acid-schiff.
A 57-year-old man went to his physician's office with complaints of pain in his left testicle which started about three days ago post sexual intercourse. It radiated along the spermatic cord. Also he has had pain on the tip of his penis after urination. For the last 24 hours he has had mild fever. On exam his left testicle was swollen and extremely painful to palpation. Complete blood count revealed white blood count of 14.7. Gram stain of a smear of urethral discharge showed multiple white blood cells without visible organisms.
His past medical history is remarkable for hypertension and chronic atrial fibrillation. His medications are metoprolol, enalapril, warfarin and amiodarone.
Which one of the following is the most probable diagnosis of this patient's condition?
Educational objective: Review clinical features of acute epididymitis.
This patient presents with typical signs and symptoms of acute epididymitis. Most cases are infectious and can be divided into two categories that have different etiologic agents. Sexually transmitted forms are associated with urethritis and result from chlamydia trachomatis or N. gonorrhoeae. Non-sexually transmitted forms are associated with urinary tract infections, and are caused by gram-negative rods. Symptoms usually follow physical strain, (heavy lifting), trauma or sexual activity. Associated symptoms of urethritis or cystitis may occur. Fever and scrotal swelling are usually apparent. White cells without visible organisms on urethral smear represent nongonococcal urethritis, and C. trachomatis is the most likely pathogen.
A 34-year-old man was admitted to the hospital with complaints of severe epigastric pain and nausea. On the third day of his hospital stay he developed fever. It was in the range 38.0-38.2ºC. Blood and urine cultures were sent. Stool was obtained for WBC, ova, parasites, bacterial cultures and Clostridium difficile toxin. CT scan of paranasal sinuses, thorax and abdomen was done. HIDA scan was performed. Patient underwent EGD. PPD was nonreactive. Cultures were negative and the all the above-mentioned tests did not reveal an overt source of infection.
Ventilation-perfusion scan was low probability for pulmonary embolism. Transesophageal echocardiogram did not reveal any valve vegetations. His WBC was 8.4 with 18% bands. On the seventh hospital day patient was still febrile and the reason for his fever was unknown.
Which one of the following is the reason that this patient’s condition cannot be qualified as fever of unknown origin?
Educational objective: Review criteria for diagnosis of fever of unknown origin.
A new classification scheme divides fever of unknown origin (FUO) into four groups: classic, nosocomial, neutropenic and HIV associated. By definition classic FUO is an unexplained temperature higher than 38.3ºC for at least 2 weeks or three outpatient visits or 1 week of investigation in hospital.
Nosocomial fever of unknown origin is an unexplained temperature higher than 38.3ºC in a hospitalized patient in who fever was not present at admission; there must be at least 3 days of investigation with 2 days of culture incubation. This patient would qualify for nosocomial FUO if his temperature were higher than 38.3ºC. Elevated WBC is not part of the definition of FUO.
Neutropenic FUO is a temperature higher than 38.3ºC in a patient with a neutrophil count lower than 500 ml after 3 days of investigation with 2 days of culture incubation.
A 42-year-old HIV-infected female who is a known drug abuser presents with fever, pain in the right upper quadrant, and an ultrasound of the liver that shows a 9-cm, oval,and hypoechoic cyst in the right lobe. An ELISA assay detects the presence of antibodies to Entamoeba histolytica. Cysts from the same organism are found in a stool specimen.
Which one of the following is the most appropriate next step in management?
Educational objective: Review the treatment for Entamoeba histolytica infection in HIV infected patients.
AIDS patients have a high risk of infection with Entamoeba species. The most common amebic-related syndrome is that of colitis. Extraintestinal infection by the organism E. histolytica usually involves the liver. While the symptoms (fever, pain in the right upper quadrant, and pleural effusion) and the ultrasound findings (hypoechoic hepatic cysts) are nonspecific and could also be seen in bacterial abscesses or cancer, such symptoms in a patient with positive serology are absolutely sufficient in making the diagnosis of invasive amebiasis. For that reason, no further diagnostic studies are indicated in the patient. The drug of choice is metronidazole, though the less effective agent chloroquine might also be considered. Except in patients with threatened imminent rupture of the cyst, drainage or aggressive aspiration is not necessary.
A 34-year-old man wants to volunteer as a blood donor. He has not had have any significant medical problems in the past. He states that occasionally he has had some heaviness in his right upper quadrant as well as mild nausea.
The routine screening revealed that he is positive for HbsAg, negative for anti-HBs, positive anti HBc IgG, negative HBeAg, positive anti-HBe, negative anti-HCV.
Which one of the following is the correct interpretation of the serologic pattern of this patient?
Educational objective: Review interpretation of serologic findings in viral hepatitis.
The detection of HBsAg establishes infection with HBV and implies infectivity. IgG anti-HBcAg appears during acute Hepatitis B but persists indefinitely, whether the patient recovers (with the appearance of anti-HBs in serum) or develops chronic Hepatitis B (with persistence of HBsAg). In asymptomatic blood donors, an isolated anti-HBc with no other positive HBV serologic results is often a falsely positive result. HBcAg represents a secretary form of HBcAg that appears during the incubation period shortly after the detection of HBsAg. HBeAg indicates viral replication and infectivity. Persistence of HBeAg in serum beyond 3 months suggests an increased likelihood of chronic hepatitis B. Disappearance of HBeAg is often followed by the appearance of anti-HBe, signifying diminished replication and decreased infectivity.
Educational objective: Review the indications for treatment of asymptomatic bacteriuria.
There is no measurable benefit of treatment of asymptomatic bacteriuria in individuals with diabetes, or in elderly individuals (and, of course, in otherwise healthy subjects). Also there is no evidence that treatment of asymptomatic bacteriuria in the man confers any benefit (and is also hard to treat) in terms of prevention of subsequent renal failure or hypertension.
Those who should be treated include the following:
A 33-year-old Afro-American man who is a known intravenous heroin drug abuser is admitted to the hospital with complaints of generalized weakness and periorbital swelling for the last one month. His physical exam is remarkable only for mild facial and pretibial edema and needle stick marks over the skin of his arms.
His laboratory results are as follows: BUN-63 mg/dl, Cr-5.4 mg/dl, albumin-2.6 g/dl, cholesterol-270 mg/dl, triglycerides-340 mg/dl, 24 hours urinary protein-3.6 g, HIV serology-positive.
Which one of the following types of glomerulopathy is the most likely in this patient?
Educational objective: Review the features of HIV nephropathy.
HIV infection has been associated with focal segmental glomerulosclerosis, acute diffuse proliferative glomerulonephritis, and mesangioproliferative glomerulonephritis, including IgA nephropathy, MPGN, and membranous glomerulopathy. The classic and most common HIV–associated glomerulopathy is focal and segmental glomerulosclerosis (FSGS), an entity that is termed human immunodeficiency virus associated nephropathy (HIVAN). The latter may be the first manifestation of infection in otherwise asymptomatic patients. HIVAN is more common in blacks than in other ethnic groups and is more frequent in intravenous drug abusers with HIV infection than in homosexuals. The disease has been described in all high-risk groups, however, including infants of HIV positive mothers.
The typical clinical correlates of HIVAN are severe nephritic syndrome and rapid progression to end stage renal disease, occurring in weeks to months. There is no proven therapy for HIVAN. Anecdotal reports suggest a benefit of steroids, ACE-inhibitors, and zidovudine in reducing proteinuria, but there are no controlled trials to support their use.
Educational objective: Review clinical features and therapy for herpes-zoster.
This patient apparently has a clinical presentation that strongly suggests herpes-zoster infection. The drug indicated in this setting is acyclovir, but the dose that is required to be effective is higher than that usually used to treat herpes simplex infection (200 mg 5 times a day). Early treatment (within 72 hours) of herpes zoster infection with high dose of acyclovir (800 mg 5 times a day orally) is shown to increase the rate of rash healing and reduce the prevalence of postherpetic neuralgia. Capsaicin used locally 3-4 times a day is effective in the treatment of postherpetic neuralgia but has no place in treatment of acute episode.
Wet to dry dressing should not be applied to the lesions of herpes zoster.
Educational objective: Review spectra of cephalosporins.
First generation cephalosporins like cefazolin are best used for gram-positive cocci and for surgical prophylaxis. Cefotetan and cefoxitin have good anaerobic coverage. Ceftazidime, a third generation cephalosporin, is good for gram-negative coverage.
A 23-year-old woman comes to your office for a blood sugar checkup. She is currently 22 weeks pregnant and is healthy with no complaints. Her blood pressure is 110/70 mm/Hg and her blood sugar is 96 mg/dl.
Screening urinalysis reveals the following: Specific gravity - 1010 no glucose or protein leucocytes - 5-7 per high power field bacteria - numerous.
Which one of the following will you recommend?
Educational objective: Review therapy for asymptomatic bacteriuria during pregnancy.
The prevalence of asymptomatic bacteriuria in pregnancy is about 7%. Treatment of asymptomatic bacteriuria should last 7-10 days. Ampicillin and nitrofurantoin are effective and safe. Cultures should be repeated 1 week after therapy. Sulfamethoxazole-trimethoprim (Bactrim) is known to be teratogenic.
Educational objective: Review diagnostic methods for diagnosis of H. pylori infection.
Serum H. pylori antibody may remain positive for months to years after treatment of H. pylori and hence would not be helpful in documenting eradication of infection. However, it may be useful initially to diagnose H. pylori infection. Though esophagogastroduedonoscopy (EGD) with biopsy and staining for H. pylori would be the most accurate test, it is not cost effective. It is difficult to culture H. pylori.
A 62-year-old homeless man was admitted to the hospital for fever and productive cough of several weeks' duration. During the diagnostic workup a sputum smear was obtained and stained by Ziehl-Neelsen stain. Stain is shown in the picture.
Which of the following statements about his management is true?
This homeless man is presenting with a clinical picture of lower respiratory infection; sputum specimen stain reveals acid-fast bacilli (not gram-negative rods). In light of this presentation, his condition is most likely pulmonary tuberculosis. Close contact with patient is recognized as the most important risk factor for transmission of the disease. Thus, respiratory isolation is necessary for the period of time while patient is infective. It is general agreement that two weeks after start of the effective (multiple drug) therapy patient is no longer infective. Isolation may include use of monitored rooms with negative air pressure and with minimum of 6 air exchanges per hour. Exhaust of air is to the outdoors or recirculation through HEPA (high-efficiency-particulate-air) filters before recirculation within the hospital. Also, use of masks (approved by the National Institute for Occupational Safety and Health) by caregivers entering isolation rooms is an important part of the isolation. In cases where acid-fast bacilli (AFB) stain is positive there is no need for additional diagnostic procedures besides culture and susceptibility testing of the microorganism.
A 45-year-old diabetic female presented in the emergency room with chills and severe pain in her right thigh. Pain first started 3-4 days ago. It was dull, deep, constant, nonradiating, and without any relieving or aggravating factors. It was increasing in intensity from the beginning and now is 8/10 on the scale of 1-10. On physical examination patient is febrile (38.9ºC) and right thigh has 2-3 cm greater circumference than left one. There is no skin discoloration or increased surface temperature, but thigh is severely tender on palpation. CT scan of the thigh was ordered and in the picture the pilot x-ray is shown.
Which of the following is the most likely causative organism?
This presentation and x-ray picture are highly suggestive of gas gangrene. Gas gangrene is most commonly caused by exotoxin-producing Clostridium species (large, gram-positive, spore-forming bacilli). These anaerobic organisms are normally found in the soil and gastrointestinal tract. Traumatic gas gangrene, the most common type of infection, occurs through direct inoculation of a contaminated, ischemic wound. Also, it can occasionally occur after a surgical procedure. Spontaneous gas gangrene is caused by hematogenous spread of toxin-producing bacteria, often in immunocompromised patients. Exotoxin, and not bacterial proliferation, is responsible for the rapid spread of infection. Exotoxin causes muscle destruction and creates an anaerobic environment conducive to further growth of the bacilli. Products of tissue breakdown, such as CPK, myoglobin and potassium cause secondary toxicity.
Clostridium perfringens is the cause in 80-95% of cases.
C. septicum causes nearly one-third of all spontaneous gas gangrene cases. It is more aero tolerant than Clostridium perfringens and thus capable of infecting normal tissue.
Aeromonas hydrophila myonecrosis is another, but unusual, cause.
Mixed anaerobic infections are also relatively common causes of gas forming infections as well as streptococcus causing necrotizing fasciitis.
This patient presents with signs and symptoms of serious eye infection. On the picture conjunctival injection is visible as well as yellowish fluid collection in the bottom part of the anterior eye chamber (hypopyon). This is, in fact, purulent fluid in the anterior chamber. Hypopyon is associated with serious ocular infection such as infectious keratitis or endophtalmitis. Presence of the hypopyon presents an emergency and patients should be seen by an ophtalmologist in a matter of hours. Hyphema (collection of bloody fluid in anterior chamber) rather than hypopyon is associated with severe blunt or penetrating trauma to the ocular globe.
Vision disturbance, pain and ocular movement difficulties may be signs of intraocular tumors, but hypopyon is not sign associated with it.
Educational objective: Understand the etiology of struvite kidney stones.
Struvite stones are associated with urinary tract infections caused by Proteus and Klebsiella. Those stones are composed of magnesium ammonium phosphate (struvite), often in combination with calcium carbonate – apatite. Normal urine is undersaturated with ammonium phosphate and struvite stone formation only can occur if ammonia production is increased and when urinary pH is elevated (this decreases the solubility of phosphate). Both situations are present during the infections by Proteus or Klebsiella, the urease-producing organisms. Urease breaks down urinary urea into ammonia and carbon dioxide. The ammonia combines with water and the net result is increased availability of ammonium in alkaline urine.
A 34-year-old Caucasian man was seen in the office for an ulcer on the dorsum of his penis. Patient stated that initially 2 weeks ago there was a little red lump in this place, but now it has burst open and drained some pus. The ulcer is painful. On examination of the dorsum of the penis, there is an ulcer 1.5 cm in diameter with sharp borders and an erythematous bottom covered partially with grayish-yellowish exudate. There is also a new erythematous papule on the glans penis. Inguinal lymph nodes are enlarged and tender. Some of them appear fluctuant. A gram-stain of material from the ulcer reveals small gram-negative rods.
The patient is sexually active with multiple partners and had several encounters with prostitutes within the last month. Which of the following is the most likely diagnosis?
Educational objective: Review clinical features and emphasize chancroid as an important cause of genital ulcers in sexually active individuals.
Chancroid is a genital infection relatively rarely diagnosed in the U.S. (Only about 7% of clinics for sexually transmitted diseases test patients for haemophilus ducreyi). However, it is important to entertain this option in a differential diagnosis of patients with genital ulcers. The fact that this patient has a clinical picture characteristic of chancroid is not enough for diagnosis, but a gram-stain revealing small gram-negative rods is highly suggestive. For definite diagnosis, isolation of haemophilus ducreyi is necessary. This microorganism is fastidious and requires the presence of hemin and usually serum in the culture media to grow. (PCR techniques are developed for rapid diagnosis).
Syphilis is less likely in this patient as its ulcers are characteristically painless. Genital herpes is a common cause of recurrent genital ulcers that are painful, but these are usually smaller, multiple, and without marked lymphadenopathy. Lymphogranuloma venereum is caused by chlamydia trachomatis and it cannot be detected by gram stain. Granuloma inguinale (donovanosis) is caused by calymmatobacterium granulomatis and may appear as chancroid, but it is a much rarer condition.
Educational objective: Recognize clinical features and therapy for lymphangitic sporotrichosis.
This patient suffered what is most likely an infection with Sporothrix schenkii, a fungus living as a saprophyte on plants in many areas of the world. Infection usually occurs from subcutaneous tissue via a minor trauma. Because of that, nursery workers, florists, and gardeners are particularly at risk.
There are two forms of the disease, one localized to the place of inoculation (plaque sporotrichosis), and one with proximal extension via regional lymphatic (lymphangitic sporotrichosis). In lymphangitic sporotrichosis (which is the most common form of the disease) an almost painless nodule forms at the place of inoculation. Subsequently (over several weeks) similar nodules form along regional lymphatics. Nodules may discharge small amounts of pus and even ulcerate. Systemic dissemination is rare.
Plaque sporotrichosis presents as a red maculopapular, nontender granuloma at the site of inoculation. Diagnosis is by culture of pus, or skin biopsy. However, in the skin lesions organisms are hard to find. If left untreated sporotrichosis heals poorly and is capable of chronicity. Cutaneous sporotrichosis may be cured with a saturated solution of potassium iodide orally up to 4.5-9 ml daily in divided doses for 1 month after resolution of all skin lesions (this therapy is, however, poorly tolerated due to acneiform rash and gastrointestinal disturbances).
Itraconazole (100-200 mg/d) is much better tolerated. Amphotericin B may be used in systemic cases (up to 50% cure rate). Penicillin has no place in treatment; nor does surgical removal of nodes. Trimethoprim-sulfamethoxazole is used in a similar disease caused by Mycobacterium marinum.
Educational Objective: Review cases of proctitis.
Gonorrhea is the most common sexually transmitted bacterial infection and therefore is the correct answer in this list of reasons for proctitis.
Educational Objective: Illustrate the differences between SBP and infected dialysate fluid.
The organisms involved in infected dialysate fluid are mainly associated with the skin rather than the bowel, and dialysis usually doesn’t need to stop with intra-peritoneal antibiotic infusion.
Educational Objective: Illustrate subtle presentation of spontaneous bacterial peritonitis.
Any change in a patient with ascites may signal the onset of S.B.P. This patient with new onset encephalopathy, elevated WBC in serum, and ascites has S.B.P. Only 50 – 70% will have positive ascitic cultures and therefore antibiotics should be started when the ascitic WBC is above 250. Peritoneal TB has ascites with a lymphocytic predominance and 80% have a WBC count >500. Therapy of the encephalopathy is not necessary as it usually resolves with treatment of the infection.
Educational objective: Review laboratory features of acute poststreptococcal glomerulonephritis.
Poststreptococcal glomerulonephritis is caused by specific nephritogenic strains of group A, â-hemolytic streptococci. Children below 7 years of age are at highest risk, and incidence is higher after skin infections (25%) than after pharyngitis (5-10%). It occurs typically about 10 days after pharyngitis and 21 days after impetigo.
Renal failure is usually moderate, transient, and associated with only mild (if any) metabolic acidosis; the anion gap is only slightly, if at all, elevated.
Of the offered options in the questions only option E fulfills these criteria.
A 27-year-old female came to the emergency room because of a 24-hour history of worsening fever, fatigue and skin rash. She has been healthy in the past. She is in her fifth day of menstrual period for which she uses intravaginal tampons.
She appears in severe distress. Her vital signs are as follows: temp-37.8ºC, pulse-119 min, blood pressure 95/56 mmHg. Which of the following microorganisms is most likely the cause of her condition?
Educational objective: Review clinical features of toxic shock syndrome.
This patient presents with a clinical picture and history characteristic of toxic shock syndrome. Disease is most commonly caused by Staphylococcus aureus, but clinical symptoms are a result of the endotoxin produced by bacteria and not by the organism itself (so antibiotics are not sufficient for therapy and aggressive fluid resuscitation is always necessary). Clinical picture is dominated by signs of multiple organ system involvement (muscle damage, neurologic damage, abdominal pain, etc.) and hemodynamic instability (shock). Associated rash is usually diffuse, red, maculopapular and with desquamation of the palms and soles during the convalescent period. The use of tampons predisposes for infection.
Educational objective: Review treatment of herpes zoster in immunosuppressed patients.
This patient presents with an eruption highly suggestive of herpes zoster. This condition is caused by reactivation of the Varicella virus infection from dorsal spinal ganglia. Herpes zoster is most commonly seen in elderly patients and those who are immunosuppressed (patients on intense chemotherapy regimens or with AIDS). Presentation in question represents involvement of ophthalmic branch of fifth cranial nerve (trigeminal nerve). This distribution is particularly dangerous because of associated serious ocular complications. In addition, due to immunosupression this patient is in danger of disseminated herpes infection, and must be treated with intravenous administration of acyclovir instead of oral therapy. An ophtalmologist should also be consulted in all cases of periocular involvement with herpes zoster.
A 30-year-old male patient who underwent a kidney transplant two months ago came to the emergency room with extreme malaise and abdominal pain. The day before the visit he had a low-grade fever. On questioning about his bowel movements he states that he had several loose stools, but denies any nausea or vomiting. His pain is diffuse and he has lost all his appetite. On physical examination there is diffuse tenderness on palpation of the abdomen with maximum tenderness located in right upper quadrant. There is no rigidity or any palpable mass. Auscultation of the heart reveals tachycardia with regular rhythm and no murmurs or added heart tones.
Vital signs: pulse-130, Blood pressure-90/62 Temp-38.3ºC Pulse oximetry-92% saturation. Urinalysis and chest x-ray were both entirely normal. Laboratory findings were significant for Sodium of 131, Potassium 5.9 and ALT of 212.
Which one of the following is the most probable cause of his condition?
Educational objective: Review different infections occurring in immunosuppressed transplant patients.
Transplant patients have depressed cellular immunity due to immunosuppressive therapy necessary for graft maintenance. Certain infections appear in these patients at specific times after transplant surgery. Cytomegalovirus (CMV) infection typically occurs 1-4 months after surgery. This is usually a systemic infection and may present with encephalitis, hepatitis, retinitis, colitis, or adrenalitis.
During the first month after transplant most common are nosocomial bacterial infections.
Herpes simplex activation occurs usually within 6 weeks from the time of surgery.
Other infections occurring in a 1-4 month time frame include TBC, Listeria, Nocardia, Toxoplasmosis and pneumocystis carinii. Varicella-Zoster reactivation, Epstain-Barr and Hepatitis C virus infections occur in a 2-6 month time period after transplant surgery.
A 32-year-old female presents with bilateral irritation of the eyes. She is complaining of itching, sensation of a foreign body, excessive tearing and photophobia. On examination there is profuse mucopurulent discharge and matting of the lashes. When discharge is prepared by Gram-staining it reveala a lot of polymorphonuclear neutrophils and intracellular gram-negative diplococci.
What is the appropriate management for this patient?
Educational objective: review features and treatment of gonorrhea conjunctivitis.
This patient has bacterial conjunctivitis. Gram-stain strongly suggests Neisseria gonorrhoeae as a cause (gram-negative diplococci inside white blood cells). Patients with bacterial conjunctivitis can usually be treated on an outpatient basis with instruction to follow up with a physician in 24 hours if there is no improvement.
However, patients suspected of having gonococcal conjunctivitis need to be admitted to the hospital for intravenous antibiotic therapy (ceftriaxone is adequate choice) and irrigation of the eyes to remove bacteria, since this infection may lead to corneal ulceration and perforation resulting in endophtalmitis.
Educational objective: Review assessment of upper respiratory obstruction in children.
Upper airway obstruction may be caused by mechanical or inflammatory causes. Inflammatory causes are most commonly caused by viral infections, and are much more likely to be symptomatic in children than in adults (because of difference in size of major airways). It is important to assess a risk of complete obstruction due to epiglottitis and tracheitis, which are most commonly caused by bacterial infection (croup). Croup is usually preceded with viral upper respiratory infection, which is then followed by barky cough. Body temperature may be minimally elevated or as high as 40ºC. When calm, most children with croup are relatively free of stridor, but any agitation will increase symptoms due to faster flow of the air by the site of narrowing. The fact that this child has marked stridor even when calm is an ominous sign signifying impeding complete airway obstruction.
A 2-year-old child was seen in the emergency room where he was brought by his family for difficulty in breathing. On initial evaluation it is obvious that the child has inspiratory stridor. Father stated that patient had been having upper respiratory infection for a couple of days and then went on to develop a barking cough. Since this morning this harsh inspiratory stridor has been present. Patient has fever of 39.1ºC, heart rate of 120 min; respiratory rate of 28 min. Remainder of the examination is unremarkable.
Which of the following are studies most important in this situation?
Educational objective: Review appropriate management of infectious upper respiratory obstruction.
Evaluation of any patient with upper respiratory obstruction should include assessment of air entry (auscultation of breath sounds), evaluation of work of breathing (respiratory rate, use of accessory respiratory muscles, etc.), and adequacy of oxygenation (signs of cyanosis and oxygen saturation). Oxygen saturation should be assessed by pulse oximetry since invasive procedures are to be avoided in the presence of significant stridor until airway is secured.
The lateral neck radiograph is often normal in cases of croup, but it will identify edema of the epiglottis and may identify strandy membranes in cases of bacterial tracheitis.
CT-scan has no role in evaluation at this time.
Inspiratory and expiratory chest x-rays are used in evaluation of foreign body in airways.
A 2-year-old child was seen in the emergency room where he was brought by his family for difficulty breathing. On initial evaluation it is obvious that the child has inspiratory stridor. Father stated that patient had been having upper respiratory infection for a couple of days and then went on to develop a barking cough. Since this morning this harsh inspiratory stridor has been present. Patient has fever of 39.1ºC, heart rate of 120 min; respiratory rate of 28 min. Remainder of the examination is unremarkable.
Which one of the following microorganisms is most likely responsible for this child’s condition?
Educational objective: Review causes of laryngotracheobronchitis.
Laryngotracheobronchitis is the most common inflammatory cause of upper airway obstruction. About 75% of these cases are currently caused by parainfluenza virus infection. Other viruses known to be associated are adenoviruses and influenza virus. Before introduction of Hib vaccine, Haemophilus influenzae-type B was the most frequent cause in patients with epiglottitis.
Epiglottitis has also been associated with streptococcus pneumoniae infections.
Staphylococcus aureus has been implicated as a cause of secondary infections in bacterial tracheitis.
A 2-year-old child was seen in the emergency room where he was brought by his family for breathing difficulty. On initial evaluation it is obvious that the child has inspiratory stridor. Father stated that patient had been having an upper respiratory infection for a couple of days and then went on to develop a barking cough. Since this morning this harsh inspiratory stridor has been present. Patient has fever of 39.1ºC, heart rate of 120 min; respiratory rate of 28 min. Remainder of the examination is unremarkable.
After admitting the child to the hospital, which one of the following combinations is the best treatment for his condition?
Educational objective: Review appropriate therapy for laryngotracheobronchitis.
Treatment for croup depends on symptoms, and often a child with mild symptoms (just cough and mild fever) may be cared for at home. However, if there is evidence of increased airway obstruction it is necessary to hospitalize the patient. Often it is enough to provide humidified air for breathing since it will decrease respiratory distress and any laryngospasm within minutes of application. In addition, antipyretics will decrease the fever, metabolic rate and, potentially, the respiratory rate. These measures are sufficient in the majority of cases, but careful monitoring is essential to avoid further development of airway obstruction.
Use of steroids in these cases is still controversial, and antibiotics are of no use in viral illnesses. Racemic epinephrine may be useful, but it also requires careful monitoring and, often, repeated administration.
Clostridium difficile spores are not eradicated with alcohol-containing hand wipe fluid. Soap and water is still the main-stay!!
The following antibiotic prophylactic regimens are recommended by the American Heart Association (AHA) only for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis. High-risk cardiac conditions •Prosthetic cardiac valve •History of infective endocarditis •Congenital heart disease (CHD) ◦Unrepaired cyanotic CHD, including palliative shunts and conduits ◦Completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first 6 months after the procedure ◦Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibits endothelialization) •Cardiac transplantation recipients with cardiac valvular disease For patients with high cardiac risk, antibiotic prophylaxis is recommended for all dental procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa. The following dental procedures do not require endocarditis prophylaxis: •Routine anesthetic injections through noninfected tissue •Taking dental radiographs •Placement of removable prosthodontic or orthodontic appliances •Adjustment of orthodontic appliances •Placement of orthodontic brackets •Shedding of deciduous teeth •Bleeding from trauma to the lips or oral mucosa
The rash associated with mono and ampicillin is not an allergic reaction. Therefore it can be used safely here.
It is not contraindicated.
The BCG vaccination status has no impact on the interpretation of a tuberculin skin test.
Obtain a culture for suspected UTI in those who a resistent organism is suspected (nursing home or hospital bound), a pregnant patient, and those following previous treatment failure.
