Pulmonary embolism mimicking acute myocardial infarction.

Pulmonary embolism is a major cause of death in the United States. A high index of suspicion is required to achieve an accurate diagnosis. We report a case of a patient with syncope, ischemic electrocardiographic changes, and an elevated troponin I level, presenting just like acute myocardial infarction. The case highlights the value of an early use of 2-dimensional echocardiography in obtaining an accurate diagnosis, thus avoiding unnecessary and inappropriate treatment.

Reverse transcriptase genotype and antiretroviral susceptibility of human immunodeficiency virus isolates from patients with advanced disease treated with didanosine: correlation with virologic response and survival.

To identify correlates of virologic response and survival, the reverse transcriptase (RT) genotype and in vitro antiviral susceptibility of human immunodeficiency virus (HIV) isolates from 20 patients treated with didanosine were studied. Patients had advanced HIV disease and were intolerant to or had failed zidovudine. Neither RT genotype nor antiviral susceptibility testing, as determined by a peripheral blood mononuclear cell-based assay, correlated with a virologic response to didanosine, as determined previously by quantitative serum culture. Only one (8%) of 12 isolates obtained after 6-12 months of treatment showed mutation at codon 74 conferring didanosine resistance. Reversions were seen in three of five patients with pre-treatment zidovudine resistance mutations at codons 70, but in none of eight with mutations at codon 215. Pretreatment isolates encoding mutations at RT codon 215 or encoding codon 123 asp were associated with both significantly greater CD4 lymphocyte depletion and shorter survival. In this cohort of patients with advanced HIV disease, neither rapid emergence of didanosine resistance nor rapid reversion of zidovudine resistance was observed. To better understand the relationship between virologic response and in vitro susceptibility to didanosine, more precise tools may be needed.

Serious Pseudomonas aeruginosa infection in AIDS.

During a 7-year period, 32 patients with Pseudomonas aeruginosa infection were identified on an HIV treatment service at a university-affiliated teaching hospital. The number of cases increased from 2 in 1986 to 13 in 1992. Affected patients had evidence of advanced HIV infection. In those treated with antiretroviral therapy, 96% of infections occurred > 1 year after initial presentation with HIV disease. Eighteen cases of pneumonia and 14 nonpulmonary (central venous access device, soft tissue, middle ear-mastoid, corneal, and peritoneal) infections were seen. Comparison with matched controls identified use of a central venous access device and administration of aerosolized pentamidine, corticosteroids, or ganciclovir as risk factors for infection (odds ratios, 5.3, 6.5, 15.0, and 9.0, respectively; p = 0.004, 0.007, 0.02, and 0.02, respectively). Seventy-five percent of cases had community onset, but time since last hospital discharge was significantly shorter in study patients than in controls (mean difference, -85 days; 95% confidence interval, -24 to -146; p = 0.01). Among evaluable cases, outcome was fatal (survival < or = 30 days) in 2 of 16 (13%) patients in whom initial antibiotic therapy was appropriate and 8 of 14 (57%) patients in whom initial therapy was not appropriate (p = 0.016). Ten recurrent infections were seen in 8 of 21 patients who survived the initial infection. Median survival after onset of infection was only 80 days. Pseudomonas aeruginosa infection is an increasingly frequent, severe complication of advanced HIV disease. Several treatment and prevention strategies used in the management of advanced HIV disease are associated with an increased risk of infection.

Herpes simplex virus infection in cancer patients: prevention and treatment.

Herpes simplex virus (HSV) infection is common in patients receiving cytotoxic therapy for cancer. Almost all infections result from reactivation of latent virus during treatment-induced immunosuppression. Typical, self-limited orolabial or genital ulceration does not always require laboratory diagnosis or treatment, but HSV may present in an atypical fashion in cancer patients and cause more severe and prolonged mucocutaneous infection or visceral disease. The presence of antibodies to HSV identifies patients at risk for recurrent HSV infection. The treatment of choice is acyclovir, which may also be used to prevent infection in high-risk patients. Acyclovir resistance has been reported in patients with profound and prolonged immune deficiency, but remains rare in patients treated for cancer.