No abstract

The epidemiology of extrapulmonary tuberculosis (TB) is not well understood. We studied all cases of extrapulmonary TB reported in San Francisco during 1991-2000 to determine risk factors for extrapulmonary TB and the proportion caused by recent infection. Isolates were analyzed by IS6110-based restriction fragment-length polymorphisms analysis. There were 480 cases of extrapulmonary TB, of which 363 (76%) were culture positive; isolates were genotyped for 301 cases (83%). Multivariate analysis identified young age, female sex, and HIV infection as independent risk factors for nonrespiratory TB (excluding pulmonary, pleural, and disseminated TB). Pleural TB was less common in HIV-seropositive persons and women than were nonrespiratory forms of extrapulmonary TB. Pleural TB is different from other forms of extrapulmonary TB and is associated with the highest clustering rate (35% of cases) of all forms of TB. This high rate of clustering occurs because pleural TB is often an early manifestation of recent infection.

Treatment of multidrug-resistant tuberculosis in HIV-seronegative patients largely on an outpatient basis was feasible and was associated with high cure rates and lower cost than in other published studies. Patients with underlying HIV infection had very poor outcomes.

Long-lasting therapy for Mycobacterium kansasii lung disease with rifampincontaining multidrug regimens is needed to avoid relapses. The aim of the present study is to evaluate a short multidrug treatment regimen for M. kansasii lung disease.A retrospective observational study of 75 patients with M. kansasii lung disease was conducted in a teaching hospital from January 1990 to December 2005.In total, 75 (67.6%) out of 111 patients diagnosed with M. kansasii lung disease completed a 12-month multidrug treatment regimen, including rifampin, isoniazid and ethambutol, supplemented with streptomycin during the first 2-3 months. After a 41.5-month median follow-up, five (6.6%) patients relapsed. The relapse rate was 2.19 (95% confidence interval 0.71-5.12) per 100 person?yrs. Treatment compliance was considered to be appropriate in all five patients and no drug resistance developed in any case.In conclusion, a 12-month fixed-course treatment is effective in most cases of Mycobacterium kansasii lung disease, but may not be long enough for all patients.

Effective treatment of tuberculosis requires adherence to a minimum of 6 months treatment with multiple drugs. To improve adherence and cure rates, directly observed therapy is recommended for the treatment of pulmonary tuberculosis. We compared treatment outcomes among all culture-positive patients treated for active pulmonary tuberculosis (n = 372) in San Francisco County, California from 1998 through 2000. Patients treated by directly observed therapy at the start of therapy (n = 149) had a significantly higher cure rate compared with patients treated by self-administered therapy (n = 223) (the sum of bacteriologic cure and completion of treatment, 97.8% versus 88.6%, p < 0.002), and decreased tuberculosis-related mortality (0% vs. 5.5%, p = 0.002). Rates of treatment failure, relapse, and acquired drug resistance were similar between the two groups. Forty-four percent of patients who received self-administered therapy had risk factors for nonadherence and should have been assigned to directly observed therapy. We conclude that treatment plans that emphasize directly observed therapy from the start of therapy have the greatest success in improving tuberculosis treatment outcomes.

In the setting of human immunodeficiency virus (HIV) infection, the clinical implications of American Thoracic Society (ATS) diagnostic criteria and the significance of a single positive respiratory culture for Mycobacterium kansasii are unknown. We retrospectively studied HIV-infected patients with pulmonary M. kansasii isolated between 1989 and 2002 at one institution. Of 127 patients, 33% fulfilled ATS disease criteria. Twenty-nine percent received at least three active drugs for at least 3 months, and 53% died. In survival analysis, a lower CD4 count (hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.1-2.3) and positive smear microscopy (HR, 2.8; 95% CI, 1.3-6.1) were associated with mortality, whereas antiretroviral therapy (HR, 0.3; 95% CI, 0.1-0.8) and M. kansasii treatment (HR, 0.4; 95% CI, 0.2-0.9) were associated with survival. ATS criteria did not predict mortality (HR, 0.9; 95% CI, 0.4-1.9). Fifteen patients (12%) apparently had indolent infection, not requiring immediate therapy. They had fewer positive cultures and lower rates of positive smear microscopy and ATS-defined disease. In HIV-infected patients with pulmonary M. kansasii infection, predictors of survival include higher CD4 counts, antiretroviral therapy, negative smear microscopy, and adequate treatment for M. kansasii infection, but not ATS diagnostic criteria. Withholding treatment in HIV-infected patients with respiratory M. kansasii isolates should only be considered with negative smear microscopy, few positive cultures, and mild immunosuppression.

No abstract

Although most cases of tuberculosis in HCWs, as in non-HCWs, developed as a result of endogenous reactivation of latent infection, at least half of clustered cases of tuberculosis in HCWs were related to work. The number of work-related cases of tuberculosis in HCWs decreased during the study period.