Childhood tuberculosis in the Bronx, New York.

The resurgence of tuberculosis (TB) in New York City in the period 1978-92 has been closely linked to the AIDS epidemic but the increase of active TB in areas of urban poverty also implies increased community exposure. We have examined the ecological relation between community rates of AIDS and residential crowding and cases of active TB in Bronx children under age 5. Residential crowding was defined as the percent of households with more than 1 person per room. All childhood TB cases reported between 1986 and 1992 for the Bronx (n = 75) were included. Cumulative AIDS mortality rates for adult females through 1990 represented community HIV burden. All data were coded by the 64 health areas of the borough. We examined trends in these data and used Poisson regression to model the effect of HIV burden and residential crowding on TB risk. For the Bronx as a whole the two variables of TB and residential crowding showed a clear temporal correspondence for the period 1970-90. Residential crowding was associated with poverty and greater dependence on public assistance, large household size, Hispanic ethnicity, and a higher proportion of young children. The overall TB case rate increased with the proportion of crowded households, with a rise from 1.47 to over 8 cases per 10,000 children as the proportion of crowded households increased. At both the lowest and highest levels of AIDS mortality in these areas, the childhood TB risk increased as crowding increased. Children living in areas of the Bronx in which over 12 percent of homes are severely overcrowded were 5.6-fold more likely to develop active TB, even after holding constant the presumed HIV burden in each local community. While HIV infection, the newest risk factor for TB, appears to play a critical role in the resurgent epidemic, our findings show that the earliest known TB risk factors, poverty and household crowding, are still potent forces.

High risk of active tuberculosis in HIV-infected drug users with cutaneous anergy.

OBJECTIVES: To determine the incidence of active tuberculosis in human immunodeficiency virus (HIV)-seropositive and HIV-seronegative drug injectors with cutaneous anergy and to examine the effectiveness of isoniazid chemoprophylaxis in preventing tuberculosis among drug injectors with positive tuberculin test results. DESIGN AND SETTING: Prospective observational study linked to an ongoing study of HIV infection within a New York City (NY) methadone program; subjects also underwent routine intradermal tuberculin testing and multiple-antigen delayed-type hypersensitivity skin testing. The 31-month study period ended December 31, 1990. METHODS: Anergic subjects and tuberculin reactors who were HIV seropositive were compared by HIV disease status and CD4+ T-lymphocyte levels. Tuberculosis incidence was calculated for anergics (none treated with isoniazid) and for treated and untreated tuberculin reactors, by HIV serological status. RESULTS: Among those seropositive for HIV, anergic subjects had more advanced HIV disease and fewer CD4+ cells (median 0.33 vs 0.56 x 10(9)/L, P less than .01) compared with tuberculin reactors, although neither clinical status nor CD4+ cell counts consistently predicted anergy. Five (7.6%) of 68 anergic subjects who were HIV seropositive and none of 52 anergic subjects who were HIV seronegative (n = 18) or of unknown (n = 34) HIV serological status developed active tuberculosis during the study period (P less than .05). The tuberculosis incidence rate among anergic subjects who were HIV seropositive was 6.6 cases per 100 person-years (95% confidence interval [Cl], 2.1 to 15.3). Of 25 HIV-seropositive tuberculin reactors who did not receive or complete 12 months of isoniazid prophylaxis, tuberculosis incidence was 9.7 cases per 100 person-years (95% Cl, 2.6 to 24.7; P = 0.56, compared with the rate among anergic HIV seropositives); there were no cases of tuberculosis in 53.4 person-years of follow-up for 27 HIV-seropositive tuberculin reactors who received 12 months of prophylaxis (rate difference between treated and untreated groups, 9.7 cases per 100 person-years, 95% Cl, 1.3 to 18.0). CONCLUSION: Drug injectors with cutaneous anergy who are seropositive for HIV are at high risk of active tuberculosis, similar to that among untreated HIV-seropositive tuberculin reactors. A decreased incidence of active tuberculosis was seen in HIV-seropositive tuberculin reactors receiving 12 months of isoniazid chemoprophylaxis, compared with untreated or partially treated subjects. These results support the routine use of delayed-type hypersensitivity testing to accompany tuberculin testing for drug injectors with known or suspected HIV infection, and consideration of isoniazid prophylaxis for anergic as well as tuberculin-reactive subjects who are HIV seropositive, in populations with a high prevalence of coexisting HIV and Mycobacterium tuberculosis infection.