The bacteriology of pulmonary tuberculosis in a population with high human immunodeficiency virus seroprevalence.

SETTING

A public sector urban university hospital in Soweto, South Africa.

OBJECTIVE

To describe the utility of sputum smear microscopy and the prevalence of Mycobacterium tuberculosis resistance to antituberculosis drugs according to human immunodeficiency virus (HIV) serostatus in adults.

DESIGN

A retrospective descriptive study of consecutive cases using a record review.

RESULTS

We studied 412 adults with culture-proven pulmonary tuberculosis, of whom 185 (44.9%) were HIV-seropositive and had a significantly lower sputum smear positivity than HIV seronegatives (68% versus 79%, P < 0.05). Smear positivity was significantly higher in HIV-infected patients with CD4 counts < or = 50/mm3 compared to those with CD4 counts of 201-300/mm3 (P < 0.05). In patients with and those without a history of previous treatment for tuberculosis, resistance to one or more antituberculosis drugs was found in 32.2% and 13.6% of cases, respectively, while resistance to both isoniazid and rifampicin (multidrug-resistant tuberculosis [MDR]) was found in 15.3% and 4.5% of patients, respectively. There was no significant difference in resistance between HIV-positive and seronegative patients.

CONCLUSION

A strong tuberculosis control programme and good surveillance will be required to prevent the further spread of MDR tuberculosis. Surveys such as these are useful for monitoring control programmes.