High prevalence of tuberculosis in newly enrolled HIV patients in Zambia: need for enhanced screening approach.

SETTING: Tuberculosis (TB) remains a leading cause of morbidity and mortality in sub-Saharan Africa. In Zambia, smear microscopy and chest radiography (CXR) are the primary TB diagnostic tools, and most cases are not bacteriologically confirmed. OBJECTIVE: We implemented enhanced screening to determine the TB burden among new human immunodeficiency virus (HIV) clinic enrollees. DESIGN: Consecutive adult HIV clinic enrollees were screened, regardless of symptoms. All underwent microscopy (Ziehl-Neelsen/fluorescence microscopy) on three sputum specimens, physical examination, and digital CXR. Sputum, blood and urine specimens were cultured. Xpert(®) MTB/RIF testing was performed retrospectively. RESULTS: From July 2011 to April 2012, 399 patients were enrolled. The median age was 34.4 years; body mass index was 20.8 kg/m(2), CD4 count was 202 cells/µl and 86% were symptomatic. Culture-confirmed TB was diagnosed in 72/399 (18%) patients; an additional 31/399 (8%) were culture-negative but diagnosed clinically. Symptom screening for any cough, fever, weight loss or night sweats had high sensitivity (95%) but low specificity (14%) for detecting culture-confirmed cases. Among culture-confirmed cases, 35/72 (49%) were missed clinically and detected only by culture. Xpert was 64% sensitive and 98% specific. CONCLUSIONS: High TB prevalence was found in Zambians newly enrolled into HIV care. Screening with sensitive diagnostics should be considered with culture when feasible in this population.

Integrating active tuberculosis case finding in antenatal services in Zambia.

SETTING: Three out-patient antenatal care (ANC) clinics in Lusaka, Zambia. OBJECTIVE: To estimate tuberculosis (TB) prevalence in human immunodeficiency virus (HIV) infected and symptomatic, non-HIV-infected pregnant women and explore the feasibility of routine TB screening in ANC settings. DESIGN: Peer educators administered TB symptom questionnaires to pregnant women attending their first ANC clinic visit. Presumptive TB patients were defined as all HIV-infected women and symptomatic non-HIV-infected women. Sputum samples were tested using smear microscopy and culture to estimate TB prevalence. RESULTS: All 5033 (100%) women invited to participate in the study agreed, and 17% reported one or more TB symptoms. Among 1152 presumed TB patients, 17 (1.5%) had previously undiagnosed culture-confirmed TB; 2 (12%) were smear-positive. Stratified by HIV status, TB prevalence was 10/664 (1.5%, 95%CI 0. 7-2.8) among HIV-infected women and 7/488 (1.4%, 95%CI 0.6-2.9) among symptomatic non-HIV-infected women. In HIV-infected women, the only symptom significantly associated with TB was productive cough; symptom screening was only 50% sensitive. CONCLUSION: There is a sizable burden of TB in pregnant women in Zambia, which may lead to adverse maternal and infant outcomes. TB screening in ANC settings in Zambia is acceptable and feasible. More sensitive diagnostics are needed.

TB and HIV in the Central African region: current knowledge and knowledge gaps.

PURPOSE: Reliable and comprehensive data on the HIV/AIDS and TB co-pandemics from Central Africa remain scarce. This systematic review provides a comprehensive overview on current and past research activities in the region and provides a basis for future research work to close knowledge gaps. METHODS: The scientific literature was searched for publications meeting the following search terms: "tuberculosis" or "HIV" or "acquired immunodeficiency syndrome", combined with "Central Africa", or the names of individual countries within the region. Original studies, reviews and case series were included, and a selection of relevant articles was made. RESULTS: Most research in the field of HIV and TB has been conducted in Cameroon, where the epidemics have been described fairly well. The Democratic Republic of Congo ranked second on the amount of publications, despite the civil wars over the past several decades. Very little has been published on HIV and TB in the other countries, possibly due to the poor infrastructure of health care systems, lack of scientific capacity building or shortage of laboratory equipment. CONCLUSIONS: Despite the relatively high burden of HIV and TB in the Central African region, the amount of research activities on these topics is limited. A better understanding of the co-epidemics in this region is urgently needed. The occurrence of opportunistic infections, treatment complications and drug resistance in TB and HIV need to be better described; the failure of public health systems needs to be understood, and research infrastructure needs to be developed. Only then will it be possible to turn the tide against the HIV and TB epidemics in this region.