Browsing by Author "Henostroza G"

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Derivation of a tuberculosis screening rule for sub-Saharan African prisons.
(2014-Jul) Harris JB; Siyambango M; Levitan EB; Maggard KR; Hatwiinda S; Foster EM; Chamot E; Kaunda K; Chileshe C; Krüüner A; Henostroza G; Reid SE
SETTING: Lusaka Central Prison, Zambia. OBJECTIVE: To derive screening rules for tuberculosis (TB) using data collected during a prison-wide TB and human immunodeficiency virus (HIV) screening program. DESIGN: We derived rules with two methodologies: logistic regression and classification and regression trees (C&RT). We evaluated the performance of the derived rules as well as existing World Health Organization (WHO) screening recommendations in our cohort of inmates, as measured by sensitivity, specificity, and positive and negative predictive values. RESULTS: The C&RT-derived rule recommended diagnostic testing of all inmates who were underweight (defined as body mass index [BMI] < 18.5 kg/m(2)] or HIV-infected; the C&RT-derived rule had 60% sensitivity and 71% specificity. The logistic regression-derived rule recommended diagnostic testing of inmates who were underweight, HIV-infected or had chest pain; the logistic regression-derived rule had 74% sensitivity and 57% specificity. Two of the WHO recommendations had sensitivities that were similar to our logistic regression rule but had poorer specificities, resulting in a greater testing burden. CONCLUSION: Low BMI and HIV infection were the most robust predictors of TB in our inmates; chest pain was additionally retained in one model. BMI and HIV should be further evaluated as the basis for TB screening rules for inmates, with modification as needed to improve the performance of the rules.
High prevalence of tuberculosis in newly enrolled HIV patients in Zambia: need for enhanced screening approach.
(2016-Aug) Henostroza G; Harris JB; Chitambi R; Siyambango M; Turnbull ER; Maggard KR; Krüüner A; Kapata N; Reid SE
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.
(2014-Dec) Kancheya N; Luhanga D; Harris JB; Morse J; Kapata N; Bweupe M; Henostroza G; Reid SE
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.
Performance of Xpert
(2020-Dec-21) Kasaro MP; Chilyabanyama ON; Shah NS; Muluka B; Kapata N; Krüüner A; Mwaba I; Kaunda K; Coggin WL; Wen XJ; Henostroza G; Reid S
SETTING: Peri-urban health facilities providing HIV and TB care in Zambia. OBJECTIVE: To evaluate 1) the impact of Xpert DESIGN: Quasi-experimental study design with the first cohort evaluated per standard-of-care (SOC; first sputum tested using smear microscopy) and the second cohort per an algorithm using Xpert as initial test (intervention phase; IP). Xpert testing was provided onsite in Chongwe District, while samples were transported 5-10 km in Kafue District. TB was confirmed using mycobacterial culture. RESULTS: Among 1350 PLHIV enrolled, 156 (15.4%) had confirmed TB. Time from TB evaluation to diagnosis ( CONCLUSION: Xpert improved time to diagnosis and treatment initiation, but there was no difference in all-cause mortality. High sensitivity of Determine TB-LAM Ag at lower CD4 count supports increased use in settings providing care to PLHIV, particularly with advanced HIV disease.
Poor continuity of care for TB diagnosis and treatment in Zambian Prisons: a situation analysis.
(2018-Feb) Hatwiinda S; Topp SM; Siyambango M; Harris JB; Maggard KR; Chileshe C; Kapata N; Reid SE; Henostroza G
OBJECTIVES: Prisons act as infectious disease reservoirs. We aimed to explore the challenges of TB control and continuity of care in prisons in Zambia. METHODS: We evaluated treatment outcomes for a cohort of inmates diagnosed with TB during a TB REACH funded screening programme initiated by the Zambia Prisons Service and the Centre for Infectious Disease Research in Zambia. RESULTS: Between October 2010 and September 2011, 6282 inmates from six prisons were screened for TB, of whom 374 (6.0%) were diagnosed. TB treatment was initiated in 345 of 374 (92%) inmates. Of those, 66% were cured or completed treatment, 5% died and 29% were lost to follow-up. Among those lost to follow-up, 11% were released into the community and 13% were transferred to other prisons. CONCLUSIONS: Weak health systems within the Zambian prison service currently undermines continuity of care, despite intensive TB screening and case-finding interventions. To prevent TB transmission and the development of drug resistance, we need sufficient numbers of competent staff for health care, reliable health information systems including electronic record keeping for prison facilities, and standard operating procedures to guide surveillance, case-finding and timely treatment initiation and completion.