Tuberculosis among adults starting antiretroviral therapy in South Africa: the need for routine case finding

Aurum Institute, Johannesburg, South Africa.
The International Journal of Tuberculosis and Lung Disease (Impact Factor: 2.76). 07/2012; 16(9):1252-9. DOI: 10.5588/ijtld.11.0733
Source: PubMed

ABSTRACT To investigate the prevalence of and evaluate screening modalities for undiagnosed tuberculosis (TB) in antiretroviral therapy (ART) eligible adults in South Africa.
Individuals were screened for TB using symptoms, chest radiograph (CXR) and two sputum specimens for microscopy and culture, and were then followed for <6 months to determine TB diagnoses.
Among 361 participants (67% female, median age 38 years, median CD4 count 120 cells/mm(3)), 64 (18%) were sputum culture-positive; 114 (32%) fulfilled any TB case definition (culture- and/or smear-positive, or improvement on specific treatment). Symptom screening comprising any of cough, appetite loss or night sweats > 2 weeks had a sensitivity and specificity of respectively 74.5% and 50.8%. Sensitivity was increased by CXR (to 96.1%), but not by smear microscopy. The World Health Organization symptom screen had a sensitivity and specificity of respectively 96.1% and 5.2% in our study population; the addition of CXR increased sensitivity to 100%. Median time to TB treatment was 8 days for diagnoses based on CXR (n = 72) vs. 37 days for diagnoses based only on sputum culture (n = 14).
The very high prevalence of undiagnosed TB among patients presenting for ART mandates their routine investigation. CXR improved sensitivity substantially, allowed rapid treatment initiation and should be routine, where available, pending better point-of-care diagnostics.

1 Bookmark
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background : The tuberculosis (TB) case detection rate has stagnated at 60% due to disorganized case finding and insensitivity of sputum smear microscopy. Of the identified TB cases, 4% die while being treated, monitored with tools that insufficiently predict failure/mortality. Objective : To explore the TBscore, a recently proposed clinical severity measure for pulmonary TB (PTB) patients, and to refine, validate, and investigate its place in case finding. Design : The TBscore's inter-observer agreement was assessed and compared to the Karnofsky Performance Score (KPS) (paper I). The TBscore's variables underlying constructs were assessed, sorting out unrelated items, proposing a more easily assessable TBscoreII, which was validated internally and externally (paper II). Finally, TBscore and TBscoreII's place in PTB-screening was examined in paper III. Results : The inter-observer variability when grading PTB patients into severity classes was moderate for both TBscore (κ W=0.52, 95% CI 0.46-0.56) and KPS (κ W=0.49, 95% CI 0.33-0.65). KPS was influenced by HIV status, whereas TBscore was unaffected by it. In paper II, proposed TBscoreII was validated internally, in Guinea-Bissau, and externally, in Ethiopia. In both settings, a failure to bring down the score by ≥25% from baseline to 2 months of treatment predicted subsequent failure (p=0.007). Finally, in paper III, TBscore and TBscoreII were assessed in health-care-seeking adults and found to be higher in PTB-diagnosed patients, 4.9 (95% CI 4.6-5.2) and 3.9 (95% CI 3.8-4.0), respectively, versus patients not diagnosed with PTB, 3.0 (95% CI 2.7-3.2) and 2.4 (95% CI 2.3-2.5), respectively. Had we referred only patients with cough >2 weeks to sputum smear, we would have missed 32.1% of the smear confirmed cases in our cohort. A TBscoreII>=2 missed 8.6%. Conclusions : TBscore and TBscoreII are useful monitoring tools for PTB patients on treatment, as they could fill the void which currently exists in risk grading of patients. They may also have a role in PTB screening; however, this requires our findings to be repeated elsewhere.
    Global Health Action 05/2014; 7:24303. DOI:10.3402/gha.v7.24303 · 1.65 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The syndemic of human immunodeficiency virus (HIV)/tuberculosis (TB) co-infection has grown as a result of the considerable sociogeographic overlaps between the two epidemics. The situation is particularly worrisome in countries with high or intermediate TB burden against the background of a variable HIV epidemic state. Early diagnosis of TB disease in an HIV-infected person is paramount but suffers from lack of sensitive and specific diagnostic tools. Enhanced symptom screening is currently advocated, and the wide application of affordable molecular diagnostics is urgently needed. Treatment of TB/HIV co-infection involves the concurrent use of standard antiretrovirals and antimycobacterials during which harmful drug interaction may occur. The pharmacokinetic interaction between rifamycin and antiretrovirals is a case in point, requiring dosage adjustment and preferential use of rifabutin, if available. Early initiation of antiretroviral therapy is indicated, preferably at 2 weeks after starting TB treatment for patients with a CD4 of
    Respirology 08/2013; 18(6). DOI:10.1111/resp.12120 · 3.50 Impact Factor