HIV and TB co-infection in the ART era: CD4 count distributions and TB case fatality in Cape Town

Abstract

BackgroundIn Cape Town, the roll-out of antiretroviral therapy (ART) has increased over the last decade with an estimated coverage of 63% of HIV- positive patients in 2013. The influence of ART on the characteristics of the population of HIV-positive patients presenting to the primary care TB programme is unknown. In this study, we examined trends in CD4 count distribution, ART usage and treatment outcomes among HIV-positive TB patients in Cape Town from 2009 to 2013.MethodsData from the electronic TB register on all newly registered drug-sensitive TB patients ≥18 years were analyzed retrospectively. Descriptive statistics were used to compare baseline characteristics, the CD4 count distribution and TB treatment outcomes both by year of treatment and ART status at the start of TB treatment. Survival analyses were used to assess the change in mortality risk during TB treatment over time, stratified by ART status at start of TB treatment.Results118,989 patients were treated over 5 years. HIV prevalence among TB patients decreased from 50.9% in 2009 to 49.0% in 2013. The absolute number of HIV-positive TB cases declined by 13.2% between 2010 and 2013. More patients entered the TB programme on ART in 2013 compared to 2009 (30.0% vs 9.9%). Among these, the CD4 count distribution showed a year by year shift to higher CD4 counts. In 2013, over 75% of ART-naïve TB patients still had a CD4 count < 350 cells/mm3. ART initiation among ART-naive patients increased from 37.0 to 77.7% and TB case fatality declined from 7.4 to 5.2% (p < 0.001). In multivariate analysis a decrease in TB mortality was most strongly associated with CD4 count (Adjusted HR 0.82 per increase of 50 cells/mm3, 95% CI: 0.81–0.83, p < 001) and the initiation of ART during TB treatment (Adjusted HR 0.39, 95% CI: 0.35–0.42, p < 0.001).ConclusionComprehensive changes in the ART and TB treatment programmes resulted in incremental increases in ART coverage for HIV-positive TB patients and a subsequent decrease in TB case fatality due to increased ART uptake in HIV-positive ART-naïve patients. However TB still remained a major presenting opportunistic infection with the majority of cases occurring at low CD4 counts.Electronic supplementary materialThe online version of this article (10.1186/s12879-018-3256-9) contains supplementary material, which is available to authorized users.

Subclinical tuberculosis among adults with HIV: clinical features and outcomes in a South African cohort

“…Finally, since this study was conducted, HIV treatment guidelines have shifted to reflect the benefit of early ART initiation with regard to mortality, morbidity, and HIV transmission [32–35]. With wider ART coverage, TB-related mortality has been reduced [36], though the impact on the epidemiology and natural history of subclinical TB remains unknown.…”

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What Are the Barriers for Uptake of Antiretroviral Therapy in HIV-Infected Tuberculosis Patients? A Mixed-Methods Study from Ayeyawady Region, Myanmar

“…These indicate gross delays in the diagnosis of HIV and in the diagnosis of TB among PLHIV. Urgent measures need to be taken to prevent these delays-which include improving the HIV test uptake, which has been reported to be suboptimal in key populations and presumptive TB patients, implementation of 'test and treat' strategy, which has great potential for the prevention of HIV-associated TB, [21,22] and early diagnosis of TB while using Xpert MTB/RIF assay [23]. While all of these policies are in place in Myanmar, the extent of implementation varies.…”