Dose-related adverse events in South African patients prescribed clofazimine for drug-resistant tuberculosis

Background. Optimal drug levels and minimal toxicity are critical factors in improving treatment outcomes for patients prescribed new and repurposed medicine for drug-resistant (DR) tuberculosis (TB). The optimal dose and dose-related safety of clofazimine (CFZ), a repurposed medicine for DR TB, in the South African (SA) population are unknown.Objectives. To report on dose-related adverse events in patients receiving CFZ plus a background regimen for DR TB.Methods. In a retrospective review of patient folders from 2012 to 2014, adverse events documented for patients receiving high- (≥200 mg) and low-dose (100 mg) CFZ in a centralised DR TB hospital in KwaZulu-Natal Province, SA, were investigated for an association between dose-weight interactions and adverse events.Results. Of 600 patients included, 78.7% (n=472) weighed ≥50 kg. Of these, 17.4% (n=82) received 100 mg CFZ and 82.6% (n=390) received >200 mg. Of 128 patients (21.3%) who weighed <50 kg, 68.0% (n=87) received 100 mg CFZ and 32.0% (n=41) received ≥200 mg. Of 463 patients (77.2%) who were HIV-positive, 94.0% were on antiretrovirals. There was no difference between the dose-weight cohorts in the background regimen given in addition to high- or low-dose CFZ. The frequency and types of adverse events observed were similar to the published literature. When analysed per dose-weight cohort, patients weighing <50 kg and receiving high-dose CFZ (≥200 mg) had a 2.6 times higher risk of any adverse event (adjusted odds ratio (aOR) 2.57; 95% confidence interval (CI) 1.02 - 6.05; p=0.05: reference category <50 kg and 100 mg). Patients weighing <50 kg and receiving high-dose CFZ had a 3.3 times higher risk of gastrointestinal adverse events than patients weighing <50 kg and receiving 100 mg CFZ (aOR 3.30; 95% CI 1.51 - 7.19; p=0.003). A high risk of chest pain was observed in patients receiving high- and low-dose CFZ, irrespective of weight. Patients weighing <50 kg receiving high-dose CFZ had a slightly higher risk of adverse events related to the skin (aOR 1.2; 95% CI 0.55 - 2.62; p=0.7) There were no documented reports of the CFZ dose being reduced or the drug being stopped due to adverse events in the sample population.Conclusions. There is an association between dose-weight interaction and adverse events. The odds of any adverse event occurring were higher when low-weight patients (<50 kg) received high-dose CFZ (≥200 mg). Gastrointestinal and skin-related adverse events were more common when high-dose CFZ was used in patients weighing <50 kg. Chest pain was reported in patients receiving high- and low-dose CFZ, irrespective of weight, and may be a symptom of cardiac toxicity. Plasma concentrations of CFZ may be affected by drug-drug interactions, so active drug safety monitoring including electrocardiograms is recommended routinely when CFZ is part of the regimen

XDR-TB in South Africa: No Time for Denial or Complacency

Singh and colleagues discuss the threat to regional and global public health posed by XDR-TB in KwaZulu-Natal, and propose new measures to control the outbreak

HIV-Associated Tuberculosis

The intersecting HIV and Tuberculosis epidemics in countries with a high disease burden of both infections pose many challenges and opportunities. For patients infected with HIV in high TB burden countries, the diagnosis of TB, ARV drug choices in treating HIV-TB coinfected patients, when to initiate ARV treatment in relation to TB treatment, managing immune reconstitution, minimising risk of getting infected with TB and/or managing recurrent TB, minimizing airborne transmission, and infection control are key issues. In addition, given the disproportionate burden of HIV in women in these settings, sexual reproductive health issues and particular high mortality rates associated with TB during pregnancy are important. The scaleup and resource allocation to access antiretroviral treatment in these high HIV and TB settings provide a unique opportunity to strengthen both services and impact positively in meeting Millennium Development Goal 6

Social constraints to TB/HIV healthcare: accounts from coinfected patients in South Africa.

There is a growing imperative to improve the coordination and collaboration of tuberculosis (TB) and HIV healthcare services in response to escalating rates of TB/HIV coinfection. Patient-specific challenges associated with the delivery of TB/HIV care have been minimally explored in this regard. As part of a larger study conducted in South Africa, this article highlights coinfected patients’ experiences with TB and HIV healthcare in light of their broader social environments. Qualitative, in-depth interviews were conducted with 40 adult, coinfected patients (24 women and 16 men) and eight key-informant healthcare workers at three urban/peri-urban, ambulatory, public health clinics in the high-burden province of KwaZulu-Natal. Transcribed interviews were analyzed under a modified grounded theory approach to capture subjective meanings of healthcare experience subsequent to patients’ codiagnosis with TB and HIV. Emerging analytic themes highlighted critical sociomedical constraints to TB/HIV care in relation to patients’ income and employment, eligibility for social assistance and antiretroviral treatment, fears around illness disclosure, social and material support, and treatment adherence. Patients’ healthcare experiences were bound by their poor access to essential resources, multiple life responsibilities, disparate gender roles, limits within the healthcare system, and the stigmatizing social symbolism of their illness. Overlapping social inequalities perpetuated coinfected patients’ experiences with stigma and collectively mediated their health decisions around disclosure, adherence, and retention in medical care. The study urges a contextualized understanding of the social challenges associated with TB/HIV healthcare and helps inform more patient-sensitive and socially responsive interventions against the co-epidemic

Paediatric chemoprophylaxis for child contacts of patients with drug-resistant tuberculosis: Are current guidelines effective in preventing disease?

The World Health Organization estimates that there were 480 000 new cases of multidrug-resistant tuberculosis (MDR-TB) in 2013. Alarmingly, 40% of MDR-TB cases for which second-line drug susceptibility test results were reported originated in South Africa (SA). This has important implications in vulnerable pop- ulations, such as children, where infection with drug-resistant strains of TB are usually attributable to transmission rather than acquisition of resistance.

Addressing challenges in scaling up TB and HIV treatment integration in rural primary healthcare clinics in South Africa (SUTHI): a cluster randomized controlled trial protocol

Background A large and compelling clinical evidence base has shown that integrated TB and HIV services leads to reduction in human immunodeficiency virus (HIV)- and tuberculosis (TB)-associated mortality and morbidity. Despite official policies and guidelines recommending TB and HIV care integration, its poor implementation has resulted in TB and HIV remaining the commonest causes of death in several countries in sub-Saharan Africa, including South Africa. This study aims to reduce mortality due to TB-HIV co-infection through a quality improvement strategy for scaling up of TB and HIV treatment integration in rural primary healthcare clinics in South Africa. Methods The study is designed as an open-label cluster randomized controlled trial. Sixteen clinic supervisors who oversee 40 primary health care (PHC) clinics in two rural districts of KwaZulu-Natal, South Africa will be randomized to either the control group (provision of standard government guidance for TB-HIV integration) or the intervention group (provision of standard government guidance with active enhancement of TB-HIV care integration through a quality improvement approach). The primary outcome is all-cause mortality among TB-HIV patients. Secondary outcomes include time to antiretroviral therapy (ART) initiation among TB-HIV co-infected patients, as well as TB and HIV treatment outcomes at 12 months. In addition, factors that may affect the intervention, such as conditions in the clinic and staff availability, will be closely monitored and documented. Discussion This study has the potential to address the gap between the establishment of TB-HIV care integration policies and guidelines and their implementation in the provision of integrated care in PHC clinics. If successful, an evidence-based intervention comprising change ideas, tools, and approaches for quality improvement could inform the future rapid scale up, implementation, and sustainability of improved TB-HIV integration across sub-Sahara Africa and other resource-constrained settings. Trial registration Clinicaltrials.gov, NCT02654613. Registered 01 June 2015