Remote Ischaemic Conditioning in STEMI Patients in Sub-Saharan AFRICA: Rationale and Study Design for the RIC-AFRICA Trial.

PURPOSE: Despite evidence of myocardial infarct size reduction in animal studies, remote ischaemic conditioning (RIC) failed to improve clinical outcomes in the large CONDI-2/ERIC-PPCI trial. Potential reasons include that the predominantly low-risk study participants all received timely optimal reperfusion therapy by primary percutaneous coronary intervention (PPCI). Whether RIC can improve clinical outcomes in higher-risk STEMI patients in environments with poor access to early reperfusion or PPCI will be investigated in the RIC-AFRICA trial. METHODS: The RIC-AFRICA study is a sub-Saharan African multi-centre, randomized, double-blind, sham-controlled clinical trial designed to test the impact of RIC on the composite endpoint of 30-day mortality and heart failure in 1200 adult STEMI patients without access to PPCI. Randomized participants will be stratified by whether or not they receive thrombolytic therapy within 12 h or arrive outside the thrombolytic window (12-24 h). Participants will receive either RIC (four 5-min cycles of inflation [20 mmHg above systolic blood pressure] and deflation of an automated blood pressure cuff placed on the upper arm) or sham control (similar protocol but with low-pressure inflation of 20 mmHg and deflation) within 1 h of thrombolysis and applied daily for the next 2 days. STEMI patients arriving greater than 24 h after chest pain but within 72 h will be recruited to participate in a concurrently running independent observational arm. CONCLUSION: The RIC-AFRICA trial will determine whether RIC can reduce rates of death and heart failure in higher-risk sub-optimally reperfused STEMI patients, thereby providing a low-cost, non-invasive therapy for improving health outcomes.

Brief Report: Changing Characteristics Among In-Hospital HIV Deaths: An 11-Year Retrospective Review of a Regional Hospital in South Africa.

BACKGROUND: Elevated HIV-associated mortality persists, despite a notable decline with the expansion of antiretroviral therapy (ART). In South Africa, the relative majority of deaths occur in health facilities, providing an opportunity to track decedent characteristics. SETTING: We analyzed data from 14,870 adult patients who died between 2008 and 2018 at Klerksdorp/Tshepong Hospital Complex in South Africa. METHODS: Recorded data included demographics, causes of death, HIV status, ART, and tuberculosis (TB) history. We present summary statistics and results from linear, log-binomial, and multinomial regressions to quantify changes over time. RESULTS: Over the study period, the median age of decedents with HIV in the hospital increased from 39.3 to 43.4 years, and there was a switch to male predominance (46%-54%). Those who died at a younger age (<40 years) remained more likely to be HIV-positive than the older age group, despite the overall proportion of HIV-positivity decreasing over time. The proportion of decedents with HIV ever started on ART increased from 21% to 67%. The proportion of HIV patients dying from TB and AIDS-defining illnesses decreased from 31% to 22%. CONCLUSIONS: We noted a shift in deaths over time to more men and older individuals, whereas the burden of HIV was heaviest on the younger age groups. Advanced HIV disease remained an important cause of mortality. We also observed an increase in less-traditional opportunistic illnesses among those with HIV, including malignancy, cardiovascular disease, and kidney disease. The high proportion of patients on ART who died prematurely requires further research and interventions.

Emergence of increased resistance and extensively drug-resistant tuberculosis despite treatment adherence, South Africa.

We investigated the emergence and evolution of drug-resistant tuberculosis (TB) in an HIV co-infected population at a South African gold mine with a well-functioning TB control program. Of 128 patients with drug-resistant TB diagnosed during January 2003-November 2005, a total of 77 had multidrug-resistant (MDR) TB, 26 had pre-extensively drug-resistant TB (XDR TB), and 5 had XDR TB. Genotyping suggested ongoing transmission of drug-resistant TB, and contact tracing among case-patients in the largest cluster demonstrated multiple possible points of contact. Phylogenetic analysis demonstrated stepwise evolution of drug resistance, despite stringent treatment adherence. These findings suggested that existing TB control measures were inadequate to control the spread of drug-resistant TB in this HIV co-infected population. Diagnosis delay and inappropriate therapy facilitated disease transmission and drug-resistance. These data call for improved infection control measures, implementation of rapid diagnostics, enhanced active screening strategies, and pharmacokinetic studies to determine optimal dosages and treatment regimens.

Genomic analysis identifies targets of convergent positive selection in drug-resistant Mycobacterium tuberculosis.

M. tuberculosis is evolving antibiotic resistance, threatening attempts at tuberculosis epidemic control. Mechanisms of resistance, including genetic changes favored by selection in resistant isolates, are incompletely understood. Using 116 newly sequenced and 7 previously sequenced M. tuberculosis whole genomes, we identified genome-wide signatures of positive selection specific to the 47 drug-resistant strains. By searching for convergent evolution--the independent fixation of mutations in the same nucleotide position or gene--we recovered 100% of a set of known resistance markers. We also found evidence of positive selection in an additional 39 genomic regions in resistant isolates. These regions encode components in cell wall biosynthesis, transcriptional regulation and DNA repair pathways. Mutations in these regions could directly confer resistance or compensate for fitness costs associated with resistance. Functional genetic analysis of mutations in one gene, ponA1, demonstrated an in vitro growth advantage in the presence of the drug rifampicin.