Aetiology and prognosis of community-acquired pneumonia at the Adult University Teaching Hospital in Zambia.

BACKGROUND: Community-acquired pneumonia (CAP) is a frequent cause of death worldwide, and in sub-Saharan Africa particularly. Human immunodeficiency virus infection (HIV) and tuberculosis (TB) influence pathogen distribution in patients with CAP. Previous studies in sub-Saharan Africa have shown different frequencies of respiratory pathogens and antibiotic susceptibility compared to studies outside Africa. This study aimed to investigate the aetiology, presentation, and treatment outcomes of community-acquired pneumonia in adults at the University Teaching Hospital in Lusaka, Zambia. MATERIALS AND METHODS: Three-hundred-and-twenty-seven patients were enrolled at the University Teaching Hospital in Lusaka between March 2018 and December 2018. Clinical characteristics and laboratory data were collected. Sputum samples were tested by microscopy, other TB diagnostics, and bacterial cultures. RESULTS: The commonest presenting complaint was cough (96%), followed by chest pain (60.6%), fever (59.3%), and breathlessness (58.4%). The most common finding on auscultation of the lungs was chest crackles (51.7%). Seventy percent of the study participants had complaints lasting at least a week before enrolment. The prevalence of HIV was 71%. Sputum samples were tested for 286 patients. The diagnostic yield was 59%. The most common isolate was Mycobacterium tuberculosis (20%), followed by Candida species (18%), Klebsiella pneumoniae (12%), and Pseudomonas aeruginosa (7%). Streptococcus pneumoniae was isolated in only four patients. There were no statistically significant differences between the rates of specific pathogens identified in HIV-infected patients compared with the HIV-uninfected. Thirty-day mortality was 30%. Patients with TB had higher 30-day mortality than patients without TB (p = 0.047). CONCLUSION: Mycobacterium tuberculosis was the most common cause of CAP isolated in adults at the University Teaching Hospital in Lusaka, Zambia. Gram-negative organisms were frequently isolated. A high mortality rate was observed, as 30% of the followed-up study population had died after 30 days.

Insulin Resistance is Associated with Higher Plasma Viral Load Among HIV-Positive Adults Receiving Longer-Term (1 Year) Combination Antiretroviral Therapy (ART).

Background: As HIV-positive persons survive longer due to the success of combination antiretroviral therapy (ART) in decreasing mortality, the burden of non-communicable diseases including diabetes mellitus (DM) is anticipated to rise. HIV is characterized by systemic inflammations, markers of which decrease quickly following ART initiation, but typically do not completely normalize. Inflammation may be accompanied by insulin resistance (IR), and both are implicated in the pathogenesis of DM in HIV-positive individuals. Sub-Saharan Africa accounts for almost two-thirds of the global HIV burden but there are few reports of IR, DM and HIV in this region. We assessed the relationship between IR and viral suppression among HIV-positive adults in the Zambian national ART program. Methods: We conducted a cross-sectional survey evaluating HIV-positive adults that had received first line ART (usually TDF/FTC/EFV) for 12 months (± 3 months). Twenty clinics were sampled systematically based on the random starting-point, sampling interval and cumulative population size. Eligible patients had plasma viral load (VL), fasting insulin, and glucose performed. Insulin resistance was determined using Homeostatic model assessment (HOMA). We determined proportions for each outcome using linearized standard error 95% confidence intervals and summary estimates. Viral suppression was defined according to the detection threshold of<20 copies/mL and treatment failure was defined as VL>1,000 copies/mL. Results: Of 473 patients enrolled, 46.8% were male and 53.2% were female. 142 (30%) [95% CI: 0.26-0.34] had IR. Among those with IR, 55 (38.7%) were male whereas 87 (61.3%) were female (p value=0.104). 19% of individuals with IR had treatment failure compared to 5.7% without IR (p value<0.0001). 427 (90.3%) participants had treatment success (VL<1,000 copies/mL), and this was associated with a lower likelihood of IR (odds ratio (OR)=0.26 [0.14, 0.48], p value<0.0001). In addition, a significantly lower proportion of patients with IR were virologically suppressed at one-year compared to individuals without IR, 58% [0.54-0.70] versus 70% [0.65-0.75], respectively (p value=0.042). Conclusion: In Zambian adults on ART for a year, the development of insulin resistance was strongly associated with suboptimal HIV outcomes, specifically non-viral suppression and treatment failure. Further investigations are warranted to determine if this positive association between IR and VL is causally related, and if so in which direction.