BackgroundA well-established antimicrobial resistance (AMR) laboratory-based surveillance (LBS) is of utmost importance in a country like Zambia which bears a significant proportion of the world’s communicable disease burden. This study assessed the capacity of laboratories in selected hospitals to conduct AMR surveillance in Zambia.MethodsThis cross-sectional exploratory study was conducted among eight (8) purposively selected hospitals in Zambia between August 2023 and December 2023. Data were collected using the self-scoring Laboratory Assessment of Antibiotic Resistance Testing Capacity (LAARC) tool.FindingsOf the assessed facilities, none had full capacity to conduct AMR surveillance with varying capacities ranging from moderate [63% (5/8)] to low [38% (3/8)]. Some of the barriers of AMR-LBS were the lack of electronic laboratory information system (LIS) [63% (5/8)] and the lack of locally generated antibiograms [75% (6/8)]. Quality control for antimicrobial susceptibility testing (AST), pathogen identification and media preparation had the lowest overall score among all the facilities with a score of 14%, 20% and 44% respectively. The highest overall scores were in specimen processing (79%), data management (78%), specimen collection, transport, and management (71%) and safety (70%). Most facilities had standard operating procedures (SOPs) in place but lacked specimen-specific SOPs.ConclusionThe absence of laboratories with full capacity to conduct AMR surveillance hinders efforts to combat AMR and further complicates the treatment outcomes of infectious diseases. Establishing and strengthening LBS systems are essential in quantifying the burden of AMR and supporting the development of local antibiograms and treatment guidelines.

BackgroundCommunity-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 methodsThree-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.ResultsThe 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).ConclusionMycobacterium 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.

Abstract Introduction Healthcare workers (HCWs) in Zambia have become infected with SARS-CoV-2, the virus that causes coronavirus disease (COVID-19). However, SARS-CoV-2 prevalence among HCWs is not known in Zambia. Methods We conducted a cross-sectional SARS-CoV-2 prevalence survey among Zambian HCWs in twenty health facilities in six districts in July 2020. Participants were tested for SARS-CoV-2 infection using polymerase chain reaction (PCR) and for SARS-CoV-2 antibodies using enzyme-linked immunosorbent assay (ELISA). Prevalence estimates and 95% confidence intervals (CIs), adjusted for health facility clustering, were calculated for each test separately and a combined measure for those who had PCR and ELISA performed. Results In total, 660 HCWs participated in the study, with 450 (68.2%) providing nasopharyngeal swab for PCR and 575 (87.1%) providing a blood specimen for ELISA. Sixty-six percent of participants were females and the median age was 31.5 years (interquartile range 26.2–39.8 years). The overall prevalence of the combined measure was 9.3% (95% CI 3.8%–14.7%). PCR-positive prevalence of SARS-CoV-2 was 6.6% (95% CI 2.0%–11.1%) and ELISA-positive prevalence was 2.2% (95% CI 0.5%–3.9%). Conclusions SARS-CoV-2 prevalence among HCWs was similar to a population-based estimate (10.6%) during a period of community transmission in Zambia. Public health measures such as establishing COVID-19 treatment centers before the first cases, screening for COVID-19 symptoms among patients accessing health facilities, infection prevention and control trainings, and targeted distribution of personal protective equipment based on exposure risk might have prevented increased SARS-CoV-2 transmission among Zambian HCWs.

BACKGROUND:Combination antifungal therapy (amphotericin B deoxycholate and flucytosine) is the recommended treatment for cryptococcal meningitis but has not been shown to reduce mortality, as compared with amphotericin B alone. We performed a randomized, controlled trial to determine whether combining flucytosine or high-dose fluconazole with high-dose amphotericin B improved survival at 14 and 70 days.METHODS:We conducted a randomized, three-group, open-label trial of induction therapy for cryptococcal meningitis in patients with human immunodeficiency virus infection. All patients received amphotericin B at a dose of 1 mg per kilogram of body weight per day; patients in group 1 were treated for 4 weeks, and those in groups 2 and 3 for 2 weeks. Patients in group 2 concurrently received flucytosine at a dose of 100 mg per kilogram per day for 2 weeks, and those in group 3 concurrently received fluconazole at a dose of 400 mg twice daily for 2 weeks.RESULTS:A total of 299 patients were enrolled. Fewer deaths occurred by days 14 and 70 among patients receiving amphotericin B and flucytosine than among those receiving amphotericin B alone (15 vs. 25 deaths by day 14; hazard ratio, 0.57; 95% confidence interval [CI], 0.30 to 1.08; unadjusted P=0.08; and 30 vs. 44 deaths by day 70; hazard ratio, 0.61; 95% CI, 0.39 to 0.97; unadjusted P=0.04). Combination therapy with fluconazole had no significant effect on survival, as compared with monotherapy (hazard ratio for death by 14 days, 0.78; 95% CI, 0.44 to 1.41; P=0.42; hazard ratio for death by 70 days, 0.71; 95% CI, 0.45 to 1.11; P=0.13). Amphotericin B plus flucytosine was associated with significantly increased rates of yeast clearance from cerebrospinal fluid (-0.42 log10 colony-forming units [CFU] per milliliter per day vs. -0.31 and -0.32 log10 CFU per milliliter per day in groups 1 and 3, respectively; P<0.001 for both comparisons). Rates of adverse events were similar in all groups, although neutropenia was more frequent in patients receiving a combination therapy.CONCLUSIONS:Amphotericin B plus flucytosine, as compared with amphotericin B alone, is associated with improved survival among patients with cryptococcal meningitis. A survival benefit of amphotericin B plus fluconazole was not found. (Funded by the Wellcome Trust and the British Infection Society; Controlled-Trials.com number, ISRCTN95123928.).

ObjectiveOur objective was to examine the role of mitochondrial uncoupling protein‐2 (UCP2), highly expressed in lung fibroblasts of patients with idiopathic pulmonary fibrosis (IPF), in mediating mitochondrial dysfunction, fibroblast senescence and myofibroblast differentiation in age‐related pathologic fibrosis.MethodsWe studied tissues and fibroblasts obtained from lung explants of IPF patients and utilized the murine model of lung fibrosis and resolution following bleomycin‐induced injury. We silenced UCP2 expression using siRNA in vitro and in vivo. Specific endpoints were analyzed by RT‐PCR, SDS‐PAGE western blotting, immunofluorescence, flow cytometry, mass spectrometry and extracellular flux analysis.ResultsUCP2 gene expression was increased in lungs (whole lung lysates as well as fibroblasts) of IPF patients compared to those without IPF; in particular, mesenchymal stromal cells derived from bronchoalveolar lavage of patients with rapidly progressive clinical course had higher UCP2 expression compared to those with a slower course. Human lung fibroblasts undergoing replicative senescence expressed high levels of UCP2. Lung fibroblasts from aged mice expressed higher UCP2 than younger counterparts, more pronounced after bleomycin‐induced lung injury. UCP2 silencing in IPF fibroblasts decreased pro‐fibrotic markers such as α‐SMA and collagen; this was associated with enhanced mitochondrial biogenesis, decreased mitochondrial ROS (superoxide and hydrogen peroxide), increased ATP‐linked oxygen consumption and decreased aerobic glycolysis. In addition, UCP2 silencing induced a decrease in senescence markers and decreased expression of senescence‐associated secretory phenotype (SASP) genes. In aged mice after bleomycin injury, therapeutic oro‐tracheal administration of UCP2 siRNA resulted in decreased lung collagen and fibrotic remodeling, indicating enhanced resolution capacity.ConclusionOur results suggest that expression of mitochondrial UCP2 in lung fibroblasts increases with age. UCP2 is highly expressed in lung fibroblasts of patients with IPF, more so in those with rapidly progressive clinical course; UCP2 promotes myofibroblast senescence and impairs resolution of bleomycin injury‐induced fibrosis in aged mice. Further studies are warranted to study the link between cellular aging and UCP2, and the therapeutic potential of targeting UCP2 in age‐related fibrotic disorders such as IPF.Support or Funding InformationNIH grants K08 HL135399 (SR); P01 HL114470 and R01 AG046210 (VJT), VA Merit Award I01BX003056 (VJT) Schematic showing the role of UCP2 in fibroblast (patho)biologyimageSchematic showing the role of UCP2 in fibroblast (patho)biologyThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Exosomes are nano-sized, membrane-bound vesicles released from cells that transport cargo including DNA, RNA, and proteins, between cells as a form of intercellular communication. In addition to their role in intercellular communication, exosomes are beginning to be appreciated as agents of immunoregulation that can modulate antigen presentation, immune activation, suppression, and surveillance. This article summarizes how these multifaceted functions of exosomes may promote development and/or progression of chronic inflammatory lung diseases including asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. The potential of exosomes as a novel therapeutic is also discussed.

Background: Mycobacterium tuberculosis (TB) remains a leading cause of mortality and morbidity worldwide, including Zambia, especially among those infected with the Human Immunodeficiency Virus (HIV). Both kidney dysfunction and TB have been shown to be highly prevalent among hospitalised HIV infected patients. Little is known about how TB and kidney dysfunction impact each other in HIV patients, and whether there is any association between the occurrence of kidney dysfunction and active TB infection in this population. This study was aimed at determining the prevalence and risk factors of active TB infection in HIV positive patients with and without kidney dysfunction. Methods: This was an analytical cross-sectional study. Using simple random sampling, HIV positive patients on the medical wards were recruited in two arms (74 with & 59 without kidney dysfunction). Urine Lipoarabinomannan (LAM), TB blood culture, sputum culture and genexpert MTB/Rif were used for TB diagnosis. Data was analysed using STATA version 13. Results: TB prevalence in all HIV positive hospitalized patients was 45%, and more prevalent in the kidney disease than non-kidney disease group (54% vs 35.59%; p=0.034). TB diagnosis pick up was comparable in the kidney disease and the non-kidney disease group using urine LAM and blood culture at 31.1% vs 22.2% and 8.9% vs 3.1% respectively, but lower using sputum culture; 12.5% vs 24.1%. Among kidney disease patients, a higher CD4 count > 200cells/μl was protective for active TB (P = 0.011). Severe immunosuppression (CD4 count < 200cells/μl) was 18.64% higher in the kidney dysfunction group compared to the non-kidney disease group (P=0.026). The only factor associated with active TB was male gender (P = 0.029); while Proteinuria in a TB patient was strongly associated with kidney disease (P < 0.001). Patients with WHO stage III/IV were likely to present with TB in both groups (P=0.004, 95% CI 1.47 - 7.20). Kidney dysfunction severity (measured by estimated glomerular filtration rate), age, antiretroviral therapy status and duration on combination antiretroviral therapy, history of TB contact and current cough, had no significant association with active TB in the two groups. Conclusion: Patients with kidney disease are more likely to present with active TB infection than HIV infected patients with no kidney disease. Among patients with active TB, urinalysis can help predict renal dysfunction; while determinants of active TB in the general population are not similar to those in kidney disease patients.