Mortality associated with third-generation cephalosporin resistance in Enterobacterales bloodstream infections at eight sub-Saharan African hospitals (MBIRA): a prospective cohort study.

BACKGROUND: Bacteria of the order Enterobacterales are common pathogens causing bloodstream infections in sub-Saharan Africa and are frequently resistant to third-generation cephalosporin antibiotics. Although third-generation cephalosporin resistance is believed to lead to adverse outcomes, this relationship is difficult to quantify and has rarely been studied in this region. We aimed to measure the effects associated with resistance to third-generation cephalosporins in hospitalised patients with Enterobacterales bloodstream infection in Africa. METHODS: We conducted a prospective, matched, parallel cohort study at eight hospitals across sub-Saharan Africa. We recruited consecutive patients of all age groups with laboratory-confirmed Enterobacterales bloodstream infection and matched them to at least one patient without bloodstream infection on the basis of age group, hospital ward, and admission date. Date of infection onset (and enrolment) was defined as the day of blood sample collection for culturing. Patients infected with bacteria with a cefotaxime minimum inhibitory concentration of 1 mg/L or lower were included in the third-generation cephalosporin-susceptible (3GC-S) cohort, and the remainder were included in the third-generation cephalosporin-resistant (3GC-R) cohort. The primary outcomes were in-hospital death and death within 30 days of enrolment. We used adjusted multivariable regression models to first compare patients with bloodstream infection against matched patients within the 3GC-S and 3GC-R cohorts, then compared estimates between cohorts. FINDINGS: Between Nov 1, 2020, and Jan 31, 2022, we recruited 878 patients with Enterobacterales bloodstream infection (221 [25·2%] to the 3GC-S cohort and 657 [74·8%] to the 3GC-R cohort) and 1634 matched patients (420 [25·7%] and 1214 [74·3%], respectively). 502 (57·2%) bloodstream infections occurred in neonates and infants (age 0-364 days). Klebsiella pneumoniae (393 [44·8%] infections) and Escherichia coli (224 [25·5%] infections) were the most common Enterobacterales species identified. The proportion of patients who died in hospital was higher in patients with bloodstream infection than in matched controls in the 3GC-S cohort (62 [28·1%] of 221 vs 22 [5·2%] of 420; cause-specific hazard ratio 6·79 [95% CI 4·06-11·37] from Cox model) and the 3GC-R cohort (244 [37·1%] of 657 vs 115 [9·5%] of 1214; 5·01 [3·96-6·32]). The ratio of these cause-specific hazard ratios showed no significant difference in risk of in-hospital death in the 3GC-R cohort versus the 3GC-S cohort (0·74 [0·42-1·30]). The ratio of relative risk of death within 30 days (0·82 [95% CI 0·53-1·27]) also indicated no difference between the cohorts. INTERPRETATION: Patients with bloodstream infections with Enterobacterales bacteria either resistant or susceptible to third-generation cephalosporins had increased mortality compared with uninfected matched patients, with no differential effect related to third-generation cephalosporin-resistance status. However, this finding does not account for time to appropriate antibiotic treatment, which remains clinically important to optimise. Measures to prevent transmission of Enterobacterales could reduce bloodstream infection-associated mortality from both drug-resistant and drug-susceptible bacterial strains in Africa. FUNDING: Bill & Melinda Gates Foundation.

Circumstances for treatment and control of invasive Enterobacterales infections in eight hospitals across sub-Saharan Africa: a cross-sectional study.

Background: Bloodstream infections caused by Enterobacterales show high frequency of antimicrobial resistance (AMR) in many Low- and Middle-Income Countries. We aimed to describe the variation in circumstances for management of such resistant infections in a group of African public-sector hospitals participating in a major research study. Methods: We gathered data from eight hospitals across sub-Saharan Africa to describe hospital services, infection prevention and antibiotic stewardship activities, using two WHO-generated tools. We collected monthly cross-sectional data on availability of antibiotics in the hospital pharmacies for bloodstream infections caused by Enterobacterales. We compared the availability of these antibiotics to actual patient-level use of antibiotics in confirmed Enterobacterales bloodstream infections (BSI). Results: Hospital circumstances for institutional management of resistant BSI varied markedly. This included self-evaluated infection prevention level (WHO-IPCAF score: median 428, range 155 to 687.5) and antibiotic stewardship activities (WHO stewardship toolkit questions: median 14.5, range 2 to 23). These results did not correlate with national income levels. Across all sites, ceftriaxone and ciprofloxacin were the most consistently available antibiotic agents, followed by amoxicillin, co-amoxiclav, gentamicin and co-trimoxazole. There was substantial variation in the availability of some antibiotics, especially carbapenems, amikacin and piperacillin-tazobactam with degree of access linked to national income level. Investigators described out-of-pocket payments for access to additional antibiotics at 7/8 sites. The in-pharmacy availability of antibiotics correlated well with actual use of antibiotics for treating BSI patients. Conclusions: There was wide variation between these African hospitals for a range of important circumstances relating to treatment and control of severe bacterial infections, though these did not all correspond to national income level. For most antibiotics, patient-level use reflected in-hospital drug availability, suggesting external antibiotics supply was infrequent. Antimicrobial resistant bacterial infections could plausibly show different clinical impacts across sub-Saharan Africa due to this contextual variation.

The CINAMR (Clinical Information Network-Antimicrobial Resistance) Project: A pilot microbial surveillance using hospitals linked to regional laboratories in Kenya: Study Protocol.

Background: Antimicrobial resistance (AMR) is a global threat and is thought to be acute in low-and middle-income country (LMIC) settings, including in Kenya, but there is limited unbiased surveillance that can provide reliable estimates of its burden. Current efforts to build capacity for microbiology testing in Kenya are unlikely to result in systematic routine microbiological testing in the near term. Therefore, there is little prospect for microbiological support to inform clinical diagnoses nor for indicating the burden of AMR and for guiding empirical choice of antibiotics. Objective: We aim to build on an existing collaboration, the Clinical Information Network (CIN), to pilot microbiological surveillance using a 'hub-and-spoke' model where selected hospitals are linked to high quality microbiology research laboratories. Methods: Children admitted to paediatric wards of 12 participating hospitals will have a sample taken for blood culture at admission before antibiotics are started. Indication for blood culture will be a clinician's prescription of antibiotics. Samples will then be transported daily to the research laboratories for culture and antibiotic susceptibility testing and results relayed back to clinicians for patient management. The surveillance will take place for 6 months in each hospital. Separately, we shall conduct semi-structured interviews with frontline health workers to explore the feasibility and utility of this approach. We will also seek to understand how the availability of microbiology results might inform antibiotic stewardship, and as an interim step to the development of better national or regional laboratories linked to routine surveillance. Conclusions: If feasible, this approach is less costly and periodic 'hub-and-spoke' surveillance can be used to track AMR trends and to broadly guide empirical antibiotic guidance meaning it is likely to be more sustainable than establishing functional microbiological facilities in each hospital in a LMIC setting.