BackgroundBlood culture diagnostics are a critical tool for sepsis management and antimicrobial resistance (AMR) surveillance. A baseline study was conducted to assess existing sepsis case finding, blood culture diagnostics and antimicrobial susceptibility testing (AST) at secondary health care facilities to inform the development of diagnostic stewardship improvement strategies in Nigeria.MethodsA cross-sectional online survey was conducted among 25 public secondary health care facilities in Abuja, FCT and Lagos State in Nigeria to evaluate the capacity for pathogen identification and AST. Following this, data were prospectively extracted on all patients with suspected sepsis from electronic medical records at two facilities in Abuja from October 2020 to May 2021 to further assess practices concerning sepsis case-finding, clinical examination findings, samples requested, and laboratory test results. Data were descriptively analysed, and a multivariate logistic regression analysis was conducted to determine factors associated with blood culture requests among suspected sepsis patients.ResultsIn the online survey, 32% (8/25) of facilities reported performing routine blood cultures. Only one had access to a clinical microbiologist, and 28% (7/25) and 4% (1/25) used standard bacterial organisms for quality control of media and quality control strains for AST, respectively. At the two facilities where data abstraction was performed, 7.1% (2924/41066) of patients were found to have suspected sepsis. A majority of the suspected sepsis patients came from the paediatrics department and were outpatients, and the median age was two years. Most did not have vital signs and major foci of infection documented. Blood cultures were only requested for 2.7% (80/2924) of patients, of which twelve were positive for bacteria, mainly Staphylococcus aureus. No clinical breakpoints were used for AST. Inpatients (adjusted odds ratio [aOR]:7.5, 95% CI:4.6 – 12.3) and patients from the urban health care facility (aOR:16.9, 95% CI:8.1 – 41.4) were significantly more likely to have a blood culture requested.ConclusionLow blood culture utilisation remains a key challenge in Nigeria. This has implications for patient care. AMR surveillance and antibiotics use. Diagnostic stewardship strategies should focus on improving access to clinical microbiology expertise, practical guidance on sepsis case finding and improving blood culture utilisation and diagnostics.