Blood culture time to positivity in pediatric patients with bloodstream infection in rural Gambia

Abstract

Objectives: There is a lack of data on the time to blood culture positivity (TTP) in pediatric populations in low-income countries. We aimed to assess the host and pathogen factors associated with TTP in children aged under 5 years in rural Gambia.

Methods: Between September 2019 and December 2023, we collected blood cultures from children under 5 years with suspected bloodstream infections. We determined the TTP from the time of culture incubation to when bacterial growth was first detected.

Results: Overall, 547 invasive bacteria pathogens were evaluated. The median TTP was 19.2 hours and 70%, 76%, 89%, and 96% of cases had TTP at 24, 36, 48, and 72 hours, respectively. Streptococcus pneumoniae had the shortest median TTP (17.4 hours), whereas Neisseria species had the longest (45 hours). TTP was dependent on the pathogen and independent of age, sex, temperature, clinical outcome, nutritional status, and length of hospital stay. Gram-positive bacteria had shorter TTP than gram-negative bacteria (18.6 vs 19.6 hours, P < 0.01).

Conclusions: In rural Gambia, most blood cultures from pediatric patients would turn positive within 48 hours of incubation. A maximum of 48 hours of observation after the commencement of antibiotic therapy in hospitalized children may be sufficient for clinicians to receive feedback on blood culture results.

Keywords: Blood cultures; Bloodstream infections; Children; The Gambia; Time-to-positivity.

Figure 1

The distribution and proportions of positive blood cultures and TTP. (a) The distribution of the overall number of positive blood cultures and TTP (with median TTP shown as a dashed line). (b) The proportion of positive blood culture with TTP. TTP, time to positivity.

Figure 2

Top 10 pathogens and median time to positivity. Bars show the estimated median time to positivity in hours. Error bars show interquartile ranges (interquartile range).