Abstract:

Background: Blood culture is the gold standard for diagnosing bloodstream infections, but with conventional blood culture techniques, it takes more than 72 hours for results to reach clinicians. To improve the management of pediatric patients, preliminary Gram stain results are often provided to clinicians within 18 to 24 hours while waiting for the final blood culture results. However, the utility of primary Gram stain in predicting the possible causative agent is not well established. This study provided data on the utility of Gram stain results in predicting the possible causative agents of bloodstream infections in children at different incubation times (8, 24, and 72 hours) at Sekou-Toure Regional Referral Hospital.

Methodology: A hospital-based, descriptive cross-sectional study was conducted at Sekou-Toure Reginal Referral Hospital from 18th May to 31st July 2024. A total of 302 blood culture samples were collected from children with clinical features suggestive of bloodstream infections. Conventional blood culture method using in house prepared media with slight modification on initial time of blind subculture and primary Gram stain were used to isolate possible causative agent. Demographical data, clinical information, and laboratory findings were collected using a structured data extraction sheet. Data cleaning and coding performed in Microsoft excel sheet. Data were analyzed by using a two-by-two table.

Results: A total of 288, 277 and 272 blood culture samples were analyzed at 8hrs, 24hrs and 72hrs respectively. The study excluded 14, 25 and 30 samples contaminated at 8hrs, 24hrs and 72hrs respectively. Out of the blood culture samples analyzed at each timeframe, positive Gram stains were 39, 69, and 84, at 8hrs, 24hrs and 72hrs respectively. A positive blood culture was 46, 77, and 91, at 8 hours, 24 hours, and 72 hours respectively. Utility of Gram stain in detection of blood culture at 8hrs, 24hrs and 72hrs was showed to be sensitivity (80.4%, 85.7% and 92.3%), specificity (99.1%, 98.5% and 100%), positive productive value (94.9%, 95.7% and 100%) and negative predictive value (96.4%, 94.7% and 96.3%), respectively.

Conclusion and recommendation: The utility of Gram stain in detection of blood stream infection among pediatric patients increases with increase in preliminary incubation time. The primary Gram stain is sensitive and has high specificity in diagnosis of bloodstream infection. The study recommend primary gram stain to be conducted within 8 hours of preliminary incubation.