Evaluation of Quality Assurance Indicators and Contamination Rate in Blood Culture

Abstract

Objective: Blood culture are of vital importance in patient follow-up, as they enable the identification and production of sepsis causative microorganisms, initiate antibiotic treatment in a timely manner and reduce mortality and morbidity. In this study, it is aimed to evaluate the microorganisms grown in the automated blood culture in the microbiology laboratory of the hospital in terms of quality indicators. Methods: In this study, microorganisms grown from automated blood culture BACTEC-9120 (Becton Dickinson, USA) system from the blood culture samples sent to Duzce University Medical Microbiology Laboratory were evaluated retrospectively. For this purpose, the rejection and contamination rate of the samples for which blood culture was requested, the result of Gram staining-final identification compliance, the number of samples sent from a single bottle, and the growth times of microorganisms after incubation were determined. Results: 5037 blood culture samples were sent to the laboratory from various clinics. 1.7% of these samples were rejected as inappropriate samples. Gram stain-final identification compatibility of blood cultures was investigated and it was determined as 97.8%. The single bottle number of the samples sent was found to be 511. For the 5037 samples included in the study, growth was detected in 20.7%, of which 10.2% were considered as contaminants. In our study, the average breeding time of the factors examined for breeding time was determined to be 30.29 hours. Conclusions: As conclusion, there is no gold standard to distinguish true pathogens from contaminant agents in blood cultures.