Merve GÜRLER, Ahmet DEMİRHAN, Ceydanur AHATA, Dilara KARAKUŞ, Esra ÇORUK, Gökçe Deniz ESER, Oğuzhan YILMAZ, Ayşegül BİNAY, Beyza Doğanay ERDOĞAN, Zeynep Ceren KARAHAN
Journal of Basic and Clinical Health Sciences - 2026;10(3):342-349
Purpose: Blood culture (BC) remains the gold standard for detecting bloodstream infections. Given the typically low microbial load in adult bacteremia, both the volume of blood sampled and proper collection techniques are essential for diagnostic accuracy. This study aimed to evaluate BC collection practices in adult patients, focusing on blood volume adequacy, departmental variation, and the influence of pre-analytical factors on culture yield. Material and Methods: This retrospective study included all aerobic and anaerobic BC bottles submitted from adult patients to the Microbiology Laboratory of Ankara University Faculty of Medicine between January 10 and April 30, 2022. Blood volume per bottle was visually measured post-incubation. Demographic and clinical data were extracted from hospital records. Results: A total of 4,695 BC bottles representing 1,463 episodes from 712 adult patients were analyzed. Only 47% of episodes met the recommended standard of at least two sets per episode. Approximately one-fourth of bottles were filled within the optimal range, and overfilling was more common than underfilling. Crude positivity appeared higher among overfilled bottles; however, after stratification by sampling site, overfilled bottles showed lower positivity proportions within both central venous catheter (CVC)-derived and peripheral samples. Patients with malignancy had higher blood volumes, whereas those with neuropsychiatric conditions or recent surgery had lower volumes. Blood volumes were substantially lower in the intensive care unit and the emergency department. CVC sampling was associated with higher blood volumes, although optimal filling remained infrequent. Conclusion: Adherence to recommended BC sampling standards, particularly regarding blood volume and the number of sets, remains suboptimal across clinical settings. Targeted interventions addressing pre-analytical errors and departmental variation may improve diagnostic performance in suspected bloodstream infections.
