Evaluation of blood cultures in anaerobiosis

BACKGROUND: The rate of processed blood cultures from anaerobic bottles was checked and the number of isolates from anaerobic microorganisms and other non anaerobic ones from processed bottles was established. Next, we studied the relationship between bacteremia caused by anaerobic organisms and the clinical history. METHODS: A total of 3.540 blood cultures have been checked for a period of 21 months; all of them were processed using Bactec NR 730 system. Those patients suffering bacteremia caused by anaerobic microorganisms had their medical histories revised. There is neither Gynecology nor Pediatrics Services at our Medical Center. RESULTS: Eleven episodes of bacteremias caused by anaerobic microorganisms have been detected since we started our research 21 months ago. Three aerobic microorganisms grew only in the two processed bottles in anaerobiosis, being their respective aerobic cultures negative. In all cases of bacteremia caused by anaerobic bacteria, the clinical history was compatible with this infection. CONCLUSIONS: We consider it is worth keeping the anaerobic bottles, because the number of anaerobic microorganisms isolates is considerable and clinically significant. A 2.76% incidence, where there is not gynecologist hospitalization, seems to be a high and relevant one. An alternative approach is to perform them only under certain clinical circumstances, although the process of collecting samples would make it a difficult task.