Recovery of anaerobic, facultative, and aerobic bacteria from clinical specimens in three anaerobic transport systems

Abstract

With aspirated specimens from clinical infections, we evaluated the recovery of anaerobic, aerobic, and facultative bacteria in three widely used transport systems: (i) aspirated fluid in a gassed-out tube (FGT), (ii) swab in modified Cary and Blair transport medium (SCB), and (iii) swab in a gassed-out tube (SGT). Transport tubes were held at 25 degrees C and semiquantitatively sampled at 0, 2, 24, and 48 h. Twenty-five clinical specimens yielded 75 anaerobic strains and 43 isolates of facultative and 3 of aerobic bacteria. Only one anaerobic isolate was not recovered in the first 24 h, and then, only in the SGT. At 48 h, 73 anaerobic strains (97%) were recovered in the FGT, 69 (92%) in the SCB, and 64 (85%) in the SGT. Two problems hindered the recovery of anaerobes in the SCB and SGT systems: first die-off of organisms, as evidenced by a decrease in colony-forming units of 20 strains (27%) in the SCB and 25 strains (33%) in the SGT, as compared with 7 strains (9%) in the FGT, over 48 h; and second, overgrowth of facultative bacteria, more frequent with SCB and SGT. The FGT method was clearly superior at 48 h to the SCB and SGT systems in this study and is recommended as the preferred method for transporting specimens for anaerobic culture.

Antimicrobial resistance in patients with odontogenic infections: A systematic scoping review of prospective and experimental studies

“…showed low resistance to moxifloxacin ( 10 ), while one prospective study described that S. viridans and K. pneumoniae displayed intermediate susceptibility and high resistance to this antimicrobial, respectively ( 27 ). As has been described, methodological and geographical differences in research evaluating bacterial resistance may support these results ( 7 , 38 ).…”

Establishment of Multiplex qPCR System for Common Pathogens and Its Application In the Detection of Fracture Related Infections

“…11,21,30 Swab cultures and sonication uid are considered susceptible to various problems, including contamination risk, low specimen volume for culture, and inhibition of pathogen growth. 31,32 Previous studies have reported limited performance of swab cultures compared to tissue cultures for diagnosing orthopaedic implant-related infections. 33,34 Considering that contamination can signi cantly reduce the speci city of detection, we chose tissue sampling for culture and PCR instead of swab or sonication uid.…”