Evaluation of blood culture systems for detection of the intestinal spirochaete Brachyspira (Serpulina) pilosicoli in human blood.
The anaerobic intestinal spirochaete Brachyspira (Serpulina) pilosicoli has been isolated from the bloodstream of French patients by manual blood culture systems. The purpose of this study was to determine whether the automated and manual blood culture systems used in Australia are suitable for growth and detection of this organism. Strains of B. pilosicoli were added to human blood to give concentrations ranging from 1 x 10(4) to 1 x 10(1) spirochaetes/ml and 10-ml volumes were inoculated into the media. Three strains of B. pilosicoli grew slowly in all manual Hemoline and BBL Septi-Chek formulations tested. Subcultures taken between 2 and 10 days after inoculation yielded growth only after incubation for a further 5-8 days. Growth and automated detection were achieved in the BACTEC system with Anaerobic/F medium with or without Fastidious Organism Supplement. Minimum time to signal for nine strains varied between 5.6 and 14.9 days, with a minimum concentration of 10(1) spirochaetes/ml of blood being detected. None of nine strains gave a positive signal in the BacT/Alert system when FAN Anaerobic culture bottles were used; however, four strains were detected by subculture taken at 7 or 14 days after inoculation. When Anaerobic medium was used in the BacT/Alert system, two of three strains gave a signal and the other strain grew and was detected by subculture. Spirochaetaemias caused by B. pilosicoli may be unrecognised because detection time by the signal or subculture exceeds 5 days.
Brooke
C Josephine
CJ
Margawani
K Rini
KR
Pearson
Alayne K
AK
Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150, *Division of Microbiology and Infectious Diseases, Western Australian Centre of Pathology and Medical Research, Nedlands WA 6009 and †Department of Microbiology, University of Western Australia, Nedlands WA 6009, Australia.
Riley
Thomas V
TV
Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150, *Division of Microbiology and Infectious Diseases, Western Australian Centre of Pathology and Medical Research, Nedlands WA 6009 and †Department of Microbiology, University of Western Australia, Nedlands WA 6009, Australia.
Robertson
Ian D
ID
Hampson
David J
DJ
D016470:Bacteremia / Q000175:diagnosis / Q000382:microbiology*; D017400:Brachyspira / Q000254:growth & development / Q000302:isolation & purification; D003470:Culture Media; D006801:Humans; D013143:Spirochaetaceae / Q000254:growth & development / Q000302:isolation & purification*; D013145:Spirochaetales Infections / Q000175:diagnosis / Q000382:microbiology*
D003470:Culture Media