PCR detection of Brachyspira aalborgi and Brachyspira pilosicoli in human faeces

previously-developed PCR protocols specific for the 16S rRNA gene of the in testinal spirochaetes Brachyspira aalborgi and Brachyspira pilosicoli were adapted for the detection of these species in human faeces, following DNA e xtraction and purification using mini-prep columns. The limits of detection in seeded farces for B. aalborgi and B. pilosicoli respectively were 2 x 1 0(2) and 7 x 10(3) cells per PCR reaction, equivalent to 5 X 10(4) and 1 x 10(5) cells per g of faeces. The PCR techniques were applied to faecal samp les from two patients with histological evidence of intestinal spirochaetos is. In the first patient, in whom B. aalborgi had been identified by 16S rD NA PCR from colonic biopsies. a positive amplification for B. aalborgi only was obtained from the faeces. The organism could not be isolated from thes e faeces. In the second patient, both colonic biopsies and Faeces were PCR positive for B. pilosicoli only, and B, pilosicoli was isolated from the fa eces. These new faecal PCR protocols should be valuable for future studies on the epidemiology of intestinal spirochaete infections in human populatio ns, particularly as it is not currently possible to isolate B. aalborgi fro m faeces. (C) 2001 Federation of European Microbiological Societies. Publis hed by Elsevier Science B.V. All rights reserved.