Mycobacterium paratuberculosis DNA not detected in Crohn's disease tissue by fluorescent polymerase chain reaction.
The role of mycobacteria in the aetiology of Crohn's disease has been a contentious subject for many years. Mycobacterium paratuberculosis is known to cause a chronic granulomatous enteritis in animals (Johne's disease) and has been implicated as a possible infectious cause of Crohn's disease. However this fastidious organism is only rarely detected by conventional microbiological techniques. This study used oligonucleotide primers to the species-specific M paratuberculosis IS900 DNA insertion element and the polymerase chain reaction to amplify any M paratuberculosis DNA from intestinal tissue DNA extracts. One oligonucleotide primer was fluorochrome-labelled and the presence of fluorescent amplified product was determined using an automated DNA sequencer with a computerised gel-scanning laser. This method was shown capable of detecting 1-2 mycobacterial genomes. Intestinal tissue samples were obtained from 68 patients with histologically confirmed Crohn's disease, 49 patients with histologically confirmed ulcerative colitis, and 26 non-inflammatory bowel disease controls. In no case was M paratuberculosis detected in any of the inflammatory bowel disease tissue samples and only one non-inflammatory bowel disease case was positive. These results do not support the hypothesis that M paratuberculosis has an aetiological role in Crohn's disease.
Division of Medicine, St James's University Hospital, Leeds.
D S
DS
Rowbotham
N P
NP
Mapstone
L K
LK
Trejdosiewicz
P D
PD
Howdle
P
P
Quirke
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D003093:Colitis, Ulcerative / Q000382:microbiology; D003106:Colon / Q000382:microbiology; D003424:Crohn Disease / Q000382:microbiology*; D017931:DNA Primers / Q000737:chemistry; D004269:DNA, Bacterial / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D007421:Intestine, Small / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016927:Mycobacterium avium subsp. paratuberculosis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity
D017931:DNA Primers; D004269:DNA, Bacterial