ABSENCE OF ESCHERICHIA-COLI, LISTERIA-MONOCYTOGENES, AND KLEBSIELLA-PNEUMONIAE ANTIGENS WITHIN INFLAMMATORY BOWEL-DISEASE TISSUES

Background-Escherichia coli, Listeria, and streptococcal antigens have been found in Crohn's disease tissues. Antibodies to Klebsiella pneum oniae have been found in patients with inflammatory bowel disease and ankylosing spondylitis. The presence of these bacterial antigens in Cr ohn's granulomas would be of aetiological interest, while their presen ce in ulcers alone would be more likely to indicate secondary infectio n. Aim-To investigate inflammatory bowel disease tissues for the prese nce of these bacteria. Methods-Formalin fixed, paraffin processed sect ions from 53 patients (19 ulcerative colitis, 23 Crohn's disease; II n ormal tissues from cancer resections) were studied by immunohistochemi stry. Control tissue consisted of normal human small bowel injected su bmucosally with either E coli, Listeria monocytogenes, Proteus mirabil is, or Klebsiella pneumoniae serotypes K2, 3, 17, 21, 26, 36, and 50, and colonic biopsies from a child with E coli 0114 infection. Tissues were stained by Gram-Twort, and with specific antibodies for E coli (D ako B357), L monocytogenes (Difco 2302-50), and K pneumoniae (Biogenes is 5580-5208) using an immunoperoxidase technique. Results-Positive st aining for E coli was observed on the luminal surface epithelium and i n ulcers in 35% of Crohn's disease patients, 26% of ulcerative colitis patients, and no normal controls. Superficial staining for L monocyto genes was observed in one case of ulcerative colitis only. Staining fo r K pneumoniae was observed in one case of ulcerative colitis and one of Crohn's disease. No granulomas, giant cells, or germinal centres st ained positively for any of the three bacterial antigens. Conclusions- These data do not support a primary role for E coli, L monocytogenes, and K pneumoniae in inflammatory bowel disease. The presence off coli antigens in ulcers suggests secondary infection in these lesions.