Humoral Immune Response and Luminal Microorganisms in Patients with Indeterminate Colitis


Abstract:Background: Microorganisms that directly interact with the intestinal mucosa are obscured by fecal flora. Some members of the endogenous faecal microflora have a clear detrimental role in most animal models of colitis and enteritis. This is strongly suspected to be the cause of indeterminate colitis.Objective: Determination of humoral immune response and luminal microorganisms in patients with indeterminate colitis.Patients & Methods: The study consisted of two groups: 75 patients groups with indeterminate colitis and control group consisted of 30 healthy volunteers. Sigmoidoscope and colonoscope examination were done for the patients group and biopsy were also taken from ulcer lesion for histopathological examination for confirming the diagnosis. Blood samples were collected from them and serum were collected for immunoglobulins (IgG, IgM and IgA) levels and complement (C3 and C4) level by single radial immune diffusion method (Biomaghrib-Tunis). Fecal and rectal swabs were taken from those groups, cultured on different bacteriological media. Results: Males more than females are affected. The majority of them were complaining from rectal bleeding. Most of their diseased location was in rectum then sigmoid and ascending colon. Bacteriological results showed a significant decrease in the existence of Bacteroids fragilis (anaerobic bacteria) in patients group compared with control. Studying humoral immune response demonstrated a significant higher level in IgG, IgA, C3 and C4 in patients group and significant decrease in IgM level.Conclusions: Reduction in anaerobic bacteria might be a cause in initiation colitis with stimulation of immunoglobulins production and complement activation to overcome this inflammation.Key wards: colitis, Immunoglobulins, anaerobic bacteria.