IMPAIRED GUT BARRIER FUNCTION IN MALNOURISHED PATIENTS

The gastrointestinal tract is essential to host defence, acting as a b arrier to absorption and translocation of gut antigens, including bact eria. In experimental models, protein malnutrition is permissive to gu t barrier failure and endogenous infection. A clinical correlate has n ot been described. Intestinal morphology and barrier function to food protein antigens was studied in malnourished patients. Thirty-five ind ividuals were evaluated, 20 malnourished patients and 15 well nourishe d hospital controls. Morphology was assessed from endoscopic biopsies of the second part of the duodenum, and serum immunoglobulin (Ig) G an tibodies to gliadin and beta-lactoglobulin were measured. No antibody to food proteins was evident in the control group. In contrast, serum IgG antibodies to at least one antigen were present in 15 malnourished patients and to both antigens in ten (P<0.0001 versus controls). Seve rely malnourished patients were more likely to have both antibodies pr esent than those with mild or moderate malnutrition (P<0.05). Antibody -positive malnourished patients had significantly better nutritional s tatus than antibody-negative patients with malnutrition (P<0.05). In n o group of patients was there morphological evidence of abnormal mucos a or an immunological infiltrate. Gut barrier function is compromised in malnourished patients which suggests a mechanism that may facilitat e gut-derived infection and sepsis.