Impaired gut barrier function in malnourished patients

Abstract

The gastrointestinal tract is essential to host defence, acting as a barrier to absorption and translocation of gut antigens, including bacteria. In experimental models, protein malnutrition is permissive to gut barrier failure and endogenous infection. A clinical correlate has not been described. Intestinal morphology and barrier function to food protein antigens was studied in malnourished patients. Thirty-five individuals were evaluated, 20 malnourished patients and 15 well nourished hospital controls. Morphology was assessed from endoscopic biopsies of the second part of the duodenum, and serum immunoglobulin (Ig) G antibodies 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). Severely malnourished patients were more likely to have both antibodies present than those with mild or moderate malnutrition (P < 0.05). Antibody-positive malnourished patients had significantly better nutritional status than antibody-negative patients with malnutrition (P < 0.05). In no group of patients was there morphological evidence of abnormal mucosa or an immunological infiltrate. Gut barrier function is compromised in malnourished patients which suggests a mechanism that may facilitate gut-derived infection and sepsis.

Increased intestinal permeability in malnourished patients with liver cirrhosis

“…10 Antibodies to food proteins have been shown in malnourished patients, which implies compromised gut barrier function. 11 Measurement of urinary excretion of orally administered, nonmetabolizable sugar probe molecules 12 is one established method to test gastrointestinal permeability. Sucrose is considered a marker for the gastroduodenal permeability during the first 5 h. 13 The lactulose/mannitol ratio (permeability index) is a marker for intestinal permeability corrected for differences in variable gastric emptying, intestinal transit time during the first 5 h and renal clearance.…”

Translocation of indigenous microflora in an experimental model of sepsis

“…Most studies investigating a possible relationship between histological changes in mucosae and translocation have focused on changes in the small bowel and only a few studies have analysed and demonstrated alterations in colonic mucosa [12,13]. Passage of bacteria through mucosal membranes and survival in extra-intestinal sites depend on the effectiveness of the host immune system.…”

Multi-Disciplinary Approach for Behavioural Disorders

“…A diet rich in carbohydrates, sugar and lactose causes havoc in this environment, maintaining the dysbacteriosis. This promotes the growth of other pathogens (Campylobacter/Klebsiella), that not only destroy the gut mucosa but also expose the body to their toxins resulting in low-grade toxaemia, as the gut fails to form a barrier [3,4] to luminal micro-organisms and endotoxins.…”