To investigate the association between the human leukocyte antigen (HLA) system and adhesions causing intestinal obstruction in childhood in order to determine whether HLA profiles can be used to identify and screen individuals at risk for intestinal adhesions, clinical and laboratory evaluations were done in a total of 42 (F:M = 27:15) patients. The mean age was 6.11 +/- 3.2 years (0.6-13 years). The patients were: tested for HLA phenotype in two groups; the KLA phenotype distribution and relative risk (RR) for adhesions were determined. The study patients were children operated upon due to acute abdominal emergencies. Group 1 included patients who needed readmission after the surgery due to intestinal obstruction (n = 19), group 2 patients had no readmission for any reason following surgery (n = 23). Of the 19 patients in group 1, 9 were treated only medically and 10 needed surgical intervention. Among the patients in whom medical treatment was initiated (n = 14), 5 needed surgery during followup. There was an increased RR for certain HLA subtypes (A24 , HLA11, DR11 , B22) in patients presenting with intestinal obstruction due to adhesions. among these, A24 (9) and DR11 (5) were statistically significant (P < 0.05) compared with the control group. Several possible mechanisms could link the HLA system with disease, especially those in which the immune response is suspected to be involved, but the questions of how the inflammatory response is initiated and the role of proinflammatory cytokines remain unclear. Future research developments are likely to focus on increased understanding of the molecular biology of the major histocompatibility complex and its biological function in the immune response and adhesion formation and intestinal obstruction. It is possible that HLA profiles can be used to identify individuals at risk for intestinal adhesions in the future.