[Irregular behavior of complement in coeliac disease (author's transl)].

Ninety-six sera from coeliac children were studied, 55 were taken during a normal diet and 41 with a gluten-free diet. C'3, C'4, C'5, C'3, PA, C'1 INH and C'3b INA were measured. No significant differences were found between coeliac patients and normal controls. Results were also similar for gluten-free diet coeliac childrens and for active patients. A challenge was performed with 20 g. of gluten in 14 active patients. The levels of C'3, C'3 PA had a large variability, increasing and decreasing, but no similar and constant pattern was found. Activation products of C'3 appeared, specially between 4 and 24 hours, and disappeared about 48 hours. These results support an alteration of complement in coeliac patients but there is not a constant and steady pattern. Our hypothesis is that complement activation is not a pathogenic mechanism of coeliac disease. Maybe is just a consequence or epiphenomenon.