FAMILIAL CROHNS-DISEASE - A STUDY OF 18 FAMILIES

The high frequency of familial Crohn's disease (CD) suggests a genetic predisposition. The most recent data from epidemiology and molecular biology are consistent with a multifactorial, polygenic inheritance wi th a possible genetic heterogeneity. The aim of our study was, first t o compare familial and sporadic CD on the basis of the type and locati on of the disease, and age at diagnosis, and second, to evaluate among families, the concordance rate for the type and location of the disea se. Patients and methods: Is families with 2 (n = 16) and 3 bn = 2) af fected first degree relatives were studied. They were compared to a po pulation of 154 sporadic CD coming from the same gastroenterology unit . Results: Age at diagnosis was the same in sporadic and familial CD. There was an increased frequency of ileal (p = 0.02), and fibro stenot ic (p=0.005) CD and a decreased frequency of colonic (p = 0.006) and i nflammatory (p = 0.02) disease, in familial CD. There was a significan t increase in concordance rate for fibro-stenotic disease (p < 0.001) and a decrease for inflammatory disease (p < 0.01), among the families . The observed concordance rate for the location of the disease was no t significantly different from the expected one. In conclusion, these data suggest that CD may be heterogenous and that different clinical p atterns mag be determined either by genetic or environmental factors.