Familial sarcoidosis in Finland and Hokkaido, Japan - a comparative study

Two dr more cases of sarcoidosis in one family is not unusual. To compare t he frequencies of familial sarcoidosis in Finland and Hokkaido, Japan, and to analyse the type of associations reported, we collected data on all pati ents visiting hospitals for sarcoidosis in 1984 in Finland (1378 patients) and Hokkaido (208 patients), including information about familial sarcoidos is. We also analysed the familial cases seen among 571 sarcoidosis patients diagnosed at the Mjolbolsta hospital in Finland from 1955 to 1987 and amon g 686 Japanese patients seen in Sapporo from 1964 to 1988. In 1984, 50 sarcoidosis patients visiting Finnish hospitals and nine sarcoi dosis patients in Hokkaido reported as familial cases. Of the sarcoidosis p atients seen in Finland at the Mjolbolsta hospital in 1955-1987, 27 had a f amily member with the same disease, while this number was 20 in the Sapporo hospital in 1964-1988. Those surveys give a prevalence of familial sarcoidosis in Finland of 3.6-4 .7% and in Hokkaido of 2.9-4.3%. Among familial cases, the dominating relat ionships were sister-brother and mother-child relationships.