[Juvenile dermatomyositis--statistical observation of 105 patients with dermatomyositis]

Statistical observation about the clinical items of 105 patients with dermatomyositis (DMS) attending Department of Dermatology, Nagoya University Hospital and some hospitals in Aichi Prefecture, during the year of 1965 to 1989, was carried out. Clinical features of the patients with juvenile DMS obtained from the observation were as follows. 1) The male:female ratio was 1.3:1 in juvenile DMS. The evident difference such as the predominance of females in adult DMS was not found. 2) The tendency that cutaneous manifestations usually preceded muscular manifestations was observed, and the muscular manifestations except severe symptoms were seen with a high incidence throughout the entire clinical course. 3) In the laboratory examinations, the incidence of elevation of serum aldolase concentrations in children was significantly higher than that in adults (p less than 0.05). Serum aldolase concentrations were usually elevated at onset or prior to the onset of muscular manifestations. Therefore the measurement of serum aldolase levels was considered to be useful for early diagnosis of juvenile DMS. The positive rate of antinuclear antibody in children was significantly lower than that in adults (p less than 0.001). 4) None of the children had any complications such as malignant tumors, interstitial pneumonia and pulmonary fibrosis, and none of them died. With regard to the outcome, the incidence of "remission or improvement" in children was significantly higher than that in adults (p less than 0.05). In the group of "same or worse", the children mainly had the cutaneous manifestations which were difficult to treat, compared with the adults. These results suggest that juvenile DMS may be a different disorder, probably a syndrome, from adult DMS.