[The clinical characteristics of 26 cases of amyopathic dermatomyositis].

OBJECTIVE

To analyze the clinical characteristics of amyopathic dermatomyositis (ADM).

METHODS

Twenty six patients diagnosed as ADM from January 2006 to January 2010 in PLA General Hospital were retrospectively analyzed. The clinical manifestation, laboratory findings, imaging manifestations, treatment and prognosis of the 26 patients were recorded.

RESULTS

There were 18 females and 8 males with age of 30-68 years. Overall disease course after diagnosis was 2-18 months. All patients had Gottron rash and interstitial pneumonia. Fifteen patients had history of pulmonary infections. Three patients had comorbidity of tumor. Creatine phosphokinase, creatine phosphokinase isoenzyme, glutamic-oxaloacetic transaminase and lactate dehydrogenase were normal in all 26 patients. Four patients had positive anti-Jo-1 antibodies. Antinuclear antibodies were positive in nine patients. Electromyogram was slightly abnormal in 5 patients. Muscle biopsy was abnormal in 19 patients. Twenty patients had improved after receiving corticosteroids and immunosuppressive agents. Six patients died.

CONCLUSIONS

It has been estimated that ADM represents approximately 20% of all cases of dermatomyositis. It seems that patients with ADM have greater incidence of lung involvement and combined cancer. ADM patients need to be treated positively to improve the prognosis.