[Juvenile dermatomyositis: A series of 22 cases]

To report on the characteristics of juvenile dermatomyositis (JDM).

This was a retrospective, descriptive, cross-sectional, non-interventional, multicenter study conducted in Alsace between 2000 and 2015. The patients, aged 0 to 16years, had JDM according to both the Bohan and Peter and the EULAR/ACR criteria.

A total of 17 girls and 5 boys were included with a median age at disease onset of 7,8years (Q1-Q3: 4.4-12.9). Median duration of JDM and median patient follow-up were 2.8years and 6.2years, respectively. The most common skin symptoms were papules or Gottron's sign (86 %), nail lesions (82 %), erythema of the face (77 %) and eyelids (59 %), photosensitivity (59 %), and calcinosis (27 %). One patient presented papules with a depressed and porcelain-white center ("Degos-like" lesions). One patient had algodystrophy. Two patients were clinically amyopathic. One girl had intestinal vasculitis. Respiratory function tests were abnormal in 27 % of cases. Median treatment duration was 42 months (Q1-Q3: 19-63). Three patients had a monocyclic form, 12 had a polycyclic form, and 7 had chronic disease.

The frequency of cutaneous and musculoskeletal signs is comparable to that of other large cohorts of JDM. "Degos-like" lesions and algodystrophy have not yet been described in JDM. This study highlights the type and extent of the dermatological manifestations that frequently constitute the presenting complaint in this disease.