Juvenile dermatomyositis in Thai children

Area of Science:

• Pediatrics
• Rheumatology
• Dermatology

Background:

• Juvenile dermatomyositis (JDM) is a rare, chronic, multisystemic inflammatory disorder of unknown cause.
• It is characterized by a distinct skin rash and proximal muscle weakness in children.

Purpose of the Study:

• To retrospectively analyze cases of juvenile dermatomyositis diagnosed at a specific institute.
• To understand the clinical presentation, diagnostic findings, treatment outcomes, and long-term complications.

Main Methods:

• Retrospective review of medical records of patients diagnosed with JDM between 1988 and 1998.
• Analysis of presenting symptoms, cutaneous manifestations, diagnostic tests (EMG, muscle biopsy), and treatment responses.
• Evaluation of long-term outcomes, including calcinosis cutis.

Main Results:

• Seven cases of JDM were identified, with a female predominance (6:1) and a mean age of diagnosis of 7 years.
• Common symptoms included proximal muscle weakness and characteristic skin rashes like heliotrope signs and Gottron's papules.
• Electromyography and muscle biopsy confirmed myositis; oral prednisolone improved muscle weakness in most cases, with no mortality observed.
• Four patients developed calcinosis cutis, a complication that appeared 1-3 years after muscle weakness onset and was unresponsive to treatment.

Conclusions:

• Juvenile dermatomyositis can lead to chronic disability in children.
• Early diagnosis and prompt treatment are essential for preventing significant morbidity and mortality.
• Calcinosis cutis is a common, treatment-resistant complication that often manifests years after the initial presentation of muscle weakness.