[Dermatomyositis associated with normal serum muscle enzyme levels]

Area of Science:

• Rheumatology
• Neurology
• Immunology

Background:

• Polymyositis and dermatomyositis are inflammatory myopathies.
• Elevated serum muscle enzymes, particularly creatine kinase, are typical diagnostic markers.
• Normal enzyme levels throughout the disease course are exceptionally uncommon.

Observation:

• This report details a rare case of dermatomyositis presenting with normal serum muscle enzyme levels.
• Creatine kinase levels remained within the normal range during the entire clinical course.
• The patient was monitored for 18 months.

Findings:

• No evidence of malignancy was detected during the follow-up period.
• No signs of interstitial lung disease were observed.
• The patient's condition did not follow the previously suggested poor prognostic indicators associated with normal creatine kinase.

Implications:

• The absence of elevated creatine kinase in dermatomyositis may not invariably predict a poor prognosis.
• Further research is needed to understand the clinical significance of normal enzyme levels in specific dermatomyositis cases.
• This case challenges existing assumptions about diagnostic markers and prognosis in inflammatory myopathies.