Panniculitis in a patient on methotrexate for mixed connective tissue disease

Area of Science:

• Rheumatology
• Dermatopathology

Background:

• Methotrexate is a common immunosuppressive drug used for various inflammatory conditions.
• Accelerated nodulosis is a recognized adverse effect of methotrexate, particularly in rheumatoid arthritis.
• Emerging reports suggest nodulosis can occur in other inflammatory diseases treated with methotrexate.

Observation:

• Panniculitis, an inflammation of subcutaneous fat, is a recently identified pathological entity in patients on methotrexate.
• This report details a case of panniculitis in a woman undergoing methotrexate treatment.
• The patient was being treated for mixed connective tissue disease.

Findings:

• The case presented demonstrates panniculitis as a potential manifestation of methotrexate therapy.
• This expands the spectrum of known methotrexate-associated nodular reactions.
• Panniculitis represents a distinct pathological finding in this context.

Implications:

• Clinicians should consider panniculitis in the differential diagnosis of skin lesions in patients on methotrexate.
• Further research is needed to understand the mechanism linking methotrexate to panniculitis.
• This finding may necessitate adjustments in patient monitoring and treatment strategies for inflammatory conditions.