Muscular polyarteritis nodosa: a diagnostic and therapeutic challenge

Area of Science:

• Rheumatology
• Neurology
• Vascular Medicine

Background:

• Muscular polyarteritis nodosa (m-PAN) is a rare systemic vasculitis affecting muscles.
• Diagnosis can be challenging due to non-specific symptoms like fever and myalgia.
• Early recognition is crucial for effective management and preventing complications.

Purpose of the Study:

• To report a rare case of m-PAN in a healthy young adult.
• To illustrate diagnostic challenges and the utility of advanced imaging and biopsy.
• To emphasize the importance of timely immunosuppressive treatment.

Main Methods:

• Clinical presentation of fever, severe myalgia, and inflammatory markers.
• Diagnostic workup including repeat MRI revealing myositis and muscle biopsy confirming necrotising vasculitis.
• Treatment initiated with corticosteroids, followed by cyclophosphamide and intravenous immunoglobulin.

Main Results:

• Initial corticosteroid therapy provided partial symptom relief.
• Combination therapy with cyclophosphamide and IVIg led to gradual resolution of symptoms.
• Successful management of a rare case of m-PAN.

Conclusions:

• m-PAN should be considered in patients presenting with localized myalgia and systemic inflammation.
• MRI is valuable for detecting myositis and guiding muscle biopsy.
• Prompt initiation of immunosuppressive therapy is essential for favorable outcomes in m-PAN.