Muskuläre Polyarteriitis nodosa – eine fallbasierte Übersichtsarbeit

BACKGROUND: Myalgia is a common but unspecific set of symptoms that may be caused by orthopedic, neurological and internal medical conditions, often resulting in a diagnostic challenge. Muscular polyarteritis nodosa (PAN) is a rare differential diagnosis of myalgia with elevated serological inflammatory markers.

OBJECTIVE: Based on three clinical cases and the literature this review describes the essential clinical and diagnostic features of muscular PAN.

RESULTS: Muscular PAN typically presents with immobilizing myalgia confined to the lower limbs and elevated serological inflammatory markers but often normal creatine kinase (CK) levels. Contrast-enhanced magnetic resonance imaging of the affected muscles, which can often mimic myositis, and muscle biopsy provide the relevant histological findings that lead to the diagnosis of a vasculitis.

CONCLUSION: With respect to own experiences and the reviewed literature, muscular PAN should be considered as a possible diagnosis in cases of myalgia with elevated inflammatory markers but normal CK levels and a lack of further symptoms typical for vasculitis.