Granulomatosis with polyangiitis - the incomplete puzzle.

Granulomatous with polyangiitis (GPA) is a necrotizing granulomatous vasculitis that mostly affects small-sized vessels. The disease can affect many organs, although renal and respiratory tract involvement are the most frequent and distinguishing features. Musculoskeletal manifestations have been reported in about 50% of patients and can occur as myalgia, oligoarthralgia/arthritis of large joints or polyarthralgia/arthritis of small joints. Infrequently musculoskeletal symptoms can be the first disease manifestation, and in this clinical scenario GPA diagnosis might be delayed or mistaken by other rheumatic diseases. The authors describe three patients with musculoskeletal symptoms as earliest GPA manifestations, illustrating the clinical challenge.