Granulomatosis with polyangiitis (Wegener's granulomatosis): a rare variant of sudden natural death.

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is the most common form of life-threatening small-vessel vasculitis. Although its exact pathogenesis remains unclear, GPA is believed to belong to the wide complex of autoimmune diseases due to the presence of anti-neutrophil cytoplasmatic antibodies with cytoplasmic staining pattern (c-ANCA) that is expressed in activated neutrophils. GPA predominantly manifests at the upper and lower respiratory tract and the kidneys, but the impairment of multiple organ systems is possible as well. The so-called classical clinical triad of GPA comprises sinusitis, pneumonia, and glomerulonephritis. Despite the fact that there is an elevated risk of mortality for patients suffering from GPA, sudden death due to GPA is a rare and difficult differential diagnosis of sudden natural death in forensic case work. In the present article, the rare case of a 41-year-old male, who died of a sudden death due to previously undiagnosed GPA, is demonstrated. The final diagnosis was feasible by close interdisciplinary collaboration, considering the entire body of findings obtained during autopsy, histopathological investigation, and analysis of the clinical records. Therefore, it remains necessary to point out that especially for rare causes of death, interdisciplinary collaboration is essential in order to concretize the cause of death and exclude rare differential diagnoses of sudden unexpected death of hospitalized patients in forensic case work.