From Dermatology to Nephrology: Unveiling Granulomatosis With Polyangiitis.

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is a rare form of pauci-immune vasculitis that primarily affects the respiratory tract and kidneys, though it can involve virtually any organ system. As a systemic vasculitis, it targets small- and medium-sized blood vessels and is associated with anti-neutrophil cytoplasmic antibodies (ANCA), particularly those directed against proteinase 3 (PR3). Due to its nonspecific symptoms and variable clinical presentation, GPA requires a high index of suspicion for timely diagnosis. Early treatment is essential, as the disease carries a high risk of morbidity and mortality if left untreated. We present a case of a patient with a one-year history of cutaneous lesions who was ultimately diagnosed with GPA, with an unusual concurrent infection by cytomegalovirus (CMV).