A Rare Case of Granulomatosis With Polyangiitis Presenting as Retroperitoneal Fibrosis in the Peri-Iliac Region Causing Hydronephrosis

Abstract

Wegener’s granulomatosis, now more commonly referred to as granulomatosis with polyangiitis (GPA), is a rare, idiopathic, systemic inflammatory disease, most commonly involving the respiratory tract, kidneys, and sinonasal region. The condition affects small and medium-sized blood vessels, such as arteries, arterioles, venules, and capillaries. Some cases of the disease presenting as retroperitoneal fibrosis and/or affecting the aorta have been reported. Although advances in the treatment of GPA have contributed to a decline in mortality, early diagnosis is still of vital importance due to the possible complications of the disease. Here, we present the case of a 69-year-old man with acute-onset abdominal pain. Ultrasound of the abdomen showed left-sided hydronephrosis. Computed tomography detected cavitating pulmonary lesions and peri-iliac alterations caused by retroperitoneal fibrosis with involvement of the crossing ureter. Laboratory results revealed high antineutrophil cytoplasmic antibody levels and high inflammatory markers. A lung biopsy performed via bronchoscopy revealed necrotizing granulomas and solidified the diagnosis of GPA both in the lung and the peri-iliac region. Treatment with immunosuppressive agents and glucocorticoids was initiated. A follow-up after two months showed regression of the pulmonary lesions and partial resolution of the hydronephrosis as well as reduced inflammatory markers in the blood tests.

Urological Manifestations of the Systemic Vasculitides—A Scoping Review

“…Ureteral stenosis due to retroperitoneal inflammation or segmental thickening of surrounding vessels can also be associated with GPA [43]. However, it is a rare manifestation as only 11 cases have been reported in the literature to date [44].…”