Renal artery microaneurysms in ANCA associated vasculitis

A 60-year-old gentleman presented with decreased urine output and hemoptysis for the past 10 days. Physical examination revealed hypertension (BP-160/90 mm Hg), tachypnea, pallor and bilateral basal crepitations on chest auscultation. Laboratory investigations indicated severe anemia (Hb-7 g/dl) with a reduction in hemoglobin (by 2 g/dl in 24 h), as well as deranged renal function (urea = 185 mg/dl, creatinine = 8.57 mg/dl) and urinalysis showed a few RBC’s and trace albumin. High-resolution computed tomography (CT) of the chest showed bilateral ground-glass opacities with peripheral sparing suggestive of diffuse alveolar hemorrhage. The patient’s test for ANA, anti-GBM, anti-MPO antibodies were negative, but anti-PR3 was positive (71.7 IU/ml). The patient was diagnosed with ANCA-associated vasculitis (AAV) and treated with high doses of intravenous methylprednisolone (1 g × 3) along with plasma exchange. A renal biopsy from the left kidney revealed features suggestive of pauci-immune necrotizing crescentic glomerulonephritis. However, 5 h following renal biopsy, the patient experienced severe left loin pain accompanied by shock (70/40 mm Hg), a drop-in hemoglobin from 11 to 5.6 g/dl and deterioration of sensorium necessitated intubation and mechanical ventilation. CT angiography followed by digital subtraction angiography of the abdominal vessels showed multiple microaneurysms in the branches of the celiac, superior mesenteric and renal arteries (Figure 1A). A blush of contrast was seen at the inferior pole of the left kidney (Figure 1B), and coil embolization was performed. Unfortunately, the patient’s condition continued to deteriorate, and he sustained a cardiac arrest and died.