A Case of Arteriovenous Fistula after Renal Biopsy in an IgA Nephropathy Patient with Macroscopic Hematuria
A 27-year-old woman had a renal biopsy because of intermittent macroscopic hematuria and proteinuria after tonsillitis. When she was 24 years old, the first episode of macroscopic hematuria and proteinuria (1.0 g/g Cr) occurred just 1 day after tonsillitis with a high fever. After treatment with antibiotics, all symptoms disappeared except for microscopic hematuria. Because such episodes recurred several times and there was continued microscopic hematuria without proteinuria, the patient underwent tonsillectomy when she was 26 years old. However, even after tonsillectomy, microscopic hematuria persisted, and she repeatedly had episodes of macroscopic hematuria and proteinuria following pharyngitis with a high fever. She had a renal biopsy under real-time ultrasonographic guidance with a 16-gauge automated biopsy device and was diagnosed with IgA nephropathy. The histology showed crescent formations in 2 out of 16 glomeruli, but she refused steroid therapy. Before being discharged from our hospital, evidence of only slight renal subcapsular bleeding in the left kidney could be found on routine ultrasonography. Three months after the renal biopsy, she had sudden macroscopic hematuria without any symptoms, which lasted for 3 days. After that, the macroscopic hematuria disappeared but the amount of microscopic hematuria was clearly increased as compared to before her renal biopsy. In the urinary sediment, red blood casts were always present and comprised of 20–40% dysmorphic red blood cells. Since an enlarged left renal pelvis was newly recognized on ultrasonography, enhanced computed tomography (CT) was performed and she was diagnosed with an arteriovenous fistula (AVF) in the lower pole of her left kidney (fig. ). As the amount of microscopic hematuria had decreased again, she chose not to receive therapy. When she was 34 years old, our patient got married and was concerned about her future fertility. Since repeated ultrasonography showed an increased dilatation of the left renal vein (fig. ), she decided to undergo treatment with percutaneous intervention. An arteriogram confirmed an AVF with an enlarged draining vein and aneurysmal dilatation (fig. ). Selective embolization of the feeding arterial branch closed the AVF with 8 detachable coils (fig. ). Follow-up magnetic resonance imaging (MRI) performed 3 months after the intervention did not show any abnormalities, including the dilatation of the renal vein (fig. ). Microscopic hematuria disappeared within another 3 months and complete remission of IgA nephropathy had been achieved.