Abstract: PUB224
Renal Biopsy Performed to Diagnose Sarcoidosis but Diagnosed IgA Nephropathy: A Case Report
Session Information
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Shimizu, Yoshitaka, Seirei hamamatu general hospital, Hamamatu, Japan
- Misaki, Taro, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka, Japan
Introduction
Renal disorder attributed to sarcoidosis generally causes tubulointerstitial damage. We herein report a case in which renal biopsy was performed for sarcoidosis diagnosis but was diagnosed as IgA nephropathy.
Case Description
We encountered a 69-year-old female with persistent proteinuria and hematuria. Her history included facial palsy and neurosarcoidosis diagnosed by bronchoscopy (CD4/CD8 ratio: 7.22) and CT findings (hilar lymph node swelling) 5 years prior to visiting our hospital. She was treated with prednisolone (PSL) 50 mg and her symptoms improved. PSL was gradually tapered and discontinued. She had no proteinuria and no hematuria 2 years previously (Cr 0.68 mg/dL). She was diagnosed with renal disorder (Cr 0.92 mg/dL, proteinuria 1+, hematuria 3+) 1 year previously, and she subsequently visited our hospital. CT showed lung hilar region lymph node swelling and multiple mottled shadows in the liver. Laboratory findings included the following results: ACE 36.5 U/ml, 1,25(OH)2-vitamin D 67.4 pg/mL, soluble IL-2 receptor 2230 U/ml, proteinuria 0.46 g/day, and urine β-2 MG 9450 μg/L. We suspected recurrence of sarcoidosis and renal biopsy was performed for diagnosis. Mild to moderate increase of mesangial cells and matrix was observed in most glomeruli. Although tubulointerstitial injury was partially observed, epithelioid cell granuloma, which is characteristic of sarcoidosis, was not observed. IgA and C3 deposition in mesangial areas was observed in immunofluorescent analysis. Based on these findings, we diagnosed the patient with IgA nephropathy, not sarcoidosis, for the kidney lesion. Hepatic biopsy was then performed for definitive diagnosis, which showed epithelioid cell granulomas. The patient was finally diagnosed with sarcoidosis. She was subsequently treated with PSL 30 mg and her renal function and urinary findings improved.
Discussion
We experienced an interesting case that suggested IgA nephropathy diagnosed by renal biopsy and sarcoidosis diagnosed by liver biopsy. It is very rare for sarcoidosis to accompany IgA nephropathy. We speculate that IgA nephropathy occurred secondary to immune abnormality caused by sarcoidosis.