Clinical, Biochemical, and Histological Manifestations and Long-Term Outcomes of Renal Sarcoidosis - A Single Center Study.

Background: Renal involvement in sarcoidosis is rare. We evaluated the pattern of renal involvement in sarcoidosis, its clinical course, renal histology, and response to treatment.
Materials and Methods: We retrospectively analyzed the data of all cases with sarcoidosis exhibiting renal involvement referred to our department between January 2010 and December 2021.
Results: A total of 33 patients (age: 50.6 ± 12.6 years, males: 57.6%) were analyzed. Common presenting symptoms were weight loss (81.8%; n = 27), fever (75.8%; n = 25), and vomiting (63.6%; n = 21). A total of 14 (42.4%) patients had granulomatous interstitial nephritis (GIN), 13 (39.4%) had isolated hypercalcemia, and six (18.2%) had GIN along with hypercalcemia. Renal biopsy was performed in 20 (60.6%) patients, and all showed GIN, with concomitant glomerular disease in four (12.1%) patients. Mean serum creatinine and 24-h urine protein at presentation were 4.3 ± 2.1 mg/dL and 2.5 ± 0.9 g/day, respectively. All patients received oral prednisolone 1 mg/kg/day with subsequent tapering, concomitantly with azathioprine. Mycophenolate mofetil was used in three (9.1%) patients who developed azathioprine-induced hepatoxicity. After a median follow-up of 24 months (8-120 months), mean serum creatinine and 24-h urine protein improved to 1.9 ± 1.5 mg/dL and 1.1 ± 0.6 g/day, respectively, ( P = 0.005). On follow-up, two patients (6.1%) became dialysis-dependent, and three (9.1%) succumbed: one due to a cardiovascular event and two to sepsis and septic shock.
Conclusion: Granulomatous interstitial nephritis was the most common diagnosis in sarcoidosis patients with kidney failure. Early steroid treatment improves kidney function.
Competing Interests: There are no conflicts of interest.
(© 2024 Indian Journal of Nephrology | Published by Scientific Scholar.)