Sarcoidosis: Incidental Finding in Acute Renal Failure, Hypercalcemia, and Elevated Angiotensin Converting Enzyme
Abstract
Sushil K. Mehandru, Supreet Kaur, Avais Masud, Prit Paul Singh, Kyrillos Rezkalla, Zaineb Abdulrahman, Tushar Vachharajani and Arif Asif
Acute renal failure is a rare presenting feature of sarcoidosis. We report two cases not known to have sarcoidosis, presenting with acute renal failure. Laboratory reports revealed elevated serum creatinine levels as well as hypercalcemia. Renal biopsy showed acute granulomatous interstitial nephritis, non-caseating granulomas, and interstitial fibrosis. Hypercalcemia and renal failure improved to normal levels within two weeks of initiation of steroid therapy. Extensive work up was negative for malignancy. Parathyroid hormone (iPTH) was suppressed, and parathyroid-related peptide (PTHrP) was negative, indicating non-parathyroid origin of hypercalcemia in both cases. Angiotensin converting enzyme(ACE) was elevated in both and returned to normal with steroid therapy. Serum ACE as well as ionized calcium levels may be considered as a biomarker of sarcoid associated hypercalcemia.