Acute kidney injury as the presenting manifestation of sarcoidosis: A case series and review of literature.

Acute kidney injury is rarely the presenting feature of sarcoidosis. We present a case series of patients whose diagnosis of sarcoidosis was only brought to light by the development of renal impairment. Concurrent hypercalcaemia was noted, prompting further investigation. The patients discussed experienced a significant and rapid improvement in both renal function and hypercalcaemia in response to therapy with prednisolone. This is out of keeping with previous reports of sarcoidosis-induced renal impairment. Our case series highlights the importance of testing for hypercalcaemia in the context of acute kidney injury. Sarcoidosis is primarily a disease of the lungs and reticuloendothelial system; however, the prevalence of renal involvement with sarcoidosis may be under-recognized. The renal manifestations of sarcoidosis are discussed in the context of the current literature. Furthermore, from our experience, we postulate that in the context of sarcoidosis-induced renal injury, concurrent hypercalcaemia may present prior to the development of chronic renal injury and therefore these patients may be more likely to recover renal function.