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.