A Rare Case of Polyneuropathy and Monoclonalgammopathy with Recurrent Acute Kidney Injury.

POEMS syndrome is a rare paraneoplastic syndrome and there are few reports of polyneuropathy and monoclonal gammopathy associated with kidney dysfunction. Here, we report a case of POEMS syndrome with recurrent acute kidney injury (AKI). A 52-year-old man presented with bilateral aggravating paresthesia and latermotor weakness of the lower extremities accompanied by repeated elevation of serum creatinine. The patient was finally diagnosed with POEMS syndrome on the basis of fulfilling the two mandatory major criteria (polyneuropathy and monoclonal gammopathy), one other major criterion (sclerotic bone lesion), and several minor criteria. A renal biopsy was performed to clarify the cause of AKI and showed membranoproliferative glomerulonephritis-like lesions with mesangiolysis and endothelial cell injury. This case illustrates that renal manifestations, not included in the diagnostic criteria for POEMS, can be apparent before various other systemic symptoms.