MYH9 nephropathy

MYH9-related disorder is an autosomal dominant disease caused by a mutation in the MYH9 gene, which encodes nonmuscle myosin heavy chain IIA (NMMHC-IIA). This disease is characterized by giant platelets, thrombocytopenia, granulocyte inclusion bodies, proteinuria, and high-pitch sensorineural deafness. Nephropathy has been observed in 30% of patients with MYH9-related disorder. The characteristic features are early onset proteinuria and rapidly progressing renal disorder. However, the prognosis of MYH9 nephropathy remains unclear. Herein, we describe a 36-year-old woman who presented with proteinuria and was diagnosed with MYH9 nephropathy via renal biopsy and gene analysis. Her proteinuria improved after administration of an angiotensin II receptor blocker, but was aggravated after changing to a calcium channel blocker.