A Homozygotic Mutation in KDSR may Cause Keratinization Disorders and Thrombocytopenia: A Case Report

Pathogenic mutations in 3-keto-dihydrosphingosine reductase (KDSR) gene are associated with keratinization disorders and impaired platelet function. However, no case with both homozygotic mutation of KDSR and hepatic hemangioendothelioma has ever been reported due to its low prevalence. Here we report a seven months old Chinese boy with a homozygotic missense mutation in KDSR and both of his parents carry a same heterozygous mutation. He was born with thick plate-like scales overlying erythrodermic skin, but the skin symptoms were resolved spontaneously over the first month of his birth. He was also diagnosed with hepatic hemangioendothelioma at birth and accepted a resection surgery at 2 months old. At birth, his platelet count was severely low (10-20×10⁹/L) with recurrent skin and gingival bleeding. Meanwhile, he suffered a mild normocytic, normochromic anemia with normal iron and hematinic levels. The anemia spontaneously recovered over the first 6 months, while the platelet count keeped at a low level (4-20×10⁹/L). Treatment with corticosteroids, immunoglobulin or thrombopoietin was all suboptimal.