Novel compound heterozygous mutations in a GNE myopathy with congenital thrombocytopenia: A case report and literature review.

Abstract

We reported a GNE myopathy with congenital thrombocytopenia on a young male patient. He presented with a 3‐year history of lower distal extremity weakness initially affecting his legs. The weakness slowly progressed to lower proximal legs and upper arms last 6 months. Whole‐exome sequencing revealed that the patient harbored two heterozygous gene mutations, including a novel insertion mutation c.*1037_*1038CACACACACACACACACACACA and c.C478T in exome 12 and 3 of the GNE gene (NM_001128227), respectively. The levels of serum sialic acid in this patient were considerably decreased. Muscle MRI imaging showed the anterior and medial parts of his quadriceps were heavily affected by this disease. Hematoxylin and eosin staining showed prominent rimmed vacuoles with a lack of inflammatory response in the atrophied muscle. We also undertook a review of the current literature, searching for reports in which the GNE gene mutation caused the thrombocytopenia with or without muscle weakness. This new gene mutation finding broadens the GNE disease genotype spectrum, and further investigation of the relationship between GNE gene mutations and the heterogeneity of its clinical manifestations is needed.