A Mild Clinical Phenotype with Myopathic and Hemolytic Forms of Phosphoglycerate Kinase Deficiency (PGK Osaka): A Case Report and Literature Review.

Phosphoglycerate kinase (PGK) deficiency is an X-linked disorder characterized by a combination of hemolytic anemia, myopathy, and brain involvement. We herein report a Japanese man who had several episodes of rhabdomyolysis but was training strenuously to be a professional boxer. Mild hemolytic anemia was noted. The enzymatic activity of PGK was significantly reduced, and a novel missense mutation, p.S62N, was identified in the PGK1 gene. A literature review revealed only one case with a mixed hemolytic and myopathic phenotype like ours. This mild phenotype indicates the complex pathophysiology of PGK deficiency and suggests the benefits of dietary control and exercise.

[A case of dysferlinopathy asymptomatic for 10 years after an episode of transient muscle weakness].

We report a 28-year-old male with dysferlinopathy, who has remained asymptomatic for 10 years from a rhabdomyolysis-like episode. He had been in good health since birth, but felt difficulty in walking after a month and a half of manual labor at 18 years old (at the year 2000). Rhabdomyolysis was suspected because of muscle weakness and elevated serum CK of 28,094U/L. He was hospitalized and his muscle weakness improved. He was referred to us, because his serum CK remained around 2,000U/L. Histological analysis of muscle, when anti-dysferlin antibody was unavailable, was not informative but later analysis at the age of 23 using preserved specimen showed loss of dysferlin immunoreactivity. Subsequently, a missense mutation (c.2997G>T) and a deletion (c.3373delG) of the dysferlin gene, both of which are common in Miyoshi myopathy in Japanese, were identified. He continuously showed hyper-CKemia, but no apparent muscle weakness emerged for more than ten years. Reports on asymptomatic dysferlinopathy over such a long duration are rare. This case may suggest that genetic factors, environmental factors such as intensity of work-load, or both, might affect the clinical course of dysferlinopathy. Further follow-up is necessary.