Diagnostic accuracy and the first genotype-phenotype correlation in glycogen storage disease type V.

Background: Glycogen storage disease type V (GSDV) is an autosomal recessive metabolic condition caused by pathogenic PYGM variants. This is an underdiagnosed condition as it presents with exercise intolerance in children. We reviewed the GSDV cases of a tertiary hospital center to assess diagnostic timing/accuracy, as well as potential clinical/analytical predictors of such factors.

Clinical and Laboratory Findings on Glycogen Storage Disease Type V: Results from a Retrospective Observational Study in a Tertiary Hospital.

Introduction - Glycogen storage disease type V (GSDV, MIM #232600) is an autosomal recessive metabolic myopathy caused by pathogenic variants in the PYGM gene. The characteristic symptoms of exercise intolerance, myalgia, and cramps, which improve after a few minutes of rest, are frequently unrecognized in affected children. When there is clinical suspicion, the initial approach with a forearm exercise test has diagnostic value by detecting low post-exercise plasma lactate-to-ammonia ratio values.

From recurrent rhabdomyolysis in a young adult to carnitine palmitoyltransferase II deficiency.

Metabolic myopathies are a diverse group of rare genetic disorders associated with recurrent episodes of rhabdomyolysis, induced by triggers such as fever or exercise. In these disorders, the energetic metabolism is compromised resulting in damage of the muscle cells. The diagnosis can be challenging but is essential for the correct treatment.