Biochemistry

Uh oh, it's the glycogen metabolism pathway.

The classic infantile form of this disease presents in the first few months of life with cardiomyopathy and severe generalized muscular hypotonia. At the median presentation age of four months, infants will have cardiomegaly, respiratory distress, muscle weakness, feeding disorders, and failure to thrive. Standard metabolic labs will be normal, but serum creatine kinase will be elevated.

A late onset juvenile or adult form presents without cardiac problems. The age of presentation varies, but the presentation is primarily skeletal myopathy eventually leading to respiratory failure. Children might present with delayed gross motor development, and adults might present with progressive limb girdle weakness (starting with hip flexors). Creatine kinase will be elevated as well.

Challenge: What autosomal recessive disease is this?

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