X-Linked Myopathy With Excessive Autophagy

X-linked myopathy with excessive autophagy is a childhood-onset X-linked myopathy characterised by slow progression of muscle weakness and unique histopathological findings.

Epidemiology

It has been described in about fifteen families.

Clinical description

The first manifestations appear typically in children around 5-10 years of age and include difficulty climbing stairs and running.

Etiology

The Xq28 locus has been associated with the disease.

Diagnostic methods

Muscle fibres are not necrotic but they show excessive autophagic activity and exocytosis of the phagocytosed material.

Genetic counseling

Transmission is X-linked recessive; female carriers are asymptomatic or only mildly affected.

Prognosis

Progression is very slow, longevity is not altered. Many patients need a wheelchair in their 6th decade of life.