Nail dystrophy affects both toes and fingers; it
can be present at birth or developed during early childhood. Palmoplantar
keratoderma becomes apparent in later childhood. Clinical (abnormal gait,
hypertonia, spasticity, rigidity, paraparesis, quadriparesis) or
electrophysiological evidence of axonal neuropathy with muscular atrophia
are observed. Muscle histological lesions can be present. Respiratory
insufficiency can occur.