Video - Zellweger spectrum disorders (NORD)

Zellweger spectrum disorders, or ZSDs, are rare autosomal recessive disorders caused by mutations in the PEX genes. Symptoms and disease progression vary greatly where severe forms are evident at birth, and mild and intermediate forms may go undetected until childhood. Symptoms often include cranial abnormalities, visual and hearing impairments, developmental delays, hypotonia, seizures, and bleeding problems.

ZSD affects the functioning of peroxisomes, causing buildup of very long-chain fatty acids and degeneration of nerves, affecting multiple organ systems. Diagnosis involves a thorough clinical examination, as well as biochemical and genetic testing. Effective treatment for ZSD requires early diagnosis and involves oral bile acid replacement therapy with cholic acid.