occipital horn syndrome
Occipital horn syndrome is a rare X-linked disorder of copper metabolism resulting in connective tissue abnormalities. Menkes disease is the severe form of this disease, with patients rarely surviving past 3 years of age. Occipital horn syndrome (also known as X-linked cutis laxa or Ehlers Danlos type IX) could be considered a forme fruste of this disease.
Epidemiology
The occipital horn syndrome has been reported in 200 families worldwide.
Pathology
Both conditions are caused by mutations of the ATP7A gene located on the X chromosome which results in the abnormal metabolism and distribution of copper. Copper-containing enzymes are required for the formation of proteins.
Menkes disease / kinky hair syndrome
Menkes kinky hair syndrome, the severe form of this disease is characterized by frizzy hair, failure to thrive, nervous system abnormalities, and death before the age of 3.
Occipital horn syndrome
- bilateral occipital exostoses, hence the name
- tortuous vessels
- long thin face, high forehead
- short clavicles
- pectus excavatum / pectus carinatum
- inguinal herniation
- chronic diarrhea
- bladder diverticulum
- developmental delay
- intellectual disability of varying severity