General description

Chromosome 18q deletion syndrome is a genetic disorder caused by deletion in the long arm of chromosome 18, where haploinsufficiency of multiple genes leads to various clinical symptoms. The condition is characterized by growth delays (particularly short stature) and distinctive facial features including midline hypoplasia, inverted lower lip, thin upper lip, deep-set eyes, and potential cleft lip/palate.

Physical manifestations include congenital heart defects in more than a quarter of patients, vertebral abnormalities such as scoliosis and kyphosis, and urological issues in males including hypospadias and potential vesicoureteral reflux with urinary tract infections. Patients also experience sensory issues including sensorineural or mixed hearing loss and various ophthalmological abnormalities like nystagmus and ocular movement disorders. Thyroid dysfunction may occur as well.

Developmental aspects of the syndrome include generalized developmental delays, typically severe intellectual disability, and autism spectrum features. Other behavioral issues can include hyperactivity, anxiety, irritability, mood disorders, and depression. Despite these multiple challenges, the overall life expectancy is generally good for those with this syndrome.