HIVEP2 disorder is associated with neurological, developmental, and other challenges.
Neurodevelopmental features
In early childhood, affected individuals may have delays in cognitive, language, and motor abilities. Language development may be slowed, and sometimes affected individuals may not have speech. Low tone and delayed motor development can occur. Walking may be unsteady.
Intellectual disability and autism spectrum disorder are common in this condition. Behavioural features include attention deficit hyperactivity disorder, anxiety, and aggression.
Affected individuals may have a small head size. MRI of the brain may show altered development of a structure of the brain called the corpus callosum.
Epilepsy (seizure disorder) can occur with a low prevalence in HIVEP2 disorder. From previously published data about 20% have a history of seizures. Seizure severity in HIVEP2 disorder can range from infrequent (once every few years) to frequent (multiple seizures/day).
Distinct facial features
Affected individuals have certain facial features. These include widely spaced eyes, wide bridge of the nose, and tapering fingers.
Vision features
Mild vision features may be common in HIVEP2 disorder. These include strabismus (crossed eyes), farsightedness, and astigmatism.
Gastrointestinal features
Gastroesophageal reflux and constipation are two associated gastrointestinal complications of HIVEP2 disorder.
Miscellaneous
Frequent ear infections may occur with HIVEP2 disorder.
In general, cardiovascular defects are not prominently associated. Kidney, urinary, and genital issues are not a common manifestation of HIVEP2 disorder, though there is one report of vesicoureteral reflux, in which the urine travels from the bladder back into the kidneys (opposite the normal direction).