Vici syndrome - Genetics Home Reference - NIH

Vici syndrome - Genetics Home Reference - NIH





Vici syndrome

Vici syndrome is a severe disorder that begins early in life and affects many body systems. It is characterized by abnormalities of the brain, immune system, heart, skin, and eyes. Other organs and tissues are less commonly affected.

A characteristic feature of Vici syndrome is a brain abnormality called agenesis of the corpus callosum, in which the tissue that connects the left and right halves of the brain (the corpuscallosum) fails to form normally during the early stages of development before birth. Other brain abnormalities can occur in Vici syndrome, including underdevelopment of a region of the brain known as the pons (pontine hypoplasia) and reduced myelin, which is a fatty substance that covers and protects nerve cells. In addition to problems with brain development, breakdown (degeneration) of brain tissue may occur over time, resulting in an unusually small head size (microcephaly).

The brain problems contribute to profound developmental delay in individuals with Vici syndrome. Affected infants have weak muscle tone (hypotonia). Few are able to roll, and they may lose this skill when they get older. None are able to sit or walk. In addition, affected children cannot speak.

Another characteristic feature of Vici syndrome is impaired immune function (immune deficiency), which leads to recurrent infections that can be life-threatening. Respiratory infections are most common, and gastrointestinal and urinary tract infections are frequent.

A potentially life-threatening heart condition called cardiomyopathy is common in children with Vici syndrome. This condition, which worsens over time, makes it difficult for the heart to pump blood efficiently. Some affected children also have heart defects that are present from birth (congenital).

Other key features of Vici syndrome include skin and hair that are lighter in color than that of family members and other people with the same ethnic background (hypopigmentation), and clouding of the lenses of the eyes (cataracts) or other eye abnormalities, which may reduce vision.

Other, less-common signs and symptoms of Vici syndrome include seizures; hearing loss caused by abnormalities of the inner ear (sensorineural hearing loss); an opening in the upper lip (cleftlip) with or without an opening in the roof of the mouth (cleft palate) or other unusual facial features; and abnormal function of the thyroid, liver, or kidneys. Many affected infants grow and gain weight more slowly than expected.

Due to the severity of the condition, most people with Vici syndrome do not survive beyond age 5.