Familial dysautonomia, also known as Riley Day Syndrome, is a genetic disorder that
affects the development and survival of certain nerve cells. The disorder disturbs
cells in the autonomic nervous system, which controls involuntary actions such as
digestion, breathing, production of tears, and the regulation of blood pressure and
body temperature. It also affects the sensory nervous system, which controls activities
related to the senses, such as taste and the perception of pain, heat, and cold.
Familial dysautonomia is also called hereditary sensory and autonomic neuropathy,
Symptoms of Dysautonomia
Problems related to this disorder first appear during infancy. Early signs and symptoms
include poor muscle tone (hypotonia), feeding difficulties, poor growth, lack of
tears, frequent lung infections, and difficulty maintaining body temperature. Older
infants and young children with familial dysautonomia may hold their breath for prolonged
periods of time, which may cause a bluish appearance of the skin or lips (cyanosis)
or fainting. This breath-holding behavior usually stops by age 6. Developmental milestones,
such as walking and speech, are usually delayed, although some affected individuals
show no signs of developmental delay.
Additional signs and symptoms in school-age
children include bed wetting, episodes of vomiting, reduced sensitivity to temperature
changes and pain, poor balance, abnormal curvature of the spine (scoliosis), poor
bone quality and increased risk of bone fractures, and kidney and heart problems.
Affected individuals also have poor regulation of blood pressure. They may experience
a sharp drop in blood pressure upon standing (orthostatic hypotension), which can
cause dizziness, blurred vision, or fainting. They can also have episodes of high
blood pressure when nervous or excited, or during vomiting incidents.
Dysautonomia is a genetic disorder and is inherited from carriers, who may not show
any signs or symptoms of the disorder.
At present, only supportive treatments are available. Supportive therapies include
medical and surgical options. Various therapies are used to promote strength and