Summary about Disease
Riley-Day syndrome, also known as familial dysautonomia or hereditary sensory and autonomic neuropathy type III (HSAN III), is a rare genetic disorder that primarily affects the development and function of the autonomic nervous system and the sensory nervous system. The autonomic nervous system controls involuntary functions such as heart rate, blood pressure, body temperature, digestion, and sweating. The sensory nervous system is responsible for sensing pain, temperature, and touch. This dysfunction can lead to a wide range of symptoms affecting multiple systems of the body.
Symptoms
Symptoms vary widely in severity and can include:
Feeding difficulties in infancy
Poor weight gain
Lack of tears
Unstable body temperature
Blood pressure instability
Gastrointestinal problems (vomiting crises, constipation)
Pneumonia
Swallowing difficulties
Speech problems
Skeletal abnormalities (scoliosis)
Reduced sensitivity to pain and temperature
Absent or diminished reflexes
Drooling
Emotional lability
Causes
Riley-Day syndrome is caused by mutations in the ELP1 gene (also known as *IKBKAP*) located on chromosome 9. This gene provides instructions for making a protein called Elongator complex protein 1, which is involved in nerve cell development and function. The mutations lead to a reduced amount of functional Elongator complex protein 1, disrupting the normal development and function of the nervous system. It is inherited in an autosomal recessive pattern, meaning both parents must carry a copy of the mutated gene for their child to be affected.
Medicine Used
There is no cure for Riley-Day syndrome. Treatment is focused on managing individual symptoms and improving quality of life. Medications may include:
Medications to manage blood pressure (e.g., beta-blockers, fludrocortisone)
Anti-reflux medications for gastrointestinal issues
Laxatives for constipation
Antibiotics for infections
Sedatives for vomiting crisis
Is Communicable
No, Riley-Day syndrome is not communicable. It is a genetic disorder and cannot be spread from person to person.
Precautions
Precautions for individuals with Riley-Day syndrome and their caregivers include:
Careful monitoring of vital signs (temperature, blood pressure, heart rate)
Preventing dehydration and overheating
Protecting from injury due to reduced pain sensitivity
Managing feeding difficulties and ensuring adequate nutrition
Preventing aspiration during feeding
Regular monitoring by a multidisciplinary team of healthcare professionals
How long does an outbreak last?
There are no "outbreaks" associated with Riley-Day syndrome. The condition is chronic and lifelong, requiring ongoing management of symptoms. A vomiting crisis or other symptom exacerbations may occur acutely and last hours to days, requiring specific medical intervention.
How is it diagnosed?
Diagnosis typically involves:
Clinical evaluation based on the presence of characteristic symptoms.
Genetic testing to identify mutations in the ELP1 gene.
Histamine skin test (reduced or absent flare response).
Neurological examination.
Tear production test (Schirmer test).
Timeline of Symptoms
Symptoms often manifest in infancy or early childhood.
Infancy: Feeding difficulties, poor weight gain, lack of tears, temperature instability.
Early Childhood: Vomiting crises, pneumonia, developmental delays, speech problems.
Childhood/Adolescence: Scoliosis, blood pressure instability, gastrointestinal issues.
Throughout Life: Symptoms persist and require ongoing management.
Important Considerations
Riley-Day syndrome requires comprehensive, multidisciplinary care from specialists familiar with the condition.
Early diagnosis and intervention are crucial for improving outcomes.
Genetic counseling is recommended for families with a history of the disorder.
Support groups and advocacy organizations can provide valuable resources and information.
Research is ongoing to better understand the disorder and develop new treatments.