Hereditary sensory and autonomic neuropathy 4

Hereditary sensory and autonomic neuropathy 4 (HSAN4), also known as Congenital insensitivity to pain with anhidrosis (CIPA), is a rare genetic disorder characterized by the inability to feel pain and temperature, and decreased or absent sweating (anhidrosis). This condition is one of the many types of Hereditary sensory and autonomic neuropathy (HSAN), a group of related genetic syndromes that cause widespread nerve dysfunction.

Genetics

HSAN4 is caused by mutations in the NTRK1 gene, which provides instructions for making a protein essential for the survival of nerve cells. The mutations prevent the cells from making functional NTRK1 protein, leading to the death of the nerve cells that transmit pain, temperature, and touch sensations from the skin and other tissues to the brain.

Symptoms

The symptoms of HSAN4 usually become apparent at birth or during infancy. Affected individuals are unable to feel pain and temperature and have little to no sweating. This can lead to an accumulation of injuries and health issues such as self-mutilation, bone fractures, and skin ulcers. Other symptoms may include intellectual disability, behavioral problems, and growth delay.

Diagnosis

The diagnosis of HSAN4 is based on clinical features, family history, and genetic testing. The genetic testing can confirm the presence of mutations in the NTRK1 gene.

Treatment

There is currently no cure for HSAN4. Treatment is symptomatic and supportive, focusing on managing the symptoms and preventing complications. This may include regular medical check-ups, use of protective devices to prevent injuries, and physiotherapy to improve mobility and strength.

See also

• Hereditary sensory and autonomic neuropathy
• NTRK1
• Genetic disorder
• Pain

NIH genetic and rare disease info

• NIH info on Hereditary sensory and autonomic neuropathy 4

Hereditary sensory and autonomic neuropathy 4 is a rare disease.