What is (are) hereditary sensory and autonomic neuropathy type IE ?
Hereditary sensory and autonomic neuropathy type IE (HSAN IE) is a disorder that affects the nervous system. Affected individuals have a gradual loss of intellectual function (dementia), typically beginning in their thirties. In some people with this disorder, changes in personality become apparent before problems with thinking skills.  People with HSAN IE also develop hearing loss that is caused by abnormalities in the inner ear (sensorineural hearing loss). The hearing loss gets worse over time and usually progresses to moderate or severe deafness between the ages of 20 and 35.  HSAN IE is characterized by impaired function of nerve cells called sensory neurons, which transmit information about sensations such as pain, temperature, and touch. Sensations in the feet and legs are particularly affected in people with HSAN IE. Gradual loss of sensation in the feet (peripheral neuropathy), which usually begins in adolescence or early adulthood, can lead to difficulty walking. Affected individuals may not be aware of injuries to their feet, which can lead to open sores and infections. If these complications are severe, amputation of the affected areas may be required.  HSAN IE is also characterized by a loss of the ability to sweat (sudomotor function), especially on the hands and feet. Sweating is a function of the autonomic nervous system, which also controls involuntary body functions such as heart rate, digestion, and breathing. These other autonomic functions are unaffected in people with HSAN IE.  The severity of the signs and symptoms of HSAN IE and their age of onset are variable, even within the same family.