Hereditäre Sensory Autonomic Neuropathie Type 4 and 5, HSAN4, 5 - NTRK1, NGFB

Klinische Symptomatik

Common symptoms of HSAN are loss of nociception and temperature sense combined with autonomous dysfunction. HSAN type 4 patients frequently have recurring fever episodes. This disorder is usually congenital. Children suffer from an analgesia and thermanesthesia, and may therefore hurt themselves easily. Anhidrosis is frequently observed. This disorder is also referred to as Congenital Insensitivity to Pain with Anhidrosis (CIPA). Mental retardation is frequently observed.
HSAN type 5 is more rare and overlaps to a great extent with HSAN type 4. Symptoms may be congenital or develop during early childhood. Loss of nociception and temperature sense is typical; acral ulzerations and fractures are frequent consequences.

Genetik

HSAN 4 is caused by mutations in the NTRK1 gene, which encodes the neurotrophic tyrosin kinase receptor type 1 on chromosome 1q23.1.
HSAN 5 is caused by mutations of the NGFB gene encoding the nerve growth factor beta subunit on chromosome 1p13.1.
HSAN 4 and 5 follow an autosomal recessive pattern of inheritance.