Hereditary sensory and autosomal peripheral neuropathy-type IV: case series and review of literature.

Hereditary sensory and autonomic neuropathy (HSAN) IV is a rare autosomal recessive disorder which is characterized by a decrease in the number of myelinated and non-myelinated nerve fibers of peripheral nerves which causes diminished or absent pain sensation leading to increase in self-mutilative habits. A retrospective study of eight cases ranging from age group of 4 to 17 years for oral and digital signs and symptoms is presented. All the patients showed congenital insensitivity to pain and anhidrosis.