Congenital Insensitivity to Pain With Anhidrosis: A Case Report and Review of the Pertinent Literature.

Congenital insensitivity to pain with anhidrosis, or hereditary sensory and autonomic neuropathy (HSAN) type IV, is an exceedingly rare neurogenetic disorder. Reported causes are homozygous or compound heterozygous loss-of-function mutations in the neurotrophic tyrosine receptor kinase 1 gene (NTRK1). Characteristically, patients with this disorder exhibit a complete diminution of pain and temperature sensations over the body disrupted sweat gland functioning, and variable degrees of sensation and cognitive impairments. We hereby present the clinical and neurophysiologic features of a 15-month-old boy with a homozygous frameshift mutation in c.1860_186insT. (p.Pro621Serfs*12) in the NRTK1 gene, consistent with the diagnosis of congenital insensitivity to pain with anhidrosis.