Congenital insensitivity to pain and anhidrosis: a case report from South India.

Congenital insensitivity to pain with anhidrosis, also known as hereditary sensory and autonomic neuropathy type IV, is an autosomal recessive disorder characterized by the congenital lack of pain sensation, inability to sweat, episodes of recurrent hyperpyrexia, mental retardation, and self-mutilating behavior. It is an extremely rare disorder with only a handful of reports from India. A five- year- old boy, born to second-degree consanguineous parents after uneventful antenatal period, presented to us with history of recurrent unexplained fever, recurrent ulcers in the lower limbs, insensitivity to painful stimuli (like injections, vaccination) and self-mutilating behavior from early childhood. Cutaneous examination showed multiple ulcers, loss of teeth, loss of tip of the tongue (due to biting), scarring of finger tips, xerosis and lichenification. Sensory examination showed complete loss of pain and temperature sensations, but fine touch and vibration were preserved. Deep tendon reflexes were normal. Evaluation for Hansen's disease was non-contributory. An intradermal injection of histamine did not show any flare response. Based on clinical as well as compatible histological features a diagnosis of congenital insensitivity to pain with anhidrosis was made. The ulcers were treated with appropriate antibiotics and daily dressings. The parents were counseled about appropriate care of the child.