Congenital insensitivity to pain with anhidrosis is an autosomal-recessive disorder resulting from defective neural crest differentiation with loss of the first-order afferent system, which is responsible for pain and temperature sensation. There is also a neuronal loss in the sympathetic ganglia. Lack of sweating, hyperthermia, and infections of bones are main features of the disorder; however, contradictory results have been published regarding eccrine sweat gland innervation. A 5-year-old male patient with typical clinical manifestations of congenital insensitivity to pain with anhidrosis is presented. Immunohistochemistry with antibodies against S100 protein and neuron-specific enolase failed to reveal nerve fibers in the vicinity of the eccrine sweat glands. The roles of the nerve growth factor and tyrosine kinase receptor gene mutations in the pathogenesis of the disease are also discussed.