Abstract

Hereditary sensory and autonomic neuropathies (HSAN) are disorders of hereditary neuropathy mainly affecting sensation and also accompanying autonomic nervous system dysfunction. They are divided into five subtypes based on inheritance pattern and clinical manifestation. Among HSAN, type II is characterized by autosomal recessive inheritance, presentation at later stage of life, slow progression and mainly sensation abnormalities. The main pathology of the peripheral nerve is the absence of myelinated nerve fibers. Type IV is very rare disorder and only a few cases have been reported. It is characterized by autosomal recessive inheritance, presentation at birth as failure to thrive, retarded motor development, unexplained pyrexia and rapidly progressive and severe clinical course. The main pathology of the peripheral nerve is a loss of unmyelinated and small myelinated nerve fibers. We report two cases of type IV and one case of type II especially focusing on ultrastructural findings, which are characteristic of and diagnostic for HSAN.

• Keywords: Peripheral nerve;Hereditary sensory & autonomic neuropathy;Pathology;Ultrastructure;