Hereditary Sensory and Autonomic Neuropathies

The hereditary sensory and autonomic neuropathies (HSAN) are a group of rare, clinically and genetically heterogeneous disorders. A numerical classification (type I to V) based on clinical phenotype and pattern of inheritance is widely used but additional entities have been described. With the exception of HSAN type I, which has a dominant pattern of inheritance, all other HSANs are autosomal recessive traits. Diagnosis of the HSANs depends on clinical examinations and detailed sensory and autonomic assessments. In recent years, identification of specific genetic mutations for some of the HSANs has allowed confirmation of the diagnosis and a more genotype-based disease classification. There is still no cure for any of the HSANs but clinical trials of potential disease modifying therapies are under way in HSAN I and III. In the meantime, treatment is supportive and directed toward specific symptoms.