Sensory and autonomic neuropathy in patients with idiopathic slow-transit constipation

Background: Slow-transit constipation (STC) is a severe disorder of unknown aetiology, which may result from an autonomic or sensory neuropathy. This study aimed to investigate patients with STC for the presence of neural dys function, and relate the findings to other factors, including any familial associations. Methods: Thirty-three patients with STC were studied using standard neuroph ysiological tests and a range of quantitative sensory and autonomic tests. The findings were compared with those of 20 matched control subjects and ni ne diabetic patients with gastrointestinal symptoms. Results: Twenty of the 33 patients with STC gave a family history of consti pation, including an affected identical twin and Hirschsprung's disease (n = 3). None had abnormalities on neurological examination or nerve conductio n studies. Fifteen of the 33 patients had abnormalities on quantitative tes ts, including all six who required a colectomy. Eleven patients with STC ha d reduced axon-reflex sweating in the presence of normal sweat gland respon ses (P < 0.001, all patients with STC versus controls). Twelve patients wit h STC had small sensory fibre dysfunction, with significantly increased the rmal thresholds (cool, P < 0.05; warm, P < 0.01); these included six of nin e patients with STC and rectal hyposensation. There were similar findings o n quantitative testing in diabetic patients. Conclusion: Quantitative tests in patients with STC provide evidence of a s mall fibre neuropathy. The high incidence of a positive family history, par ticularly a possible association with Hirschsprung's disease, suggests a ge netic basis, which deserves further investigation.