[Dysautonomia. A clinical study of a case, ultrastructural data].

We report a new case of non-familial dysautonomia. The patient was a boy with no known Jewish ancestry in whom psychomotor retardation in early infancy failed to lead to specialized evaluation. Regressive episodes of ataxia developed at the age of three and infrequent generalized seizures occurred between four and seven. Diagnosis was first considered at the age of seven after neuroparalytic keratitis developed and rapidly became bilateral. This case has remained highly unusual throughout the course since none of the commonly reported complications (swallowing disorders, aspiration pneumonia, and dysautonomic "attacks") has occurred. No life-threatening manifestations have developed. Peripheral nerve biopsy specimens showed that myelinated fibers, especially of large diameters, were abnormally scarce, and that the histogram failed to exhibit the normal bimodal aspect. Ultrastructural studies also disclosed a marked reduction in the caliber of unmyelinated fibers, whose axons were flattened or occasionally missing. No evidence of regeneration was found. The atypical clinical features in our patient are discussed.