Chronic acquired sensory neuron diseases

Sensory neuron diseases (SND) represent a specific subgroup of peripheral nervous system disorders that are becoming increasingly recognized. We aimed to analyze clinical, neurophysiological, and MRI features in patients with SND.

We reviewed clinical and electrophysiological data of 20 individuals fulfilling SND criteria. Patients underwent an additional neurological evaluation and cervical spine MRI.

Sensory neuron diseases was associated with dysimmune conditions in six, hepatitis C in one, B12 deficiency in another, and in one patient SND was related to organophosphate intoxication. In the remaining eleven, it was considered as idiopathic. Nineteen patients experienced sensory symptoms. Worse ataxia was related with longer disease duration (P = 0.02). Early CSF assessment was related to higher protein level (P = 0.008). All patients showed widespread impairment in sensory nerve action potential amplitudes. High signal intensity in the posterior columns was observed in most patients when MRI was performed more than 3 years after disease onset.

Sensory neuron diseases usually presents with sensory symptoms and ataxia. A high index of suspicion is important because inflammatory changes might be more prominent initially, a period when immunotherapy could be more valuable. Early diagnosis should be based mainly on electrophysiological and clinical grounds, as MRI may be normal initially.