SENSORY CHRONIC INFLAMMATORY DEMYELINATING POLYNEUROPATHY: AN UNDER-RECOGNIZED ENTITY?

IntroductionSensory chronic inflammatory demyelinating polyneuropathy (CIDP) can be difficult to diagnose. MethodsWe report 22 patients with chronic sensory polyneuropathy with 1 clinical sign atypical for chronic idiopathic axonal polyneuropathy (CIAP) but no electrodiagnostic criteria for CIDP. ResultsClinical signs atypical for CIAP were: sensory ataxia (59%), generalized areflexia (36%), cranial nerve involvement (32%), rapid upper limb involvement (40%), and age at onset 55 years (50%). Additional features were: normal sensory nerve action potentials (36%), abnormal radial/normal sural pattern (23%), abnormal somatosensory evoked potentials (SSEPs) (100%), elevated cerebrospinal fluid (CSF) protein (73%), and demyelinating features in 5/7 nerve biopsies. Over 90% of patients responded to immunotherapy. We conclude that all patients had sensory CIDP. ConclusionsSensory CIDP patients can be misdiagnosed as having CIAP. If atypical clinical/electrophysiologic features are present, we recommend performing SSEPs and CSF examination. Nerve biopsy should be restricted to disabled patients if other examinations are inconclusive.