Sensory CIDP presenting as cryptogenic sensory polyneuropathy

The objective of this study was to report that patients with chronic inflammatory demyelinating polyneuropathy (CIDP) can present with a clinical picture of cryptogenic sensory neuropathy. Patients with distal sensory neuropathy and electrodiagnostic studies that are minimally abnormal or consistent with an axonal pathology are usually diagnosed as having cryptogenic sensory neuropathy if no cause for neuropathy can be found. Some of these patients, however, may have sensory CIDP. We reviewed the records of eight patients with CIDP, diagnosed by sural nerve biopsy, who presented with sensory neuropathy and electrodiagnostic studies that were minimally abnormal or revealed changes consistent with axonal neuropathy. All patients reported distal numbness and paresthesias and, on examination, had predominantly large fiber distal sensory loss and normal muscle strength. In most patients, deep tendon reflexes were reduced or absent. Sural nerve biopsies in all patients were consistent with chronic myelinopathy, with quantitative teased fiber analysis revealing segmental remyelination in 13-40% of the fibers. The four patients who received IVIg therapy had improved sensation and gait. Of the remaining four patients, one is being followed, one had spontaneous remission, one was lost to follow-up, and one, with contraindications to therapy, reported disease progression. Sensory CIDP may present as cryptogenic sensory polyneuropathy with normal or axonal electrophysiologic features. Sural nerve biopsy should be considered in patients with progressive, predominantly large fiber sensory neuropathy of otherwise unknown etiology, as they may have sensory CIDP that responds to therapy.