Atypical course of Charcot-Marie-Tooth disease: what shall we be thinking of?

Abstract

Charcot-Marie-Tooth disease (CMT) is an inherited polyneuropathy with a gradually progressive course. Atypical features such as acute or subacute deterioration and unusual electrophysiological findings should be alarming. A 54 year-old woman with medical history of hypothyroidism, was referred to our department for weakness of her 4 limbs with a subacute onset and rapid worsening. The family history was marked by feet deformities. The pedigree was suggestive of autosomal dominant inheritance. On examination the proband had steppage gait, with distal muscle weakness in four limbs, absent tendon reflexes, hummer toes and hollow feet. Nerve conduction studies showed homogeneous demyelination but with temporal dispersion in motor nerves. We noted slight increase in protein level in cerebrospinal fluid (CSF). The patient was diagnosed with autosomal dominant CMT type I based on family history, neurological examination of the proband and her relatives, and electrophysiological findings, associated with chronic inflammatory demyelinating polyneuropathy. The patient was treated with high-dose steroids and than moderately improved. Further reported features suggesting a co-existent hereditary and inflammatory process are: conduction blocks in motor nerve conduction studies, high protein levels in CSF, evidence of inflammatory process in nerve biopsy and nerve root enhancement in spinal imaging. Atypical course and unusaul biological, electrical and imaging features in CMT disease should be alarming about the co-existence of inflammatory neuropathy. Immunomodulatory treatment may substancially improve the outcome.