Table 2 Comparison between Friedreich ataxia and Charcot-Marie-Tooth neuropathy type 4C
From: The cerebellar phenotype of Charcot-Marie-Tooth neuropathy type 4C
Features | Friedreich ataxia (FRDA) | Charcot-Marie-Tooth neuropathy type 4C (CMT4C) |
|---|---|---|
Age of onset | Childhood-adolescence | Childhood |
Course of disease | Typically early loss of mobility | Loss of mobility in some |
Prognosis | Reduced life span | Life expectancy unaffected |
Scoliosis | Y (Very common) | Y |
Type of polyneuropathy | Axonal sensory | Demyelinating motor and sensory |
Myokymia | N | Y |
Foot deformity | Y | Y |
Hearing loss | Y (20%) | Y (12%) [3] |
Eye movement abnormalities | Square wave jerks most commonly [12] | Nystagmus in a few patients |
Vestibular signs | Y | Y |
Risk for diabetes | Y (20%) | N |
Hypertrophic cardiomyopathy | Y [13] | N |
Respiratory failure | N | Y |
Cerebellar atrophy | In late stages | Very rare |
Spinal cord atrophy | Y | Unknown |
Other radiological abnormalities | Iron accumulation in the dentate nuclei Atrophy of dentate nuclei [9] | Thickening of cranial nerves |
Pathology of the brain, spinal cord and dorsal roots | Depletion of myelinated fibers in posterior columns, neuronal loss in the dorsal nuclei of Clarke columns thinning of dorsal roots and spinal cord [14], progressive atrophy of the dentate nucleus [15] | Unknown |