A 9 year old boy is brought in after tripping and falling onto the sidewalk.

His parents mention that he started walking at the age of 18 months, and that he has always been clumsy when walking and running.

He trips and falls over very frequently, and has difficulty getting up from the floor afterwards.

His performance in school is above average. His medical and family histories are unremarkable.

Select Relevant Investigations
NCS + EMG lower limbs


In both lower limbs, there is a marked reduction in the conduction velocities of both sensory and motor nerves, with evidence of denervation of the distal muscles.
CSF Analysis


Appearance: clear
WBC: 3/mm3 (0 - 5)
Protein: 0.2 g/dl (0.15 - 0.4)
Glucose: 80 mg/dl
Random blood glucose: 100mg/dl
Sural nerve biopsy


The biopsy shows a mild loss of myelinated axons. Prominent onion bulb formations are evident upon both light microscopy and ultrastructural examination.
Genetic Analysis


There is duplication of the peripheral myelin protein-22 (PMP22) gene on chromosome 17.

Select Relevant Management
IV Immunoglobulins