Objective:

To explore the clinical presentation linking FIG4 mutation between Charcot-Marie-Tooth Disease and Parkinsonism.

Background:

Charcot-Marie-Tooth Disease(CMT) is a hereditary neuropathy associated with many gene mutations, including the FIG4 gene.  There have been some case reports identified of a potential link between FIG4 and developing Parkinsonism, which raises question if there is a shared relationship between the gene and neurodegeneration.

Design/Methods:

N/A

Results:

A 50 year old female with a history of Hereditary neuropathy with Liability to Pressure Palsies(HNPP) presented to the clinic with bilateral foot pain and right arm weakness.  Neurological examination was significant for diminished reflexes, sensory deficits in a glove and stocking distribution, and minor bradykinesia.  EMG was performed, showing markedly prolonged conduction velocities with conduction blocks, suggesting a demyelinating disease.  Lumbar Puncture was pursued, which revealed normal protein levels, and negative Contactin and Fasicin antibodies.  Repeat genetic testing revealed negative results for HNPP, however there was a positive FIG4 gene mutation, consistent with Charcot-Marie-Tooth Disease(CMT) type 4.  On follow up, the patient developed a resting tremor in the left leg, and worsened bradykinesia.  Dopamine Transporter Scan revealed abnormal dopamine uptake.  She was started on Carbidopa-Levodopa with improvement of her tremor. 

Conclusions:

This case illustrates the coexistence of CMT type 4 and Parkinsonism in a patient with FIG4 mutation.  From a literature review, there are a few cases reported of patients with FIG4 mutation and co-morbid CMT type 4 and Parkinsonism.  Further research is warranted to explore the relationship of FIG4 to these two diseases, as this may provide insight into underlying mechanisms between both conditions.