• 80% of CMT1 are either 1A or X1
• Definitive results for patient management

Knowing the molecular cause of your patients' CMT is important in prognosis, patient management and family planning

* No gene marker identified
** Gene identified but not yet available

Clinical Reasons for Ordering the CMTI Evaluation Profile:

• Evidence of chronic demyelinating polyneuropathy of unknown origin
• Symmetrically decreased nerve conduction velocity (NCV <40m/sec)
• Patients with slowly progressive distal muscle atrophy and weakness, often with gait disturbance and deformity of feet and hands
• Patients with positive family history; one affected patient or sibling diagnosed with CMT

Case Study

C. M. is a 49 year old woman who contacted the Genetics Department because of a reported family history of Charcot-Marie-Tooth Disease (CMT) and concerns about the risk for her children. Her paternal first cousin was diagnosed at 35 years old by EMG, NCV, and nerve biopsy at another institution. Her paternal aunt and her father had not been formally diagnosed, but both had similar problems, including difficulty walking, weak hands and atrophy of lower legs in late adulthood. The patient was vague about her own symptoms but admitted to fatigue when walking, mild thumb weakness, profuse sweating of hands and feet, and poor temperature regulation.

Physical examination revealed normal muscle bulk and strength except for mild thumb and ankle weakness. There was bilateral pes cavus. Sensory exam revealed slight decrease to touch with bilateral vibration in the feet and absent deep tendon reflexes in the lower extremities. There was profuse sweating of the palms and soles. The patient initially deferred an NCV study due to denial about her symptoms. A differential diagnosis of idiopathic neuropathy was made. Electrophysiologic studies were eventually done and confirmed a moderately severe, fairly symmetrical demyelinating generalized sensorimotor peripheral neuropathy. DNA analysis on the patient revealed the characteristic CMT1A duplication.

As a result of the clinical evaluation and molecular testing, the patient was definitively diagnosed with CMT1A. Her at-risk children are aware of their status and can undergo diagnostic evaluation by molecular studies rather than invasive and uncomfortable neurophysiologic testing.

Ordering Information:

• Ship overnight, whole blood in 3 yellow top ACD solution A tubes, Monday through Thursday only.
  
• Call Athena Diagnostics client services at 1-800-394-4493 for shipping kits and further information.