62 yo female presented with gradually progressive numbness in the feet for 3 years, and numbness and paresthesia as well as fine tremors in the hands for one year. She did not complain of weakness or neuropathic pain. There was H/O chronic, treated, hypothyroidism and bilateral CTS release 20 years before. Exam showed that mental status, speech, language and cranial nerves were normal. There was normal tone, bulk and muscle strength. The vibratory sensation was impaired vibration at toes, ankles and fingertips. Priorioception was impaired at the toes, and pinprick was impaired in a stocking-glove distribution up to lower shins and fingertips. Reflexes were diffusely attenuated and absent at the ankles. Romberg’s test was positive and she had difficulty with tandem gait.

Labs: ANA 1280, SS-A 24. CBC, CMP, TSH, B12, hepatitis panel, RPR, anti DS-DNA, Smith, SS-B, RF, Ganglioside panel were normal. Serum protein immunoelectrophoresis showed a monoclonal IgM and elevated IgM level (705 mg/dl , normal 53-330 ). Skeletal survey was negative and bone marrow biopsy and abdominal fat aspirate were negative for malignancy or amyloidosis. Click here for EMG and nerve conduction study.

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