Clinical profile of Monomelic Amyotrophy (MMA) and role of persistent viral infection.

OBJECTIVES: The objective of our study was to describe the clinical characteristics, electrophysiology, MRI features and conduct viral assays in patients with Monomelic Amyotrophy (MMA) and follow them up over one year.

METHODS: Consecutive patients with MMA who attended the Neurology services from April 2013 to March 2014 were included. Age and sex matched controls were taken for the purpose of viral assay analysis. The clinical evaluation was repeated at six months and one year.

RESULTS: 109 cases and 109 controls were included in the study. The patients were predominantly males (98.2%; n=107/109) and had involvement of upper limbs (83.5%; n=91/109). 26 (23.8%) patients with clinically unilateral involvement had bilateral neurogenic changes in the electromyography. Serological assays of Japanese E, West Nile Virus, and Poliovirus 1, 2 and 3, HIV 1 and 2 were negative in all the cases and controls.

CONCLUSIONS: Patients with MMA are predominantly young males with upper limb wasting and weakness. MRI of the cervical cord is normal in most of the patients (67.9%). The present study did not find any evidence of the association of viral infection in MMA.