Unilateral Hypoglossal Neuropathy in Multifocal Acquired Demyelinating Sensory and Motor Neuropathy: Differential Diagnosis of Motor Neuron Disease

Multifocal acquired demyelinating sensory and motor neuropathy (MADSAM) is a peripheral neuropathy characterized by multifocal weakness and associated sensory impairment. MADSAM is associated with multifocal persistent conduction block and other signs of demyelination. The incidence of cranial nerve involvement in MADSAM was recently reported to be approximately 15%. However, reports of hypoglossal neuropathy occurring in MADSAM are rare. Unilateral hypoglossal neuropathy in MADSAM is usually misdiagnosed as motor neuron disease. We report a patient with MADSAM presenting with tongue hemiatrophy.