Macroglossia in amyotrophic lateral sclerosis

We encountered 2 patients with amyotrophic lateral sclerosis (ALS) with tongue enlargement and protrusion outside the oral cavity (macroglossia). To our knowledge, the relationship between macroglossia and ALS has not been reported in the literature. The objective of this article was to describe the clinical characteristics, imaging, and pathology of macroglossia in ALS and to develop a hypothesis regarding its pathophysiology.

Two patients developed progressive weakness at age 54 and 40 years. Both patients exhibited dysarthria, dysphagia, tongue atrophy, neck extensor weakness, and weakness of jaw closure during a 1-year period. Both required tracheostomy and mechanical ventilation and afterward developed macroglossia. A 3-dimensional-reconstructed sagittal computed tomographic image confirmed tongue protrusion outside the oral cavity with focal compression and showed the transition from the atrophied part of the tongue in the oropharynx to the edematous part outside the mouth. Tongue biopsy demonstrated fatty replacement and fascicles of degenerative muscle.

We are unaware of previous reports of macroglossia in ALS/motor neuron disease. Given the paucity of case material, we speculated that this is an extremely rare complication of ALS. Based on this series, we propose a pathophysiological mechanism by reviewing imaging and tongue biopsy.