Quantitative assessment of lingual strength in late-onset Pompe disease.

INTRODUCTION Skeletal muscle is common in late-onset Pompe disease (LOPD). Recent data implicate common bulbar muscle involvement (i.e., the tongue). METHODS We used quantitative assessment of lingual strength to retrospectively determine the frequency and severity of lingual weakness in LOPD. We additionally examined associations between lingual strength and the presence or absence of dysarthria, and dysarthria severity. RESULTS Quantitative assessment revealed lingual weakness to be present in 80% of the sample. In the 24 affected patients, severity was mild in 29%, moderate in 29%, and severe in 42%. Patients with clinical dysarthria had greater lingual weakness than those without. As dysarthria severity increased, lingual strength decreased by an average of 6.82 kPa. CONCLUSIONS These quantitative data provide additional evidence for presence of bulbar muscle disease in patients with LOPD. Further study is necessary to determine functional effects, temporal progression, and effects of treatment.