Abstract

Background: Oesophageal motility, as measured by manometry, is normal in the majority of patients with eosinophilic oesophagitis (EO). However, manometry measures only the circular muscle function of the oesophagus. The goal of the present study was to assess circular and longitudinal muscle function during peristalsis in patients with EO.

Methods: Ultrasound imaging and manometry were simultaneously acquired during swallow-induced peristalsis in patients with EO and controls to measure the longitudinal muscle and circular muscle contraction, respectively. A probe with an ultrasound transducer was positioned 2 cm and then 10 cm above the lower oesophageal sphincter and five, 5 ml water swallows were recorded before and after edrophonium.

Results: There is no difference in the incidence of swallow-induced peristalsis and manometric pressures (a marker of circular muscle contraction) between controls and patients with EO. However, changes in the muscle thickness (a marker of longitudinal muscle contraction) are markedly diminished in patients with EO, at both 2 and 10 cm above the lower oesophageal sphincter. The longitudinal muscle response to edrophonium is markedly blunted in patients with EO. Normal subjects demonstrate synchrony between the circular and longitudinal muscle contraction during peristalsis that is affected by edrophonium. On the other hand, patients with EO demonstrate mild asynchrony of circular and longitudinal muscle contraction during swallow-induced contractions that is not altered by edrophonium.

Conclusions: In patients with EO, there is selective dysfunction of the longitudinal muscle contraction during peristalsis. It is proposed that the longitudinal muscle dysfunction in EO may contribute to dysphagia.