USING SILDENAFIL TO TREAT A DOG WITH IDIOPATHIC MEGAESOPHAGUS

Abstract

A 4-month old, male intact, mixed-breed dog was referred for sudden onset of regurgitation for two weeks. Thoracic radiographs revealed severe dilatation of esophagus with barium aspiration pneumonia. Idiopathic megaesophagus (IME) was diagnosed after serial laboratory, endoscopic and computed tomographic examinations. Symptomatic treatment including medication for pneumonia, feeding through percutaneous endoscopic gastrostomy (PEG) tube with upright feeding position was performed at first, but regurgitation persisted. Sildenafil (1[Formula: see text]mg/kg, PO, BID) was then administrated for two weeks and regurgitation remitted one day after. Sildenafil was then tapered to half dose (0.5[Formula: see text]mg/kg, PO, BID) for another two weeks. During following-up thoracic radiography on 10 days after sildenafil administration, the degree of esophagus dilation significantly reduced. The clinical sign was completely resolved without relapse for more than 300 days. Sildenafil was reported having inhibitory effect of canine gastric contraction without affecting gastric emptying time. This effect could ameliorate persisting regurgitation after using PEG feeding directly into the stomach while bypassing the esophagus.