Clinical features and prognosis of canine megaesophagus in Japan.

Megaesophagus (ME) is a common esophageal disease in dogs and the prognosis is generally poor, especially with aspiration pneumonia (AP). We retrospectively investigated the clinical features and prognosis of canine ME in Japan. Twenty-eight dogs were included in this study, with the Miniature Dachshund breed being significantly overrepresented (odds ratio: 4.33). Most cases (21 of 28) were diagnosed as idiopathic ME and Myasthenia gravis was the most common cause of secondary ME. The overall median survival time (MST) was not reached and the 3-month survival rate was 85.7%. Ten dogs were diagnosed with AP, at least once during the study period, and the MST of ME dogs with AP was 114 days. The survival time overall and even with AP, was notably more prolonged compared to the previous studies. We hypothesized that treatment for canine ME could prolong the survival time, even in those with both ME and AP.