HISTORY

A 3-kg, nine-years-old, male, Siamese cat was referred to the Hospital Ars Veterinaria emergency service due to acute onset of severe vomiting and dyspnea of 24 hours duration. The cat was feeding an intestinal diet because of chronic small bowel diarrhea with marked weight loss. On physical examination, the cat was thin, tachycardic (heart rate, 230 beats per minute), tachypneic (respiratory rate, 40 breaths per minute) and dyspneic, with episodes of open-mouth breathing. Slightly increased lung sounds, weak femoral pulse and prolonged capillary refill time were detected. Rectal temperature was 36 °C. The abdominal palpation was suggestive of enlarged bowel.

Emergency shock treatment was immediately established. Thoracic survey radiographs were performed. Thoracic film revealed a soft-tissue opacity in the dorsocaudal aspect of the thoracic cavity, in the region of caudal esophagus. The stomach gas bubble was identified within the cranial abdomen with reduction of gastric size. Differential diagnosis included esophageal hiatal hernia, stricture or foreign body, extraluminal masses in the mediastinum or pulmonary parenchyma, and gastroesophageal intussusception.

Despite the treatment, the cat died one hour later. Necropsy was performed and revealed a partial gastroesophageal intussusception. Histopathologic examination of pancreas, spleen, urinary bladder, lungs and liver showed normal features. The renal tissue showed isolated foci of mononuclear cell infiltration and degeneration of the tubular epithelium; the intestinal wall was diffusely infiltrated by a population of lymphoblastic cells with moderate pleomorphism and intermediate mitotic index (2-4 mitosis per high power field). The diagnosis was gastroesophageal intussusception and alimentary lymphoma, with mild renal tubular degeneration.

DISCUSSION

Gastroesophageal intussusception is an uncommon condition in dogs and cats that involves the invagination of the stomach into the distal esophagus. Spleen, duodenum, pancreas and omentum may also be involved. The invagination can be preceded by megaesophagus. Clinical signs include vomiting or regurgitation, dyspnea, hematemesis and abdominal discomfort, usually progressing and culminating in death due to shock and respiratory or vascular compromise. The rapid progression of clinical signs and deterioration of the patient require early diagnosis and treatment. Diagnosis is based on survey radiographs, contrast studies and endoscopic examination. Radiographic signs in survey radiographs consistent with gastroesophageal intussusception include extensive intrathoracic esophageal dilatation; persistent mass effect between the cardiac silhouette and diaphragm; gastric rugal folds within the intrathoracic esophagus on barium examination; and absence or reduction of size of stomach gas shadow in abdomen. In the related clinical case, the survey film let visualize a partial gastroesophageal intussusception, because partial abdominal stomach gas bubble identification.

Therapy includes a brief period of stabilization followed by definitive endoscopic or surgical reduction of the invagination. After the reduction, a left-sided incisional gastropexy is indicated to prevent recurrence. The prognosis is poor unless the disorder is quickly recognized, with mortality rates of 95% reported.

In our case, the condition of gastroesophageal intussusception was early suspected in the initial assessment and recognized after thoracic survey radiographic examination. However, the cat died before definitive surgical treatment could be performed, due to the severity of the clinical signs. Severe vomiting associated with alimentary lymphoma might have allowed the stomach to invaginate into the esophagus. Alimentary lymphoma is characterized by mucosal and submucosal infiltration of neoplastic lymphocytes, which cause malabsorption. Weight loss, vomiting, chronic diarrhea and progressive inappetence are common clinical signs.

In the previous two reported cases of this condition in cats, the gastroesophageal intussusception was secondary to repair of a traumatic diaphragmatic hernia and a chronic intermittent condition associated with idiopathic megaesophagus. In dogs, suggested predisposing factors for gastroesophageal intussusception include chronic vomiting, megaesophagus, esophageal congenital abnormalities, and incompetence of the lower esophageal sphincter.