Liver lobe torsion in a Shih‐tzu dog

Abstract

MADAM We write to report a case of liver lobe torsion (LLT) in a small breed dog where ultrasound and computed tomography (CT) were useful in diagnosis of the condition. A 3-year-old male shih-tzu was presented with abdominal pain and acute onset vomiting, followed by progressive weakness. On examination the abdomen was tense and a firm painful mass was palpated cranially. Haematology and biochemistry profiles showed elevated liver enzymes, mild anaemia, and mild thrombocytosis. Abdominal radiographs showed a triangular mass in the cranial abdomen to the left of midline and caudal to the liver displacing the small intestine and the left kidney caudally. An abdominal ultrasound revealed a small volume of anechoic peritoneal effusion and an enlarged, homogenous, and hypoechoic left liver lobe. No blood flow was seen in the vessels including the hepatic veins and the portal veins within this liver lobe. Four detector-row CT was performed without anaesthesia. Pre-contrast CT revealed enlargement and caudoventral deviation of the left liver lobe with an irregular surface. Hypodense free fluid was present in the peritoneum. Post-contrast images showed no change in density of the abdominal left liver but normal contrast enhancement was seen in the remainder of the hepatic parenchyma (Figs 1A and 1B). A dorsal-plane image showed fissures on the liver surface, supporting rupture of the liver (Fig 1C, arrows). A diagnosis of LLT was made based on the imaging findings. Pre-contrast (A) and post-contrast (B,C) CT images through the cranial abdomen reveal an enlargement of the left lateral (LL) and left medial (LM) liver lobe without contrast enhancement. On dorsal-plane image, there are fissures on the liver surface (arrows) After a transfusion of whole blood, an exploratory laparotomy was performed. At surgery, 180 degree torsion of the left medial and left lateral liver lobe was identified and haemorrhagic peritoneal effusion and parenchymal rupture were present. A lobectomy of the affected regions was performed. The patient awoke from the anaesthesia, but died six hours after surgery. The cause of death was suspected to be severe postoperative complications. Most previous reports of LLT in dogs occurred in large breeds (Swann and Brown 2001, Schwartz and others 2006) and a few medium-sized breeds including the beagle (Sonnenfield and others 2001). To the author’s knowledge, this is the first case reported in such a small breed dog. Furthermore, this is the first report of the use of CT in diagnosis of the condition. Multiplanar reconstructions are particularly useful in assessment of complex anatomical abnormalities such as lung lobe torsion, and in this case, LLT. Liver lobe torsion, though very rare, should be considered in the differential diagnosis for acute abdominal pain, even in small breed dogs.