Congenital Liver Cyst in a Neonatal Calf

Congenital serous cysts attached to the liver capsule are usually small and multiple, but can be solitary, grow extremely large, and become symptomatic. They are considered rare incidental findings during laparotomies or necropsies and thier occurrence is well described in the human literature, with limited reports from the veterinary literature. This report describes the ante-mortem diagnosis and successful surgical removal of a large congenital liver cyst in a neonatal calf. 1. Introduction Congenital serous cysts are attached to the capsule of the liver and have been reported in many different species and are considered rare incidental findings during laparotomies or necropsies [1]. These cysts are usually small and multiple, but can be isolated and grow extremely large and become symptomatic [2]. Their occurrence is well described in the human literature, with limited reports from the veterinary literature [3, 4]. This report describes the ante-mortem diagnosis and successful surgical removal of a congenital liver cyst in a neonatal calf. 2. Case Presentation A 2-week-old Angus bull calf presented to the University of California Davis Veterinary Medical Teaching Hospital for weakness. On physical examination the calf had a fever (103.3？F), tachycardia (156？bpm), tachypnea (84？bpm), and an enlarged, pendulous abdomen. Abnormalities on blood work included neutropenia (1478/μL; ref. 2300–6800/μL), monocytosis (1,003/μL; ref. 0–900/μL), thrombocytosis (981,000/μL; ref. 233,000–690,000/μL), and mild hypoalbuminemia (3？g/dL; ref. 3.1–4.3？g/dL). Ultrasound exam of the abdomen was performed and revealed a large, fluid filled structure occupying the entire ventral abdomen, measuring 23？cm × 25？cm (Figure 1). It contained slightly echogenic fluid and was in direct contact with the liver in the cranioventral abdomen. The liver demonstrated normal size, margins, echogenicity, and vascularity. The left and right kidneys, the spleen, and the gastrointestinal structures was all within normal limits. Figure 1: Ultrasound image obtained from the right cranioventral abdomen using a 3–9？MHz “microconvex” curvilinear transducer at a depth of？？13.6？cm. The large cyst (arrows) can be seen originating from the right liver lobe. A cyst originating from the liver or peritonitis with adhesions to the liver were considered most likely. Aspiration of the fluid filled structure was performed and yielded serosanguinous fluid with low cellularity (50？cell/μL). Cytological evaluation revealed nucleated cells consisting predominantly of foamy macrophages, along with a few reactive