Caecal atresia with sterile abscess formation and perforation in a dog

A 1‐year‐4‐month‐old, male, neutered Rottweiler presented with vomiting, lethargy and abdominal pain. Abdominal radiography identified a mid‐caudal mass effect with reduced serosal detail. Point‐of‐care ultrasound revealed a fluid pocket cranial to the bladder. Cytological evaluation of this fluid demonstrated neutrophilic inflammation without detectable bacteria. Exploratory celiotomy identified an isolated, perforated distal segment of caecum containing thick mucoid material and necrotic debris. A fibrous band separated the lumen of the distal diseased portion from the lumen of the proximal caecum and gastrointestinal tract. Partial typhlectomy was performed. Histopathology confirmed caecal atresia with focal perforation. Bacterial culture was negative, suggestive of a sterile abscess. Recovery was uneventful, with discharge 12 hours post‐operatively and no complications reported at follow‐up at 2 weeks and 7 months. This case describes a rare presentation of caecal atresia in a dog without gastrointestinal obstruction, resulting in sterile abscess formation and peritonitis, successfully managed with surgical intervention.