First report of nodular hyperplasia in the spleen of a horse

Abstract A 23‐year‐old American Saddlebred mare was presented to the equine emergency service due to colic signs. Small intestinal strangulation was suspected via abdominal ultrasound. Due to the poor prognosis, the patient was euthanased and submitted for postmortem examination, which confirmed the clinical diagnosis of small intestinal strangulation due to a mesenteric lipoma. In addition, multiple raised nodules ranging in size from 0.2 to 2.3 cm in diameter were found in the spleen. Histological examination was consistent with incidental nodular hyperplasia in the spleen. Although it is well described in dogs, nodular hyperplasia in the spleen has not been documented in horses previously. It should be considered a potential differential diagnosis for splenic nodules that may rupture and cause haemoperitoneum, sudden collapse and eventually death of the horse, as seen in dogs.