Renal abscess in a Lionhead rabbit due to Encephalitozoon cuniculi and Escherichia coli: A case report.

Background: In rabbits, renal abscesses (pus-filled sores) are rare and diagnosis remains challenging. Therefore, in this study, we aimed to determine the clinical manifestation and diagnostic tests associated with renal abscess identification in rabbits.

Case description: A four-and-a-half-year-old castrated male Lionhead rabbit with a history of poor appetite and abdominal distension was admitted to the animal hospital. Blood analysis, radiography, ultrasonography, and computed tomography scans revealed a kidney abscess found within the renal parenchyma, with severe loss of the cortex and medulla, extending toward the capsule. Consequently, the rabbit underwent nephrectomy. The enlarged right kidney was surgically removed. Histopathological examination of the affected kidney showed severe necrosis and ischemic zones, atrophy of the renal tubules, and prominent heterophils with mixed inflammatory cell infiltrates. Immunohistochemistry and polymerase chain reaction confirmed Encephalitozoon cuniculi and Escherichia coli infections, respectively.

Conclusion: This report provides novel insights into the diagnosis of renal abscesses in Lionhead rabbits.