Persistent conjunctival papilloma due to oral papillomavirus infection in a rabbit in New Zealand.

ABSTRACT

A 3-yr-old female Flemish Giant pet rabbit developed a papilloma on the right nictitating membrane. Although the papilloma was excised surgically, it promptly recurred. Examination of the eye 10 wk after surgery revealed that in addition to the initial mass, 2 smaller papillomas were present on the lower eyelid. All 3 masses were excised, and histology revealed papillomatous hyperplasia of the conjunctival epithelium, koilocytosis, and intranuclear viral inclusions. Polymerase chain reaction amplified papillomaviral DNA from the largest papilloma. Sequencing of the amplicon revealed 99.3% homology with rabbit oral papillomavirus (ROPV). All 3 masses recurred after removal. In addition, the rabbit was noted to be losing weight. Weight loss continued until the rabbit died 3 mo later. All 3 papillomas persisted until death. This article provides the fi rst description of ROPV causing conjunctival papillomas and is the fi rst report of ROPV from the southern hemisphere. The persistence of the papillomas in this case is also unusual and may suggest that ROPV-induced conjunctival papillomas are less likely than oral papillomas to spontaneously regress. Alternatively, the death of this rabbit may indicate a compromised immune system that allowed papillomaviral persistence.