JPC SYSTEMIC PATHOLOGY
Signalment (JPC# 1367008): A bull
HISTOPATHOLOGIC DESCRIPTION: Prepuce: Multifocally the epidermis is eroded or ulcerated and the subjacent dermis is infiltrated by numerous viable and degenerate neutrophils, fewer lymphocytes, plasma cells, and macrophages admixed with eosinophilic cellular and karyhorrectic debris, fibrin, and edema. Immediately adjacent to the ulcers, keratinocytes within the stratum spinosum are separated by increased clear space with prominent intercellular bridges (spongiosis), and are swollen up to 2 times normal size with pale, eosinophilic cytoplasm (intracellular edema). Occasionally nuclei within the epidermis contain irregular, round to oval, eosinophilic to amphophilic, 5-7 um diameter viral inclusion bodies, which either fill the nucleus and/or marginate the chromatin and are rimmed by a clear halo. Diffusely within the dermis, immediately subjacent to the dermoepidermal junction there are high numbers of lymphocytes and plasma cells. Multifocally away from the ulcers, there is neutrophilic exocytosis through the epidermis. Dermal blood vessels are multifocally lined by plump, reactive endothelial cells and contain moderate numbers of transmigrating neutrophils, and dermal collagen is mildly separated by clear space (edema).
MORPHOLOGIC DIAGNOSIS: Prepuce: Posthitis, ulcerative, subacute, multifocal, moderate, with epithelial eosinophilic intranuclear viral inclusion bodies, breed unspecified, bovine.
ETIOLOGY: Bovine herpesvirus-1
ETIOLOGIC DIAGNOSIS: Herpesviral posthitis
- Alphaherpesvirus, DNA-virus
- BHV-1 causes infectious bovine rhinotracheitis (IBRV), infectious pustular vulvovaginitis (IPVV) and infectious balanoposthitis
- The different syndromes rarely occur simultaneously
- Caused by different subgroups: Subgroup 1 – IBRV, Subgroup 2 – IPVV/balanoposthitis, and Subgroup 3 - neurotropic
- All syndromes can result in abortion, mostly in the last trimester
- Terms: Phallitis – inflammation of the penis; balanitis – inflammation of the glans penis; posthitis – inflammation of the prepuce; phaloposthitis or balanoposthitis – inflammation of the penis and prepuce
- Venereal transmission through coitus or artificial insemination
- Nasal-genital transmission between cows has been postulated
- Lifelong latent infection with periodic virus shedding
- Sciatic ganglia are sites of latency in genital disease
- Recrudescence can be caused by stress (transport, parturition, etc.), corticosteroid administration, or superinfection by a new strain
TYPICAL CLINICAL FINDINGS:
- Painful urination, swelling and purulent preputial discharge with paraphimosis
- Reluctance or refusal to breed
TYPICAL GROSS FINDINGS:
- Early: Hyperemia and swelling of the penis and prepuce
- Later (2-3 d): Pustules > 1-2 mm ulcers > small gray foci of necrosis of the penile epithelium
- Lesions concentrated on the glans penis and prepuce
- Edema of penis and prepuce in severe cases
TYPICAL LIGHT MICROSCOPIC FINDINGS:
- Epithelial necrosis with neutrophilic accumulation
- Lymphocyte infiltration of the surrounding stroma
- Transient appearance of intranuclear viral inclusion bodies in degenerating epithelial cells
ADDITIONAL DIAGNOSTIC TESTS:
- Isolation or detection of virus through PCR or culture
- Serology with serum neutralizing titer
- For balanoposthitis in bulls:
- Granular venereal disease (bovine granular vulvovaginitis): Mycoplasma bovigenitalium
- Ulcerative posthitis: Corynebacterium renale is the suspected etiology
- Strongyloides papillosus
- Traumatic injury secondarily infected with bacteria, eg. Actinomyces pyogenes, E. coli, Streptococcus sp., and Staphylococcus sp.
- Infectious causes of balanoposthitis:
- Canine: Canine herpesvirus causes inflammation at the base of the penis and the reflection of the prepuce but does not cause pustules or ulcers
- Equine: Equine herpesvirus-3 (equine coital exanthema): Ulcers have a predilection for the body rather than the glans of the penis
- Sheep & Goats: Can be infected by BoHV-1, but usually develop an upper respiratory infection, not balanoposthitis
- Goats: Caprine herpesvirus-1: Ulcerative balanoposthitis with acidophilic intranuclear viral inclusions; may progress to extensive suppurative and necrotizing balanoposthitis involving the glans, fornix, and entire urethral process; abortion in females with neutrophilic infiltrates in kidneys, brain, liver, adrenal glands, and lungs of aborted fetuses with intranuclear viral inclusion bodies in cells within/around the necrotic foci in kidneys and adrenal glands
- Beluga whale: A papilloma-like penile lesion associated with beluga whale herpesvirus (BWHV) has been described
- Bellehumeur C, Lair S, Romero CH, Provost C, Nielsen O and Gagnon CA. Identification of a novel herpesvirus associated with a penile proliferative lesion in a beluga (Delphinapterus leucas). J Wildl Dis. 2015;51(1):244-249
- Foster RA. Male genital system. In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 3. 6th St. Louis, MO: Elsevier; 2016:506-507.
- Laguardia-Nascimento M, Sales EB, et al. Detection of multiple viral infections in cattle and buffalo with suspected vesicular disease in Brazil. J Vet Diagn Invest. 2016;28(4):377-381.
- Schalfer DH, Foster RA. Female genital system. In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 3. 6th ed. St. Louis, MO: Elsevier; 2016:433-434.