Pyogenic granuloma of the cornea in a pony: Uncommon complication of corneal wound healing.

A 6-year-old miniature Shetland pony mare was referred for evaluation of a left corneal mass, which developed from the healing tissue of a corneal traumatic ulceration that had occurred 4 weeks previously. On gross examination, a spherical, smooth-surfaced, and pink-colored lesion of about 1 cm in diameter was protruding from the left palpebral fissure. Ophthalmic examination revealed that it was attached to the scar tissue of the cornea, and that one corpora nigra was adherent to the posterior face of corneal wounded area, without sign of uveitis. The remainder of the ophthalmic examination was unremarkable. The mass was excised, and cryotherapy was used as an adjunctive therapy. Histopathology of the resected mass was consistent with a pyogenic granuloma on the basis of radially oriented proliferating capillaries, embedded in immature granulation tissue containing an infiltrate of neutrophils, plasma cells and eosinophils. There were no histological features of malignancy. 2 months after surgery, the ventral part of the fibrotic corneal scar was slightly raised by a pink tissue, suggesting possible recurrence of the initial lesion. A second cryotherapy was performed over the leukoma area. No recurrence has been noted for a follow-up period of more than 25 months. Pyogenic granuloma is a benign proliferative fibrovascular response that typically develops after trauma or surgery. Corneal involvement is rare in humans, and to the authors' knowledge has never been documented in veterinary ophthalmology.

Granulation tissue-type hemangioma in a 6-week-old puppy - a case report.

BACKGROUND: Hemangioma is a well-known neoplasia in veterinary and human medicine. Several subtypes have been described and are distinguished based on their histologic appearance. The classification schemes of hemangiomas in human and veterinary medicine are different, and various purpose-based schemes can be found in the literature. CASE PRESENTATION: A six-week-old puppy was presented that suffered from a neoplasia that extended to the musculature of the hind limb. After surgical excision, the mass was submitted for pathohistological examination. The mass was composed of endothelial cells forming vascular slits admixed with a fibrous stroma and spindle cells. Immunohistological examination was positive for factor VIII-related antigen and smooth muscle actin, supporting the diagnosis of hemangioma. CONCLUSION: The final diagnosis of granulation tissue-type hemangioma was given due to the histological appearance of the neoplasia. Granulation tissue-type hemangioma is a rare subtype of hemangioma. In this case an uncommonly young dog was affected.

Clinicopathologic characterization of oral pyogenic granuloma in 8 cats.

This case series characterizes the clinicopathologic features and treatment of oral pyogenic granuloma in 8 cats. The cats reported here were patients originating from collaborative efforts at an academic clinical teaching hospital and a specialty dentistry/oral surgery referral practice. Although the initial biopsy results were variable, in all cases the diagnosis reflected an inflammatory process. A second clinicopathologic evaluation of these cases determined that all lesions were consistent with oral pyogenic granuloma. The location of the lesion was consistent among all cats within the present study Lesions developed at the vestibular mucogingival tissues of the mandibular first molar teeth. We propose that malocclusion and secondary traumatic contact of the ipsilateral maxillary fourth premolar tooth with the mandibular soft tissues is a possible contributing factor in the etiopathogenic mechanism.

Pyogranulomatous skin disease and cellulitis in a cat caused by Rhodococcus equi.

This report describes a case of Rhodococcus equi infection causing pyogranulomatous skin disease and cellulitis in a two-year-old female domestic shorthaired cat. The case differed from previously reported cases in cats in its clinical presentation and in the locations of the lesions, which were similar to those seen in horses. The presence of an intracellular organism was confirmed by cytology and on histopathology. The aetiological diagnosis was confirmed by routine biochemical tests specific for R. equi on a pure isolate obtained from a biopsy specimen. The report also reviews the literature of the documented feline cases and discusses the common pitfalls in the diagnosis of such infections.

Epulides in the dog: a review.

This article is based on a review of the literature and the study of pathology sections obtained from various veterinary pathology laboratories. Epulis is a non-specific, clinical designation for a localized, exophytic growth on the gingiva. Four reactive epulides occur in human beings, namely focal fibrous hyperplasia (fibrous epulis), pyogenic granuloma, peripheral giant cell granuloma (giant cell epulis), and peripheral ossifying fibroma (calcifying fibrous epulis). The first three also occur in dogs but only focal fibrous hyperplasia appears to be common. The peripheral ossifying fibroma has not yet been reported in dogs. Odontogenic tumors occurring on the gingiva (i.e., as epulides) are referred to as peripheral odontogenic tumors. Three types have been reported in dogs. One, the common fibromatous epulis, is equivalent to the rare peripheral odontogenic fibroma in human beings. Another, the acanthomatous epulis, appears to be a form of ameloblastoma but differs from the peripheral ameloblastoma in human beings in that it invades bone; its biological behavior is therefore that of the human intraosseous ameloblastoma. The third, a rare lesion, has been referred to in the veterinary literature as a calcifying epithelial odontogenic tumor, although it is not the canine counterpart of the human CEOT. The term, amyloid-producing odontogenic tumor, has been suggested as being appropriate for this lesion.

Cellular composition of Corynebacterium pseudotuberculosis pyogranulomas in sheep.

The cellular composition of 46 pyogranulomas experimentally induced with Corynebacterium pseudotuberculosis in sheep was determined by immunohistochemistry. Lesions localized in inoculation sites or draining lymph nodes consisted of macrophage and lymphocyte layers distributed around a necrotic center and surrounded by a fibrous capsule. In immature lesions, T cells of the CD4+ subset predominated, whereas in mature lesions proportions of CD8+ T lymphocytes and cells expressing the gamma/delta chains for the T cell receptor increased. Numerous pyogranuloma cells expressed the interleukin-2 receptor. In addition to these general characteristics, a large individual variability in the proportions of macrophage and T cell subsets was observed for lesions of the same age, in particular for epithelioid macrophages. This heterogeneity suggests a different cellular pattern in relation to the persistence or the elimination of bacteria by the host.