Treponema spp. spirochetes and keratinopathogenic fungi isolated from keratomas in donkeys.

Keratoma is an aberrant keratin mass thought to originate from epidermal horn-producing cells interposed between the stratum medium of the hoof wall and the underlying third phalanx. The cause is unknown, although the presence of keratomas is frequently associated with chronic irritation, focal infection, or trauma. A total of 167 donkeys with keratomas were presented in this study. The diagnosis of a keratoma was based on clinical signs, radiography, and histopathologic examination. Surgical excision was attempted on all donkeys with lameness unless euthanasia was advised. Histopathologic examination, including Giemsa, periodic acid Schiff, and Young's silver special histochemical stains, was performed and showed the presence of fungal hyphae and spirochete bacteria within the degenerate keratin. Polymerase chain reaction (PCR) for treponeme bacteria was performed on 10 keratoma lesions and 9 healthy pieces of hoof (controls). All healthy donkey tissues were negative for the 3 recognized digital dermatitis (DD) treponeme phylogroups, whereas 3 of 10 (30%) donkey keratoma samples were positive for one of the DD treponeme phylogroups. Routine fungal culture and PCR for fungi were performed on 8 keratoma lesions and 8 healthy pieces of hoof (controls). Keratinopathogenic fungi were detected in 1 of 8 (12.5%) keratomas, while only non-keratinopathogenic, environmental fungi were detected in 8 control healthy hoof samples. This is the first time the DD treponemes phylogroup and keratinopathogenic fungi have been detected in keratomas. Further studies are required to assess the significance of this finding.

A case of metabolic epidermal necrosis in a cat.

Abstract This report describes clinical, histological and post-mortem findings in a cat, that are similar to necrolytic migratory erythema in humans and to metabolic epidermal necrosis in dogs. Resumen Este articulo describe los hallazgos clinicos, histopatológicos y post mortem en un gato, similares a Eritema Necrolitico Migratorio en la especie humana y a Necrosis Epidérmica Metabólica en el perro. [Patel, A., Whitbread, J., McNeil. P. A case of metabolic epidermal necrosis in a cat. (Un caso de necrosis epidérmica en un gato.) Veterinary Dermatology 1996; 7: 221-226.] Résumé Ce cas décrit les lésions cliniques, histopathologiques et nécropsiques chez un chat, évoquant l'érythème nécrolytique migrant de l'homme et la nécrose épidermique métabolique du chien. [Patel, A., Whitbread, J., McNeil. P. A case of metabolic epidermal necrosis in a cat. (Un cas de nécrose épidermique métabolique chez un chat.) Veterinary Dermatology 1996; 7: 221-226.] Zusammenfassung Dieser Bericht beschreibt klinische, histopathologische und Sektionsbefunde bei einer Katze, die dem hekrolytischen migratorischen Erythem beim Menschen und der stoffwechselbedingten epidermalen Nekrose beim Hund ähneln. [Patel, A., Whitbread, J., McNeil. P. A case of metabolic epidermal necrosis in a cat. (Ein Fall von stoffwechselbedingter epidermaler nekrose bei der Katze) Veterinary Dermatology 1996; 7: 221-226.].

Epidermotropic Cutaneous T-Cell Lymphoma (mycosis fungoides) in Syrian Hamsters (Mesocricetus auratus). A Report of Six Cases and the Demonstration of T-Cell Specificity.

Abstract- Epidermotropic cutaneous T-cell lymphoma was diagnosed in six Syrian hamsters (Mesocricetus auratus) with a generalised dermatosis characterised by pruritus, alopecia and exfoliative erythroderma. Plaques and nodules were evident in one animal. Clinical and histopathological findings were suggestive of mycosis fungoides and electron microscopical investigations in one case were supportive. Immuno-histochemical stains for CD3 antigen were strongly positive in all cases. Résumé- Un lyphome T cutané a été diagnostiqué chez six hamsters de Sibérie (Mesocricetus auratus) avec une dermatose généralisée, caractérisée par un prurit, une alopécle et une érythrodermie exfoliative. Des plaques et des nodules ont été observées sur un animal. Les données cliniques et histopathologiques étaient évocatrices d'un mycosis fungoïdes et les examens en microscopie électronique étaient compatibles dans un cas. Les marquages immuno-histochimiques de l'antigène CD3 étaient très positifs dans tous les cas. Zusammenfassung- Bei sechs Syrischen Goldhamstern (Mesocricetus auratus) wurde ein epidermotropes kutanes T-Zell-Lymphom mit einer generalisierten Dermatose diagnostiziert, die durch Pruritus, Alopezie und eine exfoliative Erythrodermie gekennzeichnet war. Bei einem Tier traten auch Plagues und Knoten auf. Die klinischen und histopathologischen Befunde deuteten auf Mycosis fungoides hin. Elektronenmikroskopische Untersuchungen unterstützten diesen Verdacht in einem Fall. Immunhistochemische Färbungen auf CD3-Antigen waren bei alien Fallen stark positiv. Resumen En un grupo de seis hamsters de siria, (Mesocricetus auratus), se diagnosticó limfoma epidermotrópico cutáneo de linfocitos T, presentando una dermatosis generalizada de tipo pruriginoso, acompañada de alopecia y eritroderma exfoliativo. Las placas y nódulos fueron evidentes en uno de los animales. Los estudios clinicos e histopatológicos indicaron una micosis fungoide, y las investigaciones de microscopía, en uno de los caseos, pareció indicar lo mismo. La tintura inmuno-histoquimica para el antígeno CD3 resultó claramente positiva en todod los casos.

A dermal melanoma in a young common seal (Phoca vitulina).

A subcutaneous melanocytic tumor was diagnosed during the rehabilitation period of a stranded 7-mo-old common seal (Phoca vitulina) suffering from parasitic bronchopneumonia. The clinical signs of the seal as well as the histopathology of the tumor are described. This is the first time a melanocytic tumor has been diagnosed in a common seal. The mass was identified as a low-grade dermal melanoma.

A case of fatal systemic toxoplasmosis in a cat being treated with cyclosporin A for feline atopy.

Acute systemic toxoplasmosis was diagnosed in a 4-5-year-old, male, Domestic Short Hair cat, which had been on cyclosporine A immunomodulatory therapy for feline atopy, over an 8-month period. Cyclosporin A (CsA) has shown promising results as a immunosuppressive agent in the cat for the treatment of eosinophilic plaque and granulomas, allergic cervico-facial pruritus, feline atopy and other immune-mediated dermatoses. However, inhibition of T-lymphocyte function by CsA is believed to have predisposed this cat to the development of a newly acquired, acute Toxoplasma gondii infection, as characterized by severe hepatic and pancreatic pathology in conjunction with the heavy parasite load demonstrated on immunohistochemical (IHC) stains for T. gondii. Cats on CsA therapy appear to be at risk of developing fatal systemic toxoplasmosis.