Gastric granulomatous cryptococcosis mimicking gastric carcinoma in a dog

Summary

An ulcerated lesion resembling a tumour in the lesser curvature of the stomach of a 3‐year‐old male Dobermann pinscher was found to be caused by Cryptococcus neoformans. The dog had been vomiting for two months and had slight leucocytosis and anaemia. Biopsies of the ulcerated lesion revealed granulomatous inflammation and many cryptococci, which were particularly prominent in PAS and mucicarmine stained sections. No other lesions were found at necropsy.     

Macrohematuria and life-threatening anemia attributable to subepithelial vascular ectasia of the urinary bladder in a dog

Hematuria leading to life-threatening anemia was evaluated in a 9-year-old male dog. At surgery, an abnormal vessel resembling an ulcerated varicose vein was found on the surface of the bladder mucosa. After removal of the lesion, hematuria ceased and had not recurred 22 months later.     

Two cases of feline leishmaniosis in Switzerland

Two cats with Leishmania species infections were investigated. The first had been imported from Spain with a non-healing, ulcerated nodule on a hindleg. The presence of Leishmania species was detected by histopathology and pcr on samples of skin. The lesion was unresponsive to treatment with allopurinol for three months but the cat was treated successfully by removing the lesion surgically. The second cat had lived in both Spain and Switzerland, and had a history of recurrent skin lesions on its head and neck. A diagnosis of pemphigus foliaceus was made on the basis of histopathology, but Leishmania species serology (elisa) and pcr of skin were positive, leading to a diagnosis of a Leishmania species infection combined with pemphigus foliaceus.     

Metastatic malignant melanoma in a prehensile-tailed porcupine (Coendou prehensilis)

A 14-yr-old male, prehensile-tailed porcupine (Coendou prehensilis) presented for an ulcerated, bleeding lesion of the right flank. The wound presented similar to a bite wound and was treated with antibiotics. After 2 mo, the lesion had increased in size and was nonhealing, so surgical excision was elected. Histopathology diagnosed this lesion as a malignant melanoma with incomplete margins. Radiographs showed no evidence of pulmonary metastasis. At 6 mo, another skin lesion was removed and was diagnosed as malignant melanoma with clean surgical margins. At 8 mo, another four dermal masses were surgically excised and, again, these were melanomas that were completely excised. The animal was euthanized approximately 15 mo after initial presentation due to continued growth of dermal masses, dyspnea, and decreased appetite. Necropsy and histopathology revealed metastatic melanoma present in skin, kidneys, and lung.     

Mycobacterium ulcerans infections in two horses in south-eastern Australia

Two horses were diagnosed as having Mycobacterium ulcerans infections. The first was a 21-year-old Quarterhorse-cross mare living in Mallacoota (a coastal town near the border of New South Wales and Victoria, Australia) that presented with lichenification, hair-loss and oedema on a fetlock, which subsequently ulcerated, as well as a non-healing ulcer on the wither. The second horse was a 32 year-old Standardbred gelding from Nicholson, near Bairnsdale, Victoria, that had an ulcerated lesion on its caudal thigh. Histologically, there were characteristic changes seen with M. ulcerans infections in other species, including extensive necrosis without associated granulomatous inflammation. The organisms were seen in Ziehl-Neelsen-stained smears or sections of the lesions from both horses and were isolated in culture from the first horse. A definitive diagnosis was provided by real-time polymerase chain reaction targeting the M. ulcerans-specific insertion sequence, IS2404. Delayed identification of the infectious agent in the first case led to the use of suboptimal antimicrobial therapy, resulting in failure to control the infection and the horse was subsequently euthanased. The second horse was successfully treated following surgical debulking of the centre of the lesion and one session of aggressive cryosurgery. Mycobacterium ulcerans should be considered in the differential diagnosis of unexplained lichenification with oedematous and ulcerated skin lesions in horses living in regions where this organism is endemic.     

Intracellular success: cytologic findings in an ulcerated submandibular mass from a cat

A 1-year-old neutered male domestic shorthair cat had an ulcerated, proliferative lesion in the submandibular area that did not respond to antibiotic therapy. Impression smears from the mass revealed septic pyogranulomatous inflammation, with large numbers of pleomorphic bacteria observed intracellularly within macrophages as well as neutrophils. Bacterial culture was consistent with a diagnosis of Rhodococcus equi, a facultative intracellular coccobacillus capable of replicating within macrophages. The cat's lesion resolved after treatment with rifampin and clarithromycin. R equi should be considered as a differential diagnosis when coccobacilli are recognized within macrophages in cytologic samples.     

Calcareous degeneration of the canine cornea

The purpose of this paper is to describe a specific presentation of canine corneal calcification. Fourteen cases are described. In seven cases the corneal lesions were bilaterally symmetrical. In five cases the corneal lesion was unilateral. Two dogs were uniocular, the contralateral eye had been enucleated between 1 and 3 months previously by the referring veterinary surgeon following corneal ulceration and perforation. Of a total of 21 eyes with corneal calcification, 16 eyes had associated ulceration. The ulceration presented as follows: two eyes had descemetocoeles, four eyes had corneal perforations, eight eyes had stromal ulceration, and two eyes had superficial punctate ulceration. The cause of the corneal mineralization remains undetermined but underlying systemic disease, particularly hyperadrenocorticism (Cushing’s Syndrome), is suspected as a possible contributing factor in some of these cases. Histopathology was carried out on three cases following a keratectomy and placement of a conjunctival pedicle flap into the ulcerated lesion.     

The prevalence and distribution of gastric ulceration in 345 racehorses

OBJECTIVE: To report the prevalence and distribution of gastric ulceration within a group of racehorses and to describe the endoscopic appearance of gastric antrum and pyloric ulceration. DESIGN: Retrospective clinical study. PROCEDURE: Medical records from gastroscopic examinations of 345 racehorses (331 Thoroughbreds and 14 Standardbreds) were reviewed. Prevalence, distribution and severity of gastric ulcers were recorded. Lesions involving the squamous mucosa and the glandular mucosa of the antrum and pylorus were graded and compared. RESULTS: Gastric ulceration was found in 86% of racehorses. The squamous mucosa around the margo plicatus was most commonly affected. The pylorus was examined in 175 horses and 47% were ulcerated. No association was found between presence of lesions of the squamous mucosa and those of the pylorus. Low correlation was found between grade and location of lesions, with the pyloric lesion score being significantly less than the squamous mucosal lesion score. CONCLUSION: Gastric ulceration was present in a large proportion of racehorses. The pylorus was also an important site of ulceration. There was no association between presence of lesion at one site and the other, although there was a low correlation between grade of lesion and location, with the pyloric ulcer grade being lower.     

Cutaneous mucormycosis caused by Absidia corymbifera in a horse

A 5-year-old pregnant Spanish thoroughbred mare was presented with an extensive granulomatous lesion, of four months duration, on the left medial foreleg. On examination, the wound was covered by a large mass of ulcerated granulation tissue exuding thick serosanguinous fluid. The mare had not responded to previous treatment. Physical examination revealed no fever, no lameness and the presence of intense pruritus. A surgical resection was carried out to take samples for histopathology. On histopathologic examination the dermis and subcutaneous tissue showed large multifocal necrotic eosinophilic areas and inside these areas, irregularly ramified fungal hyphae. Microbiological examination showed abundant fungal growth and the strain corresponded to Absidia corymbifera . Treatment with amphotericin B was started but there was no improvement in the lesion. The mare aborted, became anorexic, had febrile episodes, had very poor body condition and was euthanized.     

Presumptive subcutaneous surgical transplantation of a urinary bladder transitional cell carcinoma in a dog

A urinary bladder mass in a 12-year-old spayed female West Highland White Terrier was diagnosed after exploratory surgery and biopsy as a transitional cell carcinoma. Four months later the dog presented with an ulcerated plaque-like cutaneous lesion at the previous surgical incision site; concurrent inguinal lymphadenopathy and recurrence of the urinary bladder mass were identified. Transitional cell carcinoma was diagnosed at all 3 sites. Although a definitive relationship cannot be established between the initial surgery for urinary bladder mass and the resultant subcutaneous lesion, surgical implantation should be considered as a source for the neoplastic cells.     

Clinical Vignette

This 12-month-old, outdoor intact male cat (Fig. 1) was examined because of an untreated draining nasal lesion. The lesion. initially appeared as small punctures, and progressed ovcr 2 months to an ulcerated draining nodule that gradually enlarged to involve the whole muzzle, extending bilaterally to the medial canthi and having multiple drainage points through overlying necrotic skin. Results of serum feline leukemia virus antigen and feline immunodeficiency virus antibody tests were negative.     

Cyclosporin as the sole treatment for anal furunculosis: preliminary results

Cyclosporin was used, as the sole agent, to treat six cases of anal furunculosis, allowing the clinical response to the drug to be evaluated. The initial dose was 7.5 mg/kg twice a day. Following one week of treatment, whole blood cyclosporin trough levels were measured and the dose was adjusted to obtain a stable trough level of 400 to 600 ng/ml. In all dogs, the lesions were found to follow a similar pattern of resolution throughout the course of treatment. The presenting signs disappeared within one week of treatment, with a reduction in lesion size of 50 to 90 per cent. Lesions then gradually healed over the remainder of the treatment, which lasted from 10 to 20 weeks. One case required cryosurgical treatment to resolve a 2 mm diameter persistent ulcerated lesion following 18 weeks of treatment. The length of follow-up was four to 14 months (mean 7.7 months). One case developed recurrence of the lesions eight weeks post-treatment.     

Seminoma with cutaneous metastases in a dog

A 10-year-old Great Pyrenees was presented for anorexia and weight loss. On physical examination, the dog was emaciated and showed a large ulcerated lesion on the right lower lip in addition to an enlarged right testicle. Fine-needle aspiration biopsy of the testicle and surgical biopsy of the lip lesion were performed; the histopathological report was consistent with metastatic seminoma. The diagnostic and therapeutic approach in this unusual metastatic seminoma is presented and compared to the previous literature. A multimodality therapy consisting of surgery and chemotherapy is proposed for the clinical management of metastatic seminoma in dogs.     

Cutaneous vascular malformation in a guinea pig (Cavia porcellus)

Abstract   A skin lesion classified as a vascular malformation is reported in a young-adult, female guinea pig. The physical examination revealed a 3 × 2-cm irregularly shaped violaceous plaque located on the left caudal flank. The surface of the plaque was ulcerated and bled intermittently, resulting in fatal blood loss. On histology the mass consisted of variably sized vascular spaces filled with red blood cells and variable amounts of extramedullary haematopoietic cells, lined by well-differentiated endothelial cells often surrounded by one layer of spindle-shaped cells. Based on immunohistochemistry, the spindle cell population was confirmed to be smooth muscle cells and no proliferation of endothelial cells was found with the Ki67 proliferation marker. Histological and immunohistochemical findings were consistent with a vascular malformation. Classification of vascular malformations and potential treatments are discussed. To the authors' knowledge, this is the first reported case of a cutaneous vascular lesion in a guinea pig.     

Aetiology of food-related oral lesions in chickens

Brown Leghorn chickens fed on a mash diet developed ulcerated oral lesions with extensive epithelial erosion and large colonies of bacteria. Some birds had lesions by six weeks old and by 30 weeks oral lesions were present in all birds fed on a mash diet. These lesions occur infrequently in birds fed a pelleted diet and the relatively extensive lesions shown by birds on a mash diet heal quickly (in many cases within two weeks) when the birds are transferred to a pelleted diet. The cause of the lesion is unknown but there was no evidence for food impaction, mechanical damage to the epithelium, specific dietary constituents or blocked salivary ducts. The lesions may be due to poor oral hygiene which results from the lack of mechanical stimulation of the oral epithelium to which fine particles of mash adhere.     

Eosinophilic keratitis and keratoconjunctivitis in a 7-year-old domestic shorthaired cat

A 7-year-old, spayed female, domestic shorthair was presented with a several-month history of an ulcerated right cornea with marked stromal edema and inflammation that was nonresponsive to therapy. A diagnosis of eosinophilic keratitis was made, based on cytologic examination of corneal scrapings. The lesion resolved after treatment with topical corticosteroids.     

Osteosarcoma in a woma python (Aspidites ramsayi)

Osteosarcoma of the axial skeleton in an 18-month-old woma python (Aspidites ramsayi) is described. A subcutaneous mass overlying the costal arches enlarged progressively over a period of 5 months and, in that time, became ulcerated and more invasive of surrounding tissues. A punch biopsy of the lesion under general anaesthesia provided tissue for histopathology and diagnosis of low-grade osteosarcoma.     

Hypertrophic scar in a dog: histological and clinical features

An adult male bullmastiff dog was treated for paraparesis and ataxia due to discospondylitis and disc herniation. At this time, the dog had a nonhealing ulcer between the pads of the left hindfoot. At re-evaluation, the dog had developed a large exophitic mass in the previously ulcerated area. Cytological examination revealed occasional spindle cells with mild atypia, and a soft tissue tumour was suspected. The mass was excised and submitted for histology. The lesion was characterized by superficial ulceration, an intermediate layer of granulation tissue and a deep portion containing vertically orientated capillaries and perpendicularly arranged fibroblasts and collagen. The histological features led to a diagnosis of hypertrophic scar. Eight weeks after surgery, the lesion recurred and was treated with an intralesional injection of methylprednisolone acetate. The lesion regressed in 10 days, but recurred after 3 months following severe self-trauma. Hypertrophic scars and keloids are two types of exuberant scarring reported in human beings, the pathogenesis of which is still unclear but seems to involve several cytokines, growth factors and inflammatory cells. The histological features identified in this case paralleled those reported in hypertrophic scars in humans. In this case, intralesional corticosteroid therapy was useful in the management of the lesion, but the severe self-trauma could have influenced the recurrence. Even if uncommon, hypertrophic scar should be included among the differential diagnoses of spindle cell tumours in dogs.     

Squamous cell carcinoma in an American bison (Bison bison bison)

The following case report is, to the best of our knowledge, the first documentation of a squamous cell carcinoma in a full-blooded American bison (Bison bison bison). This female bison developed an ulcerated lesion on the left flank, at the site of a brand, in the summer of her eighth year. In the winter of her ninth year, as the lesion continued to grow, a biopsy was performed, and a diagnosis of squamous cell carcinoma was made. Ultimately, there was metastasis to the liver, a lung, and a prefemoral lymph node.     

Skin lesions caused by orthopoxvirus infection in a dog

A seven-year-old male dobermann was presented for examination of a non-pruritic ulcerated lesion occurring at the site of a suspected rat bite on the muzzle. Biopsy revealed focal ulcerative dermatitis, with cells in the epidermis, follicular infundibula and interposed sebaceous glands undergoing ballooning degeneration and containing large acidophilic intracytoplasmic structures resembling poxvirus inclusion bodies. The diagnosis of orthopoxvirus infection was confirmed by transmission electron microscopy and immunohistochemistry. The biopsy site healed uneventfully, without evidence of recurrence or development of further cutaneous or internal lesions, and a serum sample collected eight weeks after first presentation had a low titre of poxvirus antibodies. This report demonstrates that orthopoxvirus infection should be considered as a cause of ulcerative skin lesions in dogs, particularly if there has been recent contact with rodents or other small mammals.