A case of intestinal mucormycosis in a common marmoset (Callithrix jacchus)

A 3-year-old female common marmoset was euthanatized because of wasting. Grossly, a perforating lesion was present in the jejunum and hemorrhagic lesions in the cecum and colon. Histopathologically, these gross lesions were a perforated jejunal ulcer and necrotizing colitis, respectively. Necrotizing colitis was characterized by extensive mucosal necrosis along with numerous ribbon-shaped aseptate hyphae. These aseptate hyaline hyphae were positively stained with PAS and GMS, and reacted immunohistochemically with the antibody against the family Mucoraceae. This case was diagnosed as intestinal mucormycosis. This is the first report on mucormycosis in a common marmoset.     

Zygomycotic proventriculitis and ventriculitis in ostriches (Struthio camelus) with impaction

Three young ostriches (Struthio camelus), aged 4 months, were found to have zygomycotic proventriculitis and ventriculitis associated with impaction. Clinical signs were anorexia, chronic weight loss, weakness and lethargy followed by scant faeces for seven days. Proventriculi and ventriculi from birds were full of masses of hay, grass, leaves and other fibrous materials in combination with sand, gravel and plastic. Erosions and haemorrhagic ulcers of varying number and severity were present in the mucosae of both organs involved. Mucosal lesions were characterized by haemorrhagic necrosis. Throughout the affected mucosae there were 5 to 12 microns wide rarely-septated fungal hyphae with non-parallel walls, irregular branching and occasional globoid distentions, typical of Zygomycetes. Zygomycotic proventriculitis and ventriculitis secondary to impaction was diagnosed.     

Systemic mucormycosis in a hooded seal (Cystophora cristata)

A 4-yr-old male captive hooded seal (Cystophora cristata), previously diagnosed as hypothyroid, died after a 3-wk period of lethargy and inappetance despite treatment that included intramuscular administration of antibiotics and multivitamins. Gross pathologic findings included extensive muscle necrosis over the left flank, an underlying necrotic iliac lymph node, two necrotic pulmonary masses and a necrotic bronchial lymph node. Routine cultures yielded a number of bacterial isolates and a heavy pure fungal growth from the necrotic iliac lymph node; wet preparations of which revealed sporangiophores typical of Mucor sp. Histopathology of necrotic muscle, pulmonary lesions and bronchial and iliac lymph nodes revealed necrosis with a marked pyogranulomatous and eosinophilic inflammatory cell infiltrate and fungal hyphae consistent with a Zygomycete species. This is believed to be the first report of systemic mucormycosis in a pinniped likely to have originated from an injection site reaction.     

Eumycetoma in a British cat

A case of feline eumycetoma is described. The lesions principally affected the soft tissues of the right hip and right sublumbar region and were characterized by granulomatous swelling with sinuses, discharging pus containing black granules. The latter consisted of aggregations of fungal hyphae which on culture were identified as belonging to the genus Torula. The cat died before treatment could be instigated. Previous reports of eumycetoma in animals are reviewed.     

Variations in the morphology of Rhizomucor pusillus in granulomatous lesions of a Magellanic penguin (Spheniscus magellanicus)

This report presents a new case of mucormycosis encountered in penguin characterized by morphological variation of hyphae and presence of sporangia with numerous sporangiospores. A 4.5-year-old Magellanic penguin (Spheniscus magellanicus) died after exhibiting anorexia, poor nutritional condition and dyspnea. Multiple nodular lesions were observed in the thoracic and abdominal regions. Histopathologically, hyphae of various sizes were seen in the lungs, air sac and nodular lesions. Myriad sporangiospores and several sporangia were observed in/around the bronchi or parabronchi. The very narrow and short hyphae in the nodules were not consistent with the characteristics of Mucorales. However, for most hyphae, including those in the nodules, sporangiospores and sporangia, immunohistochemistry revealed Mucorales-positive reactions. In addition, these fungi were identified as Rhizomucor pusillus by gene analysis.     

Pulmonary aspergillosis in a horse with myelomonocytic leukemia

Acute myelomonocytic leukemia was diagnosed in a 2-year-old Standardbred mare that had hind limb edema and fever unresponsive to antibiotics. The mare had anemia, thrombocytopenia, and leukocytosis, with circulating myeloblasts and monocytoid cells. A bone marrow specimen was hypercellular, with myeloblasts and monocytoid cells. Peroxidase, chloroacetate esterase, and alpha naphthyl acetate esterase activities were detected in many bone marrow cells. Interstitial pulmonary densities were seen radiographically. The mare was euthanatized and necropsied. Infiltrates of leukemic cells were found microscopically in specimens of spleen, lymph nodes, liver, kidneys, gastrointestinal tract, and lungs. Granulomas containing fungal hyphae were seen microscopically in the lungs, and Aspergillus sp was isolated from the lesions.     

Presumptive organophosphate-induced delayed neurotoxicity in a paralyzed bull

A case of presumptive organophosphate-induced delayed neurotoxicity in a bull is described. All signs were referable to a focal cervical or diffuse spinal cord lesion. These included recumbency with severe symmetrical paresis of all 4 limbs, the hind limb involvement being greater than the forelimbs. CSF analysis was normal. The bull was killed and necropsied. There were no gross CNS lesions. Histopathologic finds are characterized and their resemblance to lesions observed in delayed neurotoxicity caused by organophosphate compounds is discussed. The bull had been treated with organophosphate insecticide (famphur) 43 days prior to the onset of signs.     

Suspected ergotism in two heifers

A syndrome similar to gangrenous ergotism was seen in 2 Friesian heifers grazing meadow hay containing perennial rye grass seed heads parasited by an ergot presumed to be Claviceps purpurea. Clinical signs were bilateral hind limb lameness and gangrene. There was angiographic evidence of vasoconstriction in the lower hind limbs with necrosis of all tissues in the distal region of both hind limbs.     

Fatal mycotic dermatitis in captive brown tree snakes (Boiga irregularis).

Cutaneous fungal infections occurred in four captive brown tree snakes (Boiga irregularis). The ventral scales were most commonly affected, and lesions began as areas of erythema and edema with vesicle formation, followed by development of caseous brown plaques. Lesions usually started where ventral scales overlapped and spread rapidly. All snakes died within 14 days after clinical signs were first noted. The deaths of three of the snakes were directly attributable to the cutaneous disease; the other snake died from renal failure and visceral gout, most likely induced by gentamicin therapy. Histologically, lesions consisted of epidermal hyperplasia and hyperkeratosis, with foci of epidermal necrosis, intraepidermal vesicle formation, and subacute inflammation of the underlying dermis. These lesions were associated with bacteria and numerous septate, branched fungal hyphae within the epidermis and overlying serocelluar crusts. Hyphae that penetrated through the superficial surface of the epidermis often formed terminal arthroconidia. The same species of fungus was isolated in pure culture from the skin of three snakes, but fungal cultures were not performed on samples from the fourth snake. The fungus has been identified as the Chrysosporium anamorph of Nannizziopsis vriesii based on its formation of solitary dermatophytelike aleurioconidia and alternate and fission arthroconidia. The source of the fungus in this outbreak was not determined; however, the warm, moist conditions under which the snakes were housed likely predisposed them to opportunistic cutaneous fungal infections.     

Outbreaks of pythiosis in two flocks of sheep in northeastern Brazil

Two outbreaks of cutaneous pythiosis caused by Pythium insidiosum were diagnosed in two herds of crossbred hair wool sheep of different ages in the semiarid region of Northeastern Brazil. In one herd of 120 sheep, 40 were affected. The other outbreak affected six sheep out of 80. Local swellings with ulcerative lesions were observed in the limbs and abdominal and prescapular regions. Three sheep were necropsied. Two of them had lung metastasis characterized by multifocal nodules measuring 0.5-2 cm. In one animal, the prescapular lymph node was also affected. In another, the cutaneous lesion extended to the sesamoid bone. Microscopically, there were multifocal granulomas with intralesional P. insidiosum hyphae and Splendore-Hoeppli material surrounding the hyphae. The diagnosis was based on the histologic lesions, immunohistochemical identification, and culture of the etiologic agent. One sheep treated with potassium iodide recovered. Standing in swampy water for long periods in a warm aquatic environment seems to be the reason for the high prevalence of the disease.     

Mycotic lymphadenitis in cattle and Swine

Lymph nodes with granulomatous mycotic lesions from 100 cattle and 9 pigs were examined. More than 90% of cases of mycotic lymphadenitis in cattle occurred in the mesenteric nodes, whereas in swine lesions occurred at multiple sites. All observed mycotic infections were caused by zygomycetes. Histologically the granulomas were characterized by necrosis, mineralization, and fibrosis with infiltration of eosinophils, neutrophils, lymphocytes, and giant cells. Mucoraceous-type hyphae were identified in most of the lesions, and Absidia corymbifera, Rhizopus rhizopodiformis, and R. oryzae were isolated. Within the lesions, chlamydospores were produced by R. rhizopodiformis. Mycelia in a few lesions were suggestive of infections with fungi of the Mortierellaceae and Entomophthoraceae.     

Corneal stromal abscess in a horse

A thoroughbred yearling presented with a focal, yellow, midstromal corneal opacity with concurrent iridocyclitis which was consistent with a corneal stromal abscess. When continued, appropriate, medical therapy failed to improve the patient's condition, penetrating keratoplasty was performed for diagnosis and therapy. Histopathology showed that the deep corneal stroma and Descemet's membrane were severely infiltrated with necrotic neutrophils and numerous, intralesional fungal hyphae. Culture was negative. Bacteria were not isolated, consistent with a fungal corneal stromal abscess. The resultant corneal scar did not interfere with the horse's racing career.     

Gross and microscopic lesions of polioencephalomalacia in a llama (Lama glama).

A 14-wk-old female llama (Lama glama) developed progressive neurologic disease characterized by stiff gait, circling, decreased mentation, and seizures. At necropsy, lesions were limited to the brain and consisted of bilateral necrosis of the cortical gray matter of the occipital lobes of the cerebral cortex. The primary microscopic alteration was bilateral laminar cerebrocortical necrosis, affecting mainly the deep laminae. Clinical disease, and gross and microscopic lesions were consistent with those of polioencephalomalacia.     

Necrosis and sloughing of skin associated with limb cellulitis in four cows and a calf: predisposing causes, treatment and prognosis

Four cows and a calf with non-suppurative limb cellulitis were observed subsequently to suffer skin necrosis and sloughing in the affected limbs, either on or distal to the metacarpus or metatarsus. In comparison with six cows with suppurative Corynebacterium pyogenes limb cellulitis, topical therapy or the cases with skin necrosis and sloughing was adequate and the prognosis was good, when compared with the rigorous systemic therapy applied to the cows with suppurative cellulitis, some of which died. The skin necrosis and sloughing resulting from limb cellulitis seemed to be encouraged by the paucity of tissue between the skin and the bone, by the poor vascularity of the area, and by the causative bacteria.     

MRI FINDINGS IN 232 HORSES WITH LAMENESS LOCALIZED TO THE METACARPO(TARSO)PHALANGEAL REGION AND WITHOUT A RADIOGRAPHIC DIAGNOSIS

Two hundred and thirty‐two horses with lameness localized to the metacarpo(tarso)phalangeal (MCP/MTP) region without a radiographic diagnosis were evaluated. All horses had high‐field magnetic resonance (MR) imaging of the MCP/MTP region performed for the lame limb and the contralateral limb for comparison. There were 46 horses that had bilateral abnormalities in the forelimbs; 27 of these horses were not lame in the contralateral limb at the time of examination. Bilateral hind limb abnormalities were observed in 37 horses; 22 horses were not lame in the contralateral limb. Soft tissue abnormalities alone were observed in 218 limbs (162 horses). Subchondral bone and articular cartilage abnormalities alone were observed in 43 limbs (34 horses). A combination of soft tissue, subchondral bone, and cartilage abnormalities were observed in 64 limbs (36 horses). The distribution of primary abnormalities was as follows; oblique distal sesamoidean ligament desmitis (73 limbs in 56 horses), straight distal sesamoidean ligament desmitis (44 limbs in 38 horses), chronic subchondral bone injuries (15 limbs in 12 horses), suspensory ligament branch desmitis (14 limbs in 12 horses), collateral ligament desmitis (12 limbs in 12 horses), tendonitis of the superficial and deep digital flexor tendons (10 limbs in 10 horses), osteochondral defects greater than 1 cm (nine limbs in six horses), osteochondral defects less than 1 cm (eight limbs in seven horses), bone marrow lesions (six limbs in five horses), intersesamoidean ligament desmitis (five limbs in four horses). MR imaging is useful in diagnosing bone and soft tissue injuries when radiographs and ultrasound fail to yield a diagnosis.     

Dermatophytosis in show lambs in the United States

A dermatophytosis, called 'club lamb fungus' by owners, has been affecting show lambs during the lamb show season. Thirty-one families of 108 responding to a questionnaire reported at least one case of dermatophytosis, and 15 of those 31 families reported children or owners involved in showing these lambs developing skin lesions consistent with dermatophytosis. In lambs, gross lesions typical of ovine derma-tophytosis were located on all parts of the body, and consisted of circular areas of matted wool, crusts and discoloration. Lesions appeared either at a single site or were distributed randomly, affecting head, body and extremities. Direct microscopic examination of wool revealed ectothrix, endothrix, and combined endothrix and ectothrix infections. Microsporum gypseum was the only dermatophyte cultured from wool samples collected from affected lambs; however, the presence of endothrix spores suggests that other species may be involved. Arthrospores and fungal hyphae typical of dermatophytes were present in histological sections.     

Diagnosis of canine nasal aspergillosis by cytological examination: a comparison of four different collection techniques

OBJECTIVES: To compare the efficacy and diagnostic value of four different sample collection techniques for cytological identification of nasal aspergillosis-penicilliosis in dogs. METHODS: Fifteen dogs with a history of persistent nasal discharge and clinical and radiographic findings suggestive of aspergillosis were evaluated using four different cytological sampling techniques. These were a direct smear from the nasal discharge, blind swab collection under general anaesthesia, brushing from suspect lesions under direct endoscopic visualisation and a squash technique of mucosal biopsies from suspect lesions obtained under direct endoscopic visualisation. RESULTS: Direct smear collection and blind swab collection detected fungal hyphae in 13.3 and 20 per cent of examined cases, respectively; brush samples detected fungal hyphae in 93.3 per cent and fungal spores in the 45 per cent of examined cases and squash samples detected fungal hyphae in 100 per cent and fungal spores in 36 per cent of examined cases. CLINICAL SIGNIFICANCE: This study confirmed the high accuracy of cytology samples in the diagnosis of nasal aspergillosis-penicilliosis when collected under direct endoscopic visualisation and showed the poor value of samples that were collected by blind swabs or prepared from samples of nasal discharge.     

Polioencephalomalacia in a llama

A 5-year-old, female llama (Lama glama) developed acute, progressive neurological disease, characterized by recumbency, muscle fasciculations, intermittent convulsions/opisthotonos, and absent menace responses. Postmortem histopathologic lesions, limited to the cerebral cortex, consisted of necrosis of the superficial and deep laminae. The clinical disease and microscopic lesions were consistent with polioencephalomalacia.     

Cutaneous Alternaria infectoria infection in a dog in association with therapeutic immunosuppression for the management of immune‐mediated haemolytic anaemia

A 4‐year‐old, ovariohysterectomized, English springer spaniel on immunosuppressive therapy was re‐examined for the review of its immune‐mediated haemolytic anaemia and the recent development of skin lesions. For the 3 months since hospital discharge, the dog had been receiving 1.3 mg/kg prednisolone and 2.6 mg/kg ciclosporin, both administered orally twice daily. Physical examination revealed hepatomegaly and multiple, purulent, crusting, erosive to ulcerative lesions over different body areas. Onychorrhexis had occurred on one digit and the underlying corium had blackened. There were two proliferative and one plaque‐like lesions in the mouth. Thick walled fungal hyphae were detected in impression smears from all skin lesions and staining with periodic acid–Schiff’s stain confirmed the presence of multiple fungal hyphae and spores in all biopsies examined. Fungal culture isolated a heavy, pure growth of an Alternaria sp. which was identified as A. infectoria by sequencing the internal transcribed spacer 1 region of the rRNA gene. The animal’s condition prevented detailed investigation of the oral lesions. Withdrawal of the ciclosporin and reduction of the prednisolone dosage resulted in spontaneous resolution of the skin lesions within 40 days. Further gradual decrements in the prednisolone dosage to zero were carried out without recurrence of the immune‐mediated haemolytic anaemia. After 12 months, there has been no recurrence of either the skin lesions or the anaemia. To the authors’ knowledge, this is the first reported case of A. infectoria infection in a dog.     

Disseminated acute concomitant aspergillosis and mucormycosis in a pony

A 6-year-old female pony died after 2 days of prostration. Clinical signs included hyperthermia and abnormal pulmonary auscultation sounds. Necropsy revealed diffuse severe necrohaemorrhagic colitis and splenitis, multiple visceral ecchymoses, petechial haemorrhages in the brain and lungs. Microscopical examination showed acute necrohaemorrhagic colitis, encephalitis, pneumonia and splenitis associated with fibrinoid vasculitis, thrombosis and fungal hyphae within and around vessels. Immunohistologically, concomitant aspergillosis (caused by Aspergillus fumigatus) and mucormycosis (causde by Absidia corymbifera) were identified in the colonic and pulmonary lesions, whereas pure mucormycosis was observed in cerebral and splenic lesions. Dual mycotic infections are very rarely described, and the present case emphasizes the need of immunohistochemistry in order to obtain a clear-cut diagnosis of mixed fungal infections.