Disseminated mycosis in layer cockerels and pullets

Eight-wk-old layer cockerels and pullets were presented to the diagnostic lab with a history of increased mortality, ruffled feathers, lameness, and recent vaccination. At necropsy, the birds had large multifocal granulomas in multiple tissues. Only light bacterial growth was seen on culture. On histopathology, a mixed population of fungi was seen within the granulomas including zygomycetes and Aspergillus, with the zygomycetes being the predominant organism. Because of the coinfection with Aspergillus and Penicillium, obtaining the zygomycetes in pure culture was unsuccessful. The source of the zygomycete fungi remains unknown; however, zygomycetes are known to be ubiquitous. Serology was performed to evaluate the flock's immune status. There was no evidence of immunosuppression caused by chicken anemia virus or bursal disease infections. No flock treatment was initiated.     

Disseminated mycobacteriosis in a cat (abstract)

A 12-year-old, FIV-positive domestic cat from rural Northland presented with diffuse and slowly progressive swellings of the vulva, tail base, head, and distal limbs. Fine needle aspirate biopsy of the subcutis revealed large numbers of pleomorphic acid fast bacteria. At necropsy, the dermis and subcutis in the affected areas were expanded by a pale yellow opaque infiltrate. Large ulcerated cutaneous swellings were present in the left maxillary area and bilaterally at the point of the jaw corresponding to the submandibular lymph nodes. Cutaneous nodules were present in the pre-auricular area. The skin of the carpi and tarsi was thickened and there was extensive hair loss, also evident over the tail base. The internal organs were normal in appearance. Histopathologically, the cutaneous swellings consisted of sheets of large foamy macrophages, macrophages, containing yellow/brown pigment and large numbers of acid-fast bacilli, that extended from the superficial dermis to the subcutis and fascia. Infiltrates of acid fast-laden macrophages were present in the liver, lung, spleen, and lymph nodes. Infection by a novel saprophytic Mycobacterium spp was considered most likely.     

Disseminated coccidoidomycosis in a koala (Phascolarctos cinereus)

A16-yr-old male koala (Phascolarctos cinereus) presented for nonspecific signs of illness and weight loss. Despite 2 mo of diagnostics and supportive care, the koala's health declined and euthanasia was elected. On histopathologic examination, lesions containing fungal organisms morphologically consistent with coccidioidomycosis were found in the lung, liver, spleen, kidney, lymph node, heart, eye, and bone marrow. Although disseminated infection was present, the koala was IgM and IgG seronegative for Coccidioides spp. 1 mo prior to euthanasia.     

Epitheliotropic cutaneous lymphoma (mycosis fungoides) in a dog

A seven-year-old castrated male Yorkshire terrier dog was presented for a recurrent skin disease. Erythematous skin during the first visit progressed from multiple plaques to patch lesions and exudative erosion in the oral mucosa membrane. Biopsy samples were taken from erythematous skin and were diagnosed with epitheliotropic T cell cutaneous lymphoma by histopathology and immunochemical stain. In serum chemistry, the dog had a hypercalcemia (15.7 mg/dl) and mild increased alkaline phosphatase (417 U/l). Immunohistochemistry was performed to detect parathyroid hormone-related peptide (PTH-rP) in epitheliotropic cutaneous lymphoma tissues but the neoplastic cells were not labeled with anti-PTH-rP antibodies. The patient was treated with prednisolone and isotretinoin. However, the dog died unexpectedly.     

Epitheliotropic cutaneous lymphoma (mycosis fungoides) in a coati

The aim of this report was to present a case of epitheliotropic cutaneous lymphoma (mycosis fungoides) in a coati. The animal was presented for evaluation of a non-pruritic nodule. Although the diagnosis of cutaneous histiocytoma was made histologically, plaques and erosions appeared in new areas of the skin along with rapid deterioration of body condition that led to euthanasia in less than one month following initial presentation. Epitheliotropic cutaneous lymphoma was confirmed with plaque biopsies. Cross-reactivity of a polyclonal antihuman CD3 antibody to coati T lymphocytes was also observed. Apart from skin lesions, only pleuritis was post-mortem diagnosed most likely because of immunosuppression secondarily to malignant neoplasia.     

Disseminated histoplasmosis in a Bengal tiger (Panthera tigris)

Disseminated infection with Histoplasma capsulatum was diagnosed in a 7-yr-old female Bengal tiger (Panthera tigris). Clinical signs were nonspecific with the exception of brief periods of tachypnea for 5 days prior to death. H. capsulatum organisms were found in the lungs, tracheobronchial lymph nodes, and liver. Diagnosis was confirmed by tracheal wash, urine H. capsulatum enzyme immunoassay, and necropsy results. This report represents the first published account of disseminated histoplasmosis in a tiger.     

Disseminated pheochromocytoma in a North American river otter (Lontra canadensis)

A 21-yr-old male North American river otter (Lontra canadensis) with a chronic history of degenerative osteoarthritis was evaluated for acute posterior paralysis. Because no definitive cause was identified and a poor prognosis was expected, the otter was euthanatized. A malignant neoplasm of adrenal gland origin with disseminated metastases to the central nervous system, lymph nodes, diaphragm, pancreas, spleen, and liver was diagnosed on postmortem examination. No clinical signs of disseminated neoplasia had been noted throughout the otter's history. The adrenal neoplasm was composed of nests of epithelial cells surrounded by a fine fibrovascular stroma. Neoplastic cells were immunohistochemically positive for chromogranin A, PGP9.5, metencephalin, and endorphin and negative for melan A and inhibin, confirming a diagnosis of a malignant pheochromocytoma. On the basis of the necropsy finding, metastasis of the pheochromocytoma might have contributed to the observed clinical signs.     

Disseminated Mycobacterium celatum (type 3) infection in a domestic ferret (Mustela putorius furo)

A 4-year-old male ferret (Mustela putoriusfuro) had a 6-month history of weight loss and gradual development of depression and coughing. Necropsy findings included pale gray tissue around the distal trachea, multiple nodules in the lungs, a single nodule in the stomach wall, gray foci in the liver, and enlarged lymph nodes. Histologic examination revealed multifocal to coalescing granulomatous inflammation in the trachea, lungs, stomach, liver, and lymph nodes, with acid-fast bacteria in epithelioid cells and macrophages. The acid-fast bacteria were identified as Mycobacterium celatum (type 3) using DNA sequence analysis of the 16S ribosomal DNA gene. M. celatum is a recently described mycobacterium isolated mainly from immunocompromised humans. This is the first report of M. celatum infection in an animal.     

Disseminated toxoplasmosis in black-footed penguins (Spheniscus demersus)

Three 1- to 3-mo-old black-footed penguins (Spheniscus Demersus) died within 24 hr of showing central nervous signs such as ataxia. The birds were housed in a baby penguin crèche. At necropsy, peritonitis, pneumonia, hepatomegaly, splenomegaly, and renomegaly were evident. Histologically, the liver, lung, brain, and small intestine contained numerous tachyzoites and a few cysts of Toxoplasma. Immunohistochemistry identified the protozoal parasites as Toxoplasma gondii. Ultrastructurally, this was confirmed by the presence of many tachyzoites of T. gondii in the liver and lungs.     

Disseminated panniculitis in a bottlenose dolphin (Tursiops truncatus) due to Mycobacterium chelonae infection

A 14-year-old female bottlenose dolphin was diagnosed with mycobacterial panniculitis based on punch biopsy specimens. The necropsy revealed numerous pyogranulomas in the blubber, as well as marked acute multifocal necrosuppurative pneumonia and lymphadenitis. In addition, the animal had marked scoliosis, which had first been noted clinically in the dolphin at about 1 mo of age. The animal had been treated with low-dose dexamethasone for approximately the last 19 mo to reduce perceived discomfort from spondyloarthritis and with the progestational agent altrogenest for approximately 8 yr to prevent pregnancy. Acid-fast positive bacilli were detected in the dermis but not in lung or lymph nodes. Mycobacterium chelonae was isolated from pooled skin, lung, and peripheral lymph-node tissue. Mycobacterial infection may be considered as a differential diagnosis in bottlenose dolphins with generalized cutaneous inflammation, particularly if chronic steroid and progesterone treatments were administered, both of which may have an immunomodulatory effect.     

Disseminated mite infection with ocular involvement in a juvenile bald eagle (Haliaeetus leucocephalus)

A bald eagle (Haliaeetus leucocephalus) was found unable to fly and was admitted to The Raptor Center (TRC). Major clinical signs were thin body condition and a cardiac arrhythmia. Ten days after admission to TRC, ophthalmic examination revealed multiple, distinct serpiginous lesions of chorioretinal atrophy in the ocular fundus of the right eye (OD). The bird was euthanized because of clinical deterioration and poor prognosis. Mites of an undetermined species were found histologically in the retina, episcleral tissues, lungs, and liver at the postmortem examination. Disseminated mite infection should be considered in the differential diagnosis of serpiginous chorioretinal lesions in bald eagles (H. leucocephalus).     

Systemic mycosis in a California sea lion (Zalophus californianus) with detection of cystofilobasidiales DNA

A 6-yr-old, intact male California sea lion (Zalophus californianus) with a systemic mycosis died after 5 wk of antifungal drug therapy. Antemortem clinical findings included hind flipper swelling, ring-lesions on skin of the flippers, and dermal nodules that increased in size and number spreading from the hind flippers and ventral abdomen to the foreflippers and muzzle. Lesions were accompanied by severe lymphadenopathy and development of systemic clinical signs despite therapy using itraconazole and later voriconazole. Histopathologic evaluation of biopsies revealed granulomatous dermatitis due to infection by fungus-producing yeast cells in tissue. Isolation attempts, using biopsied skin and tissue samples collected at necropsy, failed to yield growth of a fungus producing yeast cells like those in histologic section. Consensus polymerase chain reaction (PCR) tests of biopsied skin for fungal DNA produced an amplicon having significant sequence identity with a Cystofilobasidiales, a fungus belonging to a subclade that includes several Cryptococcus spp. Histopathologic evaluation of necropsy tissues revealed a systemic mycosis with yeast cells disseminated throughout subcutis, lymph nodes, and viscera. Hepatic necrosis was identified associated with acute liver failure, possibly from the voriconazole administration. This is the first report documenting the clinical presentation, treatment, and pathologic findings of infection associated with Cystofilobasidiales in a marine mammal and serves to expand the understanding of mycoses in pinnipeds.     

Disseminated intravascular coagulation (DIC) in rabbit haemorrhagic disease.

Seven rabbits experimentally infected with rabbit haemorrhagic disease virus were examined haematologically and histologically. Haematologically, activated partial thromboplastin time and prothrombin time were markedly prolonged in the terminal phase of the disease, just prior to death (all the animals died between 27 and 40 hr after inoculation with rabbit haemorrhagic disease virus). There was an increase in the titre of fibrin degradation products and a decrease in antithrombin III activity during the same interval. Acute necrotic hepatitis and disseminated intravascular coagulation (DIC) in many organs, including the lung, kidney, spleen and heart were the characteristic histopathological changes. Thus, the haematological and histological changes suggested that DIC was induced by rabbit haemorrhagic disease virus infection. Severe liver necrosis was considered to be a factor causing DIC by inducing a hypercoagulable condition in the systemic blood circulation.