Multifocal pyogranulomatous osteomyelitis resembling chronic recurrent multifocal osteomyelitis in a lemur

Chronic recurrent multifocal osteomyelitis is a rare inflammatory bone disease of children and adolescents that is characterized by localized swelling and pain in the clavicles and long bones of the limbs. Diagnosis of chronic recurrent multifocal osteomyelitis is made from clinical signs, characteristic radiographic and histopathologic findings, and negative results of microbial cultures. Treatment of chronic recurrent multifocal osteomyelitis in humans includes administration of nonsteroidal anti-inflammatory drugs or immune modulators, which may be effective in lemurs.     

Fatal toxoplasmosis in a red lory (Eos bornea)

Toxoplasmosis was diagnosed in a 3-week-old red lory (Eos bornea). Grossly, there was hepatomegaly and pulmonary consolidation. The salient microscopic lesions were multifocal necrotizing mycocarditis, interstitial pneumonia with multifocal necrosis and vasculitis, and multifocal necrotizing hepatitis with periacinar hepatocellular necrosis. Toxoplasma gondii-like organisms were observed in lung, heart, and liver by light and electron microscopy. The organisms in tissues stained with anti-T. gondii serum using an immunohistochemical method.     

Multifocal oligodendroglioma in three dogs

This report describes the clinical, histopathologic, and imaging findings of multifocal oligodendrogliomas from three canine patients. Clinical history varied but included seizure activity and behavior changes. Neurologic examination abnormalities included ataxia, proprioceptive deficits, cranial nerve deficits, and changes in mentation. MRI in one patient revealed multifocal brain lesions; however, the MRI was normal in another one of the patients. Histopathologic evaluation identified multifocal neoplastic infiltrates in all three patients involving the cerebral cortex, brainstem, and spinal cord, with leptomeningeal extension in two of the three patients. All three patients were euthanized due to progression of their neurologic condition and/or complications due to aspiration pneumonia. Oligodendrogliomas should be considered a differential diagnosis for patients with multifocal brain disease.     

Diagnostic exercise: papulovesicular dermatitis in rhesus macaques (Macaca mulatta)

Eleven rhesus monkeys developed multifocal erythematous and a vesicular rash. Most recovered spontaneously, but a 21-year-old female became moribund and was euthanized. Findings were of vesicular dermatitis and widespread multifocal hemorrhagic necrosis of the lungs and other viscera, with intralesional intranuclear inclusions. Simian varicella virus was identified as the cause by polymerase chain reaction analysis and serologic testing.     

Paratuberculosis in a mandrill (Papio sphinx).

A 2.5-year-old captive female mandrill (Papio sphinx) died following a protracted course of intermittent abdominal bloat, diarrhea, and severe weight loss. Necropsy revealed emaciation and marked gastrointestinal distention with gas and ingesta. Histologic evaluation revealed severe diffuse granulomatous enterocolitis and mesenteric lymphadenitis with massive numbers of 1-2-microm acid-fast bacilli within macrophages. Additionally, there was moderate to severe multifocal myocardial and vascular amyloidosis, moderate multifocal pyogranulomatous interstitial pneumonia with no acid-fast bacteria, and moderate multifocal glossal candidiasis. Samples of feces, ileum, and colon were positive for Mycobacterium avium subsp. paratuberculosis by radiometric culture and a polymerase chain reaction-amplified DNA probe specific for the insertion sequence IS900 of this organism.     

Fatal cerebrospinal disease caused by Baylisascaris procyonis in domestic rabbits

Infection with Baylisascaris procyonis, the common roundworm of raccoons, was found to be the cause of an epizootic of fatal CNS disease in domestic rabbits (Oryctolagus cuniculus). Clinical signs included torticollis, ataxia, tremors, and falling. Gross lesions were limited to white, raised nodules (1 to 1.5 mm) on the epicardium, endocardium, and liver serosa, and they were found to be larval granulomas. Microscopic lesions included multifocal myocarditis, multifocal hemorrhagic tracks and associated necrosis and inflammation in the liver, multifocal eosinophilic myositis, focal nephritis, and mild interstitial pneumonia; larval granulomas were seen in the heart, liver, lung, and mandibular salivary gland. Lesions in the brain consisted of multifocal areas of necrosis and inflammation in the cerebrum, cerebellum, midbrain, and medulla, with accompanying perivascular leukocyte aggregates and neuronal and axonal degeneration. Large numbers of large ascarid larvae were seen in the brain. Epidemiologically, infection was linked to the use of contaminated straw from a barn used by raccoons. On the basis of this study as well as that of similar studies, it was concluded that barn use and contamination by raccoons may be an important source of infection of animals and possibly man with this parasite.     

The clinical presentation and surgical treatment of verrucous dermatitis lesions in a draught horse

Verrucous pastern dermatitis is a progressive inflammatory skin disease commonly involving the palmar or plantar aspects of the pasterns of horses. There are no reports of successful surgical treatment for multifocal circumscribed verrucous masses in the chronic stages of verrucous pastern dermatitis. A combination of sharp dissection and electrocautery was used to resect numerous multifocal circumscribed verrucous masses from the distal hindlimb of an 11-year-old gelding draught horse. There was no evidence of significant regrowth or complications at a 24 month postoperative examination.     

Canine multifocal retinopathy caused by a BEST1 mutation in a Boerboel

A 7‐month‐old male intact Boerboel presented to the Cummings School of Veterinary Medicine at Tufts University for the evaluation of ocular discharge. Bilateral multifocal serous retinal detachments were noted on fundus examination as an incidental finding. Genetic testing confirmed the dog to be homozygous for a mutation in the BEST1 gene, where a C₇₃T/R₂₅X change results in premature termination codon. Further testing, including electroretinography and optical coherence tomography (OCT), demonstrated that there was no evidence of retinal photoreceptor dysfunction and confirmed that observed lesions were characteristic of canine multifocal retinopathy. No progression of the lesions was noted 3 months after the initial examination. To the authors’ knowledge, this is the first report of canine multifocal retinopathy in the Boerboel breed.     

Pansteatitis in a free-ranging red-tailed hawk (Buteo jamaicensis).

A free-ranging juvenile female red-tailed hawk (Buteo jamaicensis) that was unable to fly was admitted to a rehabilitation center and died 1 day later. Hematology and serum chemistry abnormalities included moderate regenerative anemia, elevated creatine kinase, and hyperphosphatemia. Necropsy revealed a generalized steatitis, and histology showed a necrotizing and granulomatous pansteatitis with intralesional pigment compatible with ceroid. There was also moderate diffuse myodegeneration, mild multifocal cardiomyopathy, and mild multifocal hepatic necrosis. These changes and lesions resemble those caused by vitamin E deficiency in mammals and fish-eating birds.     

Clostridium piliforme infection in two farm-raised white-tailed deer fawns (Odocoileus virginianus) and association with copper toxicosis

Necropsy of 2 white-tailed deer fawns who died acutely revealed diarrhea and melena in case No. 1 and no gross changes in case No. 2. Histologically, the livers of both deer displayed multifocal coagulative necrosis, with infiltrations of neutrophils, macrophages, and lymphocytes. By Warthin-Starry staining, bundles of filamentous bacteria were identified within hepatocytes at the periphery of the necrotic foci in case No. 1. There was multifocal myocardiocyte necrosis in case No. 1 and multifocal lymphoid necrosis of the Peyer's patches in case No. 2. Clostridium piliforme 16S ribosomal ribonucleic acid gene was detected in both livers by polymerase chain reaction (PCR) with C. piliforme-specific primers. The liver copper levels in both cases were normal to slightly elevated. The kidney copper level in case No. 2 was elevated. This represents the first published cases of Tyzzer's disease in deer, a novel use of PCR for the diagnosis of C. piliforme infection, and a possible association between copper toxicosis and Tyzzer's disease.     

An outbreak of fowl cholera in ring-necked pheasants (Phasianus colchicus)

A total of 120 ring-necked pheasants from a 3000-bird flock in Zeeland, MI, died over a 3-day period. Clinical signs included sudden death, diarrhea, and limping. At necropsy, hepatomegaly with multifocal cream-colored foci randomly distributed throughout the parenchyma was observed in diseased birds. Additionally, the spleen was enlarged up to three times its normal size and had a marbled appearance. Microscopically, there was multifocal splenic and hepatic necrosis with intralesional rod-shaped bacteria. Pasteurlla multocida serotype 3/4 was isolated from liver and spleen. In this paper, we report an outbreak of acute fowl cholera in ring-necked pheasants.     

Dual infection with Pythium insidiosum and Blastomyces dermatitidis in a dog

A 4-year-old male neutered Labrador Retriever with severe gastrointestinal signs, but no respiratory signs, was diagnosed with multifocal pyogranulomatous gastritis, enteritis, and lymphadenitis with intralesional hyphae and multifocal pyogranulomatous pneumonia with intralesional yeast. Based on cytologic evaluation, histologic examination with special stains, and immunohistochemical analysis of tissues collected antemortem or at necropsy, dual infections with Pythium insidiosum and Blastomyces dermatitidis were detected and are reported for the first time.     

Disseminated blastomycosis in a rhesus monkey (Macaca mulatta).

An 8-year-old male rhesus monkey (Macaca mulatta) died following a 6-day illness consisting of progressive depression, anorexia, labored abdominal breathing, coughing, and tachypnea. Gross necropsy findings included severe multifocal (miliary) granulomatous pneumonia, granulomatous splenitis, and multifocal cerebral abscesses. Histologic examination revealed 10-15-microm broad-based budding organisms within pyogranulomatous inflammatory lesions in the lung, tracheobronchial lymph node, brain, spleen, and liver. The distribution of extrapulmonary lesions was intermediate between that described for dogs and that described for humans. These findings were consistent with blastomycosis, which is previously unreported in nonhuman primates.     

Multisystemic granulomatous inflammation in a horse

A one-year-old Thoroughbred filly was examined because of poor body condition and reluctance to move its neck. Complete blood count revealed leukocytosis (15,700 WBC/microliters) and hyperproteinemia (8 g/dl). Radiography of the cervical vertebrae revealed multifocal lesions of bone lysis surrounded by zones of sclerosis. The horse was euthanatized and necropsied. Granulomatous lesions were identified in the heart, spleen, lungs, bones, and lymph nodes. The multifocal granulomatous inflammatory lesions in this horse were suggestive of mycobacteriosis.     

Infiltrative angiolipoma of the parotid salivary gland in a dog

Solitary benign angiolipoma and infiltrative angiolipoma are rare tumours in dogs. Angiolipomata can be distinguished histologically from lipomata by the large number of tightly packed blood vessels seen between the adipocytes with multiple fibrin thrombi occupying some of the vessels' lumens. The dog presented with a solitary slow-growing mass in the cervical region. Histopathology revealed multifocal to coalescing single or clusters of blood-filled vessels lined by flattened endothelial cells with narrow, elongated, basophilic nuclei. These regions were embedded in adipose tissue with multifocal areas of intervascular remnants of differentiated serous salivary glandular tissue with multifocal small ducts. Fibrin thrombi occupied a few of the vessel lumens. A histological diagnosis of infiltrative angiolipoma was made. On computed tomography, the mass was bilobed with a suspected primary component involving the right parotid gland which was grossly enlarged. The mass had a slightly hypoattenuating mottled to lobulated appearance with a few hyperattenuating mineralised specks throughout. Hounsfield units of the mass ranged between 40 and 45, which was less than the 60-65 of the contralateral salivary glands and cranial musculature. Post contrast images showed no contrast enhancement of 90% of the mass with only a band of peripheral contrast uptake of the affected lateral lobe.     

Unusual multifocal granulomatous disease caused by actinomycetous bacteria in a nestling Derbyan parrot (Psittacula derbiana)

A nestling Derbyan parrot ( Psittacula derbiana ) was presented with unusual subcutaneous swellings of the thigh regions, and poor growth. Histological examination revealed actinomycetous bacteria associated with multifocal systemic granulomas. The clinical and pathological findings of the case are presented, and some relevant aspects of actinomycetous bacterial infections in mammals and birds are discussed. Although granulomatous disease is encountered at times in avian species, the actinomycetous bacteria ( Nocardia and Actinomyces spp.) have rarely been reported in association with multifocal granulomatous disease in birds.     

Severe ulcerative and granulomatous pinnal lesions with granulomatous sebaceous adenitis in unrelated vizslas

Granulomatous sebaceous adenitis (GSA) is uncommon in dogs; however, certain breed predilections exist. In this report, three cases of GSA in unrelated vizslas have been described. All cases initially presented with episodes of otitis externa followed by severe inner pinnal lesions. In one case, multifocal coalescing inner pinnal ulceration appeared 4 wk prior to the occurrence of the skin lesions. The other two cases presented with simultaneous pinnal and skin lesions following episodes of bilateral otitis. The pinnae were diffusely erythematous and had multiple coalescing erosions and ulcers. The body lesions consisted of multifocal alopecia, papules, and fine scales. Biopsies of the skin and pinnae confirmed GSA. Two dogs responded to treatment with synthetic retinoids and cyclosporin A, respectively. One dog was not treated, and the owners preferred euthanasia when the ear lesions recurred and did not respond to glucocorticoids. To the best of the authors' knowledge, GSA with multifocal coalescing ulcerative pinnal lesions has not previously been reported.     

Fatal cutaneous mycosis in tentacled snakes (Erpeton tentaculatum) caused by the Chrysosporium anamorph of Nannizziopsis vriesii.

The fungus Chrysosporium anamorph of Nannizziopsis vriesii was identified as the cause of fatal, multifocal, heterophilic dermatitis in four freshwater aquatic captive-bred tentacled snakes (Erpeton tentaculatum). Pale, 1- to 4-mm focal lesions involving individual scales, occurred primarily on the head and dorsum. Histology showed multifocal coagulation necrosis of the epidermis, with marked heterophilic infiltration without involvement of the underlying dermis. Septate, irregularly branched hyphae, and clusters of 4- to 8- by 2- to 3-microm rod-shaped cells (arthroconidia) were present within the lesions and in a superficial crust. Failure to maintain an acidic environment was likely a predisposing factor in the development of these lesions.     

Disseminated blastomycosis in two California sea lions (Zalophus californianus).

Two captive California sea lions (Zalophus californianus) from different facilities were diagnosed with disseminated blastomycosis. The first, a 12-yr-old male, died after a 3-wk history of progressive anorexia and lethargy. Gross examination revealed acute jejunitis with focal perforation and associated peritonitis, along with severe purulent bronchopneumonia. The second, a 15-yr-old female, was euthanized after a 2-wk history of severe cutaneous ulceration and declining clinical condition. Gross examination revealed severe pyogranulomatous bronchopneumonia and ulcerative dermatitis. Histopathologic examination in both individuals revealed severe multifocal subacute to chronic pyogranulomatous pneumonia associated with massive numbers of fungal organisms morphologically compatible with Blastomyces sp. Fungal organisms were 8-20-microm-diameter broad-based budding yeasts with thick, refractile, double-contoured walls. The male sea lion had multifocal transmural Blastomyces-induced enteritis with subsequent rupture and peritonitis. The organism was also present in the liver, with minimal associated inflammation. The female had severe multifocal pyogranulomatous ulcerative dermatitis associated with large numbers of intralesional fungal organisms. Dissemination to the spleen had occurred in both animals. A serologic immunodiffusion test for Blastomyces dermatitidis was positive in the male. The presumptive primary pathogen in both cases was Blastomyces dermatitidis.     

Mycobacterium infection in a gray-cheeked parakeet

A gray-cheeked parakeet, approximately 3 years of age, was submitted for necropsy. Clinical signs included diarrhea, decreased feed consumption, fluffing of feathers, shivering, weight loss, and limping. Necropsy revealed enlargement and pale discoloration of the spleen and intestines. The liver contained multifocal pale foci. Granulomas, some of which had necrotic centers, were present along the subserosa of the intestinal tract. Microscopic examination revealed diffuse granulomatous splenitis, enteritis, and multifocal granulomatous hepatitis. Numerous acid-fast bacteria were demonstrated in the spleen, liver, and intestine.