Mycotic aneurysm caused by Graphium species in a dog

A case of Exophiala dermatitidis-induced phaeohyphomycosis in a cat with multiple intra-abdominal masses

Pus discharge containing black granular materials (1-2 mm in diameter) was found in the abdominal skin of a 13-year-old sterilized female cat. Abdominal ultrasonography revealed a large intra-abdominal mass with abundant blood flow beneath the skin lesion. Laparotomy revealed a large mass that adhered to the spleen and left kidney. Similar small lesions were found in the abdominal wall and mesentery. The masses were surgically removed along with the spleen and kidney. Histopathologically, the mass lesions consisted of granulomas with lesional pigmented fungi, and the cat was diagnosed with phaeohyphomycosis. Uisng genetic analysis, the Exophiala dermatitidis was identified as the causative pathogen.

Computed tomographic characteristics of confirmed and presumed noncutaneous pythiosis in 25 dogs

Pythium insidiosum is an aquatic oomycete that causes granulomatous infection in dogs, most commonly cutaneous and gastrointestinal. Ultrasonographic characteristics of gastrointestinal pythiosis have been described; occasionally, CT is utilized in the clinical setting, and CT features of pythiosis have not been published. The purpose of this retrospective, multicenter, descriptive study is to describe CT characteristics of noncutaneous canine pythiosis. The following CT parameters were recorded: lesion anatomic location, number, shape, margination, size, attenuation pre- and postcontrast, enhancement pattern, lymph nodes affected, other lesions identified, and presence of peritoneal effusion or steatitis. Descriptive statistics demonstrating the frequency of lesion appearances were performed. Twenty-five dogs with noncutaneous pythiosis lesions that underwent CT were included; 19 had primarily gastrointestinal infections, four primarily arterial infections, one intrathoracic and intra-abdominal infection, and one primary pulmonary infection. In dogs with primary gastrointestinal infection, lesions were most common at the ileocolic junction and were most frequently focal, well-defined, moderate to marked circumferential wall thickening that was homogeneous and smoothly marginated precontrast, with moderate heterogeneous contrast enhancement. Most dogs had involvement of multiple gastrointestinal regions. Of four dogs with primary arterial involvement, three had large aneurysmal dilatations of the cranial mesenteric artery with severe mural thickening. All dogs had regional lymphadenopathy, which was variable but generally mild. Nine dogs had peritoneal effusion; six dogs had steatitis. CT features of pythiosis can overlap with neoplasia, but pythiosis should be considered as a differential, especially in young dogs. Findings supported using CT as an adjunct imaging test for increasing clinical suspicion of noncutaneous pythiosis.

Annuloaortic ectasia in a four-month-old male Newfoundland dog: long-term follow-up and immunofluorescent study

A 4 month-old, 14.8 kg, male Newfoundland dog was presented for cardiovascular evaluation following detection of a heart murmur. Echocardiography revealed enlargement of the sinuses of Valsalva and marked, diffuse dilation of the ascending aorta (annuloaortic ectasia, AAE), with mild/equivocal subaortic stenosis (SAS). The dog was monitored over the duration of its lifetime, with serial echocardiograms performed at 5, 6, and 8 months and 1, 2, 3, 4, 8, and 10 years demonstrating persistent, diffuse dilation of the ascending aorta. The dog lived until it was 10 years old and died of metastatic carcinoma. Postmortem examination confirmed AAE and mild SAS. Hematoxylin and eosin and Weigert van Gieson stains were used to compare the ascending aorta to the descending aorta and left subclavian artery, and to compare aortic samples to those of three control dogs. Histopathologic evaluation revealed mild medial degeneration in the ascending aorta of all four dogs. Immunofluorescent microscopy was used for determining the deposition of proteins known to play a role in aortic aneurysms in humans: fibrillin-1 (FBN1), latent transforming growth factor beta binding protein 4 (LTBP4) and fibronectin. The ascending aorta of the AAE case demonstrated reduced deposition of FBN1, indicating that its loss may have contributed to aortic dilation. Diffuse, primary ascending aortic dilation is uncommonly reported in dogs; when it is, it carries a poor prognosis. This case provides an important example of marked dilation of the ascending aorta in a dog that lived with no associated adverse effects for 10 years.

Pulmonary Artery Aneurysm in a Greater Flamingo (Phoenicopterus roseus) Associated with Aspergillus fumigatus Infection

We report necropsy findings in a captive 60-year-old female greater flamingo (Phoenicopterus roseus) that died suddenly following rupture of a pulmonary artery aneurysm. Histologically, there was focally extensive, intramural granulomatous inflammation with intralesional fungal hyphae, and adjacent severe mixed-cell inflammation and acute haemorrhage at the rupture site. Aspergillus fumigatus was identified as the aetiological agent following DNA PCR amplification and sequencing from paraffin-embedded pulmonary artery tissue sections. The most likely explanation is that this lesion was a consequence of haematogenous spread, secondary to mycotic pneumonia or aerosacculitis, following aspiration of A. fumigatus conidiospores. However, no further fungal-related lesions were observed on gross or histopathological examination.

Computed tomographic and ultrasonographic findings of abdominal arterial pseudoaneurysms caused by systemic mycosis in dogs

OBJECTIVES

To describe multidetector CT and ultrasonographic characteristics of abdominal arterial pseudoaneurysms (segmental dilatations of an artery with a ruptured tunica intima) arising secondary to systemic mycosis in dogs.

MATERIALS AND METHODS

Retrospective study on dogs with confirmed histological diagnosis of a fungal pseudoaneurysm and the availability of multidetector CT or ultrasound images.

RESULTS

At the time of admission, the three dogs included in this study demonstrated segmental arterial dilation, irregular arterial wall thickening, and increased echogenicity or attenuation within the local perivascular fat on ultrasound and multidetector CT images. Follow-up examinations revealed progressive increase in arterial wall thickening and saccular dilation with formation of a pseudoaneurysm in affected vessels of two dogs.

CLINICAL SIGNIFICANCE

Multidetector CT and ultrasonography can be useful imaging modalities in the diagnosis and monitoring of abdominal arterial pseudoaneurysms caused by systemic mycosis.

AORTIC ANEURYSM, DISSECTION, AND RUPTURE IN SIX BILE-FARMED BEARS

Across China and Southeast Asia, over 17,000 bears are currently farmed for bile, predominantly for traditional Chinese medicines. Bears on farms in China are cage confined and undergo repeated daily bile extraction facilitated by surgically implanted catheters or gallbladder fistulas. Numerous health problems have been reported in bile-farmed bears including peritonitis, abdominal hernias, and extraction site abscessation. Between 2009 and 2014, five Asiatic black bears ( Ursus thibetanus) and one Asiatic black/Eurasian brown bear ( Ursus arctos arctos) hybrid, rescued from the bear bile industry in China, died from ruptured and/or dissecting aortic aneurysm. Medical records were reviewed and two bears exhibited no clinical signs prior to death. In four bears, clinical findings varied and included increased stereotypic behavior prior to death, epistaxis, retinal lesions, dysphagia, weight loss, and acute onset of hyporexia. On postmortem examination, hemopericardium with dissection and/or rupture of the ascending aorta and left ventricular wall hypertrophy were present in all cases. No evidence of infectious disease, connective tissue disorders, or congenital cardiac disease was identified. Based on these observations screening thoracic radiography was performed on all bears at the rescue center and aortic dilation was identified in 73 of 134 (54.5%) bile-extracted bears. To the authors' knowledge, aortic aneurysm, rupture, and/or dissection have not been previously reported in any bear species and the high prevalence in this population of bears suggests an association with bile-farming practices. Future studies are needed to investigate the etiopathogenesis of this condition to aid in early diagnosis and improved management of bears being rescued from bile farms across Asia.

Diagnostic imaging for the assessment of acquired abdominal vascular diseases in small animals: A pictorial review

Advances in interventional radiology and surgical techniques now allow complex abdominal diseases to be more successfully treated in small animals. Abdominal vascular alterations, acquired as individual process or as complication of other lesions such as neoplasia, can be life-threatening or at least greatly limit curative interventions of underlying diseases. Computed tomography (CT) and high-definition ultrasonography are now readily available in veterinary referral centers. Yet, there is little information currently available on the use of these modalities for the diagnosis and characterization of these vascular alterations. The purpose of this article is to review the CT and ultrasonographic findings of acquired vascular diseases in the abdomen of dogs and cats, using both the veterinary and human medicine literature as references, and highlighting essential concepts through figures.

First isolation of Schizophyllum commune in a harbor seal (Phoca vitulina)

To date, Schizophyllum commune infection has been identified in only humans and dogs. A 7-year-old female harbor seal (Phoca vitulina) died after exhibiting corneal opacity, anorexia, and labored respiration. At necropsy, phthisis of the left eyeball was detected, and multiple nodular lesions were observed in the thoracic and abdominal regions, especially in the lung, heart, and lymph nodes. Histopathologically, numerous hyphae were seen in granulomatous lesions in the eyes, lung, heart, and lymph nodules. An isolate on potato dextrose agar from the eyes, lung, and sputum yielded a rapidly growing white woolly mycelia with basidiocarps (fruiting bodies) at 37°C. A suitable temperature for mycelial growth was obtained at 25°C, although sustained growth also occurred at 37°C. The fungal isolate, KH-JPN15-011, had distinctive features including hyphae bearing spicules and clamp connections, which were consistent with the characteristics of basidiomycete fungus. The sequence of the internal transcribed spacer region of nuclear ribosomal DNA showed 99.67% (617 bp) similarity with those of S. commune Phylogenetic analysis showed that the present isolate is most closely related to the samples from the Old World. This is the first report of a fatal disease caused by S. commune in exotic animals. Previously reported human and canine infections have not included granulomatous endophthalmitis and myocarditis. After considering these and previous findings, there is a possibility that S. commune from the Old World may include numerous highly pathogenic strains.