Canine Circovirus 1 (CaCV-1) and Canine Parvovirus 2 (CPV-2): Recurrent Dual Infections in a Papillon Breeding Colony.

Recurrent outbreaks of sudden death and bloody diarrhea were reported in March 2013 and February 2014 in a breeding colony of Papillon dogs. During the first outbreak, 1 adult dog and 2 eight-month-old puppies died. During the second outbreak, 2 ten-week-old puppies died. One puppy from the first outbreak and 2 puppies from the second outbreak were examined at necropsy. Histologically, all 3 puppies had severe segmental crypt necrosis of the small intestine and marked lymphoid follicle depletion in the spleen and Peyer's patches. Real-time (RT) polymerase chain reaction (PCR) demonstrated abundant canine parvovirus (CPV-2) DNA (Ct<15) in the affected small intestine, and immunohistochemistry detected large amounts of CPV-2 antigen in intestinal crypt epithelium and Kupffer cells but few positive macrophages in lymphoid organs. All puppies had marked sinusoidal histiocytosis and multifocal granulomatous inflammation in mesenteric lymph nodes and spleen, prompting additional RT-PCR testing for canine circovirus 1 (CaCV-1). Very high levels of CaCV-1 DNA (Ct<13) were detected in small intestine, lymph nodes, and spleen. In situ hybridization for CaCV-1 detected rare positive nuclei of regenerating crypt epithelium but abundant amounts of CaCV-1 nucleic acid in the cytoplasm and nuclei of histiocytes in all lymphoid tissues, including granulomatous inflammatory foci and hepatic Kupffer cells. Significant levels of CaCV-1 DNA were detected in blood and serum (Ct as low as 13) but not feces from 3 surviving dogs at 2 months or 1 year after the outbreak, respectively. We hypothesize that CPV-2 infection predisposed dogs to CaCV-1 infection and ultimately resulted in more severe clinical disease.

Systematic review and meta-analysis of the accuracy of MRI and endorectal ultrasound in the restaging and response assessment of rectal cancer following neoadjuvant therapy.

AIM: Restaging imaging by MRI or endorectal ultrasound (ERUS) following neoadjuvant chemoradiotherapy is not routinely performed, but the assessment of response is becoming increasingly important to facilitate individualization of management. METHOD: A search of the MEDLINE and Scopus databases was performed for studies that evaluated the accuracy of restaging of rectal cancer following neoadjuvant chemoradiotherapy with MRI or ERUS against the histopathological outcome. A systematic review of selected studies was performed. The methodological quality of studies that qualified for meta-analysis was critically assessed to identify studies suitable for inclusion in the meta-analysis. RESULTS: Sixty-three articles were included in the systematic review. Twelve restaging MRI studies and 18 restaging ERUS studies were eligible for meta-analysis of T-stage restaging accuracy. Overall, ERUS T-stage restaging accuracy (mean [95% CI]: 65% [56-72%]) was nonsignificantly higher than MRI T-stage accuracy (52% [44-59%]). Restaging MRI is accurate at excluding circumferential resection margin involvement. Restaging MRI and ERUS were equivalent for prediction of nodal status: the accuracy of both investigations was 72% with over-staging and under-staging occurring in 10-15%. CONCLUSION: The heterogeneity amongst restaging studies is high, limiting conclusive findings regarding their accuracies. The accuracy of restaging imaging is different for different pathological T stages and highest for T3 tumours. Morphological assessment of T- or N-stage by MRI or ERUS is currently not accurate or consistent enough for clinical application. Restaging MRI appears to have a role in excluding circumferential resection margin involvement.

Distinguishing Intestinal Lymphoma From Inflammatory Bowel Disease in Canine Duodenal Endoscopic Biopsy Samples.

Inflammatory bowel disease (IBD) and intestinal lymphoma are intestinal disorders in dogs, both causing similar chronic digestive signs, although with a different prognosis and different treatment requirements. Differentiation between these 2 conditions is based on histopathologic evaluation of intestinal biopsies. However, an accurate diagnosis is often difficult based on histology alone, especially when only endoscopic biopsies are available to differentiate IBD from enteropathy-associated T-cell lymphoma (EATL) type 2, a small cell lymphoma. The purpose of this study was to evaluate the utility of histopathology; immunohistochemistry (IHC) for CD3, CD20, and Ki-67; and polymerase chain reaction (PCR) for antigen receptor rearrangement (T-cell clonality) in the differential diagnosis of severe IBD vs intestinal lymphoma. Endoscopic biopsies from 32 dogs with severe IBD or intestinal lymphoma were evaluated. The original diagnosis was based on microscopic examination of hematoxylin and eosin (HE)-stained sections alone followed by a second evaluation using morphology in association with IHC for CD3 and CD20 and a third evaluation using PCR for clonality. Our results show that, in contrast to feline intestinal lymphomas, 6 of 8 canine small intestinal lymphomas were EATL type 1 (large cell) lymphomas. EATL type 2 was uncommon. Regardless, in dogs, intraepithelial lymphocytes were not an important diagnostic feature to differentiate IBD from EATL as confirmed by PCR. EATL type 1 had a significantly higher Ki-67 index than did EATL type 2 or IBD cases. Based on the results of this study, a stepwise diagnostic approach using histology as the first step, followed by immunophenotyping and determining the Ki67 index and finally PCR for clonality, improves the accuracy of distinguishing intestinal lymphoma from IBD in dogs.

Beyond H&E: integration of nucleic acid-based analyses into diagnostic pathology.

Veterinary pathology of infectious, particularly viral, and neoplastic diseases has advanced significantly with the advent of newer molecular methodologies that can detect nucleic acid of infectious agents within microscopic lesions, differentiate neoplastic from nonneoplastic cells, or determine the suitability of a targeted therapy by detecting specific mutations in certain cancers. Polymerase chain reaction-based amplification of DNA or RNA and in situ hybridization are currently the most commonly used methods for nucleic acid detection. In contrast, the main methodology used for protein detection within microscopic lesions is immunohistochemistry. Other methods that allow for analysis of nucleic acids within a particular cell type or individual cells, such as laser capture microdissection, are also available in some laboratories. This review gives an overview of the factors that influence the accurate analysis of nucleic acids in formalin-fixed tissues, as well as of different approaches to detect such targets.

Polyomavirus-associated nephritis in 2 horses.

Polyomaviruses produce latent and asymptomatic infections in many species, but productive and lytic infections are rare. In immunocompromised humans, polyomaviruses can cause tubulointerstitial nephritis, demyelination, or meningoencephalitis in the central nervous system and interstitial pneumonia. This report describes 2 Standardbred horses with tubular necrosis and tubulointerstitial nephritis associated with productive equine polyomavirus infection that resembles BK polyomavirus nephropathy in immunocompromised humans.

Cutaneous lymphomas in European pet rabbits (Oryctolagus cuniculus).

Cutaneous lymphoma is a common skin neoplasm of pet rabbits in Europe but is rarely reported in pet rabbits in North America. These neoplasms have not been previously characterized, nor has the cause for the apparent predilection for cutaneous lymphoma in European pet rabbits compared with North American pet rabbits been investigated. In this retrospective study, the authors morphologically and immunohistochemically characterized 25 cutaneous lymphomas in European pet rabbits according to the World Health Organization classification. Tumors were classified as diffuse large B cell lymphomas, with 14 lymphomas exhibiting a centroblastic/centrocytic subtype and 11 tumors exhibiting a T cell-rich B cell subtype. To investigate a potential viral etiology of these lymphomas, 3 diffuse large B cell and 3 T cell-rich B cell lymphomas were evaluated by polymerase chain reaction for retroviral and herpesviral genes. Neither virus was detected. In contrast to other domestic animals, cutaneous lymphomas in European pet rabbits were highly pleomorphic and frequently contained multinucleated giant cells. Unexpectedly, the second most common subtype was T cell-rich B cell lymphoma, a subtype that is rare in species other than horses. Based on a limited number of samples, there was no support for a viral etiology that would explain the higher incidence of lymphoma in European pet rabbits compared with American pet rabbits. Further investigation into genetic and extrinsic factors associated with the development of these tumors is warranted.

Nested case-control study of feline calicivirus viruria, oral carriage, and serum neutralizing antibodies in cats with idiopathic cystitis.

BACKGROUND: The epidemiology of feline calicivirus (FCV) infection in cats with idiopathic cystitis (FIC) has not been investigated by contemporary molecular biologic methods. OBJECTIVES: To determine the prevalence of and evaluate risk factors for FCV viruria, oral carriage, and virus neutralizing (VN) antibodies in cats with and without FIC. ANIMALS: Cats with nonobstructive FIC (n = 47), obstructive FIC (n = 22), and FCV upper respiratory tract infection (URI; n = 25), and healthy client-owned (n = 18) and colony-housed (n = 24) cats. METHODS: Oropharyngeal secretions and urine were evaluated with a FCV p30 gene-based real-time reverse-transcriptase polymerase chain reaction (RT-PCR) assay. Serum VN antibody titers were determined by a modified microtiter assay. Associations of risk factors with log-transformed antibody titers were determined by multivariable generalized linear regression. RESULTS: FCV viruria was detected in 4 (6%) and 3 (12%) cats with FIC and URI, respectively. In 3 FIC cats, viruria was unassociated with detectable oral virus carriage. Oral FCV carriage was detected in 7 (10%) FIC cats. Median antibody titers were significantly higher in cats with obstructive FIC (1 :256), nonobstructive FIC (1:128), and URI (1:512) compared with healthy client-owned (1:16) and colony-housed (1:4) cats (P < .001). Other than disease, multivariate analysis did not identify any other explanatory variables for increased titers in cats with FIC or URI. CONCLUSIONS AND CLINICAL IMPORTANCE: FCV viruria was detected in cats with FIC and URI, however, its etiologic significance is uncertain. Serologic results suggest increased FCV exposure in FIC cats compared with controls. Further investigations are needed to clarify the potential role of FCV in FIC.

Diagnostic algorithm to differentiate lymphoma from inflammation in feline small intestinal biopsy samples.

Differentiating between inflammatory bowel disease (IBD) and small intestinal lymphoma in cats is often difficult, especially when only endoscopic biopsy specimens are available for evaluation. However, a correct diagnosis is imperative for proper treatment and prognosis. A retrospective study was performed using surgical and endoscopic intestinal biopsy specimens from 63 cats with a history of chronic diarrhea or vomiting or weight loss. A diagnosis of lymphoma or inflammation was based on microscopic examination of hematoxylin and eosin (HE)-stained sections alone, HE-stained sections plus results of immunohistochemical labeling (IHC) for CD3e and CD79a, and HE staining, immunophenotyping, and polymerase chain reaction (PCR) results for B and/or T cell clonality. In addition, various histomorphologic parameters were evaluated for significant differences between lymphoma and IBD using Fisher's exact test. The sensitivity and specificity of each parameter in the diagnosis of lymphoma were also determined. Results of Bayesian statistical analysis demonstrated that combining histologic evaluation of small intestinal biopsy specimens with immunophenotyping and analysis of clonality of lymphoid infiltrates results in more accurate differentiation of neoplastic versus inflammatory lymphocytes. Important histologic features that differentiated intestinal lymphoma from IBD included lymphoid infiltration of the intestinal wall beyond the mucosa, epitheliotropism (especially intraepithelial nests and plaques), heterogeneity, and nuclear size of lymphocytes. Based on the results of this study, a stepwise diagnostic algorithm that first uses histologic assessment, followed by immunophenotyping and then PCR to determine clonality of the lymphocytes, was developed to more accurately differentiate between intestinal lymphoma and IBD.

Meningoencephalitis in a polar bear caused by equine herpesvirus 9 (EHV-9).

A 12-year-old female polar bear (Ursus maritimus) developed a sudden onset of muscle tremors, erratic circling, increased blinking, head shaking, and ptyalism, which progressed to partial and generalized seizures. Ancillary diagnostic tests were inconclusive, and the only significant laboratory finding was nonsuppurative pleocytosis of cerebrospinal fluid. Euthanasia was elected. Microscopic evaluation demonstrated multifocal, random nonsuppurative meningoencephalitis involving most prominently the rostral cerebral cortex, as well as the thalamus, midbrain, and rostral medulla. Lesions consisted of inflammation, neuronal necrosis, gliosis, and both neuronal and glial basophilic intranuclear inclusion bodies. Immunohistochemistry with a polyclonal antibody reactive to several equine herpesviruses was positive within affected areas of the brain, and polymerase chain reaction conclusively demonstrated the presence of only equine herpesvirus 9. The clinical and morphologic features of this case resemble other fatal herpesvirus encephalitides derived from interspecies transmission and underscore the need for extreme caution when managing wild or captive equids.

Detection of group C rotavirus in juvenile ferrets (Mustela putorius furo) with diarrhea by reverse transcription polymerase chain reaction: sequencing and analysis of the complete coding region of the VP6 gene.

Nine juvenile ferrets (Mustela putorius furo) with a history of diarrhea were severely dehydrated and had distended abdomens and thin-walled small intestines that contained gas and fluid. Histologically, small intestines exhibited acute superficial atrophic enteritis. Transmission electron microscopy of the small intestine showed rotavirus-like particles within apical vacuoles. Reverse transcription polymerase chain reaction (RT-PCR) was negative for group A rotavirus. A group C rotavirus-specific RT-PCR assay was developed using consensus primers designed from the alignment of VP6 gene sequences of porcine, bovine, and human strains. A 182-bp product of the VP6 gene was sequenced and showed significant similarity to group C rotavirus VP6 sequences. This strain was designated "Ferret Rota C-MSU." The entire coding sequence of VP6 was determined and compared with other rotaviruses. Ferret Rota C-MSU virus was found to be most closely related to Shintoku group C rotavirus. This is the first definitive identification of a group C rotavirus in ferrets, based upon RT-PCR, sequencing, and genetic analysis.

Clinico-pathologic features of fatal disease attributed to new variants of endotheliotropic herpesviruses in two Asian elephants (Elephas maximus).

The first herpesviruses described in association with serious elephant disease were referred to as endotheliotropic herpesviruses (EEHV) because of their ability to infect capillary endothelial cells and cause potentially fatal disease. Two related viruses, EEHV1 and EEHV2, have been described based on genetic composition. This report describes the similarities and differences in clinicopathologic features of 2 cases of fatal endotheliotropic herpesvirus infections in Asian elephants caused by a previously unrecognized virus within the betaherpesvirus subfamily. EEHV3 is markedly divergent from the 2 previously studied fatal probosciviruses, based on polymerase chain reaction sequence analysis of 2 segments of the viral genome. In addition to ascites, widespread visceral edema, petechiae, and capillary damage previously reported, important findings with EEHV3 infection were the presence of grossly visible renal medullary hemorrhage, a tropism for larger veins and arteries in various tissues, relatively high density of renal herpetic inclusions, and involvement of the retinal vessels. These findings indicate a less selective organ tropism, and this may confer a higher degree of virulence for EEHV3.

Clinicopathologic features of a systemic coronavirus-associated disease resembling feline infectious peritonitis in the domestic ferret (Mustela putorius).

From 2002 to 2007, 23 ferrets from Europe and the United States were diagnosed with systemic pyogranulomatous inflammation resembling feline infectious peritonitis (FIP). The average age at the time of diagnosis was 11 months. The disease was progressive in all cases, and average duration of clinical illness was 67 days. Common clinical findings were anorexia, weight loss, diarrhea, and large, palpable intra-abdominal masses; less frequent findings included hind limb paresis, central nervous system signs, vomiting, and dyspnea. Frequent hematologic findings were mild anemia, thrombocytopenia, and hypergammaglobulinemia. Grossly, whitish nodules were found in numerous tissues, most frequently the mesenteric adipose tissue and lymph nodes, visceral peritoneum, liver, kidneys, spleen, and lungs. One ferret had a serous abdominal effusion. Microscopically, pyogranulomatous inflammation involved especially the visceral peritoneum, mesenteric adipose tissue, liver, lungs, kidneys, lymph nodes, spleen, pancreas, adrenal glands, and/or blood vessels. Immunohistochemically, all cases were positive for coronavirus antigen using monoclonal antibody FIPV3-70. Electron microscopic examination of inflammatory lesions identified particles with coronavirus morphology in the cytoplasm of macrophages. Partial sequencing of the coronavirus spike gene obtained from frozen tissue indicates that the virus is related to ferret enteric coronavirus.

Gastric dilatation and necrosis in bulimia: a case report.

Gastric dilatation and perforation is a rare complication in anorexia/bulimia sufferers. We describe a 24 year old female who presented with severe abdominal pain and vomiting, in whom radiographs demonstrated gross gastric dilatation and subsequent perforation. Although gastric perforation is rare, one can anticipate a rising incidence, with the apparent increase in the incidence of bulimia.

Hide and seek: pre-operative ultrasonic localization of non radio-opaque foreign bodies.

Ultrasound has long been used as a diagnostic and therapeutic tool in surgery. We have extended its use to hand surgery, where is has several applications. Non radio-opaque foreign body extraction is invariably a frustrating exercise of 'hide and seek'. Accurate pre-operative localization with ultrasound illustrating size, shape, depth, soft tissue and bony relationships can ensure rapid and complete removal. Several cases are presented to demonstrate the use of ultrasound for the detection of non radio-opaque foreign bodies. The technique used will be described. We feel pre-operative localization by ultrasound is a useful technique to assist with the removal of non radio-opaque foreign bodies.