Description of neurological mimics presented to the neurology service of a small animal referral hospital.

BACKGROUND: Clinicians observe that cats and dogs referred to neurology services often do not have an underlying neurological disorder. There has been no analysis of the frequency or categorisation of these neurological mimics. METHODS: Retrospective study of 520 cases was carried out. Data on signalment, presenting clinical signs, neurological examination findings and final diagnosis were collected. Final diagnoses were classified as primary neurological, non-neurological in origin but with neurological clinical manifestation, completely non-neurological (neurological mimics) or undiagnosed. Presenting clinical signs and neurological examination results were compared between neurological mimics and primary neurological cases using Chi-square or Fischer exact test. Relative risk (RR) was calculated for significant associations. RESULTS: A total of 74% were primary neurological conditions, 8% neurological mimics, 3% non-neurological with neurological manifestation and 15% undiagnosed. An animal referred for lameness was approximately five times more likely to be diagnosed as a neurological mimic than as a primary neurological disorder (RR = 5.42, p < 0.001). Cases with a normal neurological examination were approximately 15 times more likely to be a neurological mimic (RR = 14.97, p < 0.001). CONCLUSION: Thorough examination with consideration of alternative diagnoses is important when a neurological condition is suspected in an animal that presents with lameness or normal neurological examination.

Resting and postprandial serum bile acid concentrations in dogs with liver disease.

BACKGROUND: Serum bile acids (SBAs) are frequently measured in dogs. However, there is limited data comparing SBAs in different liver diseases diagnosed according to standardized histological criteria. OBJECTIVES: To compare resting and postprandial SBAs, and determine their sensitivity and specificity, for various liver diseases in dogs. ANIMALS: Three hundred and forty-one client-owned dogs with suspected liver disease that had a liver biopsy and SBAs measured. METHODS: Multicenter retrospective study. Cases were classified according to standardized histological criteria. The sensitivity and specificity of resting and postprandial SBAs for the diagnosis of each liver disease, and all liver diseases combined, were calculated. RESULTS: The median resting SBAs were highest in dogs with cirrhosis (98.8 µmol/L; range, 6-135) and congenital circulatory anomalies (CCa; 79.45 µmol/L; 0.3-705). The highest median postprandial concentrations were found in CCa (126 µmol/L; 0-726) and chronic hepatitis (CH; 54.3 µmol/L; 0-260). Using the cut-off value of 10 µmol/L, the highest sensitivities of resting SBAs were recorded in dogs with CCa (87.5%; 95% confidence interval, 76.8-94.4) and CH (81.1%; 71.5-88.6). The sensitivities of postprandial SBAs were the highest in cholangitis (100%; 47.8-100.0) and CCa (91.1%; 78.8-97.5). The specificities of resting and postprandial SBAs for all diseases were 49.3% (37.6-61.1) and 29.7% (15.9-47.0), respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: Postprandial SBAs are more sensitive but less specific than resting SBAs for the diagnosis of liver disease. There were dogs in all categories of liver disease with resting SBAs <10 and >90 µmol/L. Therefore, careful interpretation of both normal and elevated values is required.

Prednisolone therapy for chronic hepatitis in English springer spaniels: a prospective study of 12 cases.

BACKGROUND: English springer spaniels (ESS) show an increased risk of chronic hepatitis (CH). In a previous study of 68 ESS with CH, in which only one dog received corticosteroids, a median survival time of 189 days was noted. Some ESS with CH appear to improve with prednisolone treatment; therefore, we aimed to investigate the response to prednisolone in this breed. PARTICIPANTS: ESS with histologically confirmed idiopathic CH were treated with prednisolone 1-2 mg/kg/day. Nine female and three male ESS were enrolled (median age at diagnosis of five years). Patients were monitored clinically and had biochemistry samples taken to assess markers of hepatocellular damage and function. RESULTS: The mean starting dose of prednisolone was 1.1 mg/kg/day. All symptomatic patients showed an initial clinical improvement. Two cases were euthanased while receiving prednisolone. The median time since diagnosis is 1715 days (range: 672-2105 days) and the remaining patients are clinically well, with seven patients still receiving a mean dose of 0.4 mg/kg prednisolone every other day. Statistical analysis demonstrated significant (P<0.05) reductions in serum alkaline phosphatase, alanine aminotransferase and bilirubin following 2-4 weeks of prednisolone treatment. CONCLUSION: This study demonstrates improved clinical and biochemical parameters when some ESS with CH are managed with prednisolone and standard supportive treatments.

Retrospective evaluation of thoracic computed tomography findings in dogs naturally infected by Angiostrongylus vasorum.

Angiostrongylus vasorum (A. vasorum) is an important emerging disease of canidae. Cardiorespiratory signs are common in affected dogs, therefore thoracic imaging is critical for diagnosing and monitoring disease. Descriptions of thoracic computed tomography (CT) findings in dogs naturally infected with A. vasorum are currently lacking. Aims of this multicenter, retrospective study were to describe thoracic CT findings in a group of dogs with confirmed disease, determine whether any changes were consistent among dogs, and propose standardized terms for describing thoracic CT findings. Nine UK-based referral centers' clinical and imaging databases were searched for dogs that had a confirmed diagnosis of A. vasorum, and had undergone thoracic CT examination. Eighteen dogs, from seven of the centers, fulfilled the inclusion criteria. The lung lobes were divided into the following three zones and the CT changes described in each: pleural (zone 1), subpleural (zone 2), and peribronchovascular (zone 3). The predominent abnormality was increased lung attenuation due to poorly defined ground-glass opacity or consolidation. There were regions of mosaic attenuation due to peripheral bronchiectasis. Nine/18 (50%) dogs showed hyperattenuating nodules of varying sizes with ill-defined margins. The distribution always affected zones 1 and 2 with varied involvement of zone 3; this resulted in clear delineation between zones 2 and 3. Tracheobronchial lymphadenomegaly was frequently noted. Findings were nonspecific and there was considerable overlap with other pulmonary conditions. However, authors recommend that A. vasorum be considered a likely differential diagnosis for dogs with a predominantly peripheral distribution of lung changes.

Total serum bilirubin as a negative prognostic factor in idiopathic canine chronic hepatitis.

Total serum bilirubin (TBIL) is used as a prognostic factor in chronic hepatitis (CH) in human beings. To date, the authors are unaware of any studies looking at the value of TBIL as a prognostic factor in idiopathic canine CH. The objective of the current study was to assess if TBIL is a negative prognostic factor in idiopathic canine CH, and to identify other prognostic factors. Thirty-nine dogs with histologically confirmed idiopathic CH admitted to 2 referral centers between 1999 and 2010 were included in the study. Patients with concurrent diseases that could affect TBIL or the survival time were excluded. Total serum bilirubin was measured prior to liver biopsy, and CH was diagnosed according to standardized histological criteria. Survival time was calculated from time of diagnosis to time of death or euthanasia. Cox proportional hazard analysis was performed to identify prognostic factors. The mean survival time for the 39 dogs included in the analysis was 197 days (1-2,677), and the mean total serum bilirubin was 11 µmol/l (2-265). Total serum bilirubin was statistically significantly associated with survival (odds ratio = 1.082, P = 0.047) as were weight (odds ratio = 1.028, P = 0.028) and the presence of ascites (odds ratio = 6.758, P = 0.013). The current study demonstrates that TBIL could be used as an additional prognostic factor in canine CH.

Metagenomic study of the viruses of African straw-coloured fruit bats: detection of a chiropteran poxvirus and isolation of a novel adenovirus.

Viral emergence as a result of zoonotic transmission constitutes a continuous public health threat. Emerging viruses such as SARS coronavirus, hantaviruses and henipaviruses have wildlife reservoirs. Characterising the viruses of candidate reservoir species in geographical hot spots for viral emergence is a sensible approach to develop tools to predict, prevent, or contain emergence events. Here, we explore the viruses of Eidolon helvum, an Old World fruit bat species widely distributed in Africa that lives in close proximity to humans. We identified a great abundance and diversity of novel herpes and papillomaviruses, described the isolation of a novel adenovirus, and detected, for the first time, sequences of a chiropteran poxvirus closely related with Molluscum contagiosum. In sum, E. helvum display a wide variety of mammalian viruses, some of them genetically similar to known human pathogens, highlighting the possibility of zoonotic transmission.

DLA class II alleles and haplotypes are associated with risk for and protection from chronic hepatitis in the English Springer spaniel.

Chronic hepatitis (CH) is common in dogs in the United Kingdom. An increased prevalence of the disease is seen in the English Springer spaniel (ESS), and this breed suffer from a severe form with young to middle aged female dogs being predisposed. The disease shares histological features with those of human viral hepatitis, although the specific aetiological agent has not yet been identified. The aim of the current study was to investigate whether dog leucocyte antigen (DLA) class II alleles and haplotypes are associated with susceptibility/resistance to CH in the ESS. Sequence-based genotyping of the polymorphic exon 2 from DLA-DRB1, -DQA1 and -DQB1 class II loci were performed in 66 ESSs with CH and 84 healthy controls. There was a significant difference in the distribution of the protective alleles DRB1*00501 (3.0% vs. 12.0%, odds ratio [OR] = 0.23, 95% confidence interval [CI] = 0.06-0.74) and DQB1*00501 (3.8% vs. 12.0%, OR = 0.29, 95% CI = 0.09-0.85) between cases and controls. The haplotype DLA-DRB1*00501/DQA1*00301/DQB1*00501 was present in 11.9% of controls and 3.0% of cases and was significantly associated with protection against disease development (OR = 0.26, 95% CI = 0.08-0.80). There was a significant difference in the distribution of the risk alleles DRB1*00601 (14.4% vs. 6.5%, OR = 2.40, 95% CI = 1.10-5.63) and DQB1*00701 (14.4% vs. 6.5%, OR = 2.40, 95% CI = 1.10-5.63) between cases and controls. A risk haplotype (DLA-DRB1*00601/DQA1*005011/DQB1*00701) was present in 14.4% of cases and 6.5% of controls and conferred an elevated risk of developing CH with an OR of 3.13 (95% CI = 1.20-8.26). These results demonstrate that DLA class II is significantly associated with risk and protection from developing CH in ESSs.

Metagenomics and the molecular identification of novel viruses.

There have been rapid recent developments in establishing methods for identifying and characterising viruses associated with animal and human diseases. These methodologies, commonly based on hybridisation or PCR techniques, are combined with advanced sequencing techniques termed 'next generation sequencing'. Allied advances in data analysis, including the use of computational transcriptome subtraction, have also impacted the field of viral pathogen discovery. This review details these molecular detection techniques, discusses their application in viral discovery, and provides an overview of some of the novel viruses discovered. The problems encountered in attributing disease causality to a newly identified virus are also considered.

Comparison of semiquantitative test strips, urine protein electrophoresis, and an immunoturbidimetric assay for measuring microalbuminuria in dogs.

BACKGROUND: The presence of albumin in urine, even in small amounts, is always abnormal and usually reflects kidney dysfunction. Different techniques are commercially available for the measurement of microalbuminuria in dogs. OBJECTIVES: The purpose of this study was to compare the accuracy of semiquantitative test strips, urine protein electrophoresis, and a validated immunoturbidimetric assay in the measurement of microalbuminuria in dogs. METHODS: Urine samples were collected from 307 dogs presented to The Queen's Veterinary School Hospital, University of Cambridge, for a variety of clinical conditions. Urine was collected by midstream free catch (193/307, 63%), cystocentesis (89/307, 29%), or catheterization (25/307, 8%). Routine urinalysis was performed on all samples. Albumin was measured by using semiquantitative test strips, by agarose gel electrophoresis, and by an automated immunoturbidimetric assay designed for human samples (considered as the gold standard). The latter was validated using a purified canine albumin standard. RESULTS: The immunoturbidimetric assay had within-assay and between-assay coefficients of variation (CV) of 1.3% and 5.0%, respectively, overall recovery of 97.1%, and high linearity (r=.985). Of the samples with measurable albumin (>1.4 mg/L) by the immunoturbidimetric assay, 57/195 (29%) were negative for albumin using the semiquantitative test strips and 138/195 (71%) were positive. Urine protein electrophoresis (UPE) and immunoturbidimetric results had a concordance CV of 86%. CONCLUSIONS: UPE and semiquantitative test strips are less accurate than the automated immunoturbidimetric method for the measurement of albumin in canine urine.

Estimation of glomerular filtration rate via 2- and 4-sample plasma clearance of iohexol and creatinine in clinically normal cats.

OBJECTIVE: To compare 2 methods for estimation of glomerular filtration rate (GFR), study the effects of age and body size on GFR estimates, and provide a reference range for estimated GFR in clinically normal cats. ANIMALS: 57 cats. PROCEDURES: In each cat, GFR was estimated via plasma clearance of iohexol and creatinine. Results of a 1-compartmental model (CL1comp) were calibrated to a trapezoidal method estimate (CLtrap) by use of a correction formula applicable to dogs or humans and standardized to body weight; for iohexol clearance, data were also standardized to extracellular fluid volume (ECFV). For all 57 cats, method comparison was performed via agreement analysis. Reference ranges for GFR derived by the different methods were established by use of data from a subset of 51 cats after exclusion of 6 cats that were azotemic, Birman, or both. RESULTS: In 57 cats, mean CLtrap of creatinine was 0.29 mL/min/kg (13%) higher than CLtrap of iohexol. In 51 nonazotemic cats, mean CLtrap was 2.26 mL/min/kg for iohexol (reference range, 1.02 to 3.50 mL/min/kg) and 2.55 mL/min/kg for creatinine (reference range, 1.27 to 3.83 mL/min/kg). Values of GFR/kg or GFR standardized to liters of ECFV did not decrease with increasing age. A negative linear relationship was detected between body weight and estimated GFR/kg or GFR standardized to liters of ECFV. CONCLUSIONS AND CLINICAL RELEVANCE: Reference ranges for estimated GFR via plasma clearance of iohexol and creatinine should facilitate early detection of impaired renal function in cats, although body weight should be taken into account.

Heinz body haemolytic anaemia in a dog secondary to ingestion of a zinc toy: a case report.

A 6-year-old Labrador retriever was referred for investigation of severe lethargy and suspected immune-mediated haemolytic anaemia. Clinical examination revealed pale mucous membranes and jaundice. Haematology demonstrated large numbers of Heinz bodies and a marked anaemia, which was strongly regenerative. Serum zinc concentrations were markedly elevated. Analysis of a metal toy vomited by the dog 3 days prior to presentation revealed it to be composed of almost pure zinc. A diagnosis of haemolytic anaemia secondary to acute zinc toxicity was made and supportive therapy instigated. There was a subsequent decrease in numbers of Heinz bodies and a rise in the haematocrit, and the dog made an uneventful recovery. Acute zinc toxicity resulting in haemolytic anaemia is rarely observed, and this case was also unusual in that the main clinicopathological finding was the presence of numerous Heinz bodies without other evidence of oxidative damage to red blood cells.