Cerebrospinal fluid analysis and magnetic resonance imaging in the diagnosis of neurologic disease in dogs: a retrospective study

BACKGROUND: Diagnosis of central nervous system (CNS) abnormalities in dogs can be challenging antemortem. Historically, cerebrospinal fluid (CSF) analysis has been used for routine diagnostic evaluation of animals with suspected neurologic disease; however, with increasing availability of magnetic resonance (MR) imaging, the need for concurrent CSF analysis may be questioned. OBJECTIVE: The purpose of this study was to retrospectively assess and compare the diagnostic information contributed from MR imaging and CSF analysis in a population of dogs presenting with neurologic disease. METHODS: Results of concurrent MR imaging and CSF analysis were evaluated in dogs presented for neurologic diseases. Based on clinical diagnosis, the sensitivity of CSF analysis and MR imaging for detecting a nervous system abnormality was calculated. Dogs with diagnoses confirmed by other diagnostic modalities were also evaluated separately. RESULTS: A total of 256 dogs were included in the study. For clinical diagnoses in which abnormalities were expected, MR imaging abnormalities were found in 89% and CSF abnormalities in 75% of dogs; CSF abnormalities were more common than MR imaging abnormalities only in inflammatory CNS disease. The majority of CSF abnormalities were nonspecific; an etiologic diagnosis was determined in only 2% of CSF samples. MR imaging excelled in detecting structural disorders, revealing 98% of vertebral abnormalities. In confirmed cases (n = 55), 76% of MR images and 9% of CSF samples were diagnostic. When intervertebral disk disease (IVDD) and vertebral malformation were excluded from analysis (n = 16 remaining), 25% of MR images and 6% of CSF cytology results were highly indicative of the confirmed diagnoses; CSF titer results provided the diagnosis in 25% of these cases. CONCLUSION: CSF analysis may not be necessary when MR findings of IVDD or vertebral malformation/instability are obvious; however, when the cause of neurologic disorder is uncertain, concurrent MR imaging and CSF analysis provides the greatest assistance in establishing a clinical diagnosis.     

A two-step species-specific 16S rRNA PCR assay for the detection of Taylorella equigenitalis in horses

: A two-step PCR assay was developed for the molecular detection of Taylorella equigenitalis, a Gram-negative genital bacterial pathogen in horses. Two specific oligonucleotide primers (TE16SrRNABCHf [25mer] and TE16SrRNABCHr [29mer]) were designed from multiple alignments of the 16S rRNA gene loci of several closely related taxa, including T. asinigenitalis. Subsequent enhanced surveillance of 250 Thoroughbred animals failed to detect the presence of this organism directly from clinical swabs taken from the genital tract of mares and stallions. Such a molecular approach offers a sensitive and specific alternative to conventional culture techniques, and has the potential to lead to improved diagnosis and subsequent management of horses involved in breeding programmes.     

An update on FIV and FeLV test performance using a Bayesian statistical approach

BACKGROUND: Screening tests for feline retroviruses are thought to have high sensitivity and specificity, although previous studies that evaluated these tests have limitations. Novel statistical approaches have been developed that allow the estimation of sensitivity and specificity in situations where the true state of the disease in individual animals cannot be assured. OBJECTIVE: The purpose of this study was to evaluate the sensitivity and specificity of a variety of retrovirus tests, including some screening tests, in a population of cats potentially infected with either feline leukemia virus (FeLV) and/or feline immunodeficiency virus (FIV) by using a Bayesian statistical approach. METHODS: Four hundred and ninety blood samples from cats being evaluated for FIV infection were tested by 2 rapid immunomigration tests (Witness single [WS], Witness combi [WC]) and a plate-based ELISA (Petcheck) for FIV antibody, and by a newly designed real-time polymerase chain reaction (PCR) assay for FIV provirus. Four hundred and ninety-five blood samples from cats being evaluated for FeLV infection were tested by 2 rapid immunomigration tests (WS, WC) and a plate-based ELISA (Petcheck) for FeLV antigen, and by a FeLV virus isolation technique. Results were then analyzed by using a Bayesian statistical method. RESULTS: For FIV tests, median sensitivity estimates were 0.98 for WS, 0.97 for WC, 0.98 for ELISA, and 0.92 for PCR. Median specificity estimates were 0.96 for WS, 0.96 for WC, 0.93 for ELISA, and 0.99 for PCR. For FeLV tests, median sensitivity estimates were 0.97 for WS, 0.97 for WC, 0.98 for ELISA, and 0.91 for virus isolation. Median specificity estimates were 0.96 for WS, 0.96 for WC, 0.98 for ELISA, and 0.99 for virus isolation. CONCLUSIONS: The use of Bayesian statistical methods overcomes a variety of methodologic problems associated with diagnostic test evaluations, including the lack of a definitive reference test. The sensitivity and the specificity of all 6 evaluated screening tests was high: however, specificity estimates were slightly lower than those reported by most recent studies.     

Bilateral mandibular pyogranulomatous lymphadenitis and pulmonary nodules in a dog with Bartonella henselae bacteremia

This report describes a 2-year-old collie dog with pulmonary nodules, visualized by computed tomographic (CT) scan, with evidence of Bartonella henselae bacteremia and pyogranulomatous lymphadenitis. Clinical signs resolved with antimicrobial therapy.     

Expression of erythropoietin in cats treated with a recombinant adeno-associated viral vector

OBJECTIVE: To characterize the biological effects of IM administration of a recombinant adeno-associated virus serotype 2 (rAAV2) vector containing feline erythropoietin (fEPO) cDNA and determine whether readministration of the vector or removal of muscle tissue at the injection sites alters those effects. ANIMALS: 10 healthy 7-week-old specific pathogen-free cats. PROCEDURE: Cats received 1 X 10(7) infective units (iU; n = 3), 1 X 10(8) iU (3), or 1 X 10(9) iU (2) of rAAV2-fEPO vector IM (day 0). Two control cats received an rAAV2 vector containing the LacZ gene (1 X 10(9) iU, IM). In all cats, hematologic variables and serum fEPO concentration were measured at intervals; anti-rAAV2 antibody titer was measured on day 227. In cats that did not respond to treatment, the rAAV2-fEPO vector was readministered. Injection sites were subsequently surgically removed. RESULTS: Compared with control cats, cats treated with 1 X 10(9) iU of rAAV2-fEPO vector had increased Hct and serum fEPO concentrations. One of these cats developed pure RBC aplasia; its Hct normalized following injection site excision. Cats receiving lower doses of vector had no response; on retreatment, 1 of those cats developed sustained erythrocytosis that persisted despite injection site removal and the others did not respond or responded transiently. Antibodies against rAAV2 were detected in all vector-treated cats. CONCLUSIONS AND CLINICAL RELEVANCE: Gene therapy may be an effective treatment for cats with hypoproliferative anemia. However, rAAV2-fEPO vector administration may result in pure RBC aplasia or pathologic erythrocytosis, and injection site removal does not consistently abolish the biological response.     

Comparison of the microtitration agglutination test and the enzyme-linked immunosorbent assay for the detection of herds affected with swine dysentery

A method was designed to evaluate and compare the microtitration agglutination test (MAT) and the enzyme-linked immunosorbent assay (ELISA) to detect antibodies in swine sera to Treponema hyodysenteriae and thereby establish a method for determining the prevalence of swine dysentery (SD) in herds. According to sampling criteria based on the hypergeometric distribution, sera were collected from 3 age groups of swine from farms having a history of SD on the premises (SD+) recently or being free of the disease (SD-). The highest degree of test sensitivity was obtained when sera from market age swine were evaluated with the ELISA. Of 14 SD+ herds from which sera were obtained from market-age swine, 13 were positive with the ELISA (93%); none of the 8 SD- herds was positive. The detection rates of individual swine in the SD+ herds for the 2 tests by age group were as follows: MAT--adult swine 1.4%, market-age swine 6%, and weaned pigs 0.8%; ELISA--adult swine 16%, market swine 31%, and weaned pigs 0.5%.     

Post-emergence application of herbicides and growth regulators on soybean growth and agronomic performance

Journal of Crop Science and Biotechnology - Plant lodging is among the factors that limit the productive potential of the soybean crop. Growth regulators or even herbicides may be used in pre- and...     

Multivariate Spatial Analysis of Climate Change Projections

The goal of this work is to characterize the annual temperature for regional climate models. Of interest for impacts studies, these profiles and the potential change in these profiles are a new way to describe climate change and the inherent uncertainty. To that end, we propose a Bayesian hierarchical spatial model to simultaneously model the temperature profile for the four seasons of the year, current and future. These profiles are then analyzed focusing on understanding how they change over time, how they vary spatially, and how they vary between five different regional climate models. The results show that for temperature, the regional models have different profile shapes depending on a number of factors including spatial location, driving climate model, and regional climate model. This article has supplementary material online.