Transglutaminase 2: a novel autoantigen in canine idiopathic central nervous system inflammatory diseases

Necrotizing meningoencephalitis (NME), necrotizing leukoencephalitis (NLE) and granulomatous meningoencephalomyelitis (GME) are common idiopathic inflammatory central nervous system (CNS) diseases with unknown etiology in dogs. We previously showed that IgG autoantibodies in the cerebrospinal fluid (CSF) of NME cases reacted to unknown brain proteins as well as to glial fibrillary acidic protein (GFAP). In the present report, we evaluated the autoantibodies against transglutaminase2 (TG2) in the canine CNS diseases. CSF samples obtained from dogs with NME (n=19), NLE (n=7), GME (n=11) and miscellaneous CNS diseases (n=12) were subjected. CSFs from 20 healthy dogs were used as controls. Indirect fluorescent antibody test on the canine cerebrum revealed astrocyte-binding IgG in the CSF of NME. After absorption of the CSF with bovine GFAP, the CSF still possessed the reactivity to astrocytes. Double-color staining showed clear colocalization of the autoantibodies and anti-human TG2 rabbit polyclonal IgG. An immunoblot assay against human recombinant TG2 revealed anti-TG2 IgG in the CSF from dogs with NME, NLE and GME. The CSF of canine idiopathic encephalitis cases, notably of NME, tended to show high ELISA OD values against human recombinant TG2 compared to healthy controls. The presence of anti-TG2 autoantibodies in the CSF may contribute to the elucidation of the etiology of canine NME, NLE and GME.     

Autoantibodies against structures of the central nervous system in steroid responsive meningitis-arteriitis in dogs

Steroid-responsive meningitis-arteriitis (SRMA) is a disease of dogs familiar in small animal practice for decades. A combined evaluation of IgA in serum and cerebrospinal fluid (CSF) is an important diagnostic tool. It is suspected that immunpathological mechanisms are involved in the pathogenesis of SRMA because of the marked response to steroids. Excessive production of IgA seems to play a central role and might be caused by an immune reaction to self-antigens of the central nervous system (CNS). To test this hypothesis, we analyzed CSF samples from 55 dogs with SRMA using the western blot method. After blotting canine brain tissue, IgA, IgM and IgG of the CSF samples were tested for their binding to CNS antigens. We also evaluated CSF samples from 45 dogs with other brain diseases, including different encephalitides and intracranial tumors, and from healthy dogs as controls. Positive reactions (mostly IgA) were observed in the CSF samples from dogs with SRMA, different encephalitides and brain tumors (a total of 8% positive samples). The occurrence of autoantibodies against CNS structures was significantly higher in the control group "other brain diseases" than in the SRMA group (p = 0.0135). There was no significant difference in the number of positive samples between dogs with SRMA and the negative control group (healthy dogs, p = 0.1535). Despite the small number of positive samples, only dogs with abnormal findings in the CSF analysis also had autoantibodies in the CSF. There was no significant correlation between the occurrence of autoantibodies and levels of IgA, protein content and cell counts in the cerebrospinal fluid. However, there was a certain trend toward positive reactions in CSF samples with high protein content. The occurrence of autoantibodies in dogs with SRMA thus seems to be an epiphenomenona rather than the cause of the disease.     

Autoantibodies against glial fibrillary acidic protein (GFAP) in cerebrospinal fluids from Pug dogs with necrotizing meningoencephalitis

Cerebrospinal fluids (CSFs) from 9 Pug dogs with necrotizing meningoencephalitis (NME: Pug dog encephalitis) were examined to identify the antigens for anti-astrocyte autoantibodies. Each CSF exhibited a positive reaction to the cytoplasm of cultured canine astrocytes by an indirect fluorescent antibody test. In an immunoblotting analysis on normal canine brain proteins, eight of 9 CSFs showed a common band of 52 kDa, corresponding to glial fibrillary acidic protein (GFAP), and all of 9 CSFs reacted with purified bovine GFAP. From these results, GFAP is one of the common autoantigens in Pug dogs with NME. On the other hand, the reactivity of CSFs to chymotrypsin-digested bovine GFAP fragments were variable among dogs, indicating that the antibodies in the CSFs recognized different epitopes on GFAP.     

Evaluation of risk and clinical outcome of mast cell tumours in pug dogs

Mast cell tumours (MCT) are common in dogs and characterized by diverse biologic behaviour. Our objective was to evaluate the risk of MCT in pugs and to describe the clinical behaviour of MCT in this breed. Data obtained from the Veterinary Medicine Database demonstrate significantly increased frequency of MCT in pugs compared with other dogs (OR = 2.28, 95% CI = 1.81–2.86). The medical records for 25 purebred pugs with a histologic diagnosis of MCT were reviewed. Multiple cutaneous tumours were documented in 14 (56 %) of the dogs. Histologic review of 64 tumours from these dogs confirmed that most tumours (94%) were low to intermediate grade. Sixty‐four per cent of these dogs are still living, while only three dogs (12%) have died due to mast cell disease. A median survival time has not been reached. The median follow‐up time is 660 days from the diagnosis of the first MCT. We conclude that MCT in pugs are relatively benign, despite the presence of multiple cutaneous tumours in most cases. Multiple tumours in breeds with predisposition to MCT may indicate separate primaries rather than advanced stage disease.     

Impaired expression of excitatory amino acid transporter 2 (EAAT2) and glutamate homeostasis in canine necrotizing meningoencephalitis

To clarify the involvement of excitatory and inhibitory amino acids in canine necrotizing meningoencephalitis (NME), glutamate, aspartate, taurine and gamma-aminobutylic acid (GABA) were determined in the cerebrospinal fluids (CSF) from eight NME cases and ten healthy controls. NME dogs exhibited significantly higher concentrations of glutamate and aspartate than those in controls (p<0.001 and p<0.001, respectively), while there was no difference in taurine or GABA between the two groups. When fetal canine astrocytes were cultured for 24 hr in the presence of NME-CSF, supernatant concentrations of glutamate, aspartate and taurine were significantly elevated. Simultaneously, expression of excitatory amino acid transporter 2 (EAAT2) mRNA was significantly reduced in the astrocytes without change in EAAT1 mRNA. Hence, reduced expression of EAAT2 and impaired glutamate homeostasis may contribute to the pathogenesis of NME.     

Prevalence of autoantibody in cerebrospinal fluids from dogs with various CNS diseases

To examine the prevalence of autoantibody in canine cerebrospinal fluids (CSFs), CSFs were collected from 14 healthy controls and 88 clinical cases with various diseases in the central nervous system (CNS), and were analyzed by an indirect fluorescence antibody test on frozen sections of the cerebrum from normal Beagle dogs. An anti-astrocyte autoantibody was detected in 31 clinical cases with titers ranging from 1:1 to >/=1:100. All tested cases with necrotizing meningoencephalitis (NME: n=22) and granulomatous meningoencephalitis (GME: n=3) possessed the anti-astrocyte autoantibody, while the autoantibody was negative in most cases with other inflammatory CNS diseases. The autoantibody was also detected in 4 of 12 cases with brain tumors. Hence, examination of the autoantibody in the canine CFS would be significant for diagnosing NME and/or GME, as well as for understanding peritumoral events in cases with brain tumors.     

Beta-2-microglobulin levels in the cerebrospinal fluid of normal dogs and dogs with neurological disease

BACKGROUND: Cerebrospinal fluid (CSF) analysis is the basis for establishing a diagnosis of central nervous system (CNS) inflammation. However, the information provided by routine CSF analysis is limited. Determination of CSF beta-2-microglobulin (beta2m) concentration has been used diagnostically in humans to identify inflammatory CNS disease; we hypothesized that it may have similar value in dogs. OBJECTIVES: The objective of this study was to measure (beta2m concentration in the CSF of clinically healthy dogs and compare the values to those observed in dogs with inflammatory CNS disease and intervertebral disc disease (IVDD). METHODS: CSF was collected from 10 clinically healthy laboratory dogs and 11 dogs each with inflammatory CNS disease and IVDD. Routine CSF analysis was performed, and (beta2m concentration was measured by ELISA. CSF (beta2m concentration and CSF:serum (beta2m ratio were compared between groups by ANOVA. Linear relationships between CSF total nucleated cell count (TNCC), RBC count, total protein concentration, and (beta2m concentration were assessed by regression analysis. RESULTS: The mean (+/- SD) CSF (beta2m concentration in clinically healthy dogs was 0.36 (+/- 0.05 microg/mL (cisternal) and 0.40 (+/- 0.07 microg/mL (lumbar). Median CSF (beta2m concentration in dogs with IVDD (0.46 microg/mL) and inflammatory CNS disease (0.85 microg/mL) differed from that of controls (0.36 microg/mL; P=.002). The concentration also differed between the 2 disease groups (P=.01). Five dogs with inflammatory CNS disease had CSF:serum (beta2m ratios >1. A correlation was identified between TNCC and (beta2m concentration (r=0.69, P=.0003). CONCLUSIONS: CSF (beta2m concentration is higher in dogs with IVDD and inflammatory CNS disease, with highest values seen with inflammatory disease. This may be attributed in part to the correlation between CSF (beta2m concentration and TNCC, but also may reflect intrathecal immune activation.     

Total protein, albumin quota, and electrophoretic patterns in cerebrospinal fluid of dogs with central nervous system disorders

Cerebrospinal fluid was analyzed for total protein, albumin quota, and electrophoretic patterns of albumin and alpha-, beta-, and gamma-globulins in 10 healthy dogs and 35 dogs with CNS disorders. Values obtained in healthy dogs were used to establish control data. Samples also were collected from dogs with neurologic diseases that were classified according to clinical and pathologic diagnosis as inflammation, neoplasm, and spinal cord compression. The albumin quota and total CSF albumin values were used as indicators of blood-brain barrier disturbance. Four patterns were observed on agarose electrophoresis that included intrathecal immunoglobulin production, intrathecal immunoglobulin production combined with blood-brain barrier disturbance, blood-brain barrier disturbance, and unaltered CSF. These patterns correlated with the observed clinical and pathologic conditions. Seemingly, agarose electrophoresis of CSF is a simple and reliable technique that aids in the diagnosis of CNS disorders of dogs.     

Epidemiology of necrotizing meningoencephalitis in Pug dogs

BACKGROUND: Although the histopathologic features of necrotizing meningoencephalitis (NME) have been described previously, little information is available concerning the signalment, geographic distribution, seasonal onset, treatment, and survival of affected dogs. ANIMALS: Sixty Pugs with NME and 14 contemporaneous control Pugs with other intracranial diseases (non-NME group). METHODS: Pugs that were euthanized or died because of intracranial disease were prospectively obtained. All dogs had necropsy, histopathology, and testing for various infectious diseases and were subsequently divided into NME and non-NME groups. Signalment, geographic distribution, seasonal onset, treatment, and survival were compared between groups. RESULTS: In Pugs with NME, median age at onset of clinical signs was 18 months (range, 4-113 months). A greater proportion of female dogs were present in the NME group (40/60) compared with the control group (6/14). Pugs with NME had a significantly lower mean weight (7.81 kg) than control Pugs (9.79 kg) (P= .012). Mean survival in Pugs with NME was 93 days (range, 1-680 days), with dogs receiving any form of treatment living significantly longer than those that were not treated (P= .003). Anticonvulsive drugs were the only treatment significantly associated with longer survival (P= .003). CONCLUSIONS AND CLINICAL IMPORTANCE: NME appears to be a common cause of intracranial signs in Pugs, based on the high proportion of NME dogs reported in this population. Pugs with NME are most commonly young adult female dogs. Although further investigation is needed to determine the optimal treatment of NME, anticonvulsive drugs appear to beneficially affect duration of survival.     

Comparison of the prevalence of enteric viruses in healthy dogs and those with acute haemorrhagic diarrhoea by electron microscopy

Objectives: To evaluate prevalence of enteric viruses in healthy dogs and to compare it with prevalences in dogs with acute haemorrhagic diarrhoea. Methods: Faecal samples were collected from 200 healthy dogs and examined by electron microscopy for presence of viral particles. Data were compared with viral prevalences that had been determined retrospectively by electron microscopy for 936 dogs with acute haemorrhagic diarrhoea. Results: There were significantly more negative faecal samples among the healthy dogs (82.0 per cent) compared with 55.8 per cent in dogs with acute haemorrhagic diarrhoea (P<0.001). With a prevalence of 17.5 per cent, significantly more healthy dogs were shedding coronavirus compared with 11.6 per cent in dogs with acute haemorrhagic diarrhoea (P=0.034). Parvovirus was only detected in one healthy dog (0.5 per cent), thus with a prevalence that was significantly lower than 16.0 per cent detected in the dogs with acute haemorrhagic diarrhoea (P<0.001). Paramyxovirus was not found in any of the healthy dogs but was found in 9.3 per cent of dogs with acute haemorrhagic diarrhoea (P<0.001). Clinical Significance: Results suggest that shedding of parvovirus and paramyxovirus is strongly associated with acute haemorrhagic diarrhoea. However, coronavirus seems to be even more prevalent among healthy dogs, raising the need for further studies to investigate the strain-associated pathogenicity of this virus.     

Determination of immunoglobulin A concentrations in the serum and cerebrospinal fluid of dogs: an estimation of its diagnostic value in canine steroid-responsive meningitis-arteritis

Previous studies on canine steroid-responsive meningitis-arteritis (SRMA) suggested that elevation of immunoglobulin A (IgA) concentrations in both serum and cerebrospinal fluid (CSF) is specific for SRMA throughout the different disease stages. Recent studies however have raised concerns about the value of this test. The purpose of this study was to investigate the diagnostic value of IgA concentration testing in paired CSF and serum samples. IgA concentrations of 525 paired canine CSF and serum samples were evaluated. Samples were obtained from dogs with SRMA (n=311) and dogs with miscellaneous conditions (n=214) such as other central nervous system (CNS) inflammatory diseases (n=34), CNS tumours (n=46), idiopathic epilepsy (n=42), intervertebral disc disease (n=46) and non-CNS diseases (n=46). Serum IgA concentrations were significantly higher in dogs with untreated SRMA compared to those with other diseases. IgA CSF concentrations were significantly higher in dogs with SRMA compared to other disease categories, with the exception of inflammatory CNS disease. The sensitivity for IgA concentrations in serum and CSF was 91% with a specificity of 78%. Analysis of 525 paired samples confirmed that IgA concentrations were higher in dogs with SRMA. Calculation of the diagnostic value of IgA concentration confirmed that the test is highly sensitive for SRMA. Testing paired CSF and serum samples for IgA is still recommended for the diagnosis of suspected cases of SRMA.     

Canine neurological diseases in a referral hospital population between 1989 and 2000 in Switzerland

OBJECTIVES: To merge clinical information from partly overlapping medical record databases of the Small Animal Teaching Hospital of the Vetsuisse Faculty, University of Berne. To describe the frequencies and localisations of neurological diseases in dogs, as well as their age, gender, breed and geographical distributions. METHODS: In this retrospective study, a new database, with specific variables and a diagnosis key list 'VITAMIN D', was created and defined. A total of 4497 dogs (average of 375 per year) with a well-documented neurological disease were included in the study. A key list for the diagnoses was developed and applied to either the presumptive or the clinical and neurohistopathological diagnosis, with a serial number, a code for localisation and a code for differential diagnoses. RESULTS: Approximately 1159 dogs (26 per cent) had a neurohistopathological diagnosis confirmed, 1431 (32 per cent) had a clinical diagnosis confirmed and 1491 (33 per cent) had a presumptive diagnosis. The most frequent breeds were mixed-breed dogs (577 of 4497, 13 per cent), followed by German shepherd dogs (466 of 4497, 10 per cent). The most common localisations were the forebrain (908 of 4497, 20 per cent) and the spinal cord at the thoracolumbar area (840 of 4497, 19 per cent). Most dogs were diagnosed with degenerative diseases (38 per cent), followed by inflammatory/infectious diseases (14 per cent). The highest number of submissions originated from geographic regions around the referral hospital and from regions with higher human population densities. CLINICAL SIGNIFICANCE: By defining closed-list fields and allocating all data to the corresponding fields, a standardised database that can be used for further studies was generated. The analysis of this study gives examples of the possible uses of a standardised database.     

Cerebrospinal Fluid PCR and Antibody Concentrations against Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato in Dogs with Neurological Signs

Background: The tick-borne bacteria Borrelia burgdorferi sensu lato (sl) and Anaplasma phagocytophilum have been suspected to cause neurological signs in dogs. Diagnosis often has been made based on positive antibody titers in serum of dogs with neurological signs, but a high seroprevalence in dogs in at-risk populations makes diagnosis difficult.
Objective: To determine if the neurological signs in dogs examined were caused by any of these bacteria.
Animals: Fifty-four dogs presented to a board-certified neurologist.
Methods: Prospective study. We divided dogs into 2 groups: those with inflammatory diseases of the central nervous system (CNS) and those with neurological signs from other diseases. Blood and cerebrospinal fluid (CSF) from all dogs were analyzed.
Results: Dogs with inflammatory CNS diseases showed no serum antibodies against any of the agents. Among dogs with neurological signs from other diseases, 10.3% had serum antibodies for B. burgdorferi sl and 20.5% for A. phagocytophilum . All blood samples analyzed for bacterial deoxyribonucleic acid (DNA) and all CSF analyzed for antibodies and bacterial DNA for the 2 agents were negative.
Conclusions and Clinical Importance: Based on this study, these bacteria are unlikely causes of neurologic disease in dogs and the presence of serum antibodies alone does not document or establish a definitive diagnosis of CNS disease caused by these organisms. Dogs that have neurologic disease and corresponding serum antibodies against these agents should have additional tests performed to assess for other potential etiologies of the signs.     

Evaluation of Brain Tissue or Cerebrospinal Fluid with Broadly Reactive Polymerase Chain Reaction for Ehrlichia,Anaplasma, Spotted Fever Group Rickettsia,Bartonella, and Borrelia Species in Canine Neurological Diseases (109 Cases)

Background: Vector‐transmitted microorganisms in the genera Ehrlichia, Anaplasma, Rickettsia, Bartonella, and Borrelia are commonly suspected in dogs with meningoencephalomyelitis (MEM), but the prevalence of these pathogens in brain tissue and cerebrospinal fluid (CSF) of dogs with MEM is unknown. Hypothesis/Objectives: To determine if DNA from these genera is present in brain tissue and CSF of dogs with MEM, including those with meningoencephalitis of unknown etiology (MUE) and histopathologically confirmed cases of granulomatous (GME) and necrotizing meningoencephalomyelitis (NME). Animals: Hundred and nine dogs examined for neurological signs at 3 university referral hospitals. Methods: Brain tissue and CSF were collected prospectively from dogs with neurological disease and evaluated by broadly reactive polymerase chain reaction (PCR) for Ehrlichia, Anaplasma, Spotted Fever Group Rickettsia, Bartonella, and Borrelia species. Medical records were evaluated retrospectively to identify MEM and control cases. Results: Seventy‐five cases of MUE, GME, or NME, including brain tissue from 31 and CSF from 44 cases, were evaluated. Brain tissue from 4 cases and inflammatory CSF from 30 cases with infectious, neoplastic, compressive, vascular, or malformative disease were evaluated as controls. Pathogen nucleic acids were detected in 1 of 109 cases evaluated. Specifically, Bartonella vinsonii subsp. berkhoffii DNA was amplified from 1/6 dogs with histopathologically confirmed GME. Conclusion and Clinical Importance: The results of this investigation suggest that microorganisms in the genera Ehrlichia, Anaplasma, Rickettsia, and Borrelia are unlikely to be directly associated with canine MEM in the geographic regions evaluated. The role of Bartonella in the pathogenesis of GME warrants further investigation.     

Anticardiolipin antibodies in healthy and diseased dogs

The concentrations of anticardiolipin immunoglobulin G (IgG) were measured in 134 healthy dogs and 63 diseased dogs by an elisa. The mean (sd) concentration in the healthy dogs was 5.40 (2.60) IgG phospholipid (gpl) units, and concentrations greater than 11 gpl were considered as above the normal range. On this basis, 30 (47.6 per cent) of the diseased dogs were within the normal range, with a mean of 5.45 (3.07) gpl and the other 33 had levels above the normal range (P<0.001); 19 of them had a mean level of 22.2 (5.66) gpl, 10 had a mean level of 49.1 (11.2) gpl, and four had a mean level of 85.8 (9.64) gpl. Levels above the normal range were more frequent in females (59.4 per cent) than in males (45.1 per cent), but were higher in males (45.5 [34.71] v 42.91 [22.0] gpl). In addition, they were more frequent and higher in older dogs (66.7 per cent, 40.4 [24.0] gpl) than in younger dogs (33.3 per cent, 33.5 [21.4] gpl).     

Survey of thyroglobulin autoantibodies in dogs

An enzyme-linked immunosorbent assay was used to detect autoantibodies to thyroglobulin in dogs with and without clinical evidence of thyroid disease. Autoantibodies were found in 59% of 34 clinically hypothyroid dogs, 43% of 65 dogs with nonthyroidal endocrine diseases, 47% of 64 healthy dogs closely related to antibody-positive canine hospital patients, and 13% of 1,057 canine hospital patients without endocrine disorders. Dogs with bacterial skin disease and alopecia of unknown causes had an increased prevalence of autoantibodies compared with the prevalence of autoantibodies in healthy dogs and dogs with other diseases. Three breeds of dogs, Great Danes, Irish Setters, and Old English Sheepdogs, had an increased occurrence of autoantibodies compared with that in other breeds and dogs of mixed breeding. A familial tendency to thyroid autoimmunity was demonstrated in a group of Great Dane dogs. The occurrence of autoantibodies was not influenced by age or sex. Thyroid function, as assessed by total thyroxine estimation, was depressed in hospitalized dogs compared with the thyroid function in healthy dogs, irrespective of thyroglobulin-antibody status. Two of 11 autoantibody-positive dogs monitored for an 18-month period developed low thyroxine concentration and depressed thyroid responsiveness to exogeneous thyrotropin stimulation.     

Detection of oligoclonal bands in cerebrospinal fluid from German Shepherd dogs with degenerative myelopathy by isoelectric focusing and immunofixation

BACKGROUND: Detection of intrathecal IgG synthesis is important in evaluating inflammatory diseases in the central nervous system. Isoelectric focusing (IEF) is currently the most sensitive method to demonstrate intrathecal IgG synthesis and may have diagnostic value for German Shepherd degenerative myelopathy (GSDM). OBJECTIVE: The objective of this study was to adapt a modified IEF and immunofixation method for the detection of oligoclonal bands in cerebrospinal fluid (CSF) from dogs with GSDM. METHODS: Serum and lumbar CSF samples were collected from 6 German Shepherd dogs clinically diagnosed with GSDM. Samples were also collected from 6 clinically healthy dogs for comparison. The concentration of IgG was measured by quantitative ELISA and the concentration of total protein was measured by the Bradford protein assay. The presence of oligoclonal bands was evaluated by use of modified IEF followed by immunofixation. RESULTS: The concentrations of total protein and IgG, and the IgG/total protein ratio in CSF samples, were not significantly different between GSDM patients and control dogs. Four GSDM patients had oligoclonal bands in their CSF based on IEF-immunofixation. No oligoclonal bands were found in CSF from control dogs. CONCLUSION: The results suggest that the detection of oligoclonal bands by IEF-immunofixation may have diagnostic value for GSDM, and support the idea that humoral immune responses may play a role in the pathogenesis of GSDM.     

Osmotic fragility of erythrocytes in clinically normal dogs and dogs infected with parasites

The osmotic fragility of the erythrocytes was measured in blood samples collected from randomly selected healthy and infected dogs at a dogs' rescue shelter. The dogs were classified into six groups on the basis of the final diagnoses from clinical, post mortem and laboratory findings. The minimum (less than 5 per cent) and maximum (more than 90 per cent) haemolysis of the erythrocytes of the clinically normal dogs (group 1), occurred in 0·60 per cent and 0·30 per cent solutions of sodium chloride (NaCI). For the non-anaemic hookworm-infected dogs (group 2a) the respective values were 0·8 per cent and 0·4 per cent NaCl, and for the anaemic hookworm-infected dogs (group 2b) they were 0·85 per cent and 0·5 per cent NaCl, respectively. The erythrocytes from dogs with Babesia canis (group 3), concurrent hookworm and B canis (group 4) and Ehrlichia canis infections (group 5) had minimum haemolysis in 0·75 per cent NaCl and maximum haemolysis at between 0·20 per cent and 0·35 per cent NaCI solutions. The derivative fragiligrams for groups 2a, 2b, 3 and 4 were shifted to the left, whereas the fragiligram for group 5 was similar to that for the clinically normal dogs (group 1). The left shift for the hookworm-infected dogs was due to the increased osmotic fragility of a minor sub-population of the erythrocytes, but for the dogs, infected with B canis major sub-populations of the erythrocytes had an increased osmotic fragility.     

Proteome analysis of cerebrospinal fluid in healthy beagles and canine encephalitis

We performed proteomics analysis of the cerebrospinal fluid (CSF) of healthy dogs and dogs with meningoencephalitis of unknown etiology (MUE). By comparing two-dimensional electrophoreses (2DE), an upregulated spot was found in MUE dogs. This protein was identified as a neuron-specific enolase (NSE) by analysis with MALDI-TOF mass spectrometry. In comparing dot blots using an antibody against NSE, the NSE levels in the CSF of MUE dogs was significantly higher than that of the controls. NSE is a diagnostic marker of neuroendocrine tumors, brain injury and spinal cord trauma in humans. It seems that the NSE concentration in the CSF is increased by cellular destruction in canine encephalitis. Though elevation of NSE may not be specific in canine encephalitis because the NSE level was increased in other CNS diseases, further study including measurement with serum is necessary.     

Suspected side effects of doxycycline use in dogs - a retrospective study of 386 cases

This study investigated doxycycline-related side effects in a large population of dogs. Data from 386 dogs that had received doxycycline for the treatment of various infectious diseases were analysed retrospectively. Potential side effects that developed during treatment were documented, and correlations with signalment, dose, duration of treatment, frequency of application, doxycycline preparation and use of additional drugs were investigated. Vomiting was reported in 18.3 per cent of dogs, 7.0 per cent developed diarrhoea and 2.5 per cent developed anorexia. While being treated with doxycycline, 39.4 per cent of dogs showed an increase in alanine aminotransferase (ALT) activity and 36.4 per cent showed an increase in alkaline phosphatase (ALP) activity. There was a dose-related risk of an increase in ALP activity (P=0.011, odds ratio [OR]=1.27, 95 per cent confidence interval [CI] 1.06 to 1.53), and older dogs treated with doxycycline were more likely to develop an increase in ALT activity (P=0.038, OR=1.23, 95 per cent CI 1.01 to 1.50) and vomiting (P=0.017, OR=1.11, 95 per cent CI 1.02 to 1.21).