Thrombocytopenia In Dogs Research Articles

Plasma concentration of thrombopoietin in dogs with immune thrombocytopenia.

Immune thrombocytopenia (ITP) is a common cause of severe thrombocytopenia in dogs. The pathogenesis of nonassociative, primary ITP (pITP) appears complex, with ill-defined thrombopoietic response. Develop an immunoassay to measure plasma canine thrombopoietin (TPO) concentration and characterize TPO concentrations in dogs with pITP. Forty-one healthy dogs, 8 dogs in an induced ITP model (3 control, 5 ITP), and 58 pITP dogs. Recombinant canine TPO (rcTPO) was purchased and its identity confirmed by mass spectrometry. Monoclonal antibodies were raised to rcTPO and used to configure a sandwich ELISA using streptavidin-biotin detection. Assay performance, coefficients of variability, and healthy dog plasma TPO reference interval (RI) were determined, followed by assay of ITP samples. Assay dynamic range was 15 pg/mL (lower limit of detection) to 1000 pg/mL TPO, with limit of quantitation of 62 pg/mL. Plasma TPO RI was 0 to 158 pg/mL, with plasma TPO <62 pg/mL for 35/41 healthy dogs. All dogs with induced ITP developed marked increases in plasma TPO concentration. Peak values ranged from 515 to >6000 pg/mL. In contrast, only 2/58 pITP dogs had TPO values above RI. Plasma TPO concentration is paradoxically low at diagnosis for most dogs with pITP. This finding suggests that ineffective thrombopoiesis contributes to thrombocytopenia in pITP dogs and supports evaluating TPO receptor agonist treatment as used for pITP in humans. The TPO assay provides a new tool to study thrombopoiesis in pITP and other thrombocytopenic syndromes in dogs.

ACVIM consensus statement on the treatment of immune thrombocytopenia in dogs and cats.

Management of immune thrombocytopenia (ITP) in dogs and cats is evolving, but there are no evidence-based guidelines to assist clinicians with treatment decisions. Likewise, the overall goals for treatment of ITP have not been established. Immunosuppressive doses of glucocorticoids are the first line treatment, but optimal treatment regimens beyond glucocorticoids remain uncertain. Additional options include secondary immunosuppressive drugs such as azathioprine, modified cyclosporine, and mycophenolate mofetil, usually selected based on clinician preference. Vincristine, human IV immunoglobulin (hIVIg), and transfusion of platelet or red blood cell-containing products are often used in more severe cases. Splenectomy and thrombopoietin receptor agonists are usually reserved for refractory cases, but when and in which patient these modalities should be employed is under debate. To develop evidence-based guidelines for individualized treatment of ITP patients, we asked 20 Population Intervention Comparison Outcome (PICO) format questions. These were addressed by 17 evidence evaluators using a literature pool of 288 articles identified by a structured search strategy. Evidence evaluators, using panel-designed templates and data extraction tools, summarized evidence and created guideline recommendations. These were integrated by treatment domain chairs and then refined by iterative Delphi survey review to reach consensus on the final guidelines. In addition, 19 non-PICO questions covering scenarios in which evidence was lacking or of low quality were answered by expert opinion using iterative Delphi surveys with panelist integration and refinement. Commentary was solicited from multiple relevant professional organizations before finalizing the consensus. The rigorous consensus process identified few comparative treatment studies, highlighting many areas of ITP treatment requiring additional studies. This statement is a companion manuscript to the ACVIM Consensus Statement on the Diagnosis of Immune Thrombocytopenia in Dogs and Cats.

ACVIM consensus statement on the diagnosis of immune thrombocytopenia in dogs and cats.

Immune thrombocytopenia (ITP) is the most common acquired primary hemostatic disorder in dogs. Immune thrombocytopenia less commonly affects cats but is an important cause of mortality and treatment-associated morbidity in both species. Immune thrombocytopenia remains a diagnosis of exclusion for which diagnostic guidelines are lacking. Primary, or non-associative, ITP refers to autoimmune platelet destruction. Secondary, or associative, ITP arises in response to an underlying disease trigger. However, evidence for which comorbidities serve as ITP triggers has not been systematically evaluated. To identify key diagnostic steps for ITP and important comorbidities associated with secondary ITP, we developed 12 Population Evaluation/Exposure Comparison Outcome (PECO) format questions. These questions were addressed by evidence evaluators utilizing a literature pool of 287 articles identified by the panelists using a structured search strategy. Evidence evaluators, using panel-designed templates and data extraction tools, summarized evidence and created guideline recommendations that then were integrated by diagnosis and comorbidity domain chairs. The revised PECO responses underwent a Delphi survey process to reach consensus on final guidelines. A combination of panel expertise and PECO responses were employed to develop algorithms for diagnosis of ITP in dogs and cats, which also underwent 4 iterations of Delphi review. Comorbidity evidence evaluators employed an integrated measure of evidence (IME) tool to determine evidence quality for each comorbidity; IME values combined with evidence summaries for each comorbidity were integrated to develop ITP screening recommendations, which also were subjected to Delphi review. Commentary was solicited from multiple relevant professional organizations before finalizing the consensus. The final consensus statement provides clinical guidelines for the diagnosis of, and underlying disease screening for, ITP in dogs and cats. The systematic consensus process identified numerous knowledge gaps that should guide future studies. This statement is a companion manuscript to the ACVIM Consensus Statement on the Treatment of Immune Thrombocytopenia.

Utility of immature platelet fraction in the Sysmex XN-1000V for the differential diagnosis of central and peripheral thrombocytopenia in dogs and cats.

The immature platelet fraction (IPF), a parameter obtained by the Sysmex XN-1000V analyzer, is used in humans to differentiate between central (CEN) and peripheral (PER) thrombocytopenia (TP) but has not been evaluated in small animals. Compare IPF between healthy, clinical non-TP and TP dogs and cats, study IPF in different causes of TP in dogs and cats and, establish IPF reference intervals (RIs), and study the effect of age and sex on IPF in healthy dogs and cats. A total of 3281 dogs and 726 cats. Retrospective review of medical records. Animals were classified as nonthrombocytopenic (healthy group and group of clinical patients without TP [NTP]) or TP. These latter animals were subclassified as pseudothrombocytopenia (PSE), CEN and PER, based on evaluation of platelet clumps, estimated platelet count in blood smears and final diagnosis. Blood samples were evaluated using a Sysmex XN-1000V with a specific platelet channel (PLT-F). The IPF was significantly different between each subtype of TP in both species. Immature platelet fractions <6.9% in dogs or 13.6% in cats, once PSE has been eliminated by review of blood smears, are indicative of CEN. Reference intervals for IPF were 0.5%-8% in healthy dogs and 1%-40.3% in healthy cats. We determined that IPF can differentiate between CEN and PER in dogs and cats, guiding additional testing and avoiding more invasive procedures (bone marrow sampling). A blood smear always should be evaluated to rule out platelet clumping.

Romiplostim for treatment of thrombocytopenia in dogs: A retrospective assessment and clinical outcomes.

Romiplostim, a thrombopoietin analog, is commonly used to treat immune-mediated thrombocytopenia (ITP) in humans, but its use in dogs remains limited. Evaluate the effects and adverse events of romiplostim administration in dogs with thrombocytopenia caused by various underlying diseases. Forty-two client-owned dogs with naturally occurring thrombocytopenia at 2 referral animal hospitals. Retrospective, multi-institutional analysis to evaluate the outcomes of romiplostim treatment in dogs. Among the dogs treated with romiplostim, 27 experienced an increase in platelet count and 26 maintained a platelet count within the reference range. Platelet count improvement was observed in various conditions: primary ITP (90%, n = 18/20), pancytopenia of unknown etiology (42.9%, n = 3/7), chemotherapy-induced thrombocytopenia (50%, n = 3/6), babesiosis (100%, n = 1/1), radiotherapy-induced thrombocytopenia (0%, n = 0/1), and disseminated intravascular coagulopathy (33.3%, n = 2/6). The median time for platelet recovery (>50 000/μL) after romiplostim administration was 4 days, and the median time for platelet count normalization was 7 days. Median hospitalization time for the improvement group (I) was 5 days. The survival-to-discharge rates were 85%, 40%, and 28.6% for dogs with primary ITP, secondary thrombocytopenia, and thrombocytopenia of unknown etiology, respectively. Romiplostim is a well-tolerated and promising treatment for primary ITP in dogs, suggesting its potential as a valuable therapeutic option for dogs with thrombocytopenia caused by various underlying conditions. These findings emphasize the need for further research to optimize romiplostim dosing and understand its role in treating secondary thrombocytopenia and pancytopenia of unknown etiology.

A prospective cohort study to identify clinical diagnostic and prognostic markers of primary immune thrombocytopenia in dogs.

Primary immune thrombocytopenia (pITP) in dogs presents a diagnostic challenge, and clinical markers of severity are lacking. Identify clinicopathologic features that differentiate pITP from secondary ITP (sITP) and markers related to bleeding severity, transfusion, and survival of dogs with pITP. Ninety-eight thrombocytopenic dogs (58 pITP and 40 sITP). Client-owned dogs with platelet counts <50 000/μL were enrolled in a prospective, multi-institution cohort study. History and treatment information, through a maximum of 7 days, was recorded on standard data forms. Bleeding severity was scored daily using a bleeding assessment tool (DOGiBAT). At-admission blood samples were collected for CBC, biochemistry, C-reactive protein concentration, and coagulation panels, and to measure platelet surface-associated immunoglobulin G (PSAIg) and expression of platelet membrane proteins and phospholipids. Dogs with evidence of coincident disease were classified as sITP. No definitive pITP diagnostic test was found. However, pITP cases were characterized by lower platelet counts, D dimer concentrations, and platelet membrane protein expression than sITP cases. Differentiation between pITP and sITP was further enhanced using logistic regression modeling combining patient sex, coagulation profile, platelet count, D dimer, and PSAIg. A second model of pITP severity indicated that low hematocrit and high BUN concentration were associated with non-survival. Low hematocrit at admission, but not platelet count or DOGiBAT score, was associated with transfusion. Pending validation studies, models constructed from at-admission clinicopathologic findings may improve differentiation of pITP from sITP and identify the most severe pITP cases at the time of presentation.

Causes of thrombocytopenia in dogs in the United Kingdom: A retrospective study of 762 cases.

Thrombocytopenia is a common laboratory abnormality in dogs, and numerous diseases have been associated with its development. Estimates for the sensitivity and specificity of the degree of reduction of platelet concentration for the diagnosis of primary immune-mediated thrombocytopenia (pITP) have not been reported. To report the prevalence of different causes of thrombocytopenia in dogs in the United Kingdom and to investigate the utility of platelet concentration to differentiate causes of thrombocytopenia. Medical records of 762 dogs with thrombocytopenia presented to seven referral hospitals from January 2017 to December 2018 were retrospectively reviewed. Cases were assigned into the following categories: pITP, infectious diseases, neoplasia, inflammatory/other immune-mediated disorders and miscellaneous causes. The prevalence of the different categories was estimated, and platelet concentrations were compared. Receiver-operating characteristic (ROC) curves were used to investigate the utility of platelet concentration to differentiate between causes of thrombocytopenia. The most common disease category associated with thrombocytopenia was neoplasia (27.3%), followed by miscellaneous causes (26.9%), pITP (18.8%), inflammatory/immune-mediated disorders (14.4%) and infectious diseases (12.6%). Dogs with pITP had significantly lower platelet concentrations (median 8×109 /L, range: 0-70×109 /L) than dogs in the other four categories. Platelet concentration was useful for distinguishing pITP from other causes of thrombocytopenia (area under ROC curve=0.89, 95% confidence interval 0.87, 0.92), with a platelet concentration ≤12×109 /L being 60% sensitive and 90% specific. Severe thrombocytopenia was highly specific for a diagnosis of pITP, which was more prevalent in this UK population of thrombocytopenic dogs compared with previous epidemiological studies. Conversely, the proportion of dogs with infectious diseases was lower than in previous reports from other locations.

Splenectomy in the management of primary immune-mediated hemolytic anemia and primary immune-mediated thrombocytopenia in dogs.

BackgroundCurrent reports about the use of splenectomy for the management of immune‐mediated hemolytic anemia (IMHA) or immune‐mediated thrombocytopenia (ITP) or both in dogs are limited.ObjectivesTo retrospectively describe the use of splenectomy as part of the management for IMHA, ITP, and concurrent IMHA and severe thrombocytopenia (CIST) in dogs. It was hypothesized that splenectomy would be beneficial in allowing for reduction of dose of immunosuppressive drugs or discontinuation in 1 or more of these groups.AnimalsSeventeen client‐owned dogs (7 with IMHA, 7 with ITP, and 3 with CIST) were identified across 7 UK‐based referral hospitals from a study period of 2005 to 2016.MethodsData were collected retrospectively via questionnaires and included information about diagnosis, management and treatment response before and after splenectomy. Based on clinical outcome, treatment with splenectomy as part of the management protocol was classified as either successful or unsuccessful.ResultsSix of 7 dogs with ITP were managed successfully with splenectomy as part of their management protocol (3 complete and 3 partial responses), although 1 subsequently developed suspected IMHA. Of the 7 dogs with IMHA, splenectomy was part of a successful management protocol in 4 dogs (2 complete and 2 partial responses). In the CIST group, 1 case (1/3) responded completely to management with splenectomy as part of the management protocol.Conclusions and Clinical ImportanceSplenectomy was considered successful and well tolerated in most cases of isolated ITP. Whether there is a benefit of splenectomy in cases of IMHA and CIST could not be determined in the current study.

Severe thrombocytopenia due to subinvolution of placental sites in a Maltese terrier

AbstractA 2‐year‐6‐month‐old, primiparous, female, entire Maltese terrier presented 4 weeks after whelping with an acute history of lethargy and vulval haemorrhage. It was found to be anaemic and severely thrombocytopenic, which raised the concern about thrombocytopenia being the primary cause of the profuse haemorrhage. The dog received a packed red blood cell transfusion that resulted in the improvement of the anaemia. The platelet count normalised without a specific intervention. Abdominal ultrasound revealed changes consistent with subinvolution of placental sites. An ovariohysterectomy was performed and the dog recovered uneventfully. This case has shown unusually severe thrombocytopenia secondary to haemorrhage, which should be considered a differential diagnosis for severe thrombocytopenia in dogs.

First report on molecular characteristics and risk factor analysis of Ehrlichia canis in dogs in Khon Kaen, Thailand.

Background and Aim:Ehrlichia canis is a well-known cause of both anemia and thrombocytopenia in dogs. There are insufficient epidemiological data on this blood parasite in Thailand and the association of infections with hematological abnormalities. This study aimed to analyze the molecular characteristics and to identify E. canis as well as the risk factors associated with E. canis infection in dogs in Khon Kaen, Thailand.Materials and Methods:Blood samples from 126 dogs that visited animal clinics were subjected to molecular detection using nested polymerase chain reaction for E. canis 16S rRNA gene. The risk factors and hematological profiles associated with the infection were analyzed using the logistic regression test in program SPSS version 19.Results:Forty-one dogs were infected, indicating a 32.5% molecular infection rate of E. canis. The factors significantly associated with E. canis infection include animal housing status, low packed cell volume, low red blood cell count, and low platelets (p<0.05). Ten positive samples were amplified, sequenced, and phylogenetically analyzed. Sequence and phylogenetic analysis confirmed the current ten samples as E. canis compared with reference sequences in GenBank, using the BLAST program hosted by NCBI, which showed 99.74-100% similarity.Conclusion:This study provided the first data of infection rate of E. canis using nested PCR and molecular characteristics of E. canis in randomly selected domestic dogs in Khon Kaen, Thailand.

Lyophilized platelets versus cryopreserved platelets for management of bleeding in thrombocytopenic dogs: A multicenter randomized clinical trial

BackgroundThrombocytopenia in dogs is common in critical care medicine, but availability of fresh platelet concentrates in veterinary medicine can be limiting. Lyophilized platelets have long shelf‐lives and can be easily transported, stored, and administered in various settings.ObjectiveTo evaluate the efficacy and safety of a novel trehalose‐stabilized canine lyophilized platelet product in thrombocytopenic dogs with clinically‐evident bleeding.AnimalsEighty‐eight dogs with platelet counts <50 × 103/μL and a standardized bleeding assessment tool (DOGiBAT) score ≥2.MethodsMulticenter, randomized, non‐blinded, non‐inferiority clinical trial comparing dimethyl sulfoxide (DMSO)‐stabilized cryopreserved platelet concentrates (CPP) with trehalose‐stabilized lyophilized platelets (LP) for control of bleeding in thrombocytopenic dogs. Dogs were randomized to receive 3 × 109 platelets/kg of LP or CPP. Primary outcome measures were change in DOGiBAT score, platelet count, need for additional red cell transfusion and all‐cause mortality.ResultsFifty dogs received LP and 38 received CPP. Baseline demographics and clinical characteristics of both groups were comparable. At 1‐hour post‐transfusion, LP were superior for change in DOGiBAT score, and non‐inferior at 24‐hours post‐transfusion. The LP were non‐inferior to CPP for change in platelet count, need for additional red blood cell units, and survival to discharge. The LP were superior for change in hematocrit at 1‐hour post‐transfusion, and non‐inferior at 24‐hours. No adverse effects were noted in either group.Conclusions and Clinical ImportanceA novel trehalose‐stabilized canine LP product appears to be logistically superior and is clinically non‐inferior to DMSO‐stabilized canine CPP for management of bleeding in thrombocytopenic dogs.

Vector competence of Rhipicephalus sanguineus sensu stricto for Anaplasma platys

Anaplasma platys is a Gram-negative, obligate intracellular bacteria that causes canine infectious cyclic thrombocytopenia in dogs. The brown dog tick Rhipicephalus sanguineus sensu lato is presumed to be the vector of A. platys based on the overlap in distribution of R. sanguineus and A. platys infections, detection of A. platys DNA in both flat and engorged field-collected R. sanguineus, and the fact that dogs are primary hosts of both brown dog ticks and A. platys. However, the only study evaluating the vector competence of R. sanguineus for A. platys under controlled laboratory conditions reported an apparent inability of ticks to acquire or maintain the pathogen. In 2016, engorged female Rhipicephalus sanguineus sensu stricto ticks were collected off dogs to start a laboratory tick colony. After one generation of colony maintenance on tick-naïve and pathogen-free New Zealand White rabbits, a rabbit used to feed F1 adults seroconverted to Anaplasma phagocytophilum antigen. PCR and subsequent DNA sequencing identified the presence of A. platys in both the adult ticks fed on this rabbit and their resulting F2 progenies. Retrospective testing of all previous (P and F1) life stages of this colony demonstrated that the infection originated from one field-collected A. platys-infected female whose progeny was propagated in the laboratory and produced the PCR-positive F1 adults. Over the following (F2-F4) generations, the prevalence of A. platys in this colony reached 90–100 % indicating highly efficient transovarial and horizontal transmission, as well as transstadial maintenance, of this pathogen by R. sanguineus s.s.

Evaluation of the effect of vincristine on platelet count in dogs with lymphoma.

To determine the effect of vincristine administration on the platelet count, platelet morphology and incidence of thrombocytopenia in dogs diagnosed with lymphoma. Medical records of 59 dogs with lymphoma receiving vincristine sulphate were reviewed retrospectively. Following vincristine administration the platelet count was higher and the number of thrombocytopenic patients was lower. No difference was found in the number of dogs with enlarged and elliptical platelets following vincristine treatment. Vincristine administration increases platelet counts in dogs with lymphoma. It is not contra-indicated to administer vincristine to dogs with lymphoma that are thrombocytopenic.

Correlation of rotational thromboelastometry (ROTEM) parameters with platelet count and their ability to predict thrombocytopenia in dogs

The study objectivs were to evaluate the correlation between platelet count (PLT) and rotational thromboelastometry (ROTEM) parameters and to determine ROTEM cut-off values for identification of thrombocytopenia in dogs. Medical records of 113 dogs with concurrent EXTEM (ROTEM activated by proprietary tissue factor), FIBTEM (EXTEM with added cytochalasin D) analysis and PLT were retrospectively reviewed. Signalment, treatment prior to analysis, hematocrit (HCT), EXTEM/FIBTEM maximum clot firmness (MCFEXTEM, MCFFIBTEM), EXTEM/FIBTEM maximum clot elasticity (MCEEXTEM, MCEFIBTEM) and EXTEM maximum lysis (MLEXTEM) were extracted from patient records and ROTEM database. Delta (Δ) MCF was calculated as MCFEXTEM−MCFFIBTEM and ΔMCE as MCEEXTEM−MCEFIBTEM. The PLT was correlated to MCFEXTEM, MCEEXTEM, ΔMCF and ΔMCE using Spearman-Rho analysis. Correlations were further analyzed in thrombocytopenic dogs. The ability to predict thrombocytopenia was evaluated with receiver operating characteristics (ROC). Thirty-seven samples (32.7%) showed thrombocytopenia (<130 × 109/L) and 19 samples (17%) severe thrombocytopenia (<60* x 109/L). The PLT significantly correlated with MCFEXTEM (r = 0.545, P < .001), MCEEXTEM (r = 0.547, P < .001), ΔMCF (r = 0.441, P < .001) and ΔMCE (r = 0.559, P < .001). MCFEXTEM < 49 mm, MCEEXTEM < 93, ΔMCF <42 mm and ΔMCE <90 predicted thrombocytopenia <60 × 109/L with a sensitivity of 90% and a specificity of 78% with a negative predictive value >97% for all 4 parameters. In conclusion, PLT in dogs correlated moderately but significantly with all evaluated ROTEM parameters. All parameters were able to rule out thrombocytopenia <60 × 109/L with a high negative predictive value, while the sensitivity to predict thrombocytopenia was only moderate and the positive predictive value was low.

IDIOPATHIC THROMBOCYTOPENIA IN DOGS - CASE REPORT

Thrombocytopenia represents a significant reduction in number of blood platelets in thecirculation of mammals. The causes of thrombocytopenia in dogs and cats are: various infectiousfactors, viruses, bacterias, parasites, various pathological conditions of the liver, spleen, bonemarrow or autoimmune diseases. Sometimes, thrombocytopenia causes many different factors orthe real cause can not be detected, and its origin is called idiopathic. In our practice, in the course ofhaematological analysis of blood, we encounter a reduced number of platelets in the blood of dogsand cats. Then we are facing the great challenge of diagnosing and treating possible idiopathicthrombocytopenia in animals.In our case, we have a Miniature poodle whose problems began at the age of 2.5. The dog had thefollowing symptoms: inapetency, somnolence, temperature of 38.80C, pale oral mucosa withpetechiae and behavioral changes. After the first hematological blood tests were performed, theresults of the parameters indicated thrombocytopenia in this dog. Diagnosis of the disease issupported by symptoms and differential diagnosis, so we started with frequent monitoring ofhaematological parameters.We included adequate therapy with the first symptoms of the disease in our case of idiopathicthrombocytopenia in a young dog. The therapy was successful, hematological parameters and thequality of life improved, and the dog is now eight years old. The treatment of idiopathicthrombocytopenia is a challenge for every small animal veterinarian and for this reason in this paperwe share our experiences with colleagues.

Molecular evidence of Ehrlichia canis and Anaplasma platys and the association of infections with hematological responses in naturally infected dogs in Kalasin, Thailand.

Background:Tick-borne bacteria, Anaplasma platys and Ehrlichia canis are well recognized as the etiology of anemia and thrombocytopenia in dogs. The clinical signs of anaplasmosis and ehrlichiosis range from asymptomatic to severe symptoms . There are insufficient studies about epidemiological surveys of these blood parasites, also the association of infections with the hematological study.Aim:This study aimed to screen A. platys and E. canis in naturally infected dogs and the effects of the infection on the levels of packed cell volume (PCV) and platelet count.Materials and Methods:A total of 68 blood samples were collected from free-roaming dogs at Nong Kung Sri district, Kalasin Province, Thailand, and examined for A. platys and E. canis infection by polymerase chain reaction (PCR) and measured PCV levels and platelet count.Results:Using nested PCR, 42.65% of dogs were infected with one or two pathogens. The molecular detection of anaplasmosis and ehrlichiosis in this population was 29.4% (95% confidence interval [CI]: 18.98-41.71) and 25% (95% CI: 14.4-35.3), respectively. Coinfection occurred at 11.8% (95% CI: 5.22-21.87). Infection with E. canis and coinfection showed significant association with PCV levels (p<0.05) while A. platys infection showed no statistical relationship. Infection with A. platys, E. canis, and coinfection had a non-significant correlation with platelet count (p>0.05).Conclusion:This study provides data of anaplasmosis and ehrlichiosis in free-roaming dogs which indicated that these zoonotic diseases are widespread and require for disease frequency determination, especially in Kalasin Province of Thailand where data of tick-borne infections in dogs have not been reported.

Long-term outcome of primary immune-mediated thrombocytopenia in dogs.

To determine the incidence of relapse after discharge from the hospital in dogs with a diagnosis of presumed primary immune-mediated thrombocytopenia, risk factors associated with relapse and whether or not indefinite use of immunosuppressive medication influences risk of relapse. Medical records from August 2007 through July 2016 were reviewed to identify dogs with a diagnosis of presumed primary immune-mediated thrombocytopenia. Data collection included signalment, initial diagnostic tests, treatment, incidence of relapse, survival duration and follow-up testing. A total of 45 dogs were diagnosed, treated and monitored for at least oneyear for presumed primary immune-mediated thrombocytopenia. 89∙6% of patients survived to discharge and 31% of those experienced a relapse following discharge. The median time from diagnosis to relapse was 79 days. Of dogs that experienced a relapse, 50% had at least one further relapse. There was no difference in age, body weight, gender, breed, platelet count at presentation, nadir packed cell volume during hospitalisation, incidence of melaena or initial treatment between the relapsing and non-relapsing groups. In the relapsing group, time to platelet recovery was significantly longer and these patients were more likely to have received a blood transfusion. This study does not provide evidence to support the use of long-term immunosuppressive medications to prevent relapse. However, the data suggest that patients with more severe disease at the time of diagnosis or that have already experienced a relapse should be monitored more closely.

Treatment of presumptive primary immune-mediated thrombocytopenia with mycophenolate mofetil versus cyclosporine in dogs.

The objective of this study was to compare hospitalisation duration, survival times, adverse events and cost of therapy in dogs with presumptive primary immune-mediated thrombocytopenia undergoing therapy with mycophenolate mofetil and corticosteroids versus cyclosporine and corticosteroids. A retrospective study of medical case records of dogs with presumed primary immune-mediated thrombocytopenia was conducted. Data collected included signalment, presenting complaints, haematologic and biochemical profiles, vector-borne disease testing, thoracic and abdominal radiographs, abdominal ultrasound, medications administered, duration of hospitalisation, 30- and 60-day survival, adverse events and cost of therapy. Variables were compared between dogs treated solely with mycophenolate mofetil and corticosteroids or cyclosporine and corticosteroids. A total of 55 dogs with primary immune-mediated thrombocytopenia were identified. Eighteen were excluded because multiple immunosuppressive medications were used during treatment. Hospitalisation times, 30-day survival and 60-day survival times were similar between both groups. Dogs in the mycophenolate mofetil/corticosteroid group experienced fewer adverse events than the cyclosporine/corticosteroid group. Therapy with mycophenolate mofetil was less expensive than that with cyclosporine. These results suggest that using the combination of mycophenolate mofetil and corticosteroids appears to be as effective as cyclosporine and corticosteroids in the treatment of presumed primary immune-mediated thrombocytopenia in dogs. Adverse events were less common and cost of therapy was lower in the mycophenolate mofetil group. Additional larger prospective, controlled, double-masked, outcome-based, multi-institutional studies are required to substantiate these preliminary findings.

First identification of Anaplasma platys in the blood of dogs from French Guiana.

Anaplasma platys is the causative agent of infectious cyclic thrombocytopenia in dogs. This infection is worldwide and reported with a higher incidence in tropical and subtropical areas such as South America. Until now, there has been no report of this bacterium in French Guiana. The aim of this study was molecular investigation of A. platys occurrence in the blood of autochthonous dogs in this region. A total 65 blood samples were taken from the shelter dogs in the cities of Cayenne and Kourou, and from dogs of private owners in the city of Cayenne. The results show that at least 15.38% (10/65) were positive to this pathogen. The strain identified in this study has been reported worldwide. These findings should be considered in the way that local veterinarians handle suspected cases of canine anaplasmosis and ehrlichiosis.

Infection with Panola Mountain Ehrlichia sp. in a Dog with Atypical Lymphocytes and Clonal T‐Cell Expansion

Infection with Panola Mountain <i><scp>E</scp>hrlichia</i> sp. in a Dog with Atypical Lymphocytes and Clonal T‐Cell Expansion