Role of electrolytes and unmeasured anions in the metabolic acid-base abnormalities in dogs with parvoviral enteritis

Background: The strong ion model (SIM) is an alternative paradigm in the characterization of acid‐base disturbances particularly in complex disorders. Hypothesis/Objectives: To compare the acid‐base changes in dogs with parvoviral enteritis (PE) using the Henderson‐Hasselbalch (HH) approach, with 2 strong ion approaches. Animals: Forty‐four dogs with PE, and 16 age‐matched control dogs. Methods: Prospective controlled observational study. Acid‐base status was evaluated using the HH model, Fencl‐Stewart (FS) approach and a validated strong ion model (VDM). The acid‐base changes according to each model were classified and compared. Statistical correlations between pH, CO2, and various SIM variables were performed, as well as between the sum of effects (SOE) of the SIM and the individual variables comprising the SOE. Results: The HH model identified acid‐base disorders in 31/44 cases of which 16/31 were mixed with metabolic acidosis and concurrent respiratory alkalosis the most common (10/31). Using the FS approach, metabolic changes were present 36/42 cases, with changes in free water (FW), chloride, and unmeasured anions (UA) being the most prevalent. Both FW and UA correlated well with pH; however, UA were most consistently abnormal in severe acidemia. Similarly to the HH, the VDM detected acid‐base disturbances in 28/44 cases. Major contributors to the acid‐base changes were hyponatremia, hypochloremia, and Atot acidosis because of elevated globulins and increased UA. Conclusions and Clinical Importance: Acid‐base changes are common and complex in dogs with PE, and were easier to understand using a SIM paradigm. Increases in UA have not been documented in PE in dogs

The utility of uric acid assay in dogs as an indicator of functional hepatic mass

Uric acid was used as a test for liver disease before the advent of enzymology. Three old studies criticised uric acid as a test of liver function. Uric acid, as an end-product of purine metabolism in the liver, deserved re-evaluation as a liver function test. Serumtotal bile acids are widely accepted as the most reliable liver function test. This study compared the ability of serumuric acid concentration to assess liver function with that of serumpre-prandial bile acids in dogs. In addition, due to the renal excretion of uric acid the 2 assays were also compared in a renal disease group. Using a control group of healthy dogs, a group of dogs with congenital vascular liver disease, a group of dogs with non-vascular parenchymal liver diseases and a renal disease group, the ability of uric acid and pre-prandial bile acids was compared to detect reduced functional hepatic mass overall and in the vascular or parenchymal liver disease groups separately. Sensitivities, specificities and predictive value parameters were calculated for each test. The medians of uric acid concentration did not differ significantly between any of the groups, whereas pre-prandial bile acids medians were significantly higher in the liver disease groups compared with the normal and renal disease group of dogs. The sensitivity of uric acid in detecting liver disease overall was 65% while the specificity of uric acid in detecting liver disease overall was 59 %. The sensitivity and specificity of uric acid in detecting congenital vascular liver disease was 68%and 59 %, respectively. The sensitivity and specificity of uric acid in detecting parenchymal liver disease was 63%and 60 %, respectively. The overall positive and negative predictive values for uric acid in detecting liver disease were poor and the data in this study indicated uric acid to be an unreliable test of liver function. In dogs suffering from renal compromise serum uric acid concentrations may increase into the abnormal range due to its renal route of excretion.http://www.journals.co.za/ej/ejour_savet.htm

The pathology of the spleen in lethal canine babesiosis caused by Babesia rossi

To provide useful information based on the macropathology, histopathology and immunohistochemical investigation in the spleens of dogs with Babesia rossi infection. Control spleens were collected from four healthy dogs euthanized for welfare reasons. Nine dogs that died naturally because of a mono‐infection with Babesia rossi were selected for the diseased group. One haematoxylin‐and‐eosin–stained section of splenic tissue from each of the infected and control dogs was examined under the light microscope. Immunohistochemical markers were applied to characterize different immunocyte populations. The application of analytic software enabled semi‐quantitative comparison of leucocyte subpopulations. Routine splenic histopathology revealed diffuse intermingling of white and red pulp from infected dogs with a clear loss of distinction between these zones. Immunohistochemistry revealed an increase in the proportion of tissue resident and bone marrow origin macrophages in the infected spleens. Apart from a few remnant lymphocytes within the peri‐arteriolar lymphatic sheaths and follicles, the majority of the immunocytes redistributed to the red pulp, supporting the observation of white and red pulp intermingling. The majority of our findings are in agreement with histomorphological descriptions of the spleen in a variety of noncanid mammalian hosts with lethal malaria or babesiosis.The National Research Foundationhttp://www.wileyonlinelibrary.com/journal/pim2021-03-02hj2021Companion Animal Clinical StudiesParaclinical Science

Biomarkers in canine parvovirus enteritis

Canine parvovirus (CPV) enteritis has, since its emergence in 1978, remained a common and important cause of morbidity and mortality in young dogs. The continued incidence of parvoviral enteritis is partly due to the virus’ capability to evolve into more virulent and resistant variants with significant local gastrointestinal and systemic inflammatory sequelae. This paper reviews current knowledge on historical-, signalment-, and clinical factors as well as several haematological-, biochemical- and endocrine parameters that can be used as diagnostic and prognostic biomarkers in CPV enteritis. These factors include season of presentation, purebred nature, bodyweight, vomiting, leukopaenia, lymphopaenia, thrombocytopaenia, hypercoagulability, hypercortisolaemia, hypothyroxinaemia, hypoalbuminaemia, elevated C-reactive protein and tumour necrosis factor, hypocholesterolaemia and hypocitrullinaemia. Factors contributing to the manifestations of CPV infection are multiple with elements of host, pathogen, secondary infections, underlying stressors and environment affecting severity and outcome. The availability of several prognosticators has made identification of patients at high risk of death and their subsequent targeted management more rewarding.http://www.tandfonline.com/loi/tnzv20hj2014mn201

The central role of chloride in the metabolic acid-base changes in canine parvoviral enteritis

The acid–base disturbances in canine parvoviral (CPV) enteritis are not well described. In addition, the mechanisms causing these perturbations have not been fully elucidated. The purpose of the present study was to assess acid–base changes in puppies suffering from CPV enteritis, using a modified strong ion model (SIM). The hypothesis of the study was that severe acid–base disturbances would be present and that the SIM would provide insights into pathological mechanisms, which have not been fully appreciated by the Henderson–Hasselbalch model. The study analysed retrospective data, obtained from 42 puppies with confirmed CPV enteritis and 10 healthy control dogs. The CPV-enteritis group had been allocated a clinical score, to allow classification of the data according to clinical severity. The effects of changes in free water, chloride, L-lactate, albumin and phosphate were calculated, using a modification of the base excess algorithm. When the data were summated for each patient, and correlated to each individual component, the most important contributor to the metabolic acid–base changes, according to the SIM, was chloride (P < 0.001). Severely-affected animals tended to demonstrate hypochloraemic alkalosis, whereas mildly-affected puppies had a hyperchloraemic acidosis (P = 0.007). In conclusion, the acid–base disturbances in CPV enteritis are multifactorial and complex, with the SIM providing information in terms of the origin of these changes.http://www.elsevier.com/locate/tvjlhb201

Serial haematology results in transfused and non-transfused dogs naturally infected with Babesia rossi

This prospective longitudinal study investigated the progression of haematological changes in 32 transfused and 54 non-transfused dogs naturally infected with Babesia rossi over the 1st 6 days following diagnosis and treatment. The effect of patient age on the results of complete blood counts was determined. Haematology data were analysed at presentation and at 24 hours, 3 days and 6 days after presentation. Dogs were treated with diminazene aceturate at diagnosis and a blood transfusion was given if deemed clinically required. Mildly to moderately regenerative normocytic normochromic anaemia was observed in all dogs throughout the study period. Transfused dogs more often had an inflammatory leukogram at presentation and at 24 hours, than dogs that were not transfused. In dogs with a left shift, a concurrent normal or decreased segmented neutrophil count was found more commonly than neutrophilia. Severe thrombocytopenia that resolved within a week was common. Blood transfusion alleviated the anaemia, but had no significant effect on white blood cell or platelet responses. Blood cell responses were not significantly influenced by age. In conclusion, the red blood cell and white blood cell responses were less than expected in dogs with babesiosis, given the degree of anaemia and inflammation present. The magnitude of thrombocytopenia and rapid return of the platelet count to normal suggested a possible immune-mediated mechanism for the thrombocytopenia.Funding was received from the Faculty of Veterinary Science, University of Pretoria.http://www.journals.co.za/ej/ejour_savet.htm

Clinicopathologic abnormalities associated with snake envenomation in domestic animals

Envenomation of domestic animals by snakes occurs frequently in certain geographic areas. However, reports describing clinical signs, clinicopathologic abnormalities, therapeutic approaches, and outcomes are sparse. This review summarizes various snake families, venom types associated with harmful snakes, and the significant hematologic, hemostatic, and biochemical abnormalities associated with envenomation. Hematologic abnormalities include RBC membrane abnormalities, hemolysis, hemoconcentration, leukogram changes, and platelet abnormalities, specifically thrombocytopenia. Coagulopathies associated with snake envenomation are well described in human medicine, and many studies have demonstrated properties of venoms that lead to both procoagulation and anticoagulation. As expected, similar abnormalities have been described in domestic animals. Biochemical abnormalities are associated with the effects of venom on tissues such as liver, skeletal and cardiac muscle, vascular endothelium, and kidney as well as effects on protein components and cholesterol. This comprehensive review of clinicopathologic abnormalities associated with envenomation and their relationship to characterized venom constituents should be useful both in the diagnosis and management of envenomation and serve as a foundation for future research in this field.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1939-165Xmn201

A flow cytometric assessment of the lymphocyte immunophenotypes in dogs naturally infected with Babesia rossi

Immunity to Babesia infection requires both innate and acquired responses, including cell mediated- and humoral responses. The aims of this study were to investigate the variation in selected peripheral blood lymphocyte phenotypes in dogs with virulent babesiosis at presentation and over time after treatment, and to determine whether these were correlated with the severity of clinical signs. Forty-four dogs naturally infected with B. rossi were studied and 5 healthy dogs were included as controls. Blood samples were collected from the jugular vein at admission, prior to any treatment, and at 24 h and 48–72 h. Leukocytes were incubated with canine specific, fluorochrome conjugated anti-CD3, anti-CD4, anti-CD8, and anti-B cell markers. Babesia-infected dogs were divided into complicated or uncomplicated groups on clinical grounds and in-house laboratory assays. The percentage CD3+ lymphocytes in the complicated group was lower compared to the controls (P = 0.014) and uncomplicated group (P = 0.007). The percentage CD4+ T lymphocytes in the complicated group was lower compared to the controls (P = 0.027) and uncomplicated group (P = 0.014). Both the complicated as well as the uncomplicated groups expressed a lower percentage CD8+ T lymphocytes compared to the control group (P &lt; 0.001 and P = 0.005, respectively). The percentage B lymphocytes was higher in the complicated group at 48–72 h. These findings could indicate the presence of a functional immune suppression secondary to increased apoptosis or redistribution of effector lymphocytes and/or a combination of other immune modulatory mechanisms induced by B. rossi infection.A National Research Foundation Grant (CPRR13080726333) held by AL, the Animal and Zoonotic Diseases Institutional Research Theme (AZT IRT) of the University of Pretoria as well as the Health and Welfare Sector of Education and Training Authority (HWSETA), South Africa.http://www.elsevier.com/locate/vetpar2018-07-15cs2017Companion Animal Clinical StudiesProduction Animal Studie

Excessive pro-inflammatory serum cytokine concentrations in virulent canine Babesiosis

Babesia rossi infection causes a severe inflammatory response in the dog, which is the result of the balance between pro- and anti-inflammatory cytokine secretion. The aim of this study was to determine whether changes in cytokine concentrations were present in dogs with babesiosis and whether it was associated with disease outcome. Ninety-seven dogs naturally infected with B. rossi were studied and fifteen healthy dogs were included as controls. Diagnosis of babesiosis was confirmed by polymerase chain reaction and reverse line blot. Blood samples were collected from the jugular vein at admission, prior to any treatment. Cytokine concentrations were assessed using a canine-specific multiplex assay on an automated analyser. Serum concentrations of interleukin (IL)-2, IL-6, IL-8, IL-10, IL-18, granulocyte-macrophage colony stimulating factor (GM-CSF) and monocyte chemotactic protein-1 (MCP-1) were measured. Twelve of the Babesia-infected dogs died (12%) and 85 survived (88%). Babesia-infected dogs were also divided into those that presented within 48 hours fromdisplaying clinical signs, and those that presented more than 48 hours after displaying clinical signs. Cytokine concentrations were compared between the different groups using the Mann-Whitney U test. IL-10 and MCP-1 concentrations were significantly elevated for the Babesia-infected dogs compared to the healthy controls. In contrast, the IL-8 concentration was significantly decreased in the Babesia-infected dogs compared to the controls. Concentrations of IL-6 andMCP-1 were significantly increased in the non-survivors compared to the survivors. Concentrations for IL-2, IL-6, IL-18 and GM-CSF were significantly higher in those cases that presented during the more acute stage of the disease. These findings suggest that a mixed cytokine response is present in dogs with babesiosis caused by B. rossi, and that an excessive pro-inflammatory response may result in a poor outcome.Supporting Information : S1 File. Cytokine Concentrations in Virulent Canine Babesiosis—Leukocyte Data. (PDF)Supporting Information : S2 File. Cytokine Concentrations in Virulent Canine Babesiosis—APP and Cytokine Data. (PDF)Research Development Fund of the University of Pretoria (AG), South African Veterinary Foundation (AG) and National Research Foundation (JPS).http://www.plosone.orgam2016Companion Animal Clinical Studie

Serial changes in the concentrations of cortisol and thyroid hormones in Beagle dogs infected with Babesia rossi

DATA AVAILABILITY : Data will be made available on request.An experimental infection using Babesia (B.) rossi was performed in healthy male Beagle dogs to assess the changes in endocrine variables during disease. Two dogs were infected with a low dose (LD) of parasite inoculum (104 parasites) and three dogs were infected with a high dose (HD) (108 parasites). Basal serum cortisol, thyroxine (T4), and thyrotropin (TSH) concentrations were measured every second day. Samples were analyzed using a solid- phase, competitive chemiluminescent enzyme immunoassay (Immulyte® 2000, Siemens). Variables were compared between groups and timepoints using linear mixed models. In both groups, the median cortisol concentration increased, whilst the median T4 concentration decreased after infection, with a return towards baseline concentration post treatment. The highest cortisol and the lowest T4 concentrations were reached at 96 h and 108 h post infection, respectively, in the HD group and slightly later at 108 and 144 h postinfection, respectively, in the LD group. A higher cortisol concentration with a more rapid increase, and a lower T4 concentration with a more rapid decline, were associated with disease severity and a higher dose of parasite inoculum. The TSH concentration remained within the reference interval throughout the study period. This study illustrated the temporal changes in endocrine parameters during experimental B. rossi infection and demonstrated that cortisol and T4 tracked the severity of disease, albeit in opposite directions.https://www.elsevier.com/locate/ttbdisam2024Animal and Wildlife SciencesSDG-03:Good heatlh and well-bein