ACVIM consensus statement guidelines for the diagnosis, classification, treatment, and monitoring of pulmonary hypertension in dogs.

Pulmonary hypertension (PH), defined by increased pressure within the pulmonary vasculature, is a hemodynamic and pathophysiologic state present in a wide variety of cardiovascular, respiratory, and systemic diseases. The purpose of this consensus statement is to provide a multidisciplinary approach to guidelines for the diagnosis, classification, treatment, and monitoring of PH in dogs. Comprehensive evaluation including consideration of signalment, clinical signs, echocardiographic parameters, and results of other diagnostic tests supports the diagnosis of PH and allows identification of associated underlying conditions. Dogs with PH can be classified into the following 6 groups: group 1, pulmonary arterial hypertension; group 2, left heart disease; group 3, respiratory disease/hypoxia; group 4, pulmonary emboli/pulmonary thrombi/pulmonary thromboemboli; group 5, parasitic disease (Dirofilaria and Angiostrongylus); and group 6, disorders that are multifactorial or with unclear mechanisms. The approach to treatment of PH focuses on strategies to decrease the risk of progression, complications, or both, recommendations to target underlying diseases or factors contributing to PH, and PH-specific treatments. Dogs with PH should be monitored for improvement, static condition, or progression, and any identified underlying disorder should be addressed and monitored simultaneously

Detection of specific bacterial agents by quantitative PCR assays in the bronchoalveolar lavage fluid of dogs with eosinophilic bronchopneumopathy vs. dogs with chronic bronchitis and healthy dogs

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Generation of a comprehensive molecular cell atlas of the healthy canine lung

peer reviewedSingle cell RNA sequencing (scRNA-seq) is a powerful transcriptomic technique to analyse cell expression profiles across various tissues or conditions, and to identify new cell subpopulations. It has been extensively used in human and mouse studies, and more recently for identification of cellular subpopulations in the bronchoalveolar lavage fluid of dogs. To date, the molecular state of all cell types in canine lung tissue has not been profiled. Such study will help to determine specific cell markers, often lacking in the canine species, and will also provide the foundation for further comparisons with specific lung diseases at single-cell level, such as canine pulmonary fibrosis or neoplasia. In this context, we had a particular interest in fibroblast subpopulations and their expression profiles. Indeed, molecules expressed by fibroblasts (and by cancer-associated fibroblasts) are of potential interest for further development of early markers of disease and of novel molecular fibroblast-targeting therapies. We performed droplet-based scRNA-seq on fresh healthy lung biopsies from three dogs. Two biopsies were collected from dogs euthanized for unrelated reasons, and one was collected from the tumour-free area of a lung lobe resected for primary adenocarcinoma. Biopsies were systematically collected at the peripheral part of the right caudal lobe. Tissues were dissociated to obtain single-cell suspensions, which were loaded into the Chromium Controller (10x Genomics). Clustering, visualization and gene profiling was achieved using the Seurat package in R. Distinct cell populations were identified based on canonical or literature-described cell markers. A total of 22,424 cells were sequenced. Four main cell compartments were identified and individually investigated: epithelial cells (EPCAM+, 5 subpopulations), immune cells (PTPRC+, 17 subpopulations), endothelial cells (PECAM1+, 5 subpopulations) and mesenchymal cells (EPCAM-/PTPRC-/PECAM1-, 10 subpopulations). Clustering resolution was high enough to consistently discriminate different cell subpopulations within classical cell types such as fibroblasts, smooth muscle cells, lymphocytes or macrophages, for example. Among fibroblasts, cluster analysis highlighted subpopulations already identified in humans such as alveolar or adventitial fibroblasts. Differential gene expression profiles were defined for all 37 cell subpopulations, thus identifying new specific cell markers for all cells of the canine lung. This is the first report of scRNA-seq analysis of canine lung tissue, expanding our knowledge of canine distal lung cell subpopulations. This study provides the foundation for comparisons with specific lung diseases at single-cell level, such as canine pulmonary fibrosis or canine pulmonary neoplasia, for which development of emerging therapies are cruelly required

Biomolecular investigation for Capillaria spp. infections on bronchoalveolar lavage fluid of owned domestic dogs presented for chronic cough in Belgium

peer reviewedThe trichuroid parasitic nematode Capillaria aerophila (syn. Eucoleus aerophilus) is responsible for lower respiratory infections and Capillaria boehmi (syn. Eucoleus boehmi) for sino-nasal infections in wild and domestic carnivores. Animals become infected by eating environmental embryonated eggs or earthworms. The adult worms live embedded in the epithelia of the bronchioles, bronchi, and trachea or in the nasal sinuses, respectively. Infections with C. aerophila can be sub-clinical or lead to chronic bronchial inflammation, rarely bronchopneumonia. C. boehmi may cause nasal discharge, sneezing or olfactory impairment. Knowledge about prevalence and distribution of both parasites beyond Eastern Europe and Mediterranean countries is lacking. The aim of this study was to assess the prevalence of C. aerophila infection in coughing, client-owned, domestic dogs in Belgium. Stored bronchoalveolar lavage fluid (BALF) from 125 dogs (median age 7.3 years, range: 0.3-17.2 years) from March 2018-2022 was retrieved. All dogs had history of chronic cough (> 2 weeks duration) and underwent BALF collection for microbiologic testing of common respiratory pathogens. DNA extracted from BALF samples was stored at -80°C until further analysis. A conventional polymerase chain reaction targeting a region internal to the cox1 gene of C. aerophila, a Capillarinae consensus sequence, was performed on BALF samples in duplicate and in batch analysis using previously published primers sequences. DNA of adult C. boehmi specimens was included as a positive control. Molecular grade water was used as a negative control. Neither DNA of C. aerophila nor C. boehmi were detected in the BALF samples. Sixty-seven dogs (54%) had a recent history of deworming against lungworms with either moxidectin or fenbendazole (deworming protocol not standardized), 9 dogs (7%) were not up to date with deworming therapy, and the remaining 49 dogs (39%) had unknown deworming status. Result of this study suggest that C. aerophila infection is not prevalent in Belgium in dogs with chronic cough. This might be explained by recent deworming therapy in half of the included dogs. Epidemiosurveillance of capillarid infection may be considered in wild canids, such as foxes, to determine whether these parasites are a potential risk for domestic animals

Variations in facial conformation are associated with differences in nasal microbiota in healthy dogs.

peer reviewedBackground: Extrinsic and intrinsic factors have been shown to infuence nasal microbiota (NM) in humans. Very few studies investigated the association between nasal microbiota and factors such as facial/body conformation, age, and environment in dogs. The objectives are to investigate variations in NM in healthy dogs with diferent facial and body conformations. A total of 46 dogs of diferent age, living environment and from 3 diferent breed groups were recruited: 22 meso−/dolichocephalic medium to large breed dogs, 12 brachycephalic dogs and 12 terrier breeds. The nasal bacterial microbiota was assessed through sequencing of 16S rRNA gene (V1-V3 regions) amplicons. Results: We showed major diferences in the NM composition together with increased richness and α-diversity in brachycephalic dogs, compared to meso−/dolichocephalic medium to large dogs and dogs from terrier breeds. Conclusion: Healthy brachycephalic breeds and their unique facial conformation is associated with a distinct NM profle. Description of the NM in healthy dogs serves as a foundation for future researches assessing the changes associated with disease and the modulation of NM communities as a potential treatment

Angiostrongylosis in dogs with negative fecal and in-clinic rapid serological tests: 7 Cases (2013-2017)

Background: Angiostrongylosis is considered as emerging disease in dogs in Belgium. Detection of first-stage larvae in feces using the Baermann method has an imperfect sensitivity. Objectives: Investigation of efficacy of noninvasive blood and fecal diagnostic tests in comparison with PCR on bronchoalveolar lavage (BAL) material in a small series of coughing or dyspnoeic dogs naturally infected with Angiostrongylus vasorum. Animals: Seven dogs with angiostrongylosis. Methods: Retrospective study. Dogs with cough, exercise intolerance and dyspnea of 2- to 8-week duration. Diagnostic methods used included Baermann analysis, AngioDetect rapid assay, ELISAs for detection of circulating antigen and specific antibodies and qPCR on BAL material. Results: Baermann analysis, AngioDetect rapid assay, antigen ELISA, antibody ELISA, and qPCR on BAL material were positive in 3/7, 2/7, 3/6, 6/6, and 7/7 dogs, respectively. ELISA for antibodies or qPCR on BAL material were essential for definitive diagnosis in 3 dogs. Relative sensitivities of AngioDetect rapid assay, Baermann analysis, and ELISA for antigen detection were lower than 50% compared with ELISA for antibodies or qPCR on BAL material. Conclusion and Clinical Importance: In this small clinical series, Baermann analysis and AngioDetect rapid assay failed to confirm the diagnosis in some dogs. Therefore, ELISA for antibody detection and qPCR on BAL material should strongly be considered in clinically suspected dogs when antigen detection methods (AngioDetect or ELISA) and Baermann analysis are negative. Copyright © 2018 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.Peer reviewe

Assessment of SPP1 and FN1 in serum, BALF and lung tissue samples from dogs affected with CIPF

Background: Canine idiopathic pulmonary fibrosis (CIPF) is a chronic disease affecting West Highland white terriers (WHWTs)1,2. Osteopontin (SPP1) and fibronectin (FN1) are associated with pulmonary fibrosis in men3-6 and are overexpressed in bronchoalveolar lavage fluid (BALF) macrophage clusters in CIPF7. Study premise: The aim is to investigate whether these molecules are potential disease markers. SPP1 and FN1 serum and BALF concentrations were measured using canine ELISA kits in CIPF WHWTs (n=24), healthy aged-matched WHWTs (n=13) and healthy terriers (n=15). Proteins were also localized in lung tissue by immunohistochemistry. Results: SPP1 serum concentrations were higher in CIPF compared with healthy WHWTs and terriers, and in healthy WHWTs compared with terriers. There were negatively correlated with PaO2 in WHWTs. Higher SPP1 BALF concentrations were found in CIPF and healthy WHWTs compared with terriers. Intense labelling was reported in all groups in ciliated epithelial cells, smooth muscular cells surrounding large vessels and some macrophages. Moreover, in all CIPF WHWTs, the pneumocytes II and the extra cellular matrix were labelled, while it was the case in only 57% of healthy WHWTs and not present in terriers. FN1 serum concentrations were lower in CIPF and healthy WHWTs compared with terriers. No difference was found between groups in BALF. There was no evidence of differences in FN1 labelling. Conclusions: The results suggest that SPP1 is involved in CIPF pathogenesis and could predispose that breed to the disease. However, further studies are required to determine its interest as biomarker or potential therapeutic target

The Middle Ear Microbiota in Healthy Dogs Is Similar to That of the External Ear Canal

peer reviewedOtitis media can be a consequence of chronic otitis externa and could represent a perpetuating factor. While the microbiota of the EEC in healthy dogs and in the presence of otitis externa has been described, only sparse information is available concerning the normal microbiota of the middle ear. The objective was to compare the tympanic bulla (TB) with the external ear canal (EEC) microbiota in healthy dogs. Six healthy experimental Beagle dogs were selected based on the absence of otitis externa, negative cytology and bacterial culture from the TB. Samples from the EEC and TB were collected directly after death using a total ear canal ablation and lateral bulla osteotomy. The hypervariable segment V1–V3 of the 16S rDNA was amplified and sequenced with a MiSeq Illumina. The sequences were analyzed by the Mothur software using the SILVA database. No significant differences between the EEC and TB microbiota for the Chao1 richness index (p = 0.6544), the Simpson evenness index (p = 0.4328) and the reciprocal Simpson alpha diversity (p = 0.4313) were noted (Kruskal-Wallis test). A significant difference (p = 0.009) for the Chao1 richness index between the right and left EEC was observed. The microbiota profile was similar in the EEC and the TB of the Beagles