Proposed protocol for utilising high-flow nasal oxygen therapy in treatment of dogs hospitalised due to pneumonia.

BACKGROUND: High-flow nasal oxygen (HFNO) therapy is a non-invasive respiratory support method that provides oxygen-enriched, warmed, and humidified air to respiratory-compromised patients. It is widely used in human medical care, but in veterinary medicine it is still a relatively new method. No practical guidelines exist for its use in canine pneumonia patients, although they could potentially benefit from HFNO therapy. This study aims to provide a new, safe, non-invasive, and effective treatment protocol for oxygen supplementation of non-sedated dogs with pneumonia. METHODS: Twenty privately owned dogs with pneumonia will receive HFNO therapy at a flow rate of 1-2 L/kg, and the fraction of inspired oxygen will be determined individually (ranging from 21% to 100%). HFNO therapy will continue as long as oxygen support is needed based on clinical evaluation. Patients will be assessed thrice daily during their hospitalisation, with measured primary outcomes including partial pressure of oxygen, oxygen saturation, respiratory rate and type, days in hospital, and survival to discharge. DISCUSSION: The proposed protocol aims to provide a practical guideline for applying HFNO to dogs hospitalised due to pneumonia. The protocol could enable more efficient and well-tolerated oxygenation than traditional methods, thus hastening recovery and improving survival of pneumonia patients.

Comparison of habitual physical activity in French Bulldogs, Pugs and normocephalic dogs by accelerometry.

Brachycephalic obstructive airway syndrome (BOAS) is a major welfare concern in flat-faced dog breeds. As BOAS causes respiratory difficulties and exercise intolerance, it can reduce dogs' daily quality of life (QOL). However, evaluation of QOL in dogs is difficult, and many owners perceive BOAS signs as 'normal' for the breed. Accelerometers that measure frequency, duration and intensity of activities can offer an objective way of evaluating dogs' daily activity and thereby deliver potential insights into QOL. The aim of this study was to assess habitual physical activity of 48 brachycephalic and 23 non-brachycephalic dogs using accelerometers. The accelerometers were used for one week and owners filled in a questionnaire regarding their dog's well-being and activities. Veterinary-assessed BOAS grading for brachycephalic dogs was determined. Compared with controls, more severely affected French Bulldogs and Pugs had significantly lower total activity counts and spent less time in high activity. In Pugs, mildly affected dogs were also less active, but age can be a contributing factor here, as older age decreased activity in Pugs and controls showed a wider age range. In French Bulldogs, those dogs with no or mild signs of BOAS did not differ from controls regarding their daily activity. In conclusion, accelerometers were easy to use for objective measurement of daily activity in bracycephalic dogs, although a degree of discomfort due to the collar was reported. Results showed that BOAS signs were associated with decreased habitual physical activity. These findings emphasise the importance of actions taken to reduce incidence of BOAS in brachycephalic breeds.

Quantitative proteomic analysis of bronchoalveolar lavage fluid in West Highland white terriers with canine idiopathic pulmonary fibrosis.

BACKGROUND: Canine idiopathic pulmonary fibrosis (CIPF) is a chronic, progressive, interstitial fibrosing lung disease, manifesting as cough, exercise intolerance and ultimately, dyspnea and respiratory failure. It mainly affects West Highland white terriers (WHWTs), lacks curable treatment and has a poor prognosis. Aspiration of gastroesophageal refluxate may play a role in the development of CIPF. In the first part of this study, we completed label-free quantitative proteomic analysis of bronchoalveolar lavage fluid (BALF) from CIPF and healthy WHWTs. In the second part, we evaluated potential protein markers of reflux aspiration from canine gastric juice and vomitus and whether these were present in BALF from the two groups. RESULTS: Across all BALF samples, 417 proteins were identified, and of these, 265 proteins were identified by two or more unique tryptic peptides. Using the 265 high confidence assignments, the quantitative proteome profiles were very similar in the two cohorts, but they could be readily resolved by principal component analysis on the basis of differential protein expression. Of the proteins that were differentially abundant in the two groups, several (including inflammatory and fibrotic markers) were elevated in CIPF, and a smaller, more diverse group of proteins were diminished in CIPF. No protein markers indicative of reflux aspiration were identified. CONCLUSIONS: Label-free proteomics allowed discrimination between CIPF and healthy WHWTs, consistent with fibrotic process but did not provide clear evidence for gastrointestinal aspiration. The measurement of proteins may provide a proteomics signature of CIPF that could be used to evaluate treatment options.

Skin and ear health in a group of English bulldogs in Finland - a descriptive study with special reference to owner perceptions.

BACKGROUND: Dermatological conditions are common in English bulldogs (EBs). HYPOTHESIS/OBJECTIVES: This cross-sectional study describes the dermatological health status of a group of EBs and compares the results with owner perceptions and its possible impact on quality of life (QoL). Computed tomographic (CT) findings of the ear canals were compared between EBs and mesaticephalic dogs. ANIMALS: Twenty-seven EBs participating in a health study in Finland. METHODS AND MATERIALS: A QoL questionnaire was completed for EBs with owner-reported clinical signs referable to the skin or ear. Clinical evaluation included recording the Canine Atopic Dermatitis Extent and Severity Index, the Otitis Index Score, false paw pad grading and the presence of interdigital furunculosis. These were summed to form a total clinical score (TCS). The cross-sectional surface areas of the horizontal ear canals were measured from CT images and compared with respective images of 14 mesaticephalic dogs collected from a patient database. RESULTS: All 27 EBs had abnormal findings on dermatological examination, but 37% of the owners had not recognized skin or ear signs. The median QoL score was 5.0 (range 0-12) and correlated with TCS (correlation coefficient = 0.507, P < 0.05). English bulldogs had narrower horizontal ear canals than mesaticephalic dogs (P < 0.001). CONCLUSIONS AND CLINICAL IMPORTANCE: All EBs had abnormal dermatological findings that were unnoticed or considered to be of minor significance to the QoL by most owners. Narrow ear canals were common, possibly related to the brachycephalic conformation of the breed.

Thoracic high resolution CT using the modified VetMousetrap™ device is a feasible method for diagnosing canine idiopathic pulmonary fibrosis in awake West Highland White Terriers.

Canine idiopathic pulmonary fibrosis is a chronic, progressive interstitial lung disease particularly prevalent in West Highland White Terriers. In the present prospective pilot study, we evaluated the feasibility of modified VetMousetrap™ device in high resolution CT to detect idiopathic pulmonary fibrosis in West Highland White Terriers. Twelve awake West Highland White Terriers with canine idiopathic pulmonary fibrosis and 24 clinically healthy West Highland White Terriers were scanned using a helical dual slice scanner utilizing VetMousetrap™ device without or with minimal chemical restraint with butorphanol. Three evaluators blindly assessed the images for image quality and the presence of canine idiopathic pulmonary fibrosis related imaging findings such as ground glass opacity and reticular opacities. Additionally, the attenuation of the lung was quantified with ImageJ software using histogram analysis of density over the lung fields. Computed tomography was successfully completed and motion artifact ranked in statistical analysis barely noticeable to mild in all dogs. The agreement between imaging findings and clinical status was very good with overall κ value 0.91 and percentage of agreement of 94%. There was also very good intraobserver (κrange = 0.79-0.91) and interobserver agreement (κ = 0.94). Moderate to severe ground glass opacity was present in all affected dogs. In the ImageJ analysis, a significant difference in lung attenuation between the study groups was observed. We conclude that modified VetMousetrap™ device is applicable in diagnosing canine idiopathic pulmonary fibrosis in awake West Highland White Terriers avoiding anesthetic risk in these often severely hypoxic patients.

S100A12 concentrations and myeloperoxidase activities are increased in the intestinal mucosa of dogs with chronic enteropathies.

BACKGROUND: Intestinal mucosal S100A12 and myeloperoxidase (MPO) are inflammatory biomarkers in humans with inflammatory bowel disease (IBD). However, these biomarkers have not been studied in the intestinal mucosa of dogs with chronic enteropathies (CE), even though dogs with CE have increased S100A12 concentrations in feces and serum. This study investigated mucosal S100A12 concentrations and MPO activities in both dogs with CE and healthy Beagles. ELISA (S100A12 concentrations) and spectrophotometric methods (MPO activity) were used. The associations of both biomarkers with canine IBD activity index (CIBDAI), histopathologic findings, clinical outcome, and serum albumin concentrations were also investigated. We studied intestinal mucosal samples originating from different intestinal regions of 40 dogs with CE and 18 healthy Beagle dogs (duodenum, ileum, colon, and cecum). RESULTS: Compared with healthy Beagles, mucosal S100A12 concentrations in dogs with CE were significantly higher in the duodenum (p < 0.0001) and colon (p = 0.0011), but not in the ileum (p = 0.2725) and cecum (p = 0.2194). Mucosal MPO activity of dogs with CE was significantly higher in the duodenum (p < 0.0001), ileum (p = 0.0083), colon (p < 0.0001), and cecum (p = 0.0474). Mucosal S100A12 concentrations in the duodenum were significantly higher if the inflammatory infiltrate consisted mainly of neutrophils (p = 0.0439) or macrophages (p = 0.037). Mucosal S100A12 concentrations also showed a significant association with the severity of total histopathological injury and epithelial injury in the colon (p < 0.05). Mucosal MPO activity showed a significant association (p < 0.05) with the severity of total histopathological injury, epithelial injury, and eosinophil infiltration in the duodenum. There was no significant association of both biomarkers with CIBDAI or clinical outcome. CONCLUSIONS: This study showed that both mucosal S100A12 concentrations and MPO activities are significantly increased in the duodenum and colon of dogs with CE; mucosal MPO was also increased in the ileum and cecum. Future research should focus on assessing the clinical utility of S100A12 and MPO as diagnostic markers in dogs with CE.

S100A12 concentrations and myeloperoxidase activity in the intestinal mucosa of healthy dogs.

BACKGROUND: Relatively few laboratory markers have been evaluated for the detection or monitoring of intestinal inflammation in canine chronic enteropathies, including inflammatory bowel disease (IBD). Previous research found that the intestinal mucosal levels of S100A12 and myeloperoxidase (MPO), as biomarkers of gut inflammation, were elevated in human patients with IBD. To date, the S100A12 and MPO levels in intestinal mucosal samples from either healthy dogs or from dogs suffering from IBD remain unreported. Therefore, this study aimed to evaluate the mucosal S100A12 and MPO levels in four different parts of the intestine (duodenum, jejunum, ileum and colon) in 12 healthy laboratory Beagle dogs using the ELISA and spectrophotometric methods, respectively. RESULTS: Based on histological examinations, the recorded findings for all the samples were considered normal. The mucosal concentration of S100A12 in the ileum was significantly higher than in all other segments of the intestine (p < 0.05). MPO activity was significantly higher in the ileal, jejunal and duodenal than in colonic mucosal samples (p < 0.05). Moreover, its concentration was higher in the jejunum than in the duodenum. CONCLUSIONS: This study showed that S100A12 and MPO are reliably detectable in canine intestinal mucosa. The assays used appeared to be sufficient to further evaluate the role of S100A12 and MPO in the pathogenesis of canine chronic enteropathies, including IBD. These biomarkers may play a role in the initial detection of gut inflammation suggesting the need for further investigations to confirm IBD or to differentiate between IBD subtypes. Understanding the role of S100A12 and MPO in the pathogenesis of chronic intestinal inflammation in future may result in an improved understanding of canine chronic intestinal inflammation.

Management of a congenital tracheoesophageal fistula in a young Spanish water dog.

BACKGROUND: Tracheoesophageal fistula (TEF) in dogs is a rare disease with only few reports in the literature. This report aims to contribute to the current literature on suitable diagnostic methods for TEF and to provide follow-up information after successful surgical treatment. CASE PRESENTATION: A seven-month-old intact female Spanish Water Dog was presented for further investigation of recurrent respiratory symptom. Bronchoscopy revealed a small hole-like defect in the tracheal wall at the bifurcation. The finding of the contrast material swallow study under fluoroscopy was indicative of a TEF. To further evaluate the connection between the trachea and esophagus, a computed tomography scan was performed. The TEF was surgically approached by thoracotomy through the right lateral sixth intercostal space. The fistula was identified, double ligated and divided. Histopathology confirmed the process to originate from the esophagus and to be patent. The dog was re-examined two weeks and ten months after surgery, with no evidence of recurring clinical signs. CONCLUSIONS: Contrast material swallow study using fluoroscopy was the most reliable diagnostic method. Bronchoscopy may allow the fistula to be visualized, but due to a small fistular opening it can lead to a false negative result. Surgical correction by ligation and dividing of the fistula suggests a good prognosis for early diagnosed and operated TEF.

Evaluation of risk factors for sleep-disordered breathing in dogs.

BACKGROUND: Brachycephalic dogs display sleep-disordered breathing (SDB). The risk factors for SDB remain unknown. OBJECTIVES: To identify risk factors for SDB. We hypothesized that brachycephaly, increasing severity of brachycephalic obstructive airway syndrome (BOAS), excess weight, and aging predispose to SDB. ANIMALS: Sixty-three privately owned pet dogs were prospectively recruited: 28 brachycephalic and 35 normocephalic (mesaticephalic or dolicocephalic) dogs. METHODS: Prospective observational cross-sectional study with convenience sampling. Recording with the neckband was done over 1 night at each dog's home. The primary outcome measure was the obstructive respiratory event index (OREI). Body condition score (BCS) was assessed, and BOAS severity was graded for brachycephalic dogs. RESULTS: Brachycephaly was a significant risk factor for high OREI value (ratio of the geometric means 5.6, 95% confidence interval [CI] 3.2-9.9; P < .001) but aging was not (1.1, 95% CI 1.0-1.2; P = .2). Excess weight, defined as a BCS of over 5/9, (3.5, 95% CI 1.8-6.7; P < .001) was a significant risk factor. In brachycephalic dogs, BOAS-positive class (moderate or severe BOAS signs) was a significant risk factor (2.5, 95% CI 1.1-5.6; P = .03). CONCLUSIONS AND CLINICAL IMPORTANCE: Brachycephaly decreases welfare in a multitude of ways, including disrupting sleep. Brachycephaly, increasing severity of BOAS and excess weight are risk factors for obstructive SDB.

Description of a novel method for detection of sleep-disordered breathing in brachycephalic dogs.

BACKGROUND: Sleep-disordered breathing (SDB), defined as any difficulty in breathing during sleep, occurs in brachycephalic dogs. Diagnostic methods for SDB in dogs require extensive equipment and laboratory assessment. OBJECTIVES: To evaluate the usability of a portable neckband system for detection of SDB in dogs. We hypothesized that the neckband is a feasible method for evaluation of SDB and that brachycephaly predisposes to SDB. ANIMALS: Twenty-four prospectively recruited client-owned dogs: 12 brachycephalic dogs and 12 control dogs of mesocephalic or dolicocephalic breeds. METHODS: Prospective observational cross-sectional study with convenience sampling. Recording was done over 1 night at each dog's home. The primary outcome measure was the obstructive Respiratory Event Index (OREI), which summarized the rate of obstructive SDB events per hour. Additionally, usability, duration of recording, and snore percentage were documented. RESULTS: Brachycephalic dogs had a significantly higher OREI value (Hodges-Lehmann estimator for median difference = 3.5, 95% confidence interval [CI] 2.2-6.8; P < .001) and snore percentage (Hodges-Lehmann estimator = 34.2, 95% CI 13.6-60.8; P < .001) than controls. A strong positive correlation between OREI and snore percentage was detected in all dogs (rs = .79, P < .001). The neckband system was easy to use. CONCLUSIONS AND CLINICAL IMPORTANCE: Brachycephaly is associated with SDB. The neckband system is a feasible way of characterizing SDB in dogs.

Extraesophageal reflux and reflux aspiration in dogs with respiratory diseases and in healthy dogs.

BACKGROUND: Salivary bile acids are used to diagnose extraesophageal reflux (EER) and to evaluate the risk of reflux aspiration that is associated with respiratory diseases in dogs. OBJECTIVES: To study total bile acid (TBA) concentrations in saliva and in bronchoalveolar lavage fluid (BALF) to investigate EER and reflux aspiration in dogs with respiratory diseases and in healthy dogs. ANIMALS:  Thirty-one West Highland White Terriers (WHWTs) with idiopathic pulmonary fibrosis (IPF), 12 dogs with inflammatory airway disease (IAD), 6 dogs with recurrent pneumonia (RP), 26 brachycephalic dogs (BD), 27 healthy WHWTs (HW), 52 healthy dogs (HD). All privately-owned dogs. METHODS: Saliva and BALF were collected from dogs in each group. RESULTS: Salivary TBA concentrations were higher in IPF (median 0.1692 µM, interquartile range [IQR] 0.1115-0.2925 µM, Cohen's d 3.4, 95% confidence interval [CI] 2.2-4.0, P < .001) and BD (0.0256 µM, IQR 0.0086-0.0417 µM, d 0.5, CI -0.1 to 1.1, P = .003) compared to HD (0 µM, IQR not quantifiable [n.q.]-0.0131 µM). Bronchoalveolar lavage fluid TBA concentrations were higher in IPF (0.0117 µM, IQR 0.0048-0.0361 µM, d 0.5, CI 0-1.1, P < .001) compared to HD (0 µM, IQR n.q.-0.0074 µM). CONCLUSION AND CLINICAL IMPORTANCE: Extraesophageal reflux and reflux aspiration occur in healthy dogs and those with respiratory diseases.

Polycythemia in dogs with chronic hypoxic pulmonary disease.

BACKGROUND: Prolonged tissue hypoxia caused by chronic pulmonary disease is commonly regarded as an important mechanism in the development of secondary polycythemia, but little clinical data are available to support this hypothesis. OBJECTIVE: To study the prevalence and severity of erythrocytosis accompanying chronic hypoxic pulmonary disease in dogs. ANIMALS: Forty-seven dogs with hypoxic chronic pulmonary disease, 27 dogs with nonhypoxic chronic pulmonary disease, and 60 healthy controls. METHODS: Dogs with chronic pulmonary disease and chronic hypoxemia (partial pressure of arterial oxygen [PaO2 ] < 80 mm Hg on at least 2 arterial blood gas measurements a minimum of 1 month apart) were identified retrospectively from patient records. Association between arterial oxygen and red blood cell parameters was analyzed using Pearson's correlation coefficients and multivariable linear regression analysis. RESULTS: Red blood cell parameters measured at the end of the hypoxemia period were within the laboratory reference range in most dogs. In chronically hypoxemic dogs, hematocrit (Hct) was increased in 4/47 (8.5%; 95% confidence interval [CI], 0-17) dogs, erythrocyte count (Erytr) was increased in 12/47 (26%; 95%CI, 13-38) dogs and hemoglobin concentration (Hb) was increased in 3/47 (6.4%; 95%CI, 0-14) dogs. No marked polycythemia (Hct ≥65%) was noted in any of the dogs. Red blood cell parameters were not associated with the severity of hypoxemia (correlation to PaO2 : Erytr, r = -.14; Hb, r = -.21; Hct, r = -.14; P > .05 for all). CONCLUSIONS AND CLINICAL IMPORTANCE: Polycythemia is uncommon, and usually mild if present, in dogs with chronic hypoxia caused by pulmonary disease.

Matrix metalloproteinase-2, -7, and -9 activities in dogs with idiopathic pulmonary fibrosis compared to healthy dogs and dogs with other respiratory diseases.

BACKGROUND: Canine idiopathic pulmonary fibrosis (CIPF) is a chronic, interstitial lung disease that mainly affects West Highland white terriers (WHWTs) and is characterized by excessive deposition of extracellular matrix (ECM) in the lung. Matrix metalloproteinases (MMPs) participate in remodeling of ECM. OBJECTIVES: To compare metalloproteinase-2, -7 and -9 activities in blood or bronchoalveolar lavage fluid (BALF) samples or both of CIPF WHWTs with healthy WHWTs, healthy dogs of other breeds, and dogs with other lung diseases and determine if these MMPs could be used as diagnostic and prognostic markers for CIPF. ANIMALS: Forty-four CIPF WHWTs, 24 dogs with chronic bronchitis (CB), 17 with eosinophilic bronchopneumopathy (EBP), 10 with bacterial pneumonia, 39 healthy WHWTs, and 35 healthy dogs of other breeds. METHODS: Cross-sectional observational study. Pro-MMP and active MMP activities were analyzed by zymography. RESULTS: In serum, significantly higher (P < .01) pro-MMP-7 activities were observed in CIPF WHWTs compared to healthy dogs of other breeds, dogs with CB and dogs with EBP. In BALF of CIPF WHWTs, both pro-MMP-9 and pro-MMP-2 activities were significantly higher (P < .01) compared to healthy WHWTs, but these differences were not detected in plasma. The CIPF WHWTs had significantly higher (P < .05) activities of pro-MMP-9 compared to dogs with CB and of pro-MMP-2 compared to dogs with CB and EBP. No statistically significant prognostic factors were observed in CIPF WHWTs. CONCLUSIONS AND CLINICAL RELEVANCE: Serum MMP-7 and BALF MMP-2 and -9 potentially may be useful diagnostic markers but not prognostic markers for CIPF.

Early detection of ketoprofen-induced acute kidney injury in sheep as determined by evaluation of urinary enzyme activities.

OBJECTIVE: To evaluate early indicators of renal tissue destruction and changes in urinary enzyme activities in sheep during the first hours after acute kidney injury induced by administration of an overdose of an NSAID. ANIMALS: 12 adult female sheep. PROCEDURES: Acute kidney injury was induced in 6 sheep by administration of ketoprofen (30 mg/kg, IV) and detected by evaluation of urinary protein concentration, iohexol clearance, and results of histologic examination. Six sheep served as control animals. Blood and urine samples were collected for up to 24 hours after administration of ketoprofen. Plasma concentrations of urea, creatinine, albumin, and total protein; plasma activities of alkaline phosphatase, acid phosphatase, γ-glutamyl transpeptidase (GGT), matrix metalloproteinase (MMP)-2, and MMP-9; and urinary creatinine and protein concentrations, specific gravity, and activities of alkaline phosphatase, acid phosphatase, GGT lactate dehydrogenase, N-acetyl-ß-D-glucosaminidase (NAG), MMP-2, and MMP-9 were measured. Urinary protein concentration and enzyme activities were normalized on the basis of urinary creatinine concentrations and reported as ratios. RESULTS: Many urinary enzyme-to-creatinine ratios increased before the plasma creatinine concentration exceeded the reference value. Urine NAG, lactate dehydrogenase, and acid phosphatase activities were increased beginning at 2 hours after ketoprofen administration, and alkaline phosphatase, GGT, and MMP-2 activities were increased beginning at 4 hours after ketoprofen administration. Most peak urinary enzyme-to-creatinine ratios were detected earlier than were the highest plasma creatinine and urea concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Urinary enzyme activities were sensitive early indicators of acute kidney injury induced by an overdose of an NSAID in sheep.

Update on Canine Idiopathic Pulmonary Fibrosis in West Highland White Terriers.

Canine idiopathic pulmonary fibrosis (CIPF) is a chronic, progressive, interstitial lung disease (ILD) affecting older West Highland white terriers (WHWTs). According to one classification, CIPF is a familial fibrotic ILD in the group of idiopathic interstitial pneumonias. Etiology is unknown but likely arises from interplay between genetic and environmental factors. CIPF shares features with human idiopathic pulmonary fibrosis and human nonspecific interstitial pneumonia. This article describes clinical signs, findings in physical examination, arterial oxygenation, diagnostic imaging, bronchoscopy, bronchoalveolar lavage, histopathology, disease course, and outcome of WHWTs with CIPF; compares canine and human diseases; summarizes biomarker research; and gives an overview of potential treatment.

Recurrent bacterial pneumonia in Irish Wolfhounds: Clinical findings and etiological studies.

BACKGROUND: Increased incidence of bacterial pneumonia (BP) has been reported in Irish Wolfhounds (IWHs), and recurrence of BP is common. The etiology of recurrent pneumonia in IWHs is largely unknown. OBJECTIVES: To describe clinical findings in IWHs with recurrent BP and investigate possible etiologies. ANIMALS: Eleven affected IWHs, 25 healthy IWHs, 28 healthy dogs of other Sighthound breeds, and 16 healthy dogs of other breeds. METHODS: Prospective cross-sectional observational study. All affected IWHs underwent thorough clinical examinations including thoracic radiographs, thoracic computed tomography, electron microscopic evaluation of ciliary structure, and bronchoscopy and bronchoalveolar lavage fluid (BALF) cytology and culture. Serum and BALF immunoglobulin concentrations were measured using an ELISA method, and peripheral blood lymphocyte subpopulations were analyzed using flow cytometry. Esophageal function was assessed by fluoroscopy (n = 2). RESULTS: Median age of onset was 5.0 years (range, 0.4-6.5 years), and when presented for study, dogs had experienced a median of 5 previous episodes of BP (range, 2-6). The following predisposing factors to BP were detected: focal bronchiectasis (10/11), unilateral (2/9) and bilateral (1/9) laryngeal paralysis, and esophageal hypomotility (2/2). Local or systemic immunoglobulin deficiencies or primary ciliary defects were not detected. CONCLUSIONS AND CLINICAL IMPORTANCE: Recurrent BP affects mostly middle-aged and older IWHs without any evident immune deficit or primary ciliary defects. Focal BE was a frequent finding in affected dogs and likely contributed to the development of recurrent respiratory infections. Laryngeal and esophageal dysfunction identified in a minority of dogs may contribute to recurrent BP.

Comparison of Tracheal Wash and Bronchoalveolar Lavage Cytology in 154 Horses With and Without Respiratory Signs in a Referral Hospital Over 2009-2015.

Most equine lower respiratory diseases present as increased airway neutrophilia, which can be detected in tracheal wash (TW) or bronchoalveolar lavage fluid (BALF) cytology samples. The aim was to compare the TW and BALF results in a population of client-owned horses with and without clinical respiratory disease signs. A secondary aim was to determine the sensitivity (Se) and specificity (Sp) of TW and BALF neutrophilia in detecting respiratory disease. The cutoff values for neutrophils were also evaluated. Retrospective data from 154 horses of various breeds that had been subject to both TW and bronchoalveolar lavage (BAL) sampling at rest during 2009-2015 were used. The horses were divided into three groups based on the presenting signs, physical examination, and endoscopy mucus score. Neutrophil counts of >20% in TW and >5% in BAL were considered abnormal. Cytology results between groups, correlations between TW and BALF cell types, and tracheal mucus score were analyzed. Two graph receiving operating characteristic (ROC) curves of the neutrophil percentage values of TW and BALF were created to determine the optimal cutoff values and to calculate the diagnostic Se and Sp for diagnosing airway inflammation in horses with and without clinical respiratory signs. The Se and Sp of TW and BALF neutrophil percentages were further estimated using a two-test one-population Bayesian latent class model. The two tests showed substantial agreement, and only 17.5% of the horses were classified differently (healthy vs. diseased). The neutrophil percentage was found to correlate between TW and BALF. The Se and Sp of TW were generally higher than for BAL when estimated with area under the curve or Bayesian model. Cutoff values of 17.7% for TW and 7% for BALF were indicated by the ROCs. We conclude that TW is a more sensitive and specific method in our patient population. We suggest that the current neutrophil cutoff values of 20% for TW and 5% for BALF would still be appropriate to use in clinical diagnosis of airway inflammation. However, further studies with other cell types and in other populations are warranted to determine the best sampling method for individual horses.

Reflux aspiration in lungs of dogs with respiratory disease and in healthy West Highland White Terriers.

BACKGROUND: Gastroesophageal reflux and microaspiration (MA) of gastric juice are associated with various human respiratory diseases but not in dogs. OBJECTIVE: To detect the presence of bile acids in bronchoalveolar lavage fluid (BALF) of dogs with various respiratory diseases. ANIMALS: Twenty-seven West Highland White Terriers (WHWTs) with canine idiopathic pulmonary fibrosis (CIPF), 11 dogs with bacterial pneumonia (BP), 13 with chronic bronchitis (CB), 9 with eosinophilic bronchopneumopathy (EBP), 19 with laryngeal dysfunction (LD), 8 Irish Wolfhounds (IWHs) with previous BPs, 13 healthy WHWTs, all privately owned dogs, and 6 healthy research colony Beagles METHODS: Prospective cross-sectional observational study with convenience sampling of dogs. Bile acids were measured by mass spectrometry in BALF samples. Total bile acid (TBA) concentration was calculated as a sum of 17 different bile acids. RESULTS: Concentrations of TBA were above the limit of quantification in 78% of CIPF, 45% of BP, 62% of CB, 44% of EBP, 68% of LD, and 13% of IWH dogs. In healthy dogs, bile acids were detected less commonly in Beagles (0/6) than in healthy WHWTs (10/13). Concentrations of TBA were significantly higher in CIPF (median 0.013 µM, range not quantifiable [n.q.]-0.14 µM, P < .001), healthy WHWTs (0.0052 µM, n.q.-1.2 µM, P = .003), LD (0.010 µM, n.q.-2.3 µM, P = .015), and CB (0.0078 µM, n.q.-0.073 µM, P = .018) groups compared to Beagles (0 µM, n.q.). CONCLUSION AND CLINICAL IMPORTANCE: These results suggest that MA occurs in various respiratory diseases of dogs and also in healthy WHWTs.

Expression of extracellular matrix metalloproteinase inducer and matrix metalloproteinase-2 and -9 in horses with chronic airway inflammation.

OBJECTIVE To examine whether expression of extracellular matrix metalloproteinase inducer (EMMPRIN) can be detected in equine lungs and whether it correlates with matrix metalloproteinase (MMP)-2 and -9 expression in bronchoalveolar lavage fluid (BALF) of horses with chronic inflammation of the lungs (ie, lower airway inflammation [LAI]). ANIMALS 29 horses with signs of chronic respiratory tract disease, which were classified as the LAI (n = 17) and LAI with respiratory distress (RDLAI [12]) groups, and 15 control horses. PROCEDURES BALF, tracheal aspirate, and blood samples were obtained, and EMMPRIN expression was determined from BALF cells and RBCs by use of western blotting. Activities of MMP-2 and -9 were determined with zymography. RESULTS Expression of EMMPRIN protein was identified in BALF cells of all horses. Expression of EMMPRIN protein was highest for the RDLAI group and was correlated with MMP-2 and -9 protein expression, MMP-9 gelatinolytic activity, and airway neutrophilia. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that EMMPRIN was involved in the pathophysiologic processes of asthma in horses. However, additional studies of horses and other species are warranted to elucidate the regulation of EMMPRIN expression in asthmatic lungs.

Comparison of submaximal exercise test results and severity of brachycephalic obstructive airway syndrome in English bulldogs.

Canine brachycephalic obstructive airway syndrome (BOAS) is a complex respiratory disease related to congenitally flattened facial and skull anatomy. BOAS causes respiratory distress, heat and exercise intolerance, and gastrointestinal signs. English bulldogs (EB) have a high prevalence of BOAS. Currently, the severity of BOAS signs in veterinary practice is assessed subjectively. To reduce BOAS in brachycephalic breeds, an objective and easy-to-use tool could help breeders select healthier animals. Exercise tests, such as the 6 min walk test (distance walked measured) or the 1000 m walk test (duration measured), could be used to assess the severity of BOAS, as exercise intolerance and impaired recovery are key features of BOAS. This study evaluated the severity of signs and anatomic components of BOAS in a group of prospectively recruited young adult EBs (n = 28) and investigated the correlations of the 6 min walk test or the 1000 m walk test with a veterinary assessment of BOAS severity, using an ordinal 4 level scale of respiratory signs. EBs with more severe BOAS walked a shorter distance, more slowly and their recovery from exercise took longer than those with only mild signs of BOAS. Control dogs of different breeds (n = 10) performed the exercise tests significantly better (i.e. longer distance, faster time and recovery) than EBs. Increases in body temperature during exercise were significantly higher in EBs than in controls. The results of this study support the use of exercise tests for objective evaluation of the severity of BOAS in EBs.