Long-term outcome and use of 6-minute walk test in West Highland White Terriers with idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is an incurable interstitial lung disease occurring mainly in West Highland White Terriers (WHWTs). The effects of IPF on survival and on exercise tolerance in WHWTs are unknown. OBJECTIVES: To evaluate survival, prognostic factors, and exercise tolerance in WHWTs with IPF. ANIMALS: Privately owned WHWTs; 15 with IPF and 11 healthy controls. METHODS: Prospective case-control study conducted in 2007-2012. For survival, descriptive statistics and Kaplan-Meier (KM) survival curves with Cox proportional hazard ratios were performed. For the prognostic factor study, KM curves, Cox regression analysis, and logistic regression models were used. The 6-minute walk test (6MWT) was used for measurement of exercise tolerance. RESULTS: The median IPF-specific survival of deceased WHWTs (7/15) with IPF was 32 (range 2-51) months from onset of clinical signs. The risk of death from birth in WHWTs with IPF in age-adjusted Cox model was significantly higher (hazard ratio 4.6; 95% confidence interval 1.05-19.74, P = .04) than in control WHWTs. No significant prognostic factors were identified. In 6MWT, WHWTs with IPF walked a shorter distance, median 398 m (range 273-519 m), than healthy controls, median 492 m (420-568 m), P = .05, and the partial pressure of oxygen in arterial blood in diseased dogs had a moderate positive correlation with walking distance (Kendall's tau-b = 0.69, P = .06). CONCLUSION AND CLINICAL IMPORTANCE: IPF had a negative impact on life expectancy, but individual survival varied considerably. 6MWT proved to be a well-tolerated, noninvasive test to evaluate exercise tolerance.

Serum C-reactive protein as a diagnostic biomarker in dogs with bacterial respiratory diseases.

BACKGROUND: C-reactive protein (CRP) is a major acute-phase protein in dogs. Serum concentrations are low in healthy animals, but increase rapidly after inflammatory stimuli. OBJECTIVE: The aim of the study was to investigate CRP concentrations in various respiratory diseases of dogs and to determine if CRP can be used as a biomarker in the diagnosis of bacterial respiratory diseases. ANIMALS: A total of 106 privately owned dogs with respiratory diseases (17 with bacterial tracheobronchitis [BTB], 20 with chronic bronchitis [CB], 20 with eosinophilic bronchopneumopathy [EBP], 12 with canine idiopathic pulmonary fibrosis [CIPF], 15 with cardiogenic pulmonary edema [CPE], and 22 with bacterial pneumonia [BP]) and 72 healthy controls. METHODS: The study was conducted as a prospective cross-sectional observational study. CRP was measured in serum samples. Diagnosis was confirmed by clinical and laboratory findings, diagnostic imaging, and selected diagnostic methods such as cytological and microbiological analysis of respiratory samples, echocardiography, and histopathology. RESULTS: Dogs with BP had significantly higher CRP concentrations (median, 121 mg/L; interquartile range, 68-178 mg/L) than dogs with BTB (23, 15-38, P = .0003), CB (13, 8-14, P < .0001), EBP (5, 5-15, P < .0001), CIPF (17, 10-20, P < .0001), or CPE (19, 13-32, P < .0001) and healthy controls (14, 8-20, P < .0001). Dogs with BTB had significantly higher CRP concentrations than dogs with CB (P = .001) or EBP (P < .0001) and healthy controls (P = .029). CONCLUSION AND CLINICAL IMPORTANCE: These results indicate that CRP has potential for use as an additional biomarker, especially in the diagnostics of BP.