Evaluation of a risk-screening questionnaire to detect equine lung inflammation: Results of a large field study
Article first published online: 25 JUN 2010
© 2010 EVJ Ltd
Equine Veterinary Journal
Volume 43, Issue 2, pages 145–152, March 2011
How to Cite
WASKO, A. J., BARKEMA, H. W., NICOL, J., FERNANDEZ, N., LOGIE, N. and LÉGUILLETTE, R. (2011), Evaluation of a risk-screening questionnaire to detect equine lung inflammation: Results of a large field study. Equine Veterinary Journal, 43: 145–152. doi: 10.1111/j.2042-3306.2010.00150.x
- Issue published online: 24 FEB 2011
- Article first published online: 25 JUN 2010
- [Paper received for publication 03.03.10; Accepted 08.04.10]
- lung inflammation;
- risk-screening questionnaire;
- bronchoalveolar lavage cytology
Reasons for performing study: The diagnosis of equine recurrent airway obstruction (RAO) and inflammatory airway disease (IAD) is based on clinical signs and increased inflammatory cell percentages in the bronchoalveolar lavage (BAL) fluid. Since a BAL is an invasive procedure, a risk-screening questionnaire (RSQ) would be a valuable screening tool for lung inflammation.
Objective: To evaluate the accuracy of a RSQ to detect lower airway inflammation (LAI) in a large population of horses.
Methods: A standardised BAL was performed in the field on 167 horses in Alberta, Canada. Horses were separated into 3 categories: 1) BAL normal; 2) BAL mild to moderate LAI (MLAI), and 3) BAL severe LAI (SLAI). The horse owners were asked to complete a RSQ. The RSQ scores were compared to the BAL results to determine the likelihood of a horse having MLAI, SLAI or no LAI.
Results: Based on BAL cytology, 28 (17%) horses were normal and 139 (83%) were abnormal, with 110 (66%) showing MLAI and 29 (17%) SLAI. Horses with SLAI and MLAI had a mean RSQ score of 0.95 and 0.70, respectively, compared to 0.60 for normal BAL horses. Horses with SLAI showed more clinical signs than normal and MLAI horses. The sensitivity and negative predictive values of the RSQ for detecting SLAI using a cut-off score of 0.87, were excellent at 0.90 (95%CI 0.73–0.98) and 0.96 (95%CI 0.82–1.00). Questions on the clinical signs typically found in RAO cases differed significantly between horses with BAL SLAI and those with BAL normal.
Conclusions: Prevalence of MLAI was high in this population. Although the RSQ did not allow differentiating normal horses from horses with MLAI, it has a high sensitivity to detect horses with SLAI and is therefore a good screening tool for SLAI.