(C41) Neutrophil-to-Lymphocyte, Monocyte-to-Lymphocyte, and Platelet-to-Lymphocyte Ratios as Inflammatory Biomarkers in Dogs with Myxomatous Mitral Valve Disease

Abstract:

Background: In humans, neutrophilia is linked to the development of acute heart failure, and lymphopenia is associated with poor prognosis. The neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) are newly proposed inflammatory biomarkers. As MMVD is the most common acquired heart disease in dogs, evaluation of inflammatory biomarkers is needed.

Objectives: To investigate NLR, MLR, and PLR in dogs with MMVD.

Animals: In total, 106 dogs with MMVD and 22 healthy dogs were included in the study.

Methods: Complete blood count data were obtained retrospectively, and NLR, MLR, and PLR were compared between dogs with MMVD and healthy dogs.

Results: NLR and MLR were significantly higher in dogs with MMVD C and D (NLR of 4.99 [3.69–7.27]; MLR of 0.56 [0.36–0.74]) than in healthy dogs (NLR: 3.05 [1.82–3.37], P < 0.001; MLR: 0.21 [0.14–0.32], P < 0.001), MMVD stage B1 (NLR: 3.15 [2.15–3.86], P < 0.001; MLR: 0.26 [0.20–0.36], P < 0.001), and MMVD stage B2 dogs (NLR: 3.22 [2.45–3.85], P < 0.001; MLR: 0.30 [0.19–0.37], P < 0.001). The area under the receiver operating characteristic curves of the NLR and MLR to distinguish dogs with MMVD C and D from those with MMVD B were 0.84 and 0.89, respectively. The optimal cutoff value for NLR was 4.296 (sensitivity, 68%; specificity, 83.95%), and the MLR value was 0.322 (sensitivity, 96%; specificity, 66.67%).

Conclusions and Clinical importance: NLR and MLR can be used as adjunctive indicators of CHF in dogs.