Journal of Veterinary Emergency and Critical Care

Early View e13475

RETROSPECTIVE STUDY

Evaluation of Neutrophil-to-Lymphocyte Ratio as a Diagnostic Marker in Dogs With Bacterial Pneumonia

Morgan Alexandra Stark,

Corresponding Author

Morgan Alexandra Stark

[email protected]

orcid.org/0000-0001-8650-6536

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Writing - original draft, Writing - review & editing

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Paula M. Simons,

Paula M. Simons

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Data curation, Methodology, Writing - review & editing

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Bridget Mary Lyons,

Bridget Mary Lyons

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Formal analysis, Supervision, Methodology, Writing - review & editing

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Morgan Alexandra Stark,

Corresponding Author

Morgan Alexandra Stark

[email protected]

orcid.org/0000-0001-8650-6536

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Writing - original draft, Writing - review & editing

Search for more papers by this author

Paula M. Simons,

Paula M. Simons

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Data curation, Methodology, Writing - review & editing

Search for more papers by this author

Bridget Mary Lyons,

Bridget Mary Lyons

Department of Emergency and Critical Care, Cornell University Veterinary Specialists, Stamford, Connecticut, USA

Contribution: Conceptualization, Formal analysis, Supervision, Methodology, Writing - review & editing

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First published: 08 July 2025

https://doi.org/10.1111/vec.13475

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ABSTRACT

Objective

To determine the ability of the blood neutrophil-to-lymphocyte ratio (NLR) to differentiate between bacterial pneumonia and nonbacterial pneumonia in dogs undergoing airway sampling.

Design

Retrospective study.

Setting

A university teaching hospital and affiliated private practice specialty hospital.

Animals

Forty-one client-owned dogs undergoing airway sampling with CBCs performed within 48 h of collecting airway lavage samples between January 2018 and December 2022.

Interventions

None.

Measurements and Main Results

Medical records were reviewed and the following parameters were recorded: signalment, length of hospitalization, WBC count, neutrophil count, lymphocyte count, type of airway sampling, airway cytology and culture results, timing of antimicrobial use, radiographic findings, concurrent diseases, final diagnosis, and outcome. Patients that received corticosteroids or had hematological neoplasia were excluded. Of the 41 dogs included, 51.2% (21/41) were diagnosed with bacterial pneumonia. Twenty-three patients (56.1%) received antimicrobials before airway lavage, and 11 (47.8%) of these dogs were diagnosed with bacterial pneumonia. Of the 18 patients (43.9%) that did not receive antimicrobials before airway lavage, 10 (55.6%) were diagnosed with bacterial pneumonia. One dog (2.4%) underwent a transtracheal wash, 16 (39%) underwent a bronchoalveolar lavage, and 24 (58.5%) underwent an endotracheal wash. NLR was not significantly associated with bacterial pneumonia (P = 0.248). In dogs with bacterial pneumonia, NLR was not associated with mortality (P = 0.454) or length of hospital stay (LOS) (P = 0.282). NLR was positively associated with LOS when all dogs were analyzed together (P = 0.042).

Conclusions

NLR was not different in dogs with bacterial pneumonia than in dogs without bacterial pneumonia. NLR was positively associated with LOS when all dogs were included in the analysis (P = 0.042).

Conflicts of Interest

The authors declare no conflicts of interest.

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Early View

Online Version of Record before inclusion in an issue

e13475

Evaluation of Neutrophil-to-Lymphocyte Ratio as a Diagnostic Marker in Dogs With Bacterial Pneumonia

ABSTRACT

Objective

Design

Setting

Animals

Interventions

Measurements and Main Results

Conclusions

Conflicts of Interest

References

References

Information

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Evaluation of Neutrophil-to-Lymphocyte Ratio as a Diagnostic Marker in Dogs With Bacterial Pneumonia

ABSTRACT

Objective

Design

Setting

Animals

Interventions

Measurements and Main Results

Conclusions

Conflicts of Interest

References

References

Related

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