Selected inflammatory markers in uterine and peripheral blood of bitches with pyometra

Kinga Domrazek; Szymon Kanafa; Magdalena Krzeszewska Zachary; Roman Dąbrowski; Lourdes Soler; Piotr Jurka

doi:10.2478/jvetres-2026-0014

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Selected inflammatory markers in uterine and peripheral blood of bitches with pyometra

Journal of Veterinary Research

Volume 70 (2026): Issue 1 (March 2026)

By: Kinga Domrazek , Szymon Kanafa , Magdalena Krzeszewska Zachary , Roman Dąbrowski , Lourdes Soler and Piotr Jurka

Open Access

|Mar 2026

Abstract

Introduction

Pyometra is a common and potentially life-threatening uterine infection in bitches, with severe local and systemic inflammation as symptoms. Studies exist on inflammatory markers in peripheral blood (PB), but little is known about their expression in uterine blood (UB). This study aimed to compare their concentrations simultaneously in UB and PB of bitches with pyometra, and to evaluate their diagnostic and prognostic potential.

Material and Methods

Twenty-two bitches with confirmed pyometra (13 closed-cervix and 9 open-cervix cases) and six healthy controls were enrolled. Blood samples were collected from the cephalic and uterine veins during ovariohysterectomy. The concentrations of IL-1α, IL-1β, IL-6 and IL-10 were measured using an ELISA validated for dogs, and C-reactive protein (CRP) was measured by an immunoturbidimetric assay. These five inflammatory markers were compared statistically between the three groups of dogs and two types of blood sample using the Mann–Whitney U and Wilcoxon tests.

Results

All markers were significantly elevated in affected bitches’ UB and PB. The IL-6 concentrations were significantly higher in UB than in PB, suggesting local production of this cytokine. Conversely, the IL-10 levels were higher in PB, possibly reflecting a systemic regulatory response. The concentrations of IL-1α and IL-1β differed insignificantly from each other. Those of CRP were significantly higher in open-cervix than in closed-cervix pyometra, indicating a stronger acute-phase response.

Conclusion

The results assign IL-6 and CRP a potential role as biomarkers for the diagnosis and prognosis of pyometra. Simultaneous analysis of uterine and systemic inflammatory responses provides insight into the disease’s pathophysiology and may support more targeted therapeutic approaches.

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Articles in this issue

DOI: https://doi.org/10.2478/jvetres-2026-0014 | Journal eISSN: 2450-8608

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Language: English

Page range: 129 - 137

Submitted on: Jun 30, 2025

Accepted on: Mar 5, 2026

Published on: Mar 12, 2026

Published by: National Veterinary Research Institute in Pulawy

In partnership with: Paradigm Publishing Services

Publication frequency: 4 issues per year

Keywords:

bitch,

interleukin,

local and systemic inflammation,

pyometra cervical patency

Related subjects:

Life sciences,

Molecular biology,

Microbiology and virology,

Life sciences, other,

Medicine,

Veterinary medicine

© 2026 Kinga Domrazek, Szymon Kanafa, Magdalena Krzeszewska Zachary, Roman Dąbrowski, Lourdes Soler, Piotr Jurka, published by National Veterinary Research Institute in Pulawy
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 70 (2026): Issue 1 (March 2026)