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Home / Equine Research Bank / Equine Vet J / Endoscopically assessed mucus parameters in equine asthma: R...
Equine veterinary journal2025; doi: 10.1111/evj.70002

Endoscopically assessed mucus parameters in equine asthma: Relationship to clinical history and cytological findings data.

Abstract: Mucus parameters are hallmark diagnostic features of equine asthma (EA). Objective: To investigate the relationship between mucus quantity score and mucus viscosity score with signalment, history, clinical findings and cytological parameters. Methods: Retrospective cross-sectional study. Methods: Mucus quantity and viscosity scores, signalment, history and clinical findings recorded for diagnostic purposes from up to 1599 samples, and cytological values of the corresponding bronchoalveolar lavage fluid (BALF) and tracheobronchial secretions were analysed. The cut-off value of a mucus quantity score >2 for the diagnosis of mild to moderate EA (MEA) was used to calculate the odds ratios for MEA and severe EA (SEA). Associations were tested via a multivariate Kruskal-Wallis test. The mucus scores were analysed pairwise with cytological characteristics, anamnestic data and clinical signs by testing for independence using the chi-square test. Correlations were evaluated using the non-parametric Spearman's rank correlation coefficient. Results: A mucus quantity score >2 was associated with increased odds of diagnosing SEA (odds ratio 3.6, 95% confidence interval 1.75, 7.17, p < 0.001), but not for MEA. A weak positive correlation was found between neutrophil granulocytes in BALF and mucus quantity score (rho: 0.353, p < 0.001) as well as mucus viscosity score (rho: 0.225, p < 0.001). The mucus scores for quantity and viscosity were significantly associated (p < 0.001) with age, respiratory rate and arterial oxygen partial pressure values, and significantly associated (p < 0.001) with season, type of nasal discharge and respiratory pattern. However, no associations were found with body condition score (BCS), sex and breed. Conclusions: This was a convenience sample with a cytologically unremarkable control group, but no healthy control group. Conclusions: Mucus quantity score is a diagnostic parameter for the diagnosis of SEA. Associations between mucus scores and neutrophilic influx and with some clinical parameters were identified, while there was no confirmed relationship to BCS. Unassigned: Schleimparameter sind charakteristische Merkmale und indikative diagnostische Komponenten von Equinem Asthma (EA). Unassigned: Querschnittsstudie zur Untersuchung der Verhähltnisse zwischen dem Mucus Quantity Score (m.q.) und dem Mucus Viscosity Score (m.v.) und Signalement, Anamnese, klinischen Befunden und zytologischen Parametern. Methods: Retrospektive Querschnittsstudie. Methods: Analysiert wurden die Schleimmenge und Viskositätswerte, das Signalement, die Anamnese und klinischen Befunde, die zu Diagnosezwecken von bis zu 1599 Proben erfasst wurden, sowie die zytologischen Werte der entsprechenden bronchoalveolären Lavagflüssigkeit (BALF) und tracheobronchialen Sekrete (TBS). Der Cut‐off‐Wert eines Mucus Quantity Score >2 für die Diagnose eines leichten bis mittelschweren EA (MEA) wurde für die Berechnung der Odds Ratios für MEA und schweres EA (SEA) verwendet. Assoziationen wurden mittels eines multivariaten Kruskall‐Wallis‐Tests geprüft. Die Mucus‐Scores wurden paarweise mit zytologischen Merkmalen, anamnestischen Daten und klinischen Symptomen analysiert, indem die Unabhängigkeit mit dem Chi‐Square‐Test geprüft wurde. Korrelationen wurden mit dem nichtparametrischen Spearman‐Rangkorrelationskoeffizienten bewertet. Unassigned: Ein Mucus Quantity Score > 2 war mit einer 3,6‐fachen [OR 3,6, 95% 1,75, 7,17, p < 0,001] statistisch signifikant erhöhten Wahrscheinlichkeit verbunden, ein SEA zu diagnostizieren, aber nicht für ein MEA. Eine schwache positive Korrelation wurde zwischen neutrophilen Granulozyten in der BALF und des Mucus Quantity Score (rho: 0,353; p < 0,001) sowie dem Mucus Viscosity Score (rho: 0,225; p < 0,001) festgestellt. Darüber hinaus waren die Schleimwerte Mucus Quantity Score und Mucus Viscosity Score signifikant (p < 0,001) mit Alter, Atemfrequenz und arteriellen Sauerstoffpartialdruckwerten sowie signifikant (p < 0,001) mit Jahreszeit, Art des Nasenausflusses und Atmungsmuster verbunden. Es wurden jedoch keine Zusammenhänge mit dem Body Condition Score (BCS), dem Geschlecht und der Rasse festgestellt. HAUPTEINSCHRÄNKUNGEN: Es handelte sich um eine Zufallsstichprobe mit einer “zytologisch unauffälligen” Kontrollgruppe, aber ohne eine gesunke Kontrollgruppe. Unassigned: Der Mucus Quantity Score ist ein diagnosticher Parameter für die Diagnose von SEA. Aossiziationen zwischen Mucus‐Scores und neutrophilem Einstrom sowie manchen klinischen Parametern wurden identifiziert, während eine Beziehung zum BCS nicht bestätigt werden konnte.
© 2025 The Author(s). Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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Publication Date: 2025-07-24 PubMed ID: 40704584DOI: 10.1111/evj.70002Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research investigates the relationship between mucus parameters, such as quantity and viscosity, and various factors such as history, clinical findings, and cytological parameters in horses diagnosed with equine asthma. The study finds that higher mucus quantity scores are associated with diagnosing severe equine asthma, neutrophilic influx and several clinical parameters. However, they found no association with the animal’s body condition score, sex, and breed.

Objective and Methods

  • The goal of the study was to analyse the connection between mucus quantity and viscosity scores with signalment, history, clinical findings, and cytological parameters in horses diagnosed with equine asthma (EA).
  • The researchers conducted a retrospective cross-sectional study and worked on data from up to 1599 samples, extracted for diagnostic purposes.
  • The samples included mucus score, signalment, history, and clinical findings, as well as cytological values of the corresponding bronchoalveolar lavage fluid (BALF) and tracheobronchial secretions.

Analysis and Results

  • Analysis was done using the multivariate Kruskal-Wallis test, chi-square test for independence, and Spearman’s rank correlation coefficient.
  • The mucus quantity score >2 showed increased odds of diagnosing severe EA (SEA), indicating that high mucus quantity was indicative of severe asthma conditions.
  • A weak positive link was observed between the quantity and viscosity of mucus and the presence of neutrophil granulocytes in BALF.
  • Furthermore, mucus quantity and viscosity scores were significantly related to age, respiratory rate, and arterial oxygen partial pressure values, along with the type of nasal discharge, respiratory pattern, and season.
  • However, no relationship was established with the body condition score, sex, and breed of the horse.

Limitations and Conclusions

  • The study was based on a convenience sample and did not include a healthy control group.
  • This study concludes that mucus quantity is an important diagnostic parameter for severe EA.
  • Associations were confirmed between mucus scores and neutrophilic influx as well as some clinical parameters. But, there was no confirmed relationship with the body condition score.

Cite This Article

APA
Drespling J, Berwanger L, Kühn H, Schwarz B, Doherr M, Mundhenk L. (2025). Endoscopically assessed mucus parameters in equine asthma: Relationship to clinical history and cytological findings data. Equine Vet J. https://doi.org/10.1111/evj.70002

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Drespling, Julia
  • Institute of Veterinary Pathology, Freie Universität Berlin, Berlin, Germany.
  • EquiZyt UG Laboratory, Steinhöring, Germany.
Berwanger, Leonie
  • Institute of Veterinary Epidemiology and Biostatistics, Freie Universität Berlin, Berlin, Germany.
Kühn, Heike
  • EquiZyt UG Laboratory, Steinhöring, Germany.
Schwarz, Bianca
  • EquiZyt UG Laboratory, Steinhöring, Germany.
Doherr, Marcus
  • Institute of Veterinary Epidemiology and Biostatistics, Freie Universität Berlin, Berlin, Germany.
Mundhenk, Lars
  • Institute of Veterinary Pathology, Freie Universität Berlin, Berlin, Germany.

Grant Funding

  • MU 3015/3-1 / Deutsche Forschungsgemeinschaft

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