Biophysical properties of alveolar surfactant in drever dogs with hunting associated pulmonary edema

TL;DR

This study found that alveolar surfactant function is normal in drever dogs with hunting-related pulmonary edema, suggesting the condition is not caused by surfactant dysfunction.

Contribution

The study provides new evidence that surfactant dysfunction is not the cause of hunting-associated pulmonary edema in drever dogs.

Findings

No significant differences in surfactant biophysical properties were found between healthy and affected drever dogs.

Surfactant's ability to reduce surface tension during compression was similar in both groups.

The results suggest that surfactant dysfunction is not responsible for the observed pulmonary edema in drever dogs.

Abstract

A syndrome of acute non-cardiogenic pulmonary edema associated with hunting is prevalent in the drever breed, but etiology of this syndrome is currently unknown. Alveolar surfactant has a critical role in preventing alveolar collapse and edema formation. The aim of this study was to investigate, whether the predisposition to hunting associated pulmonary edema in drever dogs is associated with impaired biophysical properties of alveolar surfactant. Seven privately owned drever dogs with recurrent hunting associated pulmonary edema and seven healthy control dogs of other breeds were included in the study. All affected dogs underwent thorough clinical examinations including echocardiography, laryngeal evaluation, bronchoscopy, and bronchoalveolar lavage (BAL) as well as head, neck and thoracic computed tomography imaging to rule out other cardiorespiratory diseases potentially causing the clinical signs. Alveolar surfactant was isolated from frozen, cell-free supernatants of BAL fluid and biophysical analysis of the samples was completed using a constrained sessile drop surfactometer. Statistical comparisons over consecutive compression expansion cycles were performed using repeated measures ANOVA and comparisons of single values between groups were analyzed using T-test.

There were no significant differences between groups in any of the biophysical outcomes of surfactant analysis. The critical function of surfactant, reducing the surface tension to low values upon compression, was similar between healthy dogs and affected drevers.

The etiology of hunting associated pulmonary edema in drever dogs is not due to an underlying surfactant dysfunction.

The online version contains supplementary material available at 10.1186/s13028-024-00745-x.

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