Secombe C J, van Eps A W, Bruce M, Lester G D
School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia.
Equine Specialist Hospital, School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Aust Vet J. 2019 Sep;97(9):343-350. doi: 10.1111/avj.12861. Epub 2019 Jul 8.
To investigate the relationship between bronchoalveolar lavage fluid cytology, particularly mast cells, and airway hyper-reactivity in athletic horses presented for poor performance that included a respiratory tract evaluation in two disparate locations in Australia.
Multi-centre, retrospective and prospective cross-sectional study METHODS: Eighty four adult horses underwent both pulmonary function testing and histamine bronchoprovocation with a commercial flowmetric plethysmography system. A bronchoalveolar lavage was performed four to twelve hours later. Bronchoalveolar lavage fluid cytology was categorised using two differing classification systems to define mild equine asthma. Statistical analysis was used to assess associations between bronchoalveolar lavage fluid relative inflammatory cell percentages, and airway hyper-reactivity and their associated categorisations.
Sixty four percent (54/84) of horses displayed airway hyper-reactivity, as defined by PC < 6 mg/ml of histamine. A relative mastocytosis was the most common bronchoalveolar lavage fluid cytological abnormality. Horses with a sole mast cell response of ≥ 5% within their bronchoalveolar lavage fluid displayed airway hyper-reactivity at a lower dose of nebulized histamine than horses with normal bronchoalveolar lavage fluid cytology. Horses with mixed cell responses (relative mast cell percentage > 2% and/or relative neutrophil percentage > 5% and/or eosinophil relative cell percentage ≥ 1%) displayed airway hyper-reactivity at a lower dose of nebulized histamine than horses with normal bronchoalveolar lavage fluid cytology.
In the Australian context, recently revised increased bronchoalveolar lavage fluid cytology relative cell percentage cut offs appear appropriate for sole mast cell responses. The historical lower cut offs appear to be appropriate for mixed inflammatory cell responses.
研究支气管肺泡灌洗（BAL）液细胞学，尤其是肥大细胞，与表现不佳的运动马匹气道高反应性之间的关系，这些马匹在澳大利亚两个不同地点进行了呼吸道评估。
多中心、回顾性和前瞻性横断面研究
84匹成年马使用商用流量容积描记系统进行了肺功能测试和组胺支气管激发试验。4至12小时后进行支气管肺泡灌洗。使用两种不同的分类系统对支气管肺泡灌洗液细胞学进行分类，以定义轻度马哮喘。采用统计分析评估支气管肺泡灌洗液相对炎症细胞百分比、气道高反应性及其相关分类之间的关联。
64%（54/84）的马匹表现出气道高反应性，定义为组胺PC＜6mg/ml。相对肥大细胞增多是最常见的支气管肺泡灌洗液细胞学异常。支气管肺泡灌洗液中肥大细胞单一反应≥５%的马匹，与支气管肺泡灌洗液细胞学正常的马匹相比，雾化组胺剂量较低时即表现出气道高反应性。具有混合细胞反应（相对肥大细胞百分比＞2%和/或相对中性粒细胞百分比＞5%和/或嗜酸性粒细胞相对细胞百分比≥1%）的马匹，与支气管肺泡灌洗液细胞学正常的马匹相比，雾化组胺剂量较低时即表现出气道高反应性。
在澳大利亚的背景下，最近修订的支气管肺泡灌洗液细胞学相对细胞百分比临界值升高似乎适用于肥大细胞单一反应。历史上较低的临界值似乎适用于混合炎症细胞反应。
