BACKGROUND Horses with bacterial sinusitis frequently undergo empirical treatment with antimicrobials, however, in some cases bacterial culture of the affected sinus is used to direct therapy. Data regarding which organisms are part of the commensal microbiota of the equine sinus are lacking making it difficult to interpret culture results and guide empiric antimicrobial selection. OBJECTIVES Our objectives were to describe the bacterial and fungal microbiota of the paranasal sinuses in clinically normal horses using culture-dependent and independent approaches and to compare the bacterial culture and susceptibility patterns of normal horses with those from horses affected with primary and secondary sinusitis. STUDY DESIGN Experimental study and descriptive retrospective review of case records. METHODS Sinus washes were collected from 23 healthy horses. Washes were submitted for routine culture and susceptibility testing and DNA was isolated for next generation sequencing of bacterial and fungal marker genes. For clinical cases of sinusitis, medical records from 2010 to 2017 were reviewed and horses diagnosed with primary and/or secondary sinusitis were included. RESULTS The paranasal sinus cavity hosts multiple bacterial and fungal organisms. The bacterial microbiota of healthy horses consists largely of uncultivable, aerobic bacteria. While few anaerobes were isolated from normal horses, the majority of clinical cases resulted in growth of anaerobic organisms with no difference in the proportion of aerobic and anaerobic bacteria isolated from clinical cases. MAIN LIMITATIONS Small sample size in both populations of horses and heterogeneity of the population prevent a more in-depth analysis. CONCLUSIONS The microbiota of the paranasal sinuses of horses consists primarily of aerobic bacteria and fungal organisms, the majority of which are uncultivable via common clinical methods. Anaerobic bacteria are found in the majority of horses with clinical sinusitis. These findings suggest anaerobic bacteria are associated with sinusitis and their presence should be considered when treating horses with sinusitis.

中文翻译：

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马鼻窦微生物群在健康和疾病中的培养独立和依赖性评估。

背景技术患有细菌性鼻窦炎的马经常用抗微生物剂进行经验性治疗，然而，在某些情况下，受影响鼻窦的细菌培养物被用于指导治疗。缺乏关于哪些微生物是马鼻窦共生微生物群一部分的数据，因此难以解释培养结果和指导经验性抗菌药物选择。目的 我们的目标是使用培养依赖和独立的方法来描述临床正常马鼻窦的细菌和真菌微生物群，并比较正常马与原发性和继发性鼻窦炎马的细菌培养和易感性模式。研究设计 实验研究和病例记录的描述性回顾性审查。方法 从 23 匹健康马收集鼻窦冲洗液。洗涤液用于常规培养和敏感性测试，分离 DNA 用于细菌和真菌标记基因的下一代测序。对于鼻窦炎的临床病例，回顾了 2010 年至 2017 年的医疗记录，并纳入了诊断为原发性和/或继发性鼻窦炎的马。结果 鼻窦腔内有多种细菌和真菌生物。健康马的细菌微生物群主要由不可培养的好氧细菌组成。虽然从正常马中分离出的厌氧菌很少，但大多数临床病例导致厌氧菌生长，从临床病例中分离出的需氧菌和厌氧菌的比例没有差异。主要限制 马群中的小样本量和人口的异质性阻碍了更深入的分析。结论马鼻窦微生物群主要由需氧菌和真菌组成，其中大部分无法通过临床常用方法培养。大多数患有临床鼻窦炎的马都发现了厌氧菌。这些发现表明厌氧菌与鼻窦炎有关，在治疗患有鼻窦炎的马时应考虑它们的存在。大多数患有临床鼻窦炎的马都发现了厌氧菌。这些发现表明厌氧菌与鼻窦炎有关，在治疗患有鼻窦炎的马时应考虑它们的存在。大多数患有临床鼻窦炎的马都发现了厌氧菌。这些发现表明厌氧菌与鼻窦炎有关，在治疗患有鼻窦炎的马时应考虑它们的存在。