Flood J A, Collins N M, Russell C M, Cuming R S, Carrick J B, Cudmore L A
Scone Equine Hospital, 406 Bunnan Road, Scone, New South Wales, Australia.
Equine Specialist Consulting, Kingdon Street, Scone, New South Wales, Australia.
Aust Vet J. 2025 Apr;103(4):163-170. doi: 10.1111/avj.13423. Epub 2025 Jan 28.
Sepsis is a leading cause of morbidity and mortality in neonatal foals. Administration of appropriate antimicrobials and early aggressive supportive treatment is central to the efficacious treatment of neonatal sepsis and has proven to positively influence outcomes. The primary aim of our study was to evaluate microorganism results and antimicrobial sensitivities of neonatal foals with a positive blood culture submitted to our intensive care unit (ICU) during 2005-2022. The secondary aim was to compare the results to those of a similar previous study performed at the same ICU during 1999-2004.
Retrospective analysis of bacterial blood culture results from neonatal foals ≤7 days of age admitted to Scone Equine Hospital between 2005 and 2022 was analysed. Samples were collected at admission. Antimicrobial sensitivity testing was assessed using the Kirby-Bauer disc diffusion method. Susceptibility results from the two study periods were compared using Fisher's exact tests. Statistical significance was achieved at P value <0.05.
From 1621 blood cultures submitted, 380 returned a positive result (380/1621; 23.4%). A total of 402 bacterial isolates were recovered: 55.5% Gram-positive isolates (223/402), 42.6% Gram-negative isolates (171/402) and 1.7% anaerobic isolates (7/409). A significant increase in Gram-positive isolates between time periods was observed (P = 0.002). Gram-negative isolates had significant increases of resistance in seven out of nine antimicrobials tested.
This study provides Australian veterinarians with information on common bacterial pathogens in critically ill neonatal foals to assist with making informed empirical antimicrobial choices to optimise treatment efficacy. Increases in bacterial resistance to commonly administered antimicrobials were observed; therefore, culture and sensitivity testing should guide antimicrobial choices. Judicious use of antimicrobials in equine practice is imperative.
脓毒症是新生马驹发病和死亡的主要原因。使用适当的抗菌药物和早期积极的支持性治疗是有效治疗新生马驹脓毒症的核心，并且已被证明对治疗结果有积极影响。我们研究的主要目的是评估2005年至2022年期间入住我们重症监护病房（ICU）且血培养呈阳性的新生马驹的微生物检测结果和抗菌药敏情况。次要目的是将结果与1999年至2004年期间在同一ICU进行的一项类似先前研究的结果进行比较。
对2005年至2022年期间入住斯昆马医院的7日龄及以下新生马驹的细菌血培养结果进行回顾性分析。样本在入院时采集。采用 Kirby-Bauer 纸片扩散法评估抗菌药敏试验。使用Fisher精确检验比较两个研究时期的药敏结果。P值<0.05时具有统计学意义。
在提交的1621份血培养样本中，380份结果呈阳性（380/1621；23.4%）。共分离出402株细菌：55.5%为革兰氏阳性菌（223/402），42.6%为革兰氏阴性菌（171/402），1.7%为厌氧菌（7/409）。观察到不同时期革兰氏阳性菌分离株显著增加（P = 0.002）。在所测试的9种抗菌药物中，革兰氏阴性菌分离株对其中7种的耐药性显著增加。
本研究为澳大利亚兽医提供了有关危重新生马驹常见细菌病原体的信息，以帮助做出明智的经验性抗菌药物选择，从而优化治疗效果。观察到细菌对常用抗菌药物的耐药性增加；因此，培养和药敏试验应指导抗菌药物选择。在马科动物医疗实践中必须谨慎使用抗菌药物。
