Kubai Melissa A, Roy Mackenzie M, Stinman Chloe C, Kenne Danielle E, Allbaugh Rachel A, Sebbag Lionel
Department of Veterinary Clinical Sciences, Iowa State University, College of Veterinary Medicine, Ames, IA, United States.
Veterinary Diagnostic Laboratory, Iowa State University, College of Veterinary Medicine, Ames, IA, United States.
Front Vet Sci. 2024 Jul 12;11:1417842. doi: 10.3389/fvets.2024.1417842. eCollection 2024.
Bacterial keratitis is a common and serious condition that often leads to vision impairment and potential loss of the eye if not treated promptly and adequately. Topical blood products are often used concurrently with topical antibiotics, helping to mitigate corneal 'melt' from proteases released on the ocular surface. However, blood products are rich in albumin and could affect the efficacy of antibiotics due to drug-protein binding. In this study, serum and plasma samples were harvested from 10 healthy dogs and 10 healthy horses, obtaining fresh and frozen (1 month at -20°C) aliquots for experiments. Albumin levels were quantified using species-specific ELISA kits. Thirty bacteria (10 , 10 , 10 ), isolated from canine patients with infectious keratitis, were each tested with blank plates as well as commercial susceptibility plates (Sensititre™ JOEYE2) to assess the minimal inhibitory concentration (MIC) of 17 different antibiotics in the absence (control) or presence of eight test groups: serum or plasma (fresh or frozen) from canines or equines. Albumin concentrations ranged from 13.8-14.6 mg/mL and 25.9-26.5 mg/mL in canine and equine blood products, respectively. A direct antimicrobial effect was observed mostly with equine vs. canine blood products (specifically serum and to a lesser degree plasma), and mostly for isolates. MICs generally increased in the presence of blood products (up to 10.8-fold), although MICs also decreased (down to 0.25-fold) for selected antibiotics and ocular pathogens. Median (range) fold changes in MICs were significantly greater ( = 0.004) with the canine blood products [2 (0.67-8.1)] than the equine blood products [2 (0.5-5)]. In practice, clinicians should consider equine over canine blood products (lesser impact on antimicrobial susceptibility), serum over plasma (greater antimicrobial effects), and administering the blood product ≥15 min following the last antibiotic eyedrop to minimize the amount of albumin-antibiotic binding in tear film.
细菌性角膜炎是一种常见且严重的病症，如果不及时、充分治疗，常常会导致视力受损甚至眼睛失明。局部血液制品常与局部抗生素同时使用，有助于减轻眼表释放的蛋白酶引起的角膜“溶解”。然而，血液制品富含白蛋白，可能因药物 - 蛋白质结合而影响抗生素的疗效。在本研究中，从10只健康犬和10匹健康马采集血清和血浆样本，获取新鲜和冷冻（-20°C保存1个月）的等分试样用于实验。使用物种特异性ELISA试剂盒对白蛋白水平进行定量。从患有感染性角膜炎的犬类患者中分离出30株细菌（10株、10株、10株），分别用空白平板以及商业药敏平板（Sensititre™ JOEYE2）进行检测以评估在不存在（对照）或存在八个测试组（犬或马的血清或血浆，新鲜或冷冻）的情况下17种不同抗生素的最低抑菌浓度（MIC）。犬类和马类血液制品中的白蛋白浓度分别为13.8 - 14.6mg/mL和25.9 - 26.5mg/mL。大多观察到马类血液制品（特别是血清，血浆影响较小）对分离菌有直接抗菌作用。虽然某些抗生素和眼部病原体的MIC也会降低（低至0.25倍），但在有血液制品存在时MIC通常会升高（高达10.8倍）。犬类血液制品[2（0.67 - 8.1）]的MIC中位数（范围）变化倍数比马类血液制品[2（0.5 - 5）]显著更大（P = 0.004）。在实际应用中，临床医生应考虑使用马类而非犬类血液制品（对抗菌药敏性影响较小），血清优于血浆（抗菌效果更佳），并在最后一次滴注抗生素眼药水后≥15分钟再给予血液制品，以尽量减少泪膜中白蛋白 - 抗生素结合的量。
