Kato Hideo, Hagihara Mao, Hiramatsu Shun-Ichi, Suematsu Hiroyuki, Nishiyama Naoya, Asai Nobuhiro, Mikamo Hiroshige, Yamamoto Kazuko, Iwamoto Takuya
Department of Pharmacy, Mie University Hospital, Mie, Japan.
Department of Clinical Pharmaceutics, Division of Clinical Medical Science, Mie University Graduate School of Medicine, Mie, Japan.
JAC Antimicrob Resist. 2024 Jun 4;6(3):dlae092. doi: 10.1093/jacamr/dlae092. eCollection 2024 Jun.
Ceftriaxone is administered in regimens of either 2 g once-daily or 1 g twice-daily for the treatment of pneumonia caused by . Previous clinical study suggests the 2 g once-daily regimen is more effective, but comparison of antimicrobial efficacy between are lacking.
To assess the antimicrobial efficacy of these two ceftriaxone regimens against using a murine model of pneumonia.
The study employed three isolates with ceftriaxone MICs of 1, 2 and 4 mg/L and two human-simulated regimens based on the blood concentration of ceftriaxone (1 g twice-daily and 2 g once-daily). Antimicrobial activity was quantified based on the change in bacterial counts (Δlog cfu/lungs) observed in treated mice after 24 h, relative to the control mice at 0 h.
The human-simulated 2 g once-daily regimen of ceftriaxone exhibited significantly higher antimicrobial activity against isolates with MICs of 1 and 2 mg/L compared with the 1 g twice-daily regimen (1 mg/L, -5.14 ± 0.19 Δlog cfu/lungs versus -3.47 ± 0.17 Δlog cfu/lungs, < 0.001; 2 mg/L, -3.41 ± 0.31 Δ log cfu/lungs versus -2.71 ± 0.37 Δlog cfu/lungs, = 0.027). No significant difference in antimicrobial activity was observed against the isolate with a MIC of 4 mg/L between the two regimens (-0.33 ± 0.18 Δlog cfu/lungs versus -0.42 ± 0.37 Δlog cfu/lungs, = 0.684).
2 g once-daily regimen of ceftriaxone is more effective for treating pneumonia caused by with MICs of ≤2 mg/L.
头孢曲松用于治疗由[病原体名称未给出]引起的肺炎时，给药方案为每日一次2g或每日两次1g。既往临床研究表明每日一次2g的方案更有效，但缺乏对[两种方案]抗菌效果的比较。
使用小鼠肺炎模型评估这两种头孢曲松方案对[病原体名称未给出]的抗菌效果。
该研究采用了三种头孢曲松最低抑菌浓度（MIC）分别为1、2和4mg/L的[病原体名称未给出]分离株，以及基于头孢曲松血药浓度的两种模拟人体给药方案（每日两次1g和每日一次2g）。抗菌活性通过比较给药24小时后治疗组小鼠肺内细菌计数的变化（Δlog cfu/肺）与0小时对照组小鼠来定量。
与每日两次1g的方案相比，模拟人体每日一次2g的头孢曲松方案对MIC为1和2mg/L的[病原体名称未给出]分离株表现出显著更高的抗菌活性（1mg/L时，-5.14±0.19Δlog cfu/肺对-3.47±0.17Δlog cfu/肺，P<0.001；2mg/L时，-3.41±0.31Δlog cfu/肺对-2.71±0.37Δlog cfu/肺，P = 0.027）。两种方案对MIC为4mg/L的[病原体名称未给出]分离株的抗菌活性无显著差异（-0.33±0.18Δlog cfu/肺对-0.42±0.37Δlog cfu/肺，P = 0.684）。
每日一次2g的头孢曲松方案治疗MIC≤2mg/L的[病原体名称未给出]所致肺炎更有效。
