Infections by carbapenem-resistant Klebsiella pneumoniae (CRKp) are an increasing global threat with limited therapeutic options. Our objective was to evaluate clinical and microbiological outcomes of patients treated with amikacin for CRKp infections. We did a retrospective cohort of patients > 18 years old, with CRKp infections treated with amikacin in two tertiary care hospitals in Porto Alegre, Brazil. The impact of clinical factors, antibiotic treatment, and amikacin minimum inhibitory concentration (MIC) on patients’ 30-day mortality was assessed. Microbiological clearance and nephrotoxicity (assessed by RIFLE score) were evaluated as secondary outcomes. A Cox regression analysis was done for mortality. We included 84 patients for analysis. Twenty-nine (34.5%) patients died in 30 days. Amikacin MIC values ranged from 0.125 to 8 μg/mL and did not influence on mortality, regardless of the prescribed dose of this antibiotic (P = 0.24). Bacterial clearance occurred in 17 (58.6%) of 29 patients who collected subsequent cultures. Two (16.6%) of the 12 persistently positive cultures changed the amikacin susceptibility profile from susceptible to intermediate. Twenty-nine (37.2%) patients developed acute kidney injury (AKI): risk 13, injury 11, and failure 5. Risk factors for AKI were higher baseline eGFR (P < 0.01) and combination therapy with colistin (P = 0.02). Comparing patients who received combination with colistin vs polymyxin B, AKI occurred in 60.0% vs 20.6%, respectively, P < 0.01. Fifteen of the 16 (16.6%) patients who developed renal injury or failure were receiving colistin. In conclusion, amikacin was an effective treatment for CRKp infections. Within susceptible range, amikacin MIC values did not influence on clinical outcomes. Combination therapy of amikacin and colistin was highly nephrotoxic and should be used with caution.

耐碳青霉烯类肺炎克雷伯菌(CR Kp ) 感染是一种日益严重的全球威胁，治疗选择有限。我们的目标是评估接受阿米卡星治疗的 CR Kp感染患者的临床和微生物学结果。我们对年龄 > 18 岁、CR Kp的患者进行了回顾性队列研究在巴西阿雷格里港的两家三级医院接受阿米卡星治疗的感染。评估了临床因素、抗生素治疗和阿米卡星最低抑菌浓度 (MIC) 对患者 30 天死亡率的影响。微生物清除率和肾毒性（通过 RIFLE 评分评估）被评估为次要结果。对死亡率进行了 Cox 回归分析。我们纳入了 84 名患者进行分析。29 名 (34.5%) 患者在 30 天内死亡。阿米卡星的 MIC 值范围为 0.125 至 8 μg/mL，无论处方剂量如何，阿米卡星都不会影响死亡率（P = 0.24)。收集后续培养物的 29 名患者中有 17 名 (58.6%) 发生了细菌清除。12 种持续阳性培养物中的两种（16.6%）将阿米卡星的敏感性曲线从敏感变为中等。29 名 (37.2%) 患者发生急性肾损伤 (AKI)：风险 13、损伤 11 和失败 5。AKI 的危险因素是较高的基线 eGFR ( P  < 0.01) 和与粘菌素联合治疗 ( P  = 0.02)。比较接受多粘菌素与多粘菌素 B 联合治疗的患者，AKI 发生率分别为 60.0% 和 20.6%，P  < 0.01。16 名（16.6%）出现肾损伤或衰竭的患者中有 15 名（16.6%）正在接受粘菌素治疗。总之，阿米卡星是治疗 CR Kp的有效方法感染。在敏感范围内，阿米卡星 MIC 值不影响临床结果。阿米卡星和多粘菌素的联合治疗具有高度肾毒性，应谨慎使用。