Marsland Paula, Jain Rupali, Tverdek Frank, Hendrie Paul, Liu Catherine, Pergam Steven A, Bourassa Lori
Department of Medicine, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195-6420, USA.
Department of Pharmacy, University of Washington, 1959 NE Pacific St. HSB H-375, Seattle, WA 98195-7630, USA.
JAC Antimicrob Resist. 2024 Aug 5;6(4):dlae126. doi: 10.1093/jacamr/dlae126. eCollection 2024 Aug.
Viridans streptococci (VS) are opportunistic oral commensals and a common cause of bacteraemia in neutropenic patients. In this retrospective single centre cohort study, we investigated the prevalence of ceftriaxone resistance in VS (CRO-R VS) blood isolates between January 2005 and December 2022 from patients treated at a tertiary care hospital.
Blood culture isolates were identified using biochemicals and mass spectrometry. Susceptibility testing was performed by Kirby-Bauer and Epsilometer tests. Demographic data, clinical outcomes and antimicrobial use were assessed through electronic medical record review.
Among 791 patients with VS bacteraemia, 31 (4%) had confirmed CRO-R VS bacteraemia over the 18-year period; 20/31 (65%) were patients also treated at the Fred Hutchinson Cancer Center and were the focus of this study. Of these 20 patients, 18 (90%) had a known haematologic malignancy; 14 (70%) had undergone haematopoietic cell transplant (HCT); 18 (90%) were neutropenic at the time of culture. Two (10%) patients died within 30 days of CRO-R VS bacteraemia. All the CRO-R isolates (20/20) were members of the group, 12 were multi-drug resistant; all were susceptible to vancomycin. Most patients received vancomycin once blood cultures were positive for a Gram-positive organism.
During the study period, the frequency of VS isolate susceptibility testing increased; however, there was no concomitant increase in the percentage of CRO-R isolates at our facility. These data are important in an era where cefepime monotherapy is often used and reinforces the importance of routine resistance testing among VS bacteraemia.
草绿色链球菌（VS）是机会性口腔共生菌，也是中性粒细胞减少患者菌血症的常见病因。在这项回顾性单中心队列研究中，我们调查了2005年1月至2022年12月期间在一家三级护理医院接受治疗的患者的VS血培养分离株中头孢曲松耐药（CRO-R VS）的流行情况。
使用生化方法和质谱法对血培养分离株进行鉴定。采用 Kirby-Bauer 试验和 E 试验进行药敏试验。通过电子病历回顾评估人口统计学数据、临床结局和抗菌药物使用情况。
在791例VS菌血症患者中，在18年期间有31例（4%）确诊为CRO-R VS菌血症；20/31例（65%）患者也在弗雷德·哈钦森癌症中心接受治疗，是本研究的重点。在这20例患者中，18例（90%）患有已知的血液系统恶性肿瘤；14例（70%）接受过造血细胞移植（HCT）；18例（90%）在培养时中性粒细胞减少。2例（10%）患者在CRO-R VS菌血症发生后30天内死亡。所有CRO-R分离株（20/20）均为该组成员，12株为多重耐药；所有菌株对万古霉素敏感。一旦血培养革兰氏阳性菌呈阳性，大多数患者接受了万古霉素治疗。
在研究期间，VS分离株药敏试验的频率有所增加；然而，我们机构中CRO-R分离株的百分比并未随之增加。在经常使用头孢吡肟单药治疗的时代，这些数据很重要，并强化了VS菌血症患者常规耐药性检测的重要性。
