Department of Critical Care Medicine, Second Affiliated Hospital, Zhejiang University School of Medicine, 88 Jiefang Road, Hangzhou, 310009, China.
Department of Intensive Care Unit, Ningbo Fourth Hospital, 291 Donggu Road, Dandong Street, Ningbo, 315700, Zhejiang, China.
BMC Pulm Med. 2023 Mar 28;23(1):102. doi: 10.1186/s12890-023-02394-8.
The clinical characteristics of Klebsiella pneumoniae (KP) pneumonia and KP bloodstream infection (KP-BSI) are often reported, while the risk factors for KP pneumonia developing into secondary KP-BSI (KP-pneumonia/KP-BSI) are largely unknown. Therefore, this study attempted to investigate the clinical characteristics, risk factors and outcomes of KP-pneumonia/KP-BSI.
A retrospective observational study was conducted at a tertiary hospital between January 1, 2018, and December 31, 2020. The patients were divided into groups of KP pneumonia alone and KP pneumonia/KP-BSI, and the clinical information were collected from medical records electronic system.
A total of 409 patients were finally recruited. According to the multivariate logistic regression analysis, male sex (adjusted odds ratio [aOR] 3.7; 95% CI, 1.44-9.5), immunosuppression (aOR, 13.52; 95% CI, 2.53,72.22), APACHE II score higher than 21 (aOR, 3.39; 95% CI, 1.41-8.12), serum procalcitonin (PCT) levels above 1.8 ng/ml (aOR, 6.37; 95% CI, 2.67-15.27), ICU stay of more than 2.5 days before pneumonia onset (aOR, 1.09; 95% CI, 1.02,1.17), mechanical ventilation (aOR, 4.96; 95% CI, 1.2,20.5), Klebsiella pneumoniae isolates producing extended spectrum β-lactamase (ESBL-positive KP) (aOR, 12.93; 95% CI, 5.26-31.76), and inappropriate antibacterial therapy (aOR, 12.38; 95% CI, 5.36-28.58) were independent factors of KP pneumonia/KP BSI. In comparison with the patients with KP pneumonia alone, the patients with KP pneumonia/KP BSI showed an almost 3 times higher incidence of septic shock (64.4% vs. 20.1%, p < 0.01), a longer duration of mechanical ventilation, and longer lengths of ICU stay and total hospital stay (median days, 15 vs. 4,19 vs. 6, 34 vs. 17, respectively, both p < 0.01). Additionally, the overall in-hospital crude mortality rate in the patients with KP-pneumonia/KP-BSI was more than two times higher than that in those with KP pneumonia alone (61.5% vs. 27.4%, p < 0.01).
Factors including male sex, immunosuppression, APACHE II score higher than 21, serum PCT levels above 1.8 ng/ml, ICU stay of more than 2.5 days before pneumonia onset, mechanical ventilation, ESBL-positive KP, and inappropriate antibacterial therapy are independent risk factors for KP pneumonia/KP-BSI. Of note, the outcomes in patients with KP pneumonia worsen once they develop secondary KP-BSI, which merits more attention.
肺炎克雷伯菌（KP）肺炎和血流感染（KP-BSI）的临床特征常被报道，而 KP 肺炎发展为继发性 KP-BSI（KP-肺炎/KP-BSI）的危险因素在很大程度上尚不清楚。因此，本研究试图探讨 KP-肺炎/KP-BSI 的临床特征、危险因素和结局。
本研究为 2018 年 1 月 1 日至 2020 年 12 月 31 日在一家三级医院进行的回顾性观察性研究。将患者分为单纯 KP 肺炎组和 KP-肺炎/KP-BSI 组，并从病历电子系统中收集临床信息。
最终共纳入 409 例患者。多因素 logistic 回归分析显示，男性（调整优势比[aOR]3.7；95%CI，1.44-9.5）、免疫抑制（aOR，13.52；95%CI，2.53，72.22）、APACHE II 评分高于 21（aOR，3.39；95%CI，1.41-8.12）、血清降钙素原（PCT）水平高于 1.8ng/ml（aOR，6.37；95%CI，2.67-15.27）、肺炎发病前 ICU 入住时间超过 2.5 天（aOR，1.09；95%CI，1.02，1.17）、机械通气（aOR，4.96；95%CI，1.2，20.5）、产超广谱β-内酰胺酶（ESBL）肺炎克雷伯菌（aOR，12.93；95%CI，5.26-31.76）和抗菌治疗不当（aOR，12.38；95%CI，5.36-28.58）是 KP-肺炎/KP-BSI 的独立危险因素。与单纯 KP 肺炎组相比，KP-肺炎/KP-BSI 组患者发生感染性休克的几率几乎高出 3 倍（64.4%比 20.1%，p<0.01），机械通气时间延长，ICU 入住时间和总住院时间延长（中位数天数，15 比 4，19 比 6，34 比 17，均 p<0.01）。此外，KP-肺炎/KP-BSI 组患者的院内总死亡率是单纯 KP 肺炎组的两倍多（61.5%比 27.4%，p<0.01）。
包括男性、免疫抑制、APACHE II 评分高于 21、血清 PCT 水平高于 1.8ng/ml、肺炎发病前 ICU 入住时间超过 2.5 天、机械通气、产 ESBL 肺炎克雷伯菌和抗菌治疗不当是 KP-肺炎/KP-BSI 的独立危险因素。值得注意的是，KP 肺炎患者一旦发生继发性 KP-BSI，病情会恶化，这值得更多关注。
