Ufuk Sonmez, Derya Caglayan, Sarp Singil, Gursel Ersan, Sabri Atalay


Objective: Hospital-acquired pneumonia (HAP) developing in intensive care units (ICU) is an important problem. Gram-negative bacteria are the most important cause of HAP. Among these bacteria, Klebsiella pneumoniae is among the most important pathogens. The mortality rate for infections caused by carbapenem-resistant Klebsiella pneumoniae is high. Identifying mortality risk factors is crucial to prevent potential deaths. The aim of this study was to determine the risk factors associated with mortality in HAP due to Klebsiella pneumoniae in intensive care unit patients.

Material and Methods: This cross-sectional study was conducted between 01. May 2021. and 01. May 2023. in the Anesthesia and Reanimation Intensive Care Unit of Izmir Tepecik Training and Research Hospital. Patients aged 18 years who were diagnosed with hospital-acquired pneumonia due to Klebsiella pneumoniae were included in the study. The dependent variable of the study was 14-day mortality due to Klebsiella pneumoniae pneumonia. Independent variables were presence of COVID-19, bacteremia, ceftazidime/avibactam treatment, intubation, sepsis, Charlson comorbidity score, and laboratory parameters. We conducted logistic regression analysis using the backward elimination method to identify independent predictors of mortality.

Results: A total of 176 patients were included in the study. The mean age of the patients was 64.6±16.2 years and 64.2% were male. The 14-day mortality rate was 29% (n:51). In the regression analysis performed to determine the risk factors for mortality; in the univariate regression analysis, day 0 leukocyte count > 10.600/mm3 (OR: 2.31; 95% CI: 1.10-4.84), platelet value < 140. 000/mm3 (OR: 2.26; 95% CI: 1.06-4.81), AST >50 U/L (OR: 2.40; 95% CI: 1.20-4.79) and creatinine >1.3 mg/dL (OR: 1.96; 95% CI: 1.006-3.82) were associated with mortality. In multivariate regression analysis, a leukocyte count >10.600/mm3 (OR: 2.30; 95% CI: 1.03-5.14) and an AST >50 U/L (OR: 2.23; 95% CI: 1.04-4.75) were found to be independent predictors of mortality.

Conclusion: In conclusion, leukocytosis and high AST levels were found to be independent risk factors associated with mortality in cases of Klebsiella pneumoniae in the intensive care unit. Taking these factors into account, in addition to other parameters and scores that determine the prognosis of patients, may be useful in reducing mortality.


Klebsiella pneumoniae, mortality, pneumonia, risk factors, intensive care units

Full Text:



Li L, Huang L, Liu X, Ye Y, Sai F, Huang H. Intensive care unit-acquired pneumonia caused by Klebsiella pneumoniae in China: Risk factors and prediction model of mortality. Medicine (Baltimore). 2023;102(12):e33269. doi: 10.1097/md.0000000000033269.

Weiner-Lastinger LM, Abner S, Edwards JR, Kallen AJ, Karlsson M, Magill SS, et al. Antimicrobial-resistant pathogens associated with healthcare-associated infections: Summary of data reported Healthcare Safety Network, 2015-2017. Infect Control Hosp Epidemiol. 2020;41(1):1-18. doi: 10.1017/ice.2019.296.

Shirley M. Ceftazidime-Avibactam: a review in the treatment of serious gram-negative bacterial infections. Drugs. 2018;78(6):675-92. doi: 10.1007/s40265-018-0902-x.

Falagas ME, Tansarli GS, Karageorgopoulos DE, Vardakas KZ. Deaths attributable to carbapenem-resistant Enterobacteriaceae infections. Emerg Infect Dis. 2014;20(7):1170-5. doi: 10.3201/eid2007.121004.

Xu L, Sun X, Ma X. Systematic review and meta-analysis of mortality of patients infected with carbapenem-resistant Klebsiella pneumonia. Ann Clin Microbiol Antimicrob. 2017;16(1):18. doi: 10.1186/s12941-017-0191-3.

Tumbarello M, Raffaelli F, Giannella M, Mantengoli E, Mularoni A, Venditti M, et al. Ceftazidime-Avibactam use for Klebsiella pneumoniae Carbapenemase-Producing K. pneumoniae infections: a retrospective observational multicenter study. Clin Infect Dis. 2021;73(9):1664-76. soi: 10.1093/cid/ciab176.

SOSYAL GÜVENLİK KURUMU SAĞLIK UYGULAMA TEBLİĞİNDE DEĞİŞİKLİK YAPILMASINA DAİR TEBLİĞ. 28 April 2021. https://www.resmigazete.gov.tr/eskiler/2021/04/20210428M1-1.htm. Access date: 16.08.2023.

Vo-Pham-Minh T, Duong-Thi-Thanh V, Nguyen T, Phan-Tran-Xuan Q, Phan-Thi H, Bui-Anh T, et al. The impact of risk factors on treatment outcomes of nosocomial pneumonia due to gram-negative bacteria in the Intensive care unit. Pulm Ther. 2021;7(2):563-74. doi: 10.1007/s41030-021-00175-4.

Wenwen S, Xiquan L, Aiqin L. Risk factors of carbapenem-resistant gram-negative bacteria pneumonia and mortality. Cell Mol Biol (Noisy-le-grand). 2022;68(10):124-9.Doi: 10.14715/cmb/2022.68.10.20.

Kalil AC, Metersky ML, Klompas M, Muscedere J, Sweeney DA, Palmer LB, et al. Management of adults with hospital-acquired and ventilator-associated pneumonia: 2016 clinical practice guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis. 2016;63(5):e61-e111. doi: 10.1093/cid/ciw353.

Chen IR, Lin SN, Wu XN, Chou SH, Wang FD, Lin YT. Clinical and microbiological characteristics of bacteremic pneumonia caused by Klebsiella pneumoniae. Front Cell Infect Microbiol. 2022;12:903682. doi: 10.3389/fcimb.2022.903682.

Jiao J, Li Z, Wu X, Cao J, Liu G, Liu Y, et al. Risk factors for 3-month mortality in bedridden patients with hospital-acquired pneumonia: A multicentre prospective study. PloS One. 2021;16(3):e0249198. doi: 10.1371/journal.pone.0249198.

Forstner C, Patchev V, Rohde G, Rupp J, Witzenrath M, Welte T, et al. Rate and predictors of bacteremia in afebrile community-acquired pneumonia. Chest. 2020;157(3):529-39. doi: 10.1016/j.chest.2019.10.006.

Ito R, Shindo Y, Kobayashi D, Ando M, Jin W, Wachino J, et al. Molecular epidemiological characteristics of Klebsiella pneumoniae associated with bacteremia among patients with pneumonia. J Clin Microbiol. 2015; 53(3): 879-86. doi: 10.1128/JCM.03067-14.

Rivera-Espinar F, Machuca I, Tejero R, Rodríguez J, Mula A, Marfil E, et al. Impact of KPC production and high-level meropenem resistance on all-cause mortality of ventilator-associated pneumonia in association with Klebsiella pneumoniae. Antimicrob Agents Chemother. 2020;64(6). doi: 10.1128/AAC.02164-19.

Tsolaki V, Mantzarlis K, Mpakalis A, Malli E, Tsimpoukas F, Tsirogianni A, et al. Ceftazidime-Avibactam to treat life-threatening infections by carbapenem-resistant pathogens in critically ill mechanically ventilated patients. Antimicrob Agents Chemother. 2020;64(3):e02320-19. doi: 10.1128/AAC.02320-19.

Garcia-Vidal C, Sanjuan G, Moreno-García E, Puerta-Alcalde P, Garcia-Pouton N, Chumbita M, et al. Incidence of co-infections and superinfections in hospitalized patients with COVID-19: a retrospective cohort study. Clin Microbiol Infect. 2021;27(1):83-8. doi: 10.1016/j.cmi.2020.07.041.

Musuuza JS, Watson L, Parmasad V, Putman-Buehler N, Christensen L, Safdar N. Prevalence and outcomes of co-infection and superinfection with SARS-CoV-2 and other pathogens: a systematic review and meta-analysis. PloS One. 2021;16(5):e0251170. doi: 10.1371/journal.pone.0251170.

Vicco MH, Ferini F, Rodeles L, Scholtus P, Long AK, Musacchio HM. In-hospital mortality risk factors in community-acquired pneumonia: evaluation of immunocompetent adult patients without comorbidities. Rev Assoc Med Bras (1992). 2015;61(2):144-9. doi: 10.1590/1806-9282.61.02.144.

Sonmez U, Atalay S, Abakay H, Çağlayan D, Arı A, Özkarakaş H, et al. Factors affecting clinical course and mortality among COVID-19 patients receiving convalescent plasma treatment. Tropical Health and Medical Research. 2023;5(1):1-13. doi:10.35916/thmr.v4i1.74.

ValenÄić L, TokmadžićSotoÅ¡ek V, Kuharić J, Å ustić A. The incidence of nosocomial infections in patients with isolated severe traumatic brain injury. Sanamed. 2015;10(3):185-92. doi: 10.5937/sanamed1503185V.


  • There are currently no refbacks.

Copyright (c) 2023 Ufuk Sonmez

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.