Risk Factors and Outcome of Klebsiella Pneumoniae Bacteraemia In Adult

Introduction Klebsiella pneumoniae bacteraemia is a major cause of morbidity and mortality in hospitals. Multidrug resistance associated with extended spectrum β lactamase and K. pneumoniae carbapenemase ( KPC ) organisms is a growing health threat. The purposes of this study is determine the demographic patterns, risk factors and outcome of K. pneumoniae bacteraemia in tertiary hospital in the Southern region of Malaysia.

Methods Single-center retrospective analysis involving all adults with K. pneumoniae bacteraemia in Sultan Ismail Hospital, Johor Bahru, Malaysia in 2016. Data on demographic patterns , risk factors , medical comorbidities , source of infection and in hospital mortality were obtained from the electronic medical records. 24,143 adult admissions with 5714 blood culture samples collected , of which 1124 ( 19.7 % ) were positive cultures. 825 blood culture samples met eligibility criterias.  299 samples were excluded as they were deemed clinically insignificant or contaminant •Analysis of data performed using SPSS version 18. A p-value of <0.05 was considered statistically significant.

Results Gram negative bacteraemia accounted for 69.2 % of total positive blood cultures . Klebsiella pneumoniae was the commonest blood-stream pathogen (185 cases, 22.4 %) followed by Escherichia coli (179 cases , 21.7 %) and Staphylococcus aureus (153 cases, 18.4 %), Streptococcus spp (75 cases, 9.1 %) and Acinetobacter spp (42 cases, 5.1 %) Mean age was 54.9 ( SD 15.4 ) with an overall in-hospital mortality rate of 46.5 %. Extended Spectrum Beta Lactamase (ESBL) producing and Carbapenem resistant K. pneumoniae accounted for 37.3% (n= 69) and 1.1 % (n= 2) cases respectively (Table 1) The common sources of K. pneumoniae bacteraemia were primary bloodstream infections (40.5 % , n=75) , followed by pneumonia (23.8%, n= 44) and urinary tract infection (15.1%, n=28), liver abscess ( 6.5%, n=12) and skin and soft tissue infection ( 4.3 %, n=8) (Chart 1). Older age ( p=0.005 ) and chronic liver disease (p= 0.008) were predictors of in-hospital mortality (Table 3).

Discussion Gram negative bacteraemia accounted for 69.2 % of total positive blood cultures , compared to a study conducted in a teaching hospital in Kuala Lumpur 2 decades ago which reported higher Gram positive bacteraemia (56.7 % of the blood cultures) (1). K.pneumoniae has surpassed Escherichia coli to become the predominant gram negative pathogen in our institution ( 22.4 % versus 21.7 %). Multidrug resistance associated with extended spectrum β lactamase (37.3 %) and K. pneumoniae carbapenemase (1.1%) organisms is a growing health threat. Diabetes mellitus , cancer and alcohol use disorders were risk factors associated with K. pneumoniae bacteraemia similar to previous reported study. Overall in-hospital mortality rate of 46.5% , similar to other reported study. Older age and chronic liver disease were associated with higher mortality rate.

Conclusion Diabetes mellitus , cancer and alcohol use disorders were independent risk factors associated with Klebsiella pneumoniae bacteraemia. Higher mortality rate was observed in elderly and patients with chronic liver disease.