Occurrence and determinants of Klebsiella species bloodstream infection in the western interior of British Columbia, Canada

Klebsiella species are among the most common causes of bloodstream infection (BSI). However, few studies have evaluated their epidemiology in non-selected populations. The objective was to define the incidence of, risk factors for, and outcomes from Klebsiella species BSI among residents of the western interior of British Columbia, Canada. Population-based surveillance was conducted between April 1, 2010 and March 31, 2017. 151 episodes were identified for an incidence of 12.1 per 100,000 population per year; the incidences of K. pneumoniae and K. oxytoca were 9.1 and 2.9 per 100,000 per year, respectively. Overall 24 (16%) were hospital-onset, 90 (60%) were healthcare-associated, and 37 (25%) were community-associated. The median patient age was 71.4 (interquartile range, 58.8–80.9) years and 88 (58%) cases were males. Episodes were uncommon among patients aged < 40 years old and no cases were observed among those aged < 10 years. A number of co-morbid medical illnesses were identified as significant risks and included (incidence rate ratio; 95% confidence interval) cerebrovascular accident (5.9; 3.3–9.9), renal disease 4.3; 2.5–7.0), cancer (3.8; 2.6–5.5), congestive heart failure (3.5; 1.6–6.6), dementia (2.9; 1.5–5.2), diabetes mellitus (2.6; 1.7–3.9), and chronic obstructive pulmonary disease (2.3; 1.5–3.5). Of the 141 (93%) patients admitted to hospital, the median hospital length stay was 8 days (interquartile range, 4–17). The in-hospital and 30-day all cause case-fatality rates were 24/141 (17%) and 27/151 (18%), respectively. Klebsiella species BSI is associated with a significant burden of illness particularly among those with chronic co-morbid illnesses.