Pseudomonas aeruginosa bacteraemia: A five-year analysis of epidemiology, clinical profiles, and outcome in a Malaysian district hospital

INTRODUCTION: Pseudomonas aeruginosa is known to be the epitome of nosocomial infections associated with high morbidity and mortality. The dearth of local pseudomonal studies has prompted us to conduct this study with the following objectives: (1) to examine the local pseudomonal bacteraemia (PB) epidemiology and clinical characteristics, (2) to compare the 30-day mortality among PB of different onsets and (3) to determine the predictors of 30-day mortality outcome.

METHODS: This retrospective study was conducted in Hospital Seri Manjung, Perak, Malaysia. All cases of blood culture proven PB that occurred between 1st January 2015 and 31st December 2019 were reviewed. Subjects below 12 year old and whose index blood cultures grew more than one organism were excluded. Demographic, clinical and treatment data were collected using pre-tested data collection forms and analysed using SPSS version 20.0.

RESULTS: Among the 59 subjects included, healthcare associated (HCA) infections were the most prevalent, next to hospital onset (HO) and community onset (CO) infections. The commonest underlying comorbidities were cardiovascular disease, diabetes mellitus, and chronic kidney disease. Respiratory tract was the most frequently implicated source amongst all, while the urinary tract was more frequently implicated as the source of infection among HCA cases. Seventeen patients were admitted to ICU, and they were predominantly from the HO group. Despite having a higher rate of adequate empirical antibiotics administered, the HO group reported the lowest 30-day survival rate. Multiple logistic regression analysis demonstrated the following were independent predictors of 30-day mortality: requiring mechanical ventilator support, requiring central venous line insertion, not requiring surgery, and receiving inappropriate definite antibiotics.

CONCLUSION: The incidence of community onset PB was appreciably low, as cases were predominantly HCA and HO in origin. Significant morbidities were observed among pseudomonal infections, with HO infections portending the worst prognosis. Lastly, prognostic factors for determining the mortality caused by PB depended more on the severity of sepsis than the timeliness of appropriate antibiotics.