Clinical Analysis Of Bloodstream Infections Due To Pseudomonas Aeruginosa

Objective:This study explored the risk factors and outcomes of bloodstream infections due to Pseudomonas aeruginosa, to guide the early and specific treatment.Methods: A 1:1 matched case-control study was conducted in Fujian provincial hospital in 2015.Inclusion criteria: Patients(?18 years old) with confirmed clinical signs of PAE infection. And PAE was isolated from at least one set of blood cultures of samples collected from the patients. Only the first bacteremia episode in each patient was included in this study. Exclusion criteria: There were bloodstream infections due to other pathogens before PAE bacteremia. And PAE was isolated from a single blood culture, and in subsequent blood culture, bacteremia was cleared without any treatment.Patients with bloodstream infections due to PAE were compared with control patients with bloodstream infections due to Klebsiella pneumonia or Escherichia coli between January 2006 and September 2015. According to matching criteria based on underlying disease, age(±10 years), hospital ward and gender. We focused on matching case and control patients with the same underlying primary disease and the length of hospital stay before infection.Subsequently, control patients with similar age and the same hospital ward. If this criterion was not satisfied,control patients with a gender similar to that of case patients were prioritized. Finally univariate and multivariate logistic regression analyses were performed to explore the risk factors and outcomes of bloodstream infections due to PAE.Results: There were 83 cases of bloodstream infections due to PAE. A total of 56 case patients with PAE bacteremia were matched with 56 control patients with E.coli bacteremia or KP bacteremia. These patients were excluded which were included six children, two cases of outpatients, five cases of incompleted datas, sever cases of bloodstream infections due to other pathogens before PAE, six cases without suitable matching case. Hospital ward could not be matched in 3 patient pairs. Gender could bloodstream infections due to other pathogens before PAE, six cases without suitable not be matched in 10 patient pairs. All case and control patient pairs were matched with the same primary disease,age,gender,hospital ward and the length of hospital stay before infection(P>0.05). The study found that the primary site of infection was similar between the two groups(P> 0.05). The 30-day mortality rate for the case and concrol patients was 30.4% and 14.3%, respectively, and this difference was statistically significant(P= 0.041). Therefore, the attributable mortality was 16.1%.Conditional logistic regression analysis showed that the predisposing factors specific for the detection of PAE bacteremia were previous use of more than two types of Antipseudomonal antibiotics(OR:4.92;95%CI: 1.31~18.44;P:0.045) and anti-MRSA drugs(OR: 9.09; 95%CI: 1.05 ~ 78.9; P:0.018). The APACHE-II ratings(OR:1.23,95%CI:1.08 ~ 1.40,P:0.001) and inappropriate empiric antimicrobial treatment(OR: 6.55,95%CI: 1.44 ~ 29.72,P:0.01) was the independent risk factor for mortality in PAE bacteremia.Conclusions: Disease severity was a critical factor for mortality in our patients with PAE bacteremia.Overall,the rational use of antibiotics and more appropriate treatment might improve the prognosis of patients with bloodstream infections due to P.aeruginosa. clinicians should take a full history of hospitalization and medication,timely assess the condition to predict the likelihood of PAE bacteremia, and give appropriate empiric antimicrobial treatment to improve prognosis.