Outbreaks, persistence, and high mortality rates of multiresistant Pseudomonas aeruginosa infections in a hospital with AIDS-predominant admissions

Abstract

Introduction: Authors have reported increased incidence of multiresistant Pseudomonas aeruginosa (MR-PA) infections worldwide over the last decade. Researchers have proposed multifaceted approaches to control MR-PA infections, but none have been reported in the acquired immunodeficiency syndrome (AIDS) setting. Objective and Methods: Herein we report the impact of a multifaceted intervention for controlling MR-PA over five years in a hospital with AIDS-predominant admissions and describe the clinical characteristics of MR-PA infection in our patient population. The clinical outcomes of infected patients and molecular characteristics of the isolated strains were used as tools for controlling MR-PA infection rates. Results: Significant temporary decrease of new infections was achieved after intervention, although a high level of diagnostic suspicion of nosocomial infection was maintained. We obtained 35 P. aeruginosa isolates with multiresistant profiles from 13 infected and 3 colonized patients and 2 environmental samples. Most of the patients (94%) were immunocompromised with AIDS (n = 10) or HTLV-1 infections (n = 5). Of the followed patients, 67% had persistent and/or recurrent infections, and 92% died. We observed differences in the antibiotic-resistance pattern of MR-PA infection/colonization during two outbreaks, although the genetic profiles of the tested strains were identical. Conclusions: Therefore, we concluded that early multidisciplinary interventions are essential for reducing the burden caused by this microorganism in patients with AIDS. Prolonged or suppressive antibiotic-based therapy should be considered for MR-PA infections in patients with AIDS because of the persistence characteristic of MR-PA in these patients. Keywords: Pseudomonas aeruginosa, disease outbreaks, infection control, molecular epidemiology, acquired immunodeficiency syndrome