Factors associated with epidemic multiresistant Pseudomonas aeruginosa infections in a hospital with AIDS-predominant admissions

INTRODUCTION: Infections caused by multiresistant Pseudomonas aeruginosa (MR-PA) have been associated with persistent infections and high mortality in acquired immunodeficiency syndrome (AIDS) patients. Therefore, understanding the predisposing factors for infection/colonization by this agent is critical for controlling outbreaks caused by MR-PA in settings with AIDS patients. OBJECTIVEAND METHODS: To analyze the presence of factors associated with the acquisition of an epidemic MR-PA strain in a hospital with AIDS-predominant admission. A case-control study was carried out in which cases and controls were gathered from a prospective cohort of all hospitalized patients in an infectious disease hospital during a five-year study period. RESULTS: Multivariate logistic regression analysis demonstrated that enteral nutrition OR = 14.9), parenteral nutrition (OR = 10.7), and use of ciprofloxacin (OR = 8.9) were associated with a significant and independent risk for MR-PA acquisition. CONCLUSIONS: Although cross-colonization was likely responsible for the outbreaks, the use of ciprofloxacin was also an important factor associated with the acquisition of an epidemic MR-PA strain. More studies are necessary to determine whether different types of nutrition could lead to modification of gastrointestinal flora, thereby increasing the risk for infection/colonization by MR-PA in this population.

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

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 percent) were immunocompromised with AIDS (n = 10) or HTLV-1 infections (n = 5). Of the followed patients, 67 percent had persistent and/or recurrent infections, and 92 percent 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.