We are proud to announce that our ID fellow and current intern–Dr. Nader Tashtoush has been selected for a competitive travel grant to present his research at the Infectious Disease Society of America (IDSA)’s national meeting this fall! Please congratulate him if you see him.
Differentiating Patients with Multi-Drug Resistant (MDR) Gram-Negative Infections Present at the Time of Hospital Admission (POA) From Those with Susceptible (S) and Extremely-Drug Resistant (XDR) Pathogens
Nader Tashtoush, MD1; Jason M. Pogue, PharmD, Bakht Nishan, MD1, Dhafer Salem, MD1
Hamadullah Shaikh, MD1, Madiha Salim, MD1; Amina Pervaiz, MD;1 Aditya Kotecha1 Shigehiko Karino, MD1 Sorabh Dhar, MD1, Keith S. Kaye, MD, MPH1
Department of Medicine & Division of Infectious Diseases
Detroit Medical Center, Wayne State University, Detroit, Michigan
Treatment for MDR Gram-negative bacilli (GNB), defined as extended-spectrum- beta-lactamase-producing enterobacteriaceae (ESBLs) and beta-lactam resistant Pseudomonas aeruginosa, is limited to carbapenems and ceftolozane/tazobactam (CT). Acinetobacter baumannii and carbapenem-resistant enterobacteriaceae (XDR GNB), often require treatment with toxic antibiotics. Differentiating patients at risk for MDR GNB from those with more susceptible (S ) and those with XDR GNB would allow clinicians to optimize empiric therapy while limiting exposure to broad spectrum and toxic agents. The aims of this study were to identify unique, independent predictors for patients with MDR GNB presenting during the initial 72 hours of admission (POA); and to quantify outcomes independently associated with infections due to MDR GNB.
A case-case-control and a retrospective matched cohort study were conducted, including patients with POA bloodstream infection or pneumonia, from 1/1/2010 -12/31/2013. Patients with MDR GNB were matched to patients with S GNB. A third group of XDR GNB patients were also included. Independent risk factors for MDR GNB in both models (vs S and vs XDR GNB) were considered unique for POA MDR GNB. The impact of MDR GNB on clinical outcomes was determined in propensity-adjusted analyses.
The study population included 547 subjects: 190 MDR GNB; 190 S and 167 XDR GNB. Independent risk factors for MDR GNB, compared to both S and XDR GNB were identified (Table, see PDF). Mortality rates were 16%, 8% and 19% in the MDR, S and XDR GNB groups. MDR GNB was associated with increased mortality compared to the S (OR = 3.6, 95% CI =1.1-11.9) but was similar to the XDR GNB group.
Among patients with suspected invasive POA Gram-negative infection, age > 65 years, chronic lung disease and recent surgery, were unique independent risk factors for MDR GNB.