Increasing Incidence of MDROs: An Emerging Global Concern


Increasing Incidence of MDROs: An Emerging Global Concern



Infectious Diseases

Training Level



Henry Ford Hospital


Introduction: With massive efflux of civilians from violence-stricken countries, the high rates of colonization with multidrug-resistant organisms (MDROs) amongst the refugees is an emerging global concern. Our report describes two Middle Eastern patients who suffered severe traumatic injuries in their home countries, subsequently developing chronic wounds. Upon arrival to the United States, the patients sought treatment in our institution for wound infection with MDRO. Materials and methods: Clinical data was collected from the patients’ charts. Identification and susceptibility testing were performed as part of routine identification/susceptibility test in the clinical microbiology laboratory. MICs performed by manual microbroth dilution according to Clinical and Laboratory Standards Institute (CLSI) guidelines.Time kill curves used to determine in vitro synergy of Pseudomonas aeruginosa isolate in various antibiotic combinations (½ x MIC meropenem plus ½ x MIC colistin, ½ x MIC meropenum plus ½ x MIC colistin plus ½ x MIC rifampin and ½ x MIC meropenem plus ½ x MIC ceftazidime/avibactam). Mueller Hinton II broth was used. Samples were serially diluted at 0, 4 and 24 hours and plated on TSA II agar. Time kill curves were constructed, plotting colony counts over time, with synergy being defined as ≥2-log10 decrease in CFU/ml between the combination and its most active constituent after 24h, the number of surviving organisms in the presence of combination must be ≥2 log10 CFU/ml below the starting inoculum. Results: Patient 1 came from Syria, and patient 2 from Yemen. Both patients’ wound infections were healthcare-associated, with underlying chronic osteomyelitis. Both had multiple risk factors for MDRO, including multiple prior surgeries and antibiotic courses. Patient 1 culture grew CRE Klebsiella and MDR Morganella, and later ESBL Escherichia coli. Patient 2 culture grew Pseudomonas aeruginosa sensitive only to colistin. Patient 1 was treated with ertapenem. Patient 2 received rifampin+meropenen+colistin, the only antibiotic combination demonstrating synergistic killing. Both patients required prolonged therapy, and on follow up were doing well. Conclusions: Colonization with MDRO amongst Middle Eastern immigrants is an alarming phenomenon.In vitro experiments with available antibacterial agents may assist in the choice of therapy for MDRO strains when conventional options are exhausted.

Publication Date


Increasing Incidence of MDROs: An Emerging Global Concern