Concept explainers
Clinical Case Study Deadly Horizontal Gene Transfer
Sarah might have been 85 years old, but her mind was still sharp; it was her body that was failing. After she broke her hip by falling in the bathroom, she had succumbed to a series of complications that ultimately required admittance to a large university-associated hospital in New York City. Treatment necessitated a urinary catheter, a feeding tube, and intensive antibiotic therapy. While hospitalized, she acquired a life-threatening urinary tract infection with multi-drug-resistant (MDR) Enterococcus faecium.
Enterococci are normal members of the microbiota of the colon, yet these Gram-positive bacteria have a propensity to acquire genes that convey resistance to antimicrobial drugs. As a result of such horizontal gene transfer, E. faecium has become an MDR bacterium- that is, a strain resistant to many different kinds of antimicrobials. Drug-resistant enterococci are a leading cause of healthcare-associated infections (nosocomial infections).
Physicians treated Sarah with a series of antimicrobial drugs, including metronidazole, penicillin, erythromycin, ciprofloxacin, and vancomycin, but to no avail. After 90 days of hospitalization, she died.
- 1. Define healthcare-associated infection.
- 2. What is the likely source of Sarah’s infection?
- 3. List three ways by which E. faecium might have acquired genes for drug resistance.
- 4. How can hospital personnel prevent the spread of resistant E. faecium throughout the hospital?
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MICROBIOLOGY WITH DISEASE BY TAXONOMY
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