2. A76-year-old man with atherosclerosis had been previously admitted for abdominal aneurysm and resection of the perirenal aorta. He had several follow-up admissions over the next year for postoperative wound infections, with accompanying bacteremia, alternating between Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecium, and Candida glabrata. On his final admission, blood cultures were positive, with numerous gram-positive cocci in pairs and chains in the smear, but subculture of the bottle showed no growth aerobically with increased CO2 on blood agar or chocolate agar or anaerobically on Brucella agar. QUESTIONS a) What is this organism and what would you do to grow it? b) To control infection, screening for vancomycin resistance in enterococci on selected hospitalized patients is important. What is a cost-effective screening method? c) Many genera of gram-positive cocci are catalase negative, but only a few are vancomycin-resistant. Name these genera, and indicate how they can be differentiated from vancomycin-resistant enterococci.
2. A76-year-old man with atherosclerosis had been previously admitted for abdominal aneurysm and resection of the perirenal aorta. He had several follow-up admissions over the next year for postoperative wound infections, with accompanying bacteremia, alternating between Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecium, and Candida glabrata. On his final admission, blood cultures were positive, with numerous gram-positive cocci in pairs and chains in the smear, but subculture of the bottle showed no growth aerobically with increased CO2 on blood agar or chocolate agar or anaerobically on Brucella agar. QUESTIONS a) What is this organism and what would you do to grow it? b) To control infection, screening for vancomycin resistance in enterococci on selected hospitalized patients is important. What is a cost-effective screening method? c) Many genera of gram-positive cocci are catalase negative, but only a few are vancomycin-resistant. Name these genera, and indicate how they can be differentiated from vancomycin-resistant enterococci.
