Genetic analysis of multiple vancomycin-resistant Enterococcus isolates obtained serially from two long-term-care patients.

Fifty-eight vancomycin-resistant enterococcal isolates were obtained from two patients over 9 weeks. Numerous pulsed-field gel electrophoresis fingerprinting types were isolated from each patient. By PCR, all isolates were vanA+. However, many isolates from patient B were found to lack vanA by hybridization. Our results demonstrate the importance of examining multiple isolates, especially from patients who are at high risk of infection.