Serotypes and clonal types of penicillin-susceptible Streptococcus pneumoniae Navegación de entradas Sensitive EDTA-Based Microbiological Assays for Detection of Metallo--Lactamases in Nonfermentative Gram-Negative Bacteria Prevalence Studies of Vancomycin-Resistant Enterococci (VRE) for Monitoring a Passive Surveillance Program in a Pediatric Hospital.