Effect of Duplicate Isolates of Methicillin-Susceptible and Methicillin-Resistant Staphylococcus aureus on Antibiogram Data

This is the published version, also available here: http://www.dx.doi.org/10.1128/JCM.41.10.4611-4616.2003

Nationwide antibiogram analysis using NCCLS M39-A guidelines

This is the published version, also available here: http://dx.doi.org/10.1128/JCM.43.6.2629-2634.2005.Lack of standardization in antibiogram (ABGM) preparation (the overall profile of antimicrobial susceptibility results of a microbial species to a battery of antimicrobial agents) has not been addressed until recently. The objective of this study was to analyze current antibiograms using the recently published NCCLS M39-A guidelines for preparation of antibiograms to identify areas for improvement in the reporting of antibiogram susceptibility data. Antibiograms from across the United States were obtained by various methods, including direct mailings, Internet searches, and professional contacts. Each ABGM collected was analyzed using prospectively defined elements from the M39-A guidelines. Additionally, seven quality indicators were also evaluated to look for the reporting of any atypical or inappropriate susceptibility data. The 209 antibiograms collected from 149 institutions showed at least 85% compliance to 5 of the 10 M39-A elements analyzed. Clinically relevant elements not met included annual analysis, duplicate isolate notation, and the exclusion of organisms with fewer than 10 isolates. As for the quality indicators evaluated, unexpected results included the 7% of antibiograms that reported 0% ampicillin susceptibility for Klebsiella pneumoniae. These findings suggest that antibiograms should be reviewed thoroughly by infectious disease specialists (physicians and pharmacists), clinical microbiologists, and infection control personnel for identification of abnormal findings prior to distribution

Effect of Duplicate Isolates of Methicillin-Susceptible and Methicillin-Resistant Staphylococcus aureus on Antibiogram Data

Duplicate Staphylococcus aureus isolates were analyzed to determine the impact of multiple isolates from the same patient on annual antibiogram data. During a 6-year period (1996 to 2001), 3,227 patients with 4,844 S. aureus isolates were evaluated. A total of 39% of patients with methicillin-resistant S. aureus (MRSA) (n = 860) and 23% of patients with methicillin-susceptible S. aureus (MSSA) (n = 2,367) infections had duplicate isolates. Cumulative data show that 91% of the patients during this 6-year period with duplicate isolates (2 to 13 duplicates/year) did not switch between MSSA and MRSA but retained the original S. aureus strain whether it was MSSA or MRSA. Rates of MRSA were calculated for each year by using all isolates and then eliminating duplicates. The impact of duplicate MRSA and MSSA isolates was evaluated by using the ratio of isolates per patient such that ratios of >1.0 indicate >1 isolate per patient. The 6-year ratio for MRSA was 1.90 isolates/patient, and the ratio for MSSA was 1.35. A significant difference (P < 0.05) was noted in the MRSA rates in 4 of 6 years when duplicate isolates were removed. Common phenotypic antibiogram patterns were compared for all MRSA isolates during the 6-year period, and 64% were of a single antibiogram phenotype. Eighty-eight percent of patients with duplicate MRSA isolates had phenotypically identical multiple isolates. The rate of MRSA differs when duplicate isolates are removed from the antibiogram data

Nationwide Antibiogram Analysis Using NCCLS M39-A Guidelines

Lack of standardization in antibiogram (ABGM) preparation (the overall profile of antimicrobial susceptibility results of a microbial species to a battery of antimicrobial agents) has not been addressed until recently. The objective of this study was to analyze current antibiograms using the recently published NCCLS M39-A guidelines for preparation of antibiograms to identify areas for improvement in the reporting of antibiogram susceptibility data. Antibiograms from across the United States were obtained by various methods, including direct mailings, Internet searches, and professional contacts. Each ABGM collected was analyzed using prospectively defined elements from the M39-A guidelines. Additionally, seven quality indicators were also evaluated to look for the reporting of any atypical or inappropriate susceptibility data. The 209 antibiograms collected from 149 institutions showed at least 85% compliance to 5 of the 10 M39-A elements analyzed. Clinically relevant elements not met included annual analysis, duplicate isolate notation, and the exclusion of organisms with fewer than 10 isolates. As for the quality indicators evaluated, unexpected results included the 7% of antibiograms that reported <100% vancomycin susceptibility for Staphylococcus aureus, 24% that had inconsistent beta-lactam susceptibility for Staphylococcus aureus, 20% that reported <100% imipenem susceptibility for Escherichia coli, and 37% that reported >0% ampicillin susceptibility for Klebsiella pneumoniae. These findings suggest that antibiograms should be reviewed thoroughly by infectious disease specialists (physicians and pharmacists), clinical microbiologists, and infection control personnel for identification of abnormal findings prior to distribution

Delivery Room Resuscitation and Short-Term Outcomes in Moderately Preterm Infants

ObjectivesTo describe the frequency and extent of delivery room resuscitation and evaluate the association of delivery room resuscitation with neonatal outcomes in moderately preterm (MPT) infants.Study designThis was an observational cohort study of MPT infants delivered at 290/7 to 336/7 weeks' gestational age (GA) enrolled in the Neonatal Research Network MPT registry. Infants were categorized into 5 groups based on the highest level of delivery room intervention: routine care, oxygen and/or continuous positive airway pressure, bag and mask ventilation, endotracheal intubation, and cardiopulmonary resuscitation including chest compressions and/or epinephrine use. The association of antepartum and intrapartum risk factors and discharge outcomes with the intensity of resuscitation was evaluated.ResultsOf 7014 included infants, 1684 (24.0%) received routine care and no additional resuscitation, 2279 (32.5%) received oxygen or continuous positive airway pressure, 1831 (26.1%) received bag and mask ventilation, 1034 (14.7%) underwent endotracheal intubation, and 186 (2.7%) received cardiopulmonary resuscitation. Among the antepartum and intrapartum factors, increasing GA, any exposure to antenatal steroids and prolonged rupture of membranes decreased the likelihood of receipt of all levels of resuscitation. Infants who were small for GA (SGA) had increased risk of delivery room resuscitation. Among the neonatal outcomes, respiratory support at 28 days, days to full oral feeds and length of stay were significantly associated with the intensity of delivery room resuscitation. Higher intensity of resuscitation was associated with increased risk of mortality.ConclusionsThe majority of MPT infants receive some level of delivery room resuscitation. Increased intensity of delivery room interventions was associated with prolonged respiratory and nutritional support, increased mortality, and a longer length of stay