Temporal changes in prevalence of antimicrobial resistance in 23 U.S. hospitals. (Research).Antimicrobial antimicrobial /an·ti·mi·cro·bi·al/ (-mi-kro´be-al) 1. killing microorganisms or suppressing their multiplication or growth. 2. an agent with such effects. resistance is increasing in nearly all health-care-associated pathogens. We examined changes in resistance prevalence during 1996-1999 in 23 hospitals by using two statistical methods. When the traditional chi-square test chi-square test: see statistics. of pooled mean resistance prevalence was used, most organisms appear to have increased in prevalence. However, when a more conservative test that accounts for changes within individual hospitals was used, significant increases in prevalence of resistance were consistently observed only for oxacillin-resistant Staphylococcus aureus Staphylococcus au·re·us n. A bacterium that causes furunculosis, pyemia, osteomyelitis, suppuration of wounds, and food poisoning. Staphylococcus aureus Staphylococcus pyogenes , ciprofloxacin-resistant Pseudomonas aeruginosa Pseudomonas aeruginosa A normal soil inhabitant and human saprophyte that may contaminate various solutions in a hospital, causing opportunistic infection in weakened Pts Clinical Infective endocarditis in IVDAs, RTIs, UTIs, bacteremia, meningitis, 'malignant' , and ciprofloxacin- or ofloxacin-resistant Escherichia coli Escherichia coli (ĕsh'ərĭk`ēə kō`lī), common bacterium that normally inhabits the intestinal tracts of humans and animals, but can cause infection in other parts of the body, especially the urinary tract. . These increases were significant only in isolates from patients outside intensive-care units (ICU ICU intensive care unit. ICU abbr. intensive care unit ICU see intensive care unit. ICU ). The increases seen are of concern; differences in factors present outside ICUs, such as excessive quinolone use or inadequate infection-control practices, may explain the observed trends. ********** The increasing prevalence of antimicrobial-resistant organisms, a major public health problem, is of particular concern for hospitals (1,2). However, resistance data aggregated from many hospitals document changes over time but often do not evaluate the consistency of these changes in all the hospitals (3-5). Several statistical tests can be used to evaluate changes in antimicrobial-resistance prevalence; chi-square is commonly used but does not account for consistency of trends in all hospitals. Thus, national or international evaluations based on observed changes in resistance patterns in isolates pooled from all sites can misrepresent mis·rep·re·sent tr.v. mis·rep·re·sent·ed, mis·rep·re·sent·ing, mis·rep·re·sents 1. To give an incorrect or misleading representation of. 2. the overall trend if a few of the sites report outlier outlier /out·li·er/ (out´li-er) an observation so distant from the central mass of the data that it noticeably influences results. outlier an extremely high or low value lying beyond the range of the bulk of the data. data, as had been observed with data from the National Nosocomial Infections Nosocomial infections Infections that were not present before the patient came to a hospital, but were acquired by a patient while in the hospital. Mentioned in: Enterobacterial Infections, Staphylococcal Infections Surveillance system (6). A second difficulty with interpreting data for U.S. trends of antimicrobial resistance in health-care settings is inherent in the diversity of populations served by the facilities. Monitoring resistance patterns by location within the hospital (e.g., intensive-care units [ICUs], non-ICU inpatient areas, and outpatient areas) can demonstrate substantial changes that would be obscured if hospitalwide data were aggregated into national trends. To determine consistency of changes in antimicrobial-resistance patterns over time in a national monitoring project, we used two statistical methods to evaluate national antimicrobial-resistance data over a 4-year period, as well as assess consistency within hospitals. Methods For this study, we monitored changes in antimicrobial resistance in different hospital areas during two periods (1996-1997 and 1998-1999) in facilities participating in Project ICARE ICARE International Cancer Alliance for Research and Education ICARE International Cancer Academy for Research and Education ICARE International Community Actively Responding to The Environment ICARE Informed Citizens Against Runway Expansion (Intensive Care Antimicrobial Resistance Epidemiology), a joint project of the Hospital Infections Program (now the Division of Healthcare Quality Promotion) of the Centers for Disease Control and Prevention Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. (CDC See Control Data, century date change and Back Orifice. CDC - Control Data Corporation ) and the Rollins School of Public Health The Rollins School of Public Health (RSPH) is the public health school of Emory University. Founded in 1990, RSPH has more than 850 students pursuing master's degrees (MPH/MSPH) and over 100 students pursuing doctorate degrees (PhD). of Emory University Emory University (ĕm`ərē), near Atlanta, Ga.; coeducational; United Methodist; chartered as Emory College 1836, opened 1837 at Oxford. It became Emory Univ. in 1915 and in 1919 moved to Atlanta. . Hospitals participating in the ICU surveillance component of the National Nosocomial Infections Surveillance (NNIS NNIS National Nosocomial Infection Surveillance System ) system were invited to participate in the second (January 1996 through December 1997) and third (April 1998 through July 1999) phases of Project ICARE. Twenty-three U.S. hospitals reported acceptable data for both time periods. The surveillance methods and definitions of the NNIS system and Project ICARE have been described (7,8). Each month, hospitals reported the antimicrobial-susceptibility results of isolates recovered from clinical specimens from patients served by the clinical microbiology Clinical microbiology The adaptation of microbiological techniques to the study of the etiological agents of infectious disease. Clinical microbiologists determine the nature of infectious disease and test the ability of various antibiotics to inhibit or kill laboratory. For study isolates, susceptibility results were reported from all clinical specimens, whether associated with hospital- or community-acquired infection or colonization colonization, extension of political and economic control over an area by a state whose nationals have occupied the area and usually possess organizational or technological superiority over the native population. . Duplicate isolates were excluded; these were defined as isolates of the same organism with the same antimicrobial-resistance pattern recovered from the same patient during a calendar month, regardless of the site of isolation (e.g., blood, sputum sputum /spu·tum/ (spu´tum) [L.] expectoration; matter ejected from the trachea, bronchi, and lungs through the mouth. sputum cruen´tum bloody sputum. , urine, wound). In addition, isolates obtained as part of infection-control surveillance were excluded. When these "surveillance" isolates are excluded, the resistance prevalence (i.e., percent resistant) more closely reflects data routinely aggregated as part of the laboratories' cumulative susceptibility reports (i.e., cumulative antibiograms). The validity of the susceptibility data has been assessed, and participating laboratories were evaluated as performing reliably. This assessment was done through a proficiency testing proficiency test n → prueba de capacitación program at these laboratories, as well as confirmatory testing of selected isolates (9). Susceptibility results (MIC and zone diameters) were interpreted according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. criteria from the National Committee for Clinical Laboratory Standards (NCCLS NCCLS National Committee for Clinical Laboratory Standards ) (10-12). The sentinel sentinel /sen·ti·nel/ (sen´ti-n'l) one who gives a warning or indicates danger. sentinel a recording mechanism, such as an animal, a farm or a veterinarian, posted explicitly to record a possible occurrence or series of organisms considered in the analysis, which represented frequently encountered resistance problems in U.S. hospitals, were oxacillin-resistant coagulase-negative staphylococci staph·y·lo·coc·cus n. pl. staph·y·lo·coc·ci A spherical gram-positive parasitic bacterium of the genus Staphylococcus, usually occurring in grapelike clusters and causing boils, septicemia, and other infections. , oxacillin-resistant Staphylococcus aureus (ORSA ORSA Operations Research Society of America ORSA Occupational Road Safety Alliance (UK) ORSA Own Risk and Solvency Assessment ORSA Oxacillin Resistant Staph Aureus ORSA Operations Research & System Analysis ), vancomycin-resistant enterococci enterococci bacteria in the genus Enterococcus. (VRE VRE vancomycin-resistant enterococcus. VRE Vancomycin-resistent enterococcus, see there ), third-generation cephalosporin-resistant Escherichia coil, third-generation cephalosporin-resistant Enterobacter species, ceftazidime-resistant Pseudomonas aeruginosa, ciprofloxacin-resistant P aeruginosa, ciprofloxacin-resistant E. coli E. coli: see Escherichia coli. E. coli in full Escherichia coli Species of bacterium that inhabits the stomach and intestines. E. coli can be transmitted by water, milk, food, or flies and other insects. (for E. coli, defined as resistance to either ofloxacin or ciprofloxacin ciprofloxacin /cip·ro·flox·a·cin/ (sip?ro-flok´sah-sin) a synthetic antibacterial effective against many gram-positive and gram-negative bacteria; used as the hydrochloride salt. cip·ro·flox·a·cin n. ), and third-generation cephalosporin-resistant Klebsiella pneumoniae Klebsiella pneu·mo·ni·ae n. Friedlander's bacillus. . These data were aggregated for each month and stratified stratified /strat·i·fied/ (strat´i-fid) formed or arranged in layers. strat·i·fied adj. Arranged in the form of layers or strata. by hospital area and time period. To determine temporal trends, we compared all data reported from isolates tested during 1996-1997 (period 1) with all data reported from isolates tested during 1998-1999 (period 2). Data were reported for each hospital area, including each separate ICU (units that provide intensive observation, diagnosis, and therapeutic procedures for critically ill patients); as a pooled total for a given hospital's non-ICU inpatient areas (areas other than ICUs where the patient stays at least one night in the hospital); and as a pooled total for each hospital's outpatient areas (urgent care or emergency wards and units that perform same-day surgery same-day surgery Managed care Any operation which, in absence of complications may be provided at a hospital on an outPt basis. See ASC surgical services. or simple diagnostic procedures and therapy, such as chemotherapy, hemodialysis hemodialysis /he·mo·di·al·y·sis/ (-di-al´i-sis) removal of certain elements from the blood by virtue of the difference in rates of their diffusion through a semipermeable membrane while being circulated outside the body; the process , or cardiac catheterization Cardiac Catheterization Definition Cardiac catheterization (also called heart catheterization) is a diagnostic procedure which does a comprehensive examination of how the heart and its blood vessels function. ). Pooled rates were calculated for prevalence of resistance (e.g., percent VRE = proportion of enterococci tested that were resistant to vancomycin vancomycin (văn'kōmī`sĭn), antibiotic resembling penicillin in the way it acts. It is derived from the bacterium Streptomyces orientalis, which was isolated from soil of India and Indonesia. ) at each hospital. If <10 isolates were tested for antimicrobial susceptibility from a specific hospital area during the study period, the prevalence rate was considered to be of low accuracy, and that hospital area was excluded from further analysis. To assess the overall magnitude of resistance for each sentinel organism, we calculated an overall (i.e., weighted mean) pooled mean prevalence, combining data from all hospitals, by hospital area and time period. Changes in resistance prevalence over time within each hospital area were assessed by chi-square tests. In addition, each hospital's change in resistance prevalence over time for each sentinel organism was determined by subtracting the period 2 rate from the period 1 rate. Since the changes in resistance rates for most organisms did not follow a normal distribution, a nonparametric test was used to assess the statistical significance of the temporal changes. The Wilcoxon signed-rank test The Wilcoxon signed-rank test is a non-parametric alternative to the paired Student's t-test for the case of two related samples or repeated measurements on a single sample. was chosen for the analysis to take into account the variability of resistance patterns in individual hospitals while minimizing the impact of hospitals with extreme (outlying) values of temporal changes in resistance. The signed-rank test is used to assess the null hypothesis null hypothesis, n theoretical assumption that a given therapy will have results not statistically different from another treatment. null hypothesis, n that the population median of the differences in paired observations is equal to zero (13). Since the focus is on medians rather than means, extreme values are less likely to influence the outcome of this test, unlike a t test of the pooled mean values. P values <0.05 were considered significant. Results Of 61 hospitals reporting some data to Project 1CARE in either period, 23 (38%) reported at least 6 months of data during both periods and were included in this analysis. Twenty-one (91%) were general hospitals, and 2 (9%) were Veterans Administration hospitals. Fifteen (65%) were affiliated with a medical school. The mean size of participating hospitals was 440 beds (median 356, range 147-1,022); 13 (56%) were in the Atlantic Region, 6 (26%) in the Central Region, 2 (9%) in the New England New England, name applied to the region comprising six states of the NE United States—Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut. The region is thought to have been so named by Capt. Region, and 2 (9%) in the Pacific Region. Study hospitals (n=23) did not differ significantly in these characteristics from the ICARE hospitals that were excluded from analysis (n=38) because they submitted data for only one of the two time periods. The overall pooled mean prevalence of resistance from period I to period 2 appeared to have changed for most of the sentinel organisms. The changes were statistically significant when compared by a chi-square test of the pooled means, by time period, for five sentinel organisms in the ICU areas, five in the non-ICU areas, and four in the outpatient areas (Table, footnote). However, when the temporal change in prevalence was evaluated by comparing the median difference in prevalence between period 1 and period 2, no organism demonstrated a significant temporal change in prevalence in the ICUs (Table). In addition, temporal changes remained significant for only three of the sentinel organisms in the non-ICU inpatient area and four in the outpatient area. In non-ICU inpatient areas, significant increases in median resistance rates were noted for ORSA (8.2%), ciprofloxacin-resistant P aeruginosa (3.3%), and ciprofloxacin-resistant E. coli (0.6%) (Table). In outpatient areas, significant increases in median resistance rates were evident for ORSA (2.4%), VRE (0.6%), ciprofloxacin-resistant E. coil (1.0%), and ciprofloxacin-resistant P. aeruginosa (5.0%) (Table). No significant change in resistance prevalence was observed for oxacillin-resistant coagulase-negative staphylococci, third-generation cephalosporin-resistant E. coli, third-generation cephalosporin-resistant Enterobacter species, or ceftazidime-resistant P. aeruginosa in ICU, non-ICU inpatient, or outpatient areas. Discussion These data, which demonstrate a high level of antimicrobial resistance in organisms commonly associated with hospital-acquired infections Hospital-Acquired Infections Definition A hospital-acquired infection is usually one that first appears three days after a patient is admitted to a hospital or other health care facility. , are consistent with other reports (35,14). However, in this analysis of data from 23 hospitals for 1996-1999, we demonstrate that antimicrobial resistance in the study hospitals has increased consistently for only a few of the sentinel organisms measured. Significant increases were limited to ORSA, ciprofloxacin-resistant P aeruginosa, and ciprofloxacin- or ofloxacin-resistant E. coli. Furthermore, these increases were significant only for isolates obtained from non-ICU unit areas. If the traditional chi-square test, which uses the pooled mean prevalence rate, is used to determine the level of significance, significant increases appear to have occurred in most of the organisms studied and throughout the hospital. However, these overall changes in prevalence often were influenced by weighting of the pooled mean by a few hospitals reporting larger numbers of isolates or very large increases in antimicrobial-resistance prevalence. The data from these influential hospitals were not representative of what was observed ill most of the hospitals. Thus, the more conservative statistical test used, the Wilcoxon signed-rank test, identified those hospital areas and sentinel organisms where the temporal change was more representative of all the hospitals. By using the more conservative assessment of median differences between time periods, we were able to present a more valid scenario of observations across most of our study hospitals. The paired t test, which tests whether the mean difference in resistance prevalence is equal to zero, is also a viable alternative for analysis of data such as these, provided that sample sizes are large enough to justify the assumption that the differences are normally distributed. If uncertainty exists about the normal distribution, the Wilcoxon signed-rank test is a good choice, since it performs almost as well as the t test when the data are normally distributed. Although the prevalence of ORSA has not increased in the ICUs of these hospitals, the increase in prevalence of ORSA outside ICUs is very concerning. S. aureus The aureus (pl. aurei) was a gold coin of ancient Rome valued at 25 silver denarii. The aureus was regularly issued from the 1st century BC to the beginning of the 4th century AD, when it was replaced by the solidus. is commonly seen with central line-associated bloodstream or surgical site infection (15). The median increase of 2.4% in isolates from the outpatient areas is approximately a 10% increase over the baseline prevalence observed in the first time period (i.e., 20% ORSA). Although these isolates are mostly from emergency room patients who likely have had recent exposures to healthcare settings, this prevalence rate is comparable with the rate of 20%-23% observed in hospitalized patients in the early 1990s (16). With more frequent reports of community-onset ORSA infections (17-19), we expect this prevalence rate to continue to increase unless adequate prevention measures are identified and implemented. Gram-negative bacilli bacilli /ba·cil·li/ (bah-sil´i) plural of bacillus. bacilli see bacillus. are frequently associated with hospital-acquired infections, particularly ventilator-associated pneumonia Ventilator-associated pneumonia (VAP) is a sub-type of hospital-acquired pneumonia (HAP) which occurs in people who are on mechanical ventilation through an endotracheal or tracheostomy tube for at least 48 hours. and catheter-associated urinary tract infections urinary tract infection (UTI), n infection in one or more of the structures that make up the urinary system. Occurs more often in women and is most commonly caused by bacteria. (15,20). Although antimicrobial resistance in these organisms to third-generation cephalosporins Cephalosporins Definition Cephalosporins are medicines that kill bacteria or prevent their growth. Purpose Cephalosporins are used to treat infections in different parts of the body—the ears, nose, throat, lungs, sinuses, and is of great clinical concern (4,21,22), no consistent increases occurred in prevalence of third-generation cephalosporin cephalosporin (sĕf'əlōspôr`ĭn), any of a group of more than 20 antibiotics derived from species of fungi of the genus Cephalosporium and closely related chemically to penicillin. Cephalosporins, e.g. resistance in E. coli, Enterobacter spp., K. pneumoniae, or P. aeruginosa. This finding does not imply that some hospitals did not experience significant increases, but rather that changes over time were not consistent between facilities in all hospital areas. This observation may reflect successful infection-control strategies in study hospitals, but further study is needed to validate this conjecture CONJECTURE. Conjectures are ideas or notions founded on probabilities without any demonstration of their truth. Mascardus has defined conjecture: "rationable vestigium latentis veritatis, unde nascitur opinio sapientis;" or a slight degree of credence arising from evidence too weak or too . For K. pneumoniae or E. coli, these data suggest that ESBL-producing K. pneumoniae or E. coli remains a focal problem. The data are strikingly different for ciprofloxacin resistance in P. aeruginosa and E. coli. With these organisms, resistance from non-ICU patient isolates and outpatient isolates increased across all hospitals, but resistance in the ICU patient isolates did not increase significantly. Contributing factors may include the large amounts of quinolones used by patients outside the ICU or the development of ciprofloxacin resistance in P aeruginosa unrelated to the ICU setting (23). No consistent increases in resistance were observed in ICU isolates for any of the study organisms, which may reflect successful infection-control programs in the ICUs at these study hospitals. However, this finding also might reflect a variation in the evolution of antimicrobial resistance at these hospitals. For example, the prevalence of antimicrobial resistance increased first in the ICUs, and factors similar to those in the ICUs have moved into the non-ICU areas, resulting in increases in these areas during the second half of the study. One major limitation of this study is the small size of this national sample. With only 23 hospitals reporting sufficient data in each study period, inferences from these data about the direction of antimicrobial resistance in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. overall must be made with caution. Although these hospitals are representative of all NNIS hospitals, hospitals in the Mid- and South-Atlantic regions are overrepresented o·ver·rep·re·sent·ed adj. Represented in excessive or disproportionately large numbers: "Some groups, and most notably some races, may be overrepresented and others may be underrepresented" (24). However, statistically significant trends of increasing resistance for ORSA and ciprofloxacin-resistant P aeruginosa or E. coli, found using a conservative test for significance, suggest that these changes are consistent in all study hospitals. This finding may indicate that these resistant organisms represent problems faced by most U.S. hospitals. Another limitation is lack of confirmation of the clinical relevance of the organisms evaluated in this study, which represent organisms associated both with colonization and infection. However, we minimized inclusion of colonizing organisms by eliminating duplicate reports. In addition, in a separate analysis of these surveillance data, we have demonstrated that the cumulative susceptibility reports generated from these data are comparable with those for organisms reported to be associated with definitive hospital-acquired infection (25). Therefore, we believe the data in this study are representative of the susceptibilities of the organisms associated with hospital-acquired infections. These data suggest that monitoring antimicrobial resistance by hospital area can identify national trends in resistance prevalence affecting only certain hospital areas. Increases are also widespread in study hospitals in patients outside the ICU. Attention should be paid to identifying novel measures for curbing increases in antimicrobial resistance outside ICUs and to assessing why current measures are failing. Aggregated susceptibility data, such as those presented here, may be easily obtained as part of local or regional surveillance efforts. Written guidelines for producing cumulative susceptibility reports from hospital-based surveillance efforts have been created by the National Committee for Clinical Laboratory Standards (26). Public health authorities can use such data produced by standard specifications to assess trends in prevalence of antimicrobial-resistant organisms associated with health-care delivery. However, analysis of temporal trends should include assessing consistency of changes in the facilities under surveillance by using appropriate statistical tests.
Table. Weighted pooled mean prevalence and temporal differences of
antimicrobial resistance for sentinel organisms, 1996-1999, Project
ICARE hospitals
Weighted pooled mean
resistance rate (%)
Antimicrobial-Resistant Pathogen 1996-1997 1998-1999
Intensive-care unit areas
Oxacillin-resistant CNS 76.0 73.6
Oxacillin-resistant Staphylococcus aureus 30.9 35.6 (c)
Vancomycin-resistant enterococcus 15.5 15.0
Cef3-resistant Escherichia coli 0.57 2.2 (c)
Cef3-resistant Enterobacter spp. 25.2 25.0
Ceftazidime-resistant P. aeruginosa 8.3 7.8
Ciprofloxacin-resistant P. aeruginosa 17.7 24.4 (c)
Ciprofloxacin-resistant E. coli 0.9 2.0 (c)
Cef3-resistant Klebsiella pneumoniae 2.4 8.4 (c)
Non-intensive-care unit inpatient areas
Oxacillin-resistant CNS 62.6 63.6
Oxacillin-resistant Staphylococcus aureus 30.2 34.4 (c)
Vancomycin-resistant enterococcus 13.9 11.3
Cef3-resistant Escherichia coli 0.69 0.53
Cef3-resistant Enterobacter spp. 22.1 20.5
Ceftazidime-resistant P. aeruginosa 5.8 5.9
Ciprofloxacin-resistant P. aeruginosa 17.2 23.9 (c)
Ciprofloxacin-resistant E. coli 1.4 2.5 (c)
Cef3-resistant K. pneumoniae 3.6 4.9 (c)
Outpatient/urgent/emergent care patients
Oxacillin-resistant CNS 45.2 43.6
Oxacillin-resistant Staphylococcus aureus 18.0 22.6 (c)
Vancomycin-resistant enterococcus 2.1 4.8 (c)
Cef3-resistant Escherichia coli 0.16 0.23
Cef3-resistant Enterobacter spp. 10.0 9.2
Ceftazidime-resistant P. aeruginosa 3.8 3.6
Ciprofloxacin-resistant P. aeruginosa 20.0 24.6 (c)
Ciprofloxacin-resistant E. coli 0.61 1.4 (c)
Cef3-resistant K. pneumoniae 1.1 1.5
Median difference (%) in
Antimicrobial-Resistant Pathogen resistance rates (a)
Intensive-care unit areas
Oxacillin-resistant CNS -0.01
Oxacillin-resistant Staphylococcus aureus 1.83
Vancomycin-resistant enterococcus -1.81
Cef3-resistant Escherichia coli 0.00
Cef3-resistant Enterobacter spp. -2.08
Ceftazidime-resistant P. aeruginosa 0.37
Ciprofloxacin-resistant P. aeruginosa 0.63
Ciprofloxacin-resistant E. coli 0.00
Cef3-resistant Klebsiella pneumoniae 0.00
Non-intensive-care unit inpatient areas
Oxacillin-resistant CNS 0.41
Oxacillin-resistant Staphylococcus aureus 8.20
Vancomycin-resistant enterococcus 0.93
Cef3-resistant Escherichia coli 0.00
Cef3-resistant Enterobacter spp. -5.90
Ceftazidime-resistant P. aeruginosa 0.00
Ciprofloxacin-resistant P. aeruginosa 3.30
Ciprofloxacin-resistant E. coli 0.57
Cef3-resistant K. pneumoniae 0.06
Outpatient/urgent/emergent care patients
Oxacillin-resistant CNS 11.50
Oxacillin-resistant Staphylococcus aureus 2.40
Vancomycin-resistant enterococcus 0.61
Cef3-resistant Escherichia coli 0.00
Cef3-resistant Enterobacter spp. -0.77
Ceftazidime-resistant P. aeruginosa 0.16
Ciprofloxacin-resistant P. aeruginosa 5.00
Ciprofloxacin-resistant E. coli 1.00
Cef3-resistant K. pneumoniae 0.00
Antimicrobial-Resistant Pathogen N p value (b)
Intensive-care unit areas
Oxacillin-resistant CNS 20 0.8
Oxacillin-resistant Staphylococcus aureus 22 0.4
Vancomycin-resistant enterococcus 20 0.9
Cef3-resistant Escherichia coli 20 0.3
Cef3-resistant Enterobacter spp. 17 0.4
Ceftazidime-resistant P. aeruginosa 21 0.9
Ciprofloxacin-resistant P. aeruginosa 22 0.2
Ciprofloxacin-resistant E. coli 20 1.0
Cef3-resistant Klebsiella pneumoniae 18 0.3
Non-intensive-care unit inpatient areas
Oxacillin-resistant CNS 20 0.6
Oxacillin-resistant Staphylococcus aureus 22 0.008
Vancomycin-resistant enterococcus 22 0.4
Cef3-resistant Escherichia coli 20 0.9
Cef3-resistant Enterobacter spp. 21 0.4
Ceftazidime-resistant P. aeruginosa 21 0.9
Ciprofloxacin-resistant P. aeruginosa 22 0.02
Ciprofloxacin-resistant E. coli 22 0.008
Cef3-resistant K. pneumoniae 20 0.1
Outpatient/urgent/emergent care patients
Oxacillin-resistant CNS 21 0.4
Oxacillin-resistant Staphylococcus aureus 22 0.009
Vancomycin-resistant enterococcus 21 0.02
Cef3-resistant Escherichia coli 22 0.7
Cef3-resistant Enterobacter spp. 21 0.6
Ceftazidime-resistant P. aeruginosa 21 0.7
Ciprofloxacin-resistant P. aeruginosa 21 0.02
Ciprofloxacin-resistant E. coli 22 <0.001
Cef3-resistant K. pneumoniae 20 0.5
(a) Median of the differences in resistance prevalence from period 1
(1996-1997) to period 2 (1998-1999) observed in the (N) hospitals or
units reporting resistance information on [greater than or equal to] 10
isolates for each of the time periods. CNS, coagulase-negative
Staphylococcus; Cef3, ceftazidime, cefotaxime, or ceftriaxone; for E.
coli, ciprofloxacin resistance is resistance to either ciprofloxacin
or ofloxacin.
(b) p value by Wilcoxon signed-rank test of the differences at N
hospitals or units.
(c) p<0.05 by chi-square test of pooled mean resistance rates between
time periods.
Acknowledgments We thank the infection-control and microbiology microbiology: see biology. microbiology Scientific study of microorganisms, a diverse group of simple life-forms including protozoans, algae, molds, bacteria, and viruses. personnel from the participating Intensive Care Antimicrobial Resistance Epidemiology (ICARE) Project hospitals for reporting the data for this study. This work was supported in part by grants to the Rollins School of Public Health of Emory University for Phases 2 and 3 of Project ICARE by AstraZeneca Pharmaceuticals (Wilmington, DE), Pfizer, Inc. (New York New York, state, United States New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of , NY), and Roche Laboratories (Nutley, NJ) as full sponsors, and Aventis Pharma (formerly Rhone-Poulenc Rorer) (Collegeville, PA), the National Foundation for Infectious Diseases infectious diseases: see communicable diseases. (Bethesda, MD), the American Society for Health Systems Pharmacists Research and Education Foundation (Bethesda, MD), Kimberly-Clark Corporation (Roswell, GA), and Bayer Corporation, Pharmaceuticals Division (West Haven West Haven, town (1990 pop. 54,021), New Haven co., S Conn., a suburb across the West River from New Haven; settled 1638, inc. as a separate borough 1873. Although mainly residential, there are diversified manufacturing industries. , CT) as partial sponsors. References (1.) McGowan JE Jr, Tenover FC. Control of antimicrobial resistance in the health care system. Infect Dis Clin North Am 1997;11:297-311. (2.) Schwartz B, Bell D, Hughes JM. Preventing the emergence of antimicrobial resistance: a call for action by clinicians, public health officials, and patients. JAMA JAMA abbr. Journal of the American Medical Association 1997;278:944-5. (3.) Deikema DJ, Pfaller MA, Schmitz FJ, Smayevsky J, Bell J, Jones RN, et al. Survey of infections due to Staphylococcus staphylococcus (stăf'ələkŏk`əs), any of the pathogenic bacteria, parasitic to humans, that belong to the genus Staphylococcus. The spherical bacterial cells (cocci) typically occur in irregular clusters [Gr. species: frequency of occurrence and antimicrobial susceptibility of isolates collected in the United States, Canada, Latin America Latin America, the Spanish-speaking, Portuguese-speaking, and French-speaking countries (except Canada) of North America, South America, Central America, and the West Indies. , Europe, and the Western Pacific Region for the SENTRY Antimicrobial Surveillance Program, 1997-1999. Clin Infect Dis 2001;32:S114-32. (4.) Gales AC, Jones RN, Turnidge J, Rennie R, Ramphal R. Characterization of Pseudomonas aeruginosa isolates: occurrence rates, antimicrobial susceptibility patterns, and molecular typing in the Global SENTRY Antimicrobial Surveillance Program, 1997-1999. Clin Infect Dis 2001;32:S146-55. (5.) Low DE, Keller N, Barth A, Jones RN. Clinical prevalence, antimicrobial susceptibility, and geographic resistance patterns of enterococci: results from the SENTRY Antimicrobial Surveillance Program, 1997-1999. Clin Infect Dis 2001;32:S133-45. (6.) Monnet D, Biddle JW, Edwards JR, Culver cul·ver n. A dove or pigeon. [Middle English, from Old English culufre, from Vulgar Latin *columbra, from Latin columbula, diminutive of columba, dove.] DH, Tolson JS, Martone W J, et al. Evidence of interhospital transmission of extended-spectrum [beta]-lactam-resistant Klebsiella pneumoniae in the United States, 1986-1993. Infect Control Hosp Epidemiol 1997;18:492-8. (7.) Emori G, Culver DH, Horan TC, Jarvis WR, Olson DR, Banerjee S, et al. National nosocomial infections surveillance (NNIS): Description of surveillance methods. Am J Infect Control 1991;19:19-35. (8.) Fridkin SK, Steward CD, Edwards JR, McGowan JE Jr, Culver DH, Gaynes RP, et al. Surveillance of antimicrobial use and antimicrobial resistance in U.S. hospitals: Project ICARE Phase 2. Clin Infect Dis 1999;29:245-52. (9.) Steward CD, Wallace D, Hubert SK, Lawton R, Fridkin SK, Gaynes RP, et al. Ability of laboratories to detect emerging antimicrobial resistance in nosocomial nosocomial /noso·co·mi·al/ (nos?o-ko´me-il) pertaining to or originating in a hospital. nos·o·co·mi·al adj. 1. Of or relating to a hospital. 2. pathogens: a survey of Project ICARE laboratories. Diagn Microbiol Infect Dis 2000;38:59-67. (10.) National Committee for Clinical Laboratory Standards. Performance standards for antimicrobial disk susceptibility tests susceptibility test Antimicrobial susceptibility test, see there . NCCLS approved standard M2-A6. Wayne (PA): The Committee; 1997. (11.) National Committee for Clinical Laboratory Standards. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically. NCCLS approved standard M7-A4. Wayne (PA): The Committee; 1997. (12.) National Committee for Clinical Laboratory Standards. Performance standards for antimicrobial susceptibility testing. NCCLS approved standard M 100-S6. Wayne (PA): The Committee; 1995. (13.) Mendenhall W, Wackerly DD, Schaeffer RL. Mathematical statistics Mathematical statistics uses probability theory and other branches of mathematics to study statistics from a purely mathematical standpoint. Mathematical statistics is the subject of mathematics that deals with gaining information from data. with applications. Belmont (CA): PWS-KENT Publishing Company; 1990. (14.) Pfaller MA, Jones RN, Messer SA, Edmond MB, Wenzel RP. National surveillance of nosocomial blood stream infection due to Candida albicans Candida albicans, n a pathogenic yeast, which is the causal agent of thrush, vaginal infections, and systemic candidiasis. Candida albicans : frequency of occurrence and antifungal antifungal /an·ti·fun·gal/ (-fung´gal) 1. destructive to fungi, or suppressing their reproduction or growth; effective against fungal infections. 2. an agent that so acts. susceptibility in the SCOPE Program. Diagn Microbiol Infect Dis 1998;31:327-32. (15.) Fridkin SK, Welbel SF, Weinstein RA. Magnitude and prevention of nosocomial infections in the intensive care unit. Infect Dis Clin North Am 1997;11:479-96. (16.) Fridkin SK, Gaynes RP. Antimicrobial resistance in intensive care units. Clin Chest Med 1999;20:303-16. (17.) Boyce JM. Are the epidemiology and microbiology of methicillin-resistant Staphylococcus aureus methicillin-resistant Staphylococcus aureus Methicillin-aminoglycoside resistant Staphylococcus aureus, MRSA An organism with multiple antibiotic resistances–eg, aminoglycosides, chloramphenicol, clindamycin, erythromycin, rifampin, tetracycline, changing? JAMA 1998;279:623-4. (18.) Centers for Disease Control and Prevention. Four pediatric pediatric /pe·di·at·ric/ (pe?de-at´rik) pertaining to the health of children. pe·di·at·ric adj. Of or relating to pediatrics. deaths from community-acquired methicillin-resistant Staphylococcus aureus--Minnesota and North Dakota North Dakota, state in the N central United States. It is bordered by Minnesota, across the Red River of the North (E), South Dakota (S), Montana (W), and the Canadian provinces of Saskatchewan and Manitoba (N). , 1997-1999. MMWR MMWR Morbidity & Mortality Weekly Report Epidemiology A news bulletin published by the CDC, which provides epidemiologic data–eg, statistics on the incidence of AIDS, rabies, rubella, STDs and other communicable diseases, causes of mortality–eg, Morb Mortal Wkly Rep 1999;48:707-10. (19.) Herold BC, Immergluck LC, Maranan MC, Lauderdale DS, Gaskin gaskin the muscular portion of the hindleg between the stifle and hock, corresponding to the human calf. The term is used in horses and sometimes dogs. RE, Boyle-Vavra S, et al. Community-acquired methicillin-resistant Staphylococcus aureus in children with no identified predisposing risk. JAMA 1998;279:593-8. (20.) Centers for Disease Control and Prevention. National Nosocomial Infections Surveillance (NNIS) report, data summary from January 1990-May 1999. Am J Infect Control 1999;27:520-32. (21.) Karas Karas may refer to:
(22.) Rice LB, Eckstein EC, DeVente J, Shlaes DM. Ceftazidime-resistant Klebsiella pneumoniae isolates recovered at the Cleveland Department of Veterans Affairs Veterans Affairs is a term of the business that deals with the relation between a government and its veteran communities, usually administered by the designated government agency. Medical Center. Clin Infect Dis 1996;23:118-24. (23.) McCaig LF, Hughes JM. Trends in antimicrobial drug prescribing in office-based physicians in the United States. JAMA 1995;273:214-9. (24.) Richards C, Emori G, Edwards JR, Fridkin SK, Tolson JS, Gaynes RP, et al. Characteristics of hospitals and infection control professionals participating in the National Nosocomial Infections Surveillance System 1999. Am J Infect Control 2001;29:400-3. (25.) Fridkin SK, Edwards JR, Tenover FC, Gaynes RP, McGowan JE Jr. Antimicrobial resistance prevalence rates in hospital antibiograms reflect prevalence rates in pathogens associated with hospital-acquired infections. Clin Infect Dis 2001;33:324-30 (26.) National Committee for Clinical Laboratory Standards. M39 analysis and presentation of cumulative antimicrobial susceptibility test data. The Committee. In press, 2002. Dr. Fridkin is a medical epidemiologist in the Division of Healthcare Quality Promotion (formerly the Hospital Infections Program), National Center for Infectious Diseases, Centers for Disease Control and Prevention. He works primarily on antimicrobial-resistance initiatives, including surveillance of antimicrobial resistance in health care, identification and control of antimicrobial-resistant infections, and outbreak investigations involving new and emerging antimicrobial-resistant pathogens in health-care settings. Scott K. Fridkin, * Holly A. Hill, ([dagger]) Nataliya V. Volkova, ([dagger]) Jonathan R. Edwards, * Rachel M. Lawton, * Robert P. Gaynes, * John E. McGowan, Jr., ([dagger]) and the Intensive Care Antimicrobial Resistance Epidemiology (ICARE) Project Hospitals * Centers for Disease Control and Prevention, Atlanta, Georgia, USA; and ([dagger]) Emory University, Atlanta, Georgia, USA Address for correspondence: Scott K. Fridkin, Division of Healthcare Quality Promotion, Mailstop A35, Centers for Disease Control and Prevention, 1600 Clifton Road Clifton Road is main street in Clifton neighborhood of Saddar Town in Karachi, Sindh, Pakistan. Its name dates from the British Colonial rule, and its market is posh areas of Karachi. , Atlanta, GA 30333, USA; fax: 404-639-6458; e-mail: skf0@cdc.gov |
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