Bowel colonization with vancomycin-resistant enterococci after antimicrobial therapy for intra-abdominal infections: observations from 2 randomized comparative clinical trials of ertapenem therapy.

The impact of different antimicrobial regimens for intra-abdominal infections on the frequency of bowel colonization with vancomycin-resistant enterococci (VRE) was examined in 2 randomized open-label trials of intra-abdominal infection comparing piperacillin-tazobactam or ceftriaxone/metronidazole with ertapenem. In these short-term studies, overall rates of bowel colonization with VRE were generally comparable after treatment with piperacillin-tazobactam, ceftriaxone/metronidazole, or ertapenem.

In vitro susceptibilities of aerobic and facultative gram-negative bacilli isolated from patients with intra-abdominal infections worldwide: the 2002 Study for Monitoring Antimicrobial Resistance Trends (SMART).

BACKGROUND: The Study for Monitoring Antimicrobial Resistance Trends (SMART) was begun in 2002 to monitor international drug-resistance patterns among aerobic and facultative gram-negative bacilli isolated from patients with intra-abdominal infections. METHODS: In 2002, 40 medical centers from 17 countries collected consecutive non-duplicate isolates from intra-abdominal infections for susceptibility testing against 12 antimicrobial agents using the broth microdilution methods recommended by the Clinical and Laboratory Standards Institute (formerly the National Committee for Clinical Laboratory Standards). RESULTS: A total of 3,134 aerobic and facultative gram-negative bacilli were isolated. Enterobacteriaceae accounted for 82% of the total and were most consistently susceptible to amikacin and the carbapenems. Escherichia coli (45%) and Klebsiella spp. (17%) were the most common species. The susceptibility rates of these organisms to the 12 antimicrobial agents differed among geographic regions, with isolates from the Asia/Pacific and Latin American regions usually having the highest rates of resistance. Ampicillin/sulbactam was the agent least frequently active against E. coli (56% susceptible) and Klebsiella spp. (73% susceptible). Extended-spectrum beta-lactamases (ESBLs) were detected phenotypically in 7% of E. coli, 13% of Klebsiella spp., and 18% of Enterobacter spp. Producers of ESBL overall had a more antibiotic-resistant profile than non-producers but were usually susceptible to carbapenems. CONCLUSIONS: Antimicrobial resistance rates among gram-negative bacilli isolated from intra-abdominal infections differed among geographic regions. The carbapenems were consistently active in vitro against Enterobacteriaceae worldwide, including ESBL producers.

Ertapenem as initial antimicrobial monotherapy for patients with chronic obstructive pulmonary disease hospitalized with typical community-acquired pneumonia.

This report describes a post-hoc analysis of two large studies of typical community-acquired pneumonia (CAP) in hospitalized patients, focusing on demographics, disease characteristics, and outcome in patients with and without chronic obstructive pulmonary disease (COPD). In both studies, ertapenem 1 g IV daily was compared with ceftriaxone 1 g IV daily as initial antimicrobial therapy. Clinically improving patients could be switched to oral antibiotic therapy after 3 days. Of the 857 patients treated in both studies, 264 (31%) had COPD. The proportions of patients who were male, were >/=65 years of age, had a Pneumonia Severity Index of IV/V, or had Haemophilus influenzae isolated in a baseline culture were higher in patients with COPD. Streptococcus pneumoniae was the most common pathogen both in patients with and without COPD. Clinical response rates in assessable patients 7-14 days after completion of therapy for the combined treatment groups were 90% (187/208) for patients with COPD and 93% (424/456) for those without COPD (odds ratio 0.7 [95% CI, 0.4-1.2], P = 0.17). Of assessable COPD patients, 109/121 (90%) treated with ertapenem and 78/87 (90%) treated with ceftriaxone achieved a favorable clinical response (odds ratio 1.0 [95% CI, 0.6-1.8], P = 0.94). The outcome in patients with or without COPD was similar regardless of therapy. In patients with COPD as well as in the overall study population, the efficacy of ertapenem as initial antimicrobial monotherapy for patients with serious typical community-acquired pneumonia was comparable to that of ceftriaxone.

Safety and tolerability of ertapenem.

Ertapenem is a Group 1 carbapenem that was licensed in the USA in November 2001 and in Europe in April 2002. Its safety profile has been assessed in 240 healthy volunteers participating in 12 clinical pharmacology studies and in 2046 patients enrolled in five Phase IIa and eight Phase IIb/III clinical trials. The most common drug-related adverse events (AEs) reported in trials comparing ertapenem and piperacillin-tazobactam and in trials comparing ertapenem and ceftriaxone were: diarrhoea (ertapenem versus piperacillin-tazobactam 5.0% versus 7.0%; ertapenem versus ceftriaxone 5.6% versus 5.9%); infused vein complications (ertapenem versus piperacillin-tazobactam 4.5% versus 7.9%; ertapenem versus ceftriaxone 3.2% versus 4.6%); nausea (ertapenem versus piperacillin-tazobactam 2.5% versus 3.4%; ertapenem versus ceftriaxone 3.4% versus 3.3%); and elevations in alanine aminotransferase levels (ertapenem versus piperacillin-tazobactam 8.8% versus 7.3%; ertapenem versus ceftriaxone 8.3% versus 6.9%). Most ertapenem-related AEs were reported as mild-to-moderate in intensity. Ertapenem was not associated with prolongation of the QTc interval. Local reactions of moderate-to-severe intensity at the infusion site were infrequent and occurred with similar frequency in the ertapenem and comparator treatment groups. No overall differences in safety were observed between elderly (aged > or = 65 years and > or = 75 years) and younger patients. Ertapenem, 1 g once a day given by intravenous infusion or intramuscular injection, was generally well tolerated and had overall safety and tolerability profiles similar to those of piperacillin-tazobactam and ceftriaxone.

Ertapenem therapy for community-acquired pneumonia in the elderly.

OBJECTIVES: To compare the efficacy and safety of ertapenem, 1 g once a day, with ceftriaxone, 1 g once a day, for treatment of the subgroup of patients aged 65 and older with community-acquired pneumonia (CAP) requiring parenteral therapy. DESIGN: Combined data from patients aged 65 and older in two randomized, double-blind clinical trials. SETTING: Eighty international centers. PARTICIPANTS: Eight hundred fifty-seven treated patients, of whom 351 were aged 65 and older. INTERVENTIONS: Intravenous or intramuscular ertapenem or ceftriaxone with the option to switch to oral amoxicillin-clavulanate after at least 3 days of parenteral therapy. MEASUREMENTS: Clinical efficacy was assessed at completion of parenteral therapy and 7 to 14 days after all therapy had been completed (test of cure (TOC) assessment). Bacterial eradication was assessed at the TOC visit. Safety was assessed daily during study therapy and for 14 days thereafter. RESULTS: One hundred forty-eight clinically evaluable patients aged 65 and older were treated with ertapenem and 125 with ceftriaxone. Pathogens were identified in 157 (57.5%) patients (the most common being Streptococcus pneumoniae), most of which were penicillin-susceptible. Clinical cure rates were 95.9% for patients in the ertapenem group and 92.7% for patients in the ceftriaxone group at completion of parenteral therapy and 93.9% and 90.4%, respectively, at the TOC assessment. Overall bacterial eradication rates were 92.8% (77 of 83) for patients treated with ertapenem and 93.2% (69 of 74) for those treated with ceftriaxone. The most common drug-related adverse experiences in both treatment groups were diarrhea and mild to moderate elevation of serum aminotransferase levels. CONCLUSION: Ertapenem 1 g once a day was highly effective for treatment of elderly patients with CAP requiring parenteral therapy and was as effective as ceftriaxone. Ertapenem was generally well tolerated, with an overall safety profile similar to ceftriaxone.

Surveillance for antimicrobial susceptibility among clinical isolates of Pseudomonas aeruginosa and Acinetobacter baumannii from hospitalized patients in the United States, 1998 to 2001.

Pseudomonas aeruginosa and Acinetobacter baumannii are the most prevalent nonfermentative bacterial species isolated from clinical specimens of hospitalized patients. A surveillance study of 65 laboratories in the United States from 1998 to 2001 found >90% of isolates of P. aeruginosa from hospitalized patients to be susceptible to amikacin and piperacillin-tazobactam; 80 to 90% of isolates to be susceptible to cefepime, ceftazidime, imipenem, and meropenem; and 70 to 80% of isolates to be susceptible to ciprofloxacin, gentamicin, levofloxacin, and ticarcillin-clavulanate. From 1998 to 2001, decreases in antimicrobial susceptibility (percents) among non-intensive-care-unit (non-ICU) inpatients and ICU patients, respectively, were greatest for ciprofloxacin (6.1 and 6.5), levofloxacin (6.6 and 3.5), and ceftazidime (4.8 and 3.3). Combined 1998 to 2001 results for A. baumannii isolated from non-ICU inpatients and ICU patients, respectively, demonstrated that >90% of isolates tested were susceptible to imipenem (96.5 and 96.6%) and meropenem (91.6 and 91.7%); fewer isolates from both non-ICU inpatients and ICU patients were susceptible to amikacin and ticarcillin-clavulanate (70 to 80% susceptible); and <60% of isolates were susceptible to ceftazidime, ciprofloxacin, gentamicin, or levofloxacin. From 1998 to 2001, rates of multidrug resistance (resistance to at least three of the drugs ceftazidime, ciprofloxacin, gentamicin, and imipenem) showed small increases among P. aeruginosa strains isolated from non-ICU inpatients (5.5 to 7.0%) and ICU patients (7.4 to 9.1%). From 1998 to 2001, rates of multidrug resistance among A. baumannii strains isolated from non-ICU inpatients (27.6 to 32.5%) and ICU patients (11.6 to 24.2%) were higher and more variable than those observed for P. aeruginosa. Isolates concurrently susceptible, intermediate, or resistant to both imipenem and meropenem accounted for 89.8 and 91.2% of P. aeruginosa and A. baumannii isolates, respectively, studied from 1998 to 2001. In conclusion, for aminoglycosides and most beta-lactams susceptibility rates for P. aeruginosa and A. baumannii were constant or decreased only marginally (

Trends in antimicrobial susceptibilities among Enterobacteriaceae isolated from hospitalized patients in the United States from 1998 to 2001.

Longitudinal surveillance of Enterobacteriaceae for antimicrobial susceptibility is important because species of this family are among the most significant and prevalent human pathogens. To estimate rates of in vitro antimicrobial susceptibility among hospitalized patients in the United States, data from The Surveillance Network were studied for 14 agents tested against 10 species of Enterobacteriaceae (n = 384,279) isolated from intensive-care-unit (ICU) patients and non-ICU inpatients from 1998 to 2001. Cumulative susceptibility (percent) data for all species of Enterobacteriaceae isolated from ICU patients and non-ICU inpatients, respectively, were ranked as follows: ampicillin-sulbactam (45.5 and 57.2) << ticarcillin-clavulanate (74.8 and 83.5) < trimethoprim-sulfamethoxazole (87.0 and 84.5) congruent with cefotaxime (82.9 and 92.6) = ceftazidime (82.3 and 91.0) = ceftriaxone (86.5 and 93.9) = piperacillin-tazobactam (83.5 and 90.5) < levofloxacin (89.3 and 90.6) = ciprofloxacin (91.0 and 91.7) < gentamicin (91.8 and 94.3) < cefepime (95.0 and 97.9) < amikacin (98.5 and 99.2) < imipenem (100 and 100) = meropenem (100 and 100). Of those agents studied only susceptibilities to ciprofloxacin (94 to 89%) and levofloxacin (93 to 89%) decreased in a stepwise manner from 1998 to 2001. Decreased fluoroquinolone susceptibility was most pronounced for Escherichia coli, Proteus mirabilis, and Enterobacter cloacae. For all species of Enterobacteriaceae, trimethoprim-sulfamethoxazole resistance was more commonly observed in isolates with a single-drug resistance phenotype while gentamicin and fluoroquinolone resistances were more common in isolates resistant to at least one additional class of antimicrobial agent. Ongoing surveillance of Enterobacteriaceae will be particularly important to monitor changes in fluoroquinolone susceptibility, as well as changes in the prevalence of isolates resistant to multiple classes of antimicrobial agents.

Use of surrogate antimicrobial agents to predict susceptibility to ertapenem.

Broth or agar dilution susceptibility test results for Enterobacteriaceae (11,775 strains), anaerobes (2888 strains), staphylococci (2206 strains), Haemophilus spp. (840 strains), group A streptococci (280 strains), group B streptococci (269 strains), Streptococcus pneumoniae (709 strains), and 160 other streptococci were analyzed to identify surrogate antimicrobial agents to predict susceptibility to ertapenem. Ertapenem MIC interpretive categories approved by the United States FDA were compared to those of imipenem, oxacillin (staphylococci), or penicillin (streptococci). Ertapenem resistance was rare (1.2%) among 8187 consecutively collected clinical isolates of Enterobacteriaceae, including a large proportion of isolates from intensive care units. Absolute categorical agreement between ertapenem and imipenem, and very major (false susceptible) and major errors (false resistant) using imipenem to predict ertapenem results were 97.2%, 0.9%, and 0.4%, respectively, for Enterobacteriaceae (10,992 strains tested against both drugs) and 99.0%, 0.2%, and 0% for anaerobes. All Haemophilus spp., groups A and B streptococci, penicillin-susceptible and -intermediate S. pneumoniae, and other penicillin-susceptible streptococci were susceptible to ertapenem. All oxacillin-susceptible Staphylococcus aureus were ertapenem susceptible, except 1 that was intermediate. Surrogate antimicrobial agents that can be used to reliably predict ertapenem susceptibility by MIC tests are imipenem for Enterobacteriaceae and anaerobes, oxacillin for staphylococci, and penicillin for streptococci.

A study evaluating the efficacy, safety, and tolerability of ertapenem versus ceftriaxone for the treatment of community-acquired pneumonia in adults.

In a double-blind, multicenter trial, 502 patients hospitalized with community-acquired pneumonia were randomized to receive therapy with either ertapenem or ceftriaxone (for each, 1 g given intravenously once daily). After a minimum of 3 days, therapy could be switched to oral amoxicillin-clavulanate. The median duration of intravenously administered therapy for the 383 clinically evaluable patients was 4 days for both treatment groups; 345 patients (90.1%) had their treatment switched to orally administered therapy. Of the clinically evaluable patients, 168 (92.3%) in the ertapenem group and 183 (91.0%) in the ceftriaxone group had a favorable clinical response. Streptococcus pneumoniae was the most commonly isolated pathogen, and high cure rates were observed both for penicillin-susceptible and -nonsusceptible infections in the ertapenem group (28 [87.5%] of 32 patients versus 17 [100%] of 17 patients, respectively). Both treatment regimens were generally well tolerated; the most common drug-related adverse events reported were diarrhea (2.9% versus 2.7%) and nausea (0.8% versus 2.0%) in the ertapenem and ceftriaxone groups, respectively. These results suggest that ertapenem and ceftriaxone therapy have similar efficacy and safety in hospitalized patients with community-acquired pneumonia.