Comparative evaluation of agar dilution and broth microdilution by commercial and in-house plates for Bacteroides fragilis group: An economical and expeditious approach for resource-limited settings.

OBJECTIVE: To compare the performance of agar dilution and broth microdilution by commercial and in-house prepared plates for the Bacteroides fragilis group. The cost analysis was performed to demonstrate that in-house prepared BMD plates were a suitable alternative to agar dilution given the high cost and low feasibility of incorporating commercial BMD plates in routine, particularly in the tertiary care institutes of many low- and middle-income countries. METHODS: Thirty B. fragilis group isolates were tested against six antibiotics, frequently used as empirical therapy for anaerobic infections including metronidazole, clindamycin, imipenem, piperacillin-tazobactam, cefoxitin, and chloramphenicol. The running consumable expenditure for all methodologies was calculated. RESULTS: The results demonstrated essential and categorical agreement of >90% for all antibiotics except cefoxitin, which showed <90% categorical agreement. No major or very major errors were observed. We observed a high agreement and strong concordance for MIC values between both methods and inter-rate reliability of >0.9 by Cohen's kappa analysis, indicating almost perfect agreement between both methods using either of the plates. In contrast to agar dilution, a 20.5 fold cost reduction was seen in BMD using in-house plates and a 5.8 fold reduction using commercial plates to test a single isolate. However, when testing 30 isolates concurrently the cost significantly increased for commercial BMD plates by 8.4 folds, and only 1.03 fold cost reduction was seen with in-house BMD plates. CONCLUSION: BMD gives comparable results to agar dilution and can be considered a method of choice to test a small number of samples. The technique is an economical option when plates are standardized in-house and could be employed for susceptibility testing of the B. fragilis group.

Effect of a "handshake" stewardship program versus a formulary restriction policy on High-End antibiotic use, expenditure, antibiotic resistance, and patient outcome.

This study reports the effect of implementing an antibiotic stewardship program (ASP) based on the "handshake" strategy for 2 years on multiple endpoints compared with that in a preceding period when an antimicrobial restriction policy was only applied in the absence of a complete program in a tertiary-care Lebanese hospital. The studied endpoints were broad-spectrum antibiotic consumption, antibiotic expenditure, nosocomial bacteremia incidence rate, and patient outcome.An interrupted time series analysis was undertaken to assess the changes in the trend (ΔT) and level (ΔL) of the aforementioned endpoints among adult inpatients before (October 2013 to September 2015) and after the introduction of the ASP (October 2016 to September 2018).After the implementation of the "handshake" ASP, marked changes were observed in the consumption of broad-spectrum antibiotics. The mean use density levels for imipenem and meropenem decreased by 13.72% (P = 0.017), coupled with a decreasing rate of prescription (ΔT = -24.83 defined daily dose [DDD]/1,000 patient days [PD]/month; P = 0.02). Tigecycline use significantly decreased in level by 69.19% (P < 0.0001) and in trend (ΔT = -25.63 DDD/1,000 PD/month; P < 0.0001). A reduction in the use of colistin was also documented but did not reach statistical significance (ΔL = -8.71%, P = 0.56; ΔT = -5.51 DDD/1,000 PD/month = -5.5; P = 0.67). Antibiotic costs decreased by 24.6% after ASP implementation (P < 0.0001), and there was a distinct change from an increasing rate to a decreasing rate of expenditure (ΔT = -12.19 US dollars/PD/month; P = 0.002). The incidence rate of nosocomial bacteremia caused by carbapenem-resistant gram-negative bacteria (CRGNB) decreased by 34.84% (P = 0.13) coupled with a decreasing trend (ΔT = -0.23 cases/1,000 PD/month, P = 0.08). Specifically, a noticeable reduction in the incidence rate of bacteremia due to carbapenem-resistant Acinetobacter baumannii was documented (ΔL = -54.34%, P = 0.01; ΔT = -0.24 cases/1000 PD/month, P = 0.01). Regarding patient outcome, all-cause mortality rates did not increase in level or in rate (ΔL = -3.55%, P = 0.59; ΔT = -0.29 deaths/1000 PD/month, P = 0.6). The length of stay and 7-day readmission rate remained stable between the two periods.In conclusion, the "handshake" ASP succeeded in controlling the prescription rates of antibiotics and in decreasing the nosocomial bacteremia rates caused by CRGNB without compromising patient outcome in our facility. It also had an economic effect in reducing antibiotic costs compared with the previous restriction policy on antimicrobial dispensing.

Cost-effectiveness analysis of ceftazidime/avibactam compared to imipenem as empirical treatment for complicated urinary tract infections.

Ceftazidime/avibactam (CAZ-AVI) is a novel, fixed-dose combination antibiotic that has been approved in Europe and the United States for patients with complicated urinary tract infections (cUTIs) based on results of a Phase III, randomized, comparative study (RECAPTURE study). The present analysis evaluated cost-effectiveness of CAZ-AVI as an empirical treatment for hospitalized patients with cUTIs from the Italian publicly funded healthcare (third-party payer) perspective. A sequential, patient-level simulation model was developed that followed the clinical course of cUTI and generated 5000 pairs of identical patients (CAZ-AVI or imipenem as empirical treatment). The model included additional impact of resistant pathogens; patients who did not respond to empirical treatment were switched to second-line treatment of colistin+high dose carbapenem in both groups. The time horizon of the model was five years, with an annual discount rate of 3% applied to both costs and quality-adjusted life-years (QALYs). The analysis demonstrated that an intervention sequence (CAZ-AVI followed by colistin+high dose carbapenem) compared with a comparator sequence (imipenem followed by colistin+high dose carbapenem) was associated with a net incremental cost of €1015 per patient but provided better health outcomes in terms of clinical cure (97.65% vs. 91.08%; ∆ = 6.57%), shorter hospital stays (10.65 vs. 12.55 days; ∆ = 1.90 days), and QALYs gained per patient (4.190 vs. 4.063; ∆ = 0.126). The incremental cost-effectiveness ratio was €8039/QALY, which is well below the willingness-to-pay threshold of €30 000/QALY in Italy. The results showed that CAZ-AVI is expected to be a cost-effective treatment compared with imipenem for cUTI in Italy.

The impact of a nationwide antibiotic restriction program on antibiotic usage and resistance against nosocomial pathogens in Turkey.

PURPOSE: Antimicrobial resistance among microorganisms is a global concern. In 2003, a nationwide antibiotic restriction program (NARP) was released in Turkey. In this study we evaluated the effect of NARP on antibiotic consumption, antimicrobial resistance, and cost. MATERIALS AND METHODS: The data obtained from all of the four university hospitals, and one referral tertiary-care educational state hospital in Ankara. Antimicrobial resistance profiles of 14,233 selected microorganisms all grown in blood cultures and antibiotic consumption from 2001 to 2005 were analyzed retrospectively. RESULTS: A negative correlation was observed between the ceftriaxone consumption and the prevalence of ceftriaxone resistant E.coli and Klebsiella spp. (rho:-0.395, p:0.332 and rho:-0.627, p:0.037, respectively). The decreased usage of carbapenems was correlated with decreased carbapenems-resistant Pseudomonas spp. and Acinetobacter spp (rho:0.155, p:0.712 and rho:0.180, p:0.668, respectively for imipenem). Methicillin resistance rates of S.aureus were decreased from 44% to 41%. After two years of NARP 5,389,155.82 USD saving occurred. CONCLUSION: NARP is effective in lowering the costs and antibiotic resistance.

Cost-effectiveness model of empiric doripenem compared with imipenem-cilastatin in ventilator-associated pneumonia.

BACKGROUND: Ventilator-associated pneumonia (VAP) is a common complication of critical illness among surgical and trauma patients. Inappropriate empiric treatment of VAP increases the mortality rate. The rates of Pseudomonas aeruginosa (PA) VAP susceptibility to doripenem (DOR) are higher than those to imipenem-cilastatin (IMI). We developed a model to quantify outcome differences between strategies of empiric treatment of VAP with DOR vs. IMI. METHODS: We designed a cost-effectiveness model comparing empiric treatment of VAP with DOR vs. IMI from both the hospital and societal perspectives. We examined the differences in the number of deaths, hospital length of stay (LOS), total costs, and quality-adjusted life years (QALY) under each scenario and conducted Monte Carlo simulations and sensitivity analyses to determine the stability of our estimates. Drug costs were taken as 80% of wholesale acquisition costs, with other inputs derived from the literature. RESULTS: In the base case analysis, assuming a PA-VAP attributable mortality rate of 38.4% and a 49% relative risk reduction in deaths in PA-sensitive (PA-S) infections to empiric drug compared with a resistant PA (PA-R) organism, DOR use resulted in three additional deaths avoided, 117.4 days of hospitalization averted, and hospital savings of $422,524 per 1,000 patients treated at a cost of $5,748/QALY. All estimates were most sensitive to the costs of treating PA-S and PA-R infections. In a multivariable analysis, hospital cost savings persisted across >80% of the simulations (95% confidence interval $432,615-$2,148,540). CONCLUSIONS: Given the current microbiologic sensitivity profile of PA to DOR and IMI, and depending on the local susceptibility patterns and in institutions where DOR in vitro susceptibilities are superior to those of other carbapenems for PA clinical isolates, empiric treatment of VAP with DOR may dominate that with IMI by being both life- and cost-saving.

Economic assessment of doripenem versus imipenem in the treatment of ventilator-associated pneumonia.

BACKGROUND: Ventilator-associated pneumonia (VAP), the most common nosocomial infection in critically ill patients, is associated with significantly longer duration of mechanical ventilation, and increased mortality, hospital days, and health-care costs. A previously published prospective, randomized study established the noninferiority of intravenous (IV) doripenem versus IV imipenem/cilastatin ('imipenem') for VAP. This study compares the economic outcomes of IV therapy with doripenem versus imipenem as first-line treatment for VAP. METHODS: A decision-analytic model of inpatient care and outcomes for VAP was used to estimate costs associated with VAP treatment. The model calculates total hospital costs, comprising costs of initial and concomitant therapy, and costs associated with mechanical ventilation, intensive care unit stays, and total days in hospital. RESULTS: Total treatment costs for doripenem were $10,630 lower than for imipenem ($71,259 vs. 81,889), driven primarily by differences in costs of mechanical ventilation ($45,224 for doripenem, $57,348 for imipenem). Probabilistic sensitivity analyses found doripenem consistently cost saving versus imipenem in 1,000 simulations. Study limitations include use of a simple model to represent a complex disease process and reliance on trial data that may not reflect real-world care and outcomes. CONCLUSIONS: Doripenem is a cost saving first-line treatment for VAP versus imipenem while providing an equivalent rate of cure.

Management and prevention of diabetic foot ulcers and infections: a health economic review.

Diabetic foot ulcers and infections are common and incur substantial economic burden for society, patients and families. We performed a comprehensive review, on a number of databases, of health economic evaluations of a variety of different prevention, diagnostic and treatment strategies in the area of diabetic foot ulcers and infections. We included English-language, peer-reviewed, cost-effectiveness, cost-minimization, cost-utility and cost-benefit studies that evaluated a treatment modality against placebo or comparator (i.e. drug, standard of care), regardless of year. Differences were settled through consensus. The search resulted in 1885 potential citations, of which 20 studies were retained for analysis (3 cost minimization, 13 cost effectiveness and 4 cost utility). Quality scores of studies ranged from 70.8% (fair) to 87.5% (good); mean = 78.4% +/- 5.33%.In diagnosing osteomyelitis in patients with diabetic foot infection, magnetic resonance imaging (MRI) showed 82% sensitivity and 80% specificity. MRI cost less than 3-phase bone scanning + Indium (In)-111/Gallium (Ga)-67; however, when compared with prolonged antibacterials, MRI cost $US120 (year 1993 value) more without additional quality-adjusted life-expectancy. Prevention strategies improved life expectancy and QALYs and reduced foot ulcer rates and amputations.Ampicillin/sulbactam and imipenem/cilastatin were both 80% successful in treating diabetic foot infections but the latter cost $US2924 more (year 1994 value). Linezolid cure rates were higher (97.7%) than vancomycin (86.0%) and cost $US873 less (year 2004 value). Ertapenem costs were significantly lower than piperacillin/tazobactam ($US356 vs $US503, respectively; year 2005 values). Becaplermin plus good wound care may be cost effective in specific populations. Bioengineered living-skin equivalents increased ulcer-free months and ulcers healed, but costs varied between countries. Promogran produced more ulcer-free months than wound care alone (3.75 vs 3.41 months, respectively). Treatment with cadexomer iodine resulted in higher rates of healed ulcer (29% vs 11%) and lower weekly treatment costs (Swedish krona [SEK]903 vs SEK1421; year 1993 values) than standard care. Filgrastim decreased hospital stays, time to resolution and costs (36% lower) compared with usual care. Adjunctive hyperbaric oxygen produced an incremental cost per QALY at year 1 of $US27 310 and $US2255 at year 12 (year 2001 values).Overall, preventive strategies were shown to be cost effective and potentially cost saving. Various antibacterial regimens are cost effective but empiric choices should be based on local resistance patterns. MRI was cost effective compared with three-phase bone scanning + In-111/Ga-67 but not against prolonged antibacterial therapy. Other innovations (becaplermin, bioengineered living-skin equivalents, filgrastim, cadexomer iodine ointment, hyperbaric oxygen, Promogran may be cost effective in this population but more studies are needed to confirm these findings.

Hospital resource utilization with doripenem versus imipenem in the treatment of ventilator-associated pneumonia.

BACKGROUND: Ventilator-associated pneumonia (VAP) is a common nosocomial infection that is associated with prolonged length of stay (LOS) and significant mortality. OBJECTIVE: The aim of this study was to compare resource utilization with doripenem, an investigational carbapenem, versus imipenem from a hospital perspective among patients with VAP. METHODS: This analysis was based on data from a Phase III, randomized, open-label, noninferiority study that compared clinical cure of VAP with doripenem 500 mg q8h i.v. (4-hour infusion) with imipenem 500 mg q6h (30-minute infusion) or 1000 mg q8h i.v. (1-hour infusion). Total hospital LOS, intensive care unit (ICU) LOS, and time on mechanical ventilation for doripenem and imipenem were compared in a clinical modified intent-to-treat population. P values were determined using the generalized Wilcoxon test, which compared treatments in a time-to-event analysis, censoring patients at the late follow-up visit (28-35 days after the end of i.v. therapy). RESULTS: Patients in the doripenem and imipenem groups had similar baseline clinical characteristics. Median hospital LOS was significantly shorter with doripenem versus imipenem (22 vs 27 days; P=0.010); median time on mechanical ventilation was significantly shorter for doripenem (7 vs 10 days; P=0.034); median ICU LOSs were similar between the 2 groups (12 vs 13 days). Clinical cure and mortality rates were similar. CONCLUSIONS: Of the 3 primary end points in this analysis, hospital LOS and time on mechanical ventilation were significantly shorter with doripenem compared with imipenem; no statistical significance was observed in ICU LOS. These findings suggest that doripenem use may be associated with an economic and clinical benefit to patients and hospitals.

Ertapenem susceptibility of extended spectrum beta-lactamase-producing organisms.

BACKGROUND: Infections caused by multiply drug resistant organisms such as extended spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae are increasing. Carbapenems (imipenem and meropenem) are the antibiotics commonly used to treat these agents. There is limited clinical data regarding the efficacy of the newest carbapenem, ertapenem, against these organisms. Ertapenem susceptibility of ESBL-producing E. coli and K. pneumoniae clinical isolates were evaluated and compared to imipenem to determine if imipenem susceptibility could be used as a surrogate for ertapenem susceptibility. METHODS: 100 ESBL isolates (n = 34 E. coli and n = 66 K. pneumoniae) collected from 2005-2006 clinical specimens at WRAMC were identified and tested for susceptibility by Vitek Legacy [bioMerieux, Durham, NC]. Ertapenem susceptibility was performed via epsilometer test (E-test) [AB Biodisk, Solna, Sweden]. RESULTS: 100% of ESBL isolates tested were susceptible to ertapenem. 100% of the same isolates were also susceptible to imipenem. CONCLUSION: These results, based on 100% susceptibility, suggest that ertapenem may be an alternative to other carbapenems for the treatment of infections caused by ESBL-producing E. coli and K. pneumoniae. Clinical outcomes studies are needed to determine if ertapenem is effective for the treatment of infection caused by these organisms. However, due to lack of resistant isolates, we are unable to conclude whether imipenem susceptibility accurately predicts ertapenem susceptibility.

Predictors of efficacy and health resource utilization in treatment of complicated intra-abdominal infections: evidence for pooled clinical studies comparing tigecycline with imipenem-cilastatin.

BACKGROUND: Duration of intravenous (IV) treatment, surgical/radiologic interventions for infection control, and hospital length of stay (LOS) are important cost considerations in complicated intra-abdominal infections (cIAIs). METHODS: Data were pooled from two multinational, double-blind studies conducted in hospitalized adults with cIAIs who were randomized (1:1) to receive tigecycline (100 mg IV initial dose then 50 mg IV every 12 h) or imipenem-cilastatin (500 mg IV every 6 h) for 5 to 14 days in order to assess tigecycline safety and efficacy. This report focuses on developing predictors of cure and health care resource utilization, including the need for repeat surgical/radiologic interventions, duration of IV antibiotic therapy, and hospital LOS. Multiple regression models were applied for each of the above outcomes, incorporating both baseline and on-treatment potential covariates. Logistic modeling was used for categorical outcomes (cure; repeat surgical/radiologic interventions) and least squares modeling for continuous outcomes (duration of IV antibiotic therapy; LOS). Stepwise selection was used to retain only those predictors found to be significant (p < 0.05) independent risk factors. RESULTS: The most common causative pathogen was Escherichia coli (63.0%), with 63.3% of the patients exhibiting polymicrobial infections. The most common cIAI diagnosis was complicated appendicitis (51.9%). Lack of clinical cure (+ 6.1 days; p < 0.0001), perforation of the intestine (+3.7 days; p < 0.0001), an Acute Physiology and Chronic Health Evaluation (APACHE) score >15 (+3.1 days; p=0.039), abnormal plasma sodium concentration (+3.7 days; p=0.026), and repeat surgical/radiologic intervention (+2.2 days; p=0.0097) were identified as key risk factors for longer LOS. Inadequate source control was associated with reduced odds of cure, longer IV treatment duration (+1.5 days; p=0.007), and longer LOS. The treatment groups did not differ in terms of LOS, IV treatment duration, or clinical cure. CONCLUSION: Tigecycline was similar to imipenem-cilastatin in terms of both efficacy and health resource utilization. Risk factors identified in this study for both outcome measures are offered as support for guiding clinical practice.

Imipenem/cilastatin versus piperacillin/tazobactam plus amikacin for empirical therapy in febrile neutropenic patients: results of the COSTINE study.

BACKGROUND: Combinations of beta-lactams plus aminoglycosides have become standard therapy for suspected infections in patients with profound neutropenia. However, it is not clear whether such combinations are advantageous over therapy with a broad-spectrum antibiotic. OBJECTIVE: To assess the clinical effectiveness and the cost-effectiveness ratio of empirical therapy of febrile neutropenia with imipenem/cilastatin (I/C) versus piperacillin/tazobactam plus amikacin (P/T+A). RESEARCH DESIGN AND METHODS: Prospective, multicenter observational study with 2 matched parallel cohorts treated with I/C (500 mg/6 h iv) or P/T+A (P/T: 4 g/6 h iv; A: 20 mg/kg/day iv). MAIN OUTCOME MEASURES: Therapeutic success was defined as the resolution of fever following > or = 7 days of unchanged antibiotic treatment. An economic comparison was conducted focusing on the daily treatment costs, and the management of its toxicity. RESULTS: There were 343 eligible patients (180 I/C, 163 P/T+A), of whom 290 were evaluable for the primary clinical effectiveness analysis. Follow-up information beyond 7 days of study inclusion was only available for 52% of all evaluable patients. Treatment success was observed in 42% of I/C patients compared with 31% of P/T+A patients (95% CI: -0.01, 21.4). The incidence of drug-related adverse experiences was 13% for I/C and 6% for P/T+A, with no differences in moderate or severe adverse experiences nor in those causing discontinuation of antibiotic therapy. Treatment costs were 189.55 euros (95% CI: 127.46-251.46) lower per episode of febrile neutropenia for patients treated with I/C. CONCLUSIONS: The clinical effectiveness of I/C was similar to that of P/T+A. In both treatment groups toxicity was low and did not limit antibiotic therapy. Resource consumption was lower with I/C.

The cost-effectiveness of cefepime plus metronidazole versus imipenem/cilastatin in the treatment of complicated intra-abdominal infection.

BACKGROUND: Our objective was to compare the economic benefits of cefepime plus metronidazole with those of imipenem/cilastatin in the treatment of complicated intra-abdominal infections. METHODS: We used a retrospective analysis of clinical outcomes and health resource utilization data collected during a randomized, double-blind, multi-center clinical trial. Seventeen university-affiliated hospitals in the United States and Canada participated, as did 323 patients with complicated intra-abdominal infections. Decision analysis was conducted using a decision node of cefepime vs. imipenem, and chance nodes that included an Acute Physiology and Chronic Health Evaluation (APACHE) II score of #15 versus .15; a need for posttreatment surgical procedures; and clinical outcomes. Effectiveness of treatment was measured by differences in the length and cost of hospital stays, the number and cost of surgical procedures after treatment, cure rates, and the cost of antibiotics. Also evalulated were the incremental costs of cure (i.e., the costs of additional cures). RESULTS: Comparing cefepime plus metronidazole with imipenem/cilastatin, the expected cost of patient care was $8,218 versus $10,414, respectively, and the cost-effectiveness ratio per cure was $10,058 versus $13,685. For severely ill patients (APACHE II score .15), the expected cost was $12,962 versus $23,153, and the cost-effectiveness ratio per cure was $15,321 versus $64,313. CONCLUSIONS: Cefepime plus metronidazole was more cost-effective than imipenem/cilastatin in the treatment of complicated intra-abdominal infections, primarily because of fewer post-treatment surgical procedures and shorter hospital stays. The primary advantage accrued to severely ill patients who had an APACHE II score .15.

[Comparative clinical and epidemiological evaluation of beta-lactam antibiotics in the treatment of intraabdominal infections]. / Sravnitel'naia kliniko-ékonomicheskaia otsenka betalaktamnykh antibiotikov pri lechenii intraabdominal'nykh infektsii.

We performed a retrospective, comparative study to evaluate efficacy, safety and economic outcomes of empiric cefoperazone/sulbactam monotherapy compared with the meropenem, imipenem/cilastatine and combination of cefepime plus metroindazol in patients with intra-abdominal infection. A total of 468 patients diagnosed with intra-abdominal abscess, peritonitis, pancreatitis were included in the study (the severity of infection according to scale APACHE II was less than 15). Patients were randomized to be treated with either 500 mg meropemen i.v. every 8 hours or 500 mg imipenem/cilastatine i.v. every 8 hours or 2 g cefepime i.v. every 12 hours plus 500 mg metronidazol twice daily or cefoperazone/sulbactam 2 g daily administered every 12 hours. Overall positive clinical responses (cure or improvement) were achieved at the end of treatment for 87.5 patients in meropenem group, 86.6% in the imipenem/cilastatin group, 85.3% in the cefepime group and 86.8% in cefoperazone/sulbactam group. Total cost of the treatment per 100 patients with intra-abdominal infections for cefoperazone/sulbactam was 1957031 roubles, for combinations of cefepime with metronidazol--2497815 roubles. For carbapenem group cost achieved for meropenem--3085291 rub., for imipenem/cilastatin--2653388 roubles. Rate "cost-effectiveness" in total: 784.47$ for cefepime, and 834.39$ for imipenem/cilastatine, 970.21$ for meropenem and 615.4$ for cefoperazone/sulbactam. The most expensive treatment was considered to be with meropenem and imipenem/cilastatine, main share is determined by initial cost of preparations. Less expensive was treatment by cefoperazone/sulbactam with cefepime and by metronidazol.

Attributable costs and length of stay of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae outbreak in a neonatal intensive care unit.

OBJECTIVES: To determine the costs of the interventions aimed at controlling the 4-month outbreak and to determine the attributable length of stay (LOS) associated with infection and colonization with extended-spectrum beta-lactamase-producing Klebsiella pneumoniae. DESIGN: A retrospective cost analysis was conducted from the hospital perspective. A micro-costing approach was employed. The LOS of four groups of hospitalized patients were compared with each other. National Perinatal Information Center criteria were used to stratify infants for severity of risk. The LOS of each group was compared with that of a national sample of similarly stratified infants. SETTING: A level III-IV, 45-bed neonatal intensive care unit. PATIENTS: Infant groups were infected (n = 8), colonized (n = 14), concurrent cohort (n = 54), and prior cohort (n = 486). RESULTS: The cost of the outbreak totaled 341,751 dollars. The largest proportion of costs was related to healthcare worker time providing direct patient care (2,489 hours at a cost of 146,331 dollars). Infected and colonized neonates had longer LOS than either the concurrent cohort or the prior cohort (P < .001). Compared with the national sample, infected infants had a 48.5-day longer mean LOS (95% confidence interval [CI95], 1.7 to 95.2), whereas the prior cohort's mean LOS was 6 days shorter (CI95, -9.4 to -2.9). CONCLUSIONS: This study increases the understanding of the burden of these multidrug-resistant organisms. Further research is needed to estimate the societal costs of these infections and the cost-effectiveness of preventive interventions.

Treatment of secondary peritonitis: is a less expensive broad-spectrum antibiotic as effective as a carbapenem?

BACKGROUND: In this retrospective study, the possibility of using amoxicillin/clavulanate for empirical therapy of secondary peritonitis as an alternative to imipenem was explored. METHODS: All secondary peritonitis cases at our institution between 1998 and 2000 were included. Susceptibility to imipenem and amoxicillin/clavulanate of microorganisms isolated in peritoneal fluid and success rates were compared. Therapeutic failure was defined as death, necessity of repeated surgical intervention, or clinical deterioration with persistent positive cultures. RESULTS: Seventy-six cases of secondary peritonitis with 156 microorganisms were found. One hundred and forty-nine (98%) were susceptible to imipenem versus 124 (82%) to amoxicillin/clavulanate (p = 0.0001). Thirteen therapeutic failures occurred in 52 patients treated with amoxicillin/clavulanate (25%) versus 3 out of 8 (38%) with imipenem (p = 0.43). The proportion of organisms resistant to amoxicillin/clavulanate in therapeutic failures was greater in nosocomial versus community-acquired secondary peritonitis (p = 0.041). CONCLUSION: Despite its better in vitro bacteriological activity, clinical efficacy of imipenem was identical to amoxicillin/clavulanate. The use of amoxicillin/clavulanate instead of imipenem would save 889 Euro per case.

Empiric carbapenem monotherapy in pediatric bone marrow transplant recipients.

OBJECTIVE: To determine which carbapenem (imipenem/cilastatin or meropenem) was the preferable empiric antibiotic monotherapy in pre-engrafted pediatric bone marrow transplant (BMT) patients in terms of patient tolerance, therapeutic efficacy, and cost. METHODS: We prospectively analyzed 16 pediatric BMT patients who received meropenem, and retrospectively analyzed 16 matched patients who had received imipenem/cilastatin for BMT procedures during the prior 2-year period. We evaluated the patients for evidence of bacterial infection, necessity for concurrent antibiotics, vomiting episodes, duration of concurrent total parenteral nutrition (TPN), and cost of therapy. RESULTS: We found no differences in the number of culture proven or clinically suspected breakthrough bacterial infections or the need for concurrent additional antibiotics between the groups. Our analysis found that patients who received meropenem experienced significantly less vomiting than those in the imipenem/cilastatin cohort. Our data showed both direct and indirect cost savings for the meropenem group. The statistical and clinical differences in the number of vomiting episodes between these groups impacted other aspects of patient care, antiemetic use, and TPN duration. CONCLUSIONS: By switching to meropenem, we reduced the cost of antiemetic therapy per patient treatment course, and also showed a trend toward reduced duration of TPN. We found that meropenem provided both clinical and fiscal advantages over imipenem/cilastatin as empiric antibiotic monotherapy in neutropenic pediatric BMT patients.

Carbapenems in the treatment of severe community-acquired pneumonia in hospitalized elderly patients: a comparative study against standard therapy.

In this open, prospective, study were enrolled 204 hospitalized elderly patients with severe (88 males, 116 females, age range 70-94). Patients were randomized to receive one of the following antibiotic treatment regimens: meropenem 500 mg i.v. t.i.d. (52); imipenem/cilastatin 500 mg i.v. t.i.d. (51), clarithromycin 500 mg + ceftriaxone 1 g i.v. b.i.d. (52), clarithromycin 500 mg + amikacin 250 mg i.v. b.i.d. (49). In 99 cases causative germs were isolated (24 meropenem, 26 imipenem, 23 clarithromycin + ceftriaxone, 26 ceftriaxone + amikacin). A satisfactory clinical, bacteriological response was achieved respectively in 86.5% 77% in meropenem; 86.3% 71% in imipenem/cilastatin; 69% 61% in ceftriaxone + clarithromycin and in 85.7% 77% in clarithromycin + amikacin. The mean total cost for each patient was $1,560; $1,620; $1,760 and $1,792 in meropenem, imipenem/cilastatin, clarithromycin + ceftriaxone and clarithromycin + amikacin respectively. This study shows that treatment with either meropenem or imipenem is as efficacious as conventional therapy in the treatment of community acquired pneumonia (CAP), and that meropenem is the most cost-effective.

Cost efficacy of tazobactam/piperacillin versus imipenem/cilastatin in the treatment of intra-abdominal infection.

OBJECTIVE: To compare the cost, efficacy and cost efficacy of tazobactam/piperacillin and imipenem/cilastatin in the treatment of intra-abdominal infection. DESIGN: The analysis was retrospective and based on a decision tree. Effectiveness data were obtained from 19 published clinical trials. Direct costs were quantified per patient from the time the decision was made to administer the antibacterial to the end of the first course of treatment or the end of a subsequent course of treatment, if required. The primary end-point was the cost per successfully treated patient. The cost per life saved was also analysed. Various follow-up times were taken into account. PERSPECTIVE: German National Health Insurance funds. STUDY POPULATION: 1744 patients with intra-abdominal infection. INTERVENTIONS: Tazobactam/piperacillin (total daily dosage of 13.5 g/day) and imipenem/cilastatin (total daily dosage of 1.5 to 4 g/day). The mean duration of treatment varied from 5.5 to 8.2 days for tazobactam/piperacillin and 5 to 9.4 days for imipenem/cilastatin. MAIN OUTCOME MEASURE AND RESULTS: Compared with imipenem/cilastatin, treatment with tazobactam/piperacillin was more effective and the overall treatment costs were lower. In the base-case analysis, the cost-efficacy ratio (cost per successfully treated patient) was 7881 German deutschmarks (DM) for tazobactam/piperacillin and DM11,390 for imipenem/cilastatin. The incremental cost-efficacy ratio (per life saved) varied between -DM72,567 and -DM350,738 for tazobactam/piperacillin. Sensitivity analyses revealed that the results were robust against various assumptions on cost parameters, clinical outcomes and length of treatment. All costs reflect 1998 values; $US1 = DM1.85. CONCLUSIONS: This study suggests that compared with imipenem/cilastatin, tazobactam/piperacillin is more cost efficacious in the treatment of intra-abdominal infections and that it offers a cost advantage through fewer relapses and lower daily therapeutic costs.

Epidemiology, resistance, and outcomes of Acinetobacter baumannii bacteremia treated with imipenem-cilastatin or ampicillin-sulbactam.

STUDY OBJECTIVE: To evaluate epidemiology, resistance, and treatment outcomes of Acinetobacter baumannii bacteremia treated with imipenem-cilastatin or ampicillin-sulbactam for 72 hours or longer. DESIGN: Retrospective analysis. SETTING: University teaching hospital. PATIENTS: Forty-eight patients with A. baumannii bacteremia. INTERVENTION: Evaluation of susceptibility and clinical data from 48 patients treated with either ampicillin-sulbactam or imipenem-cilastatin from 1987-1999. MEASUREMENTS AND MAIN RESULTS: Comparing ampicillin-sulbactam and imipenem-cilastatin, there were no differences between days of bacteremia (4 vs 2 days, p=0.05), days to resolution of temperature or white blood cell count, success or failure during or at end of treatment, or intensive care unit total or antibiotic-related length of stay (13 vs 10 days, p=0.05). Patients treated with ampicillin-sulbactam had significantly decreased antibiotic treatment costs (1500 dollars vs 500 dollars, p=0.004). CONCLUSION: Ampicillin-sulbactam is at least as effective as imipenem-cilastatin based on clinical response at days 2, 7, and end of treatment and is a cost-effective alternative for treatment of A. baumannii infections.

Cost-effectiveness study of imipenem/cilastatin versus meropenem in intra-abdominal infections.

BACKGROUND: The efficacy of two carbapenems, imipenem/cilastatin (I/C, 1.5 g daily) versus meropenem (3 g daily) in intra-abdominal infections was assessed in a recent multicenter randomized clinical trial. The aim of this article is to perform a cost-effectiveness analysis as in real-world practice according to the findings of this clinical trial. METHODS: A decision tree was used to estimate the clinical outcomes and direct costs of treating intra-abdominal infections using the two carbapenems from the perspective of the Italian National Health Service (INHS) or a private insurance company (PIC). RESULTS: In a population of 30,000 patients with intra-abdominal infections in Italy, it was estimated that 97 potential deaths/year could be avoided if these patients were treated with I/C versus meropenem. In addition, from the perspective of INHS, the total costs of treatment were estimated as ITL 106,874 million and 134,042 million for I/C and meropenem, respectively. In favor of the PIC point of view, the total costs were estimated as ITL 110,500 million and 135,899 million for I/C and meropenem, respectively. CONCLUSION: The treatment of intra-abdominal infections with I/C is shown to be more effective (97 deaths avoided/year) and less costly than with meropenem (with a saving of ITL 27,168 and 25,399 million/year for INHS and PIC, respectively).