Extended-Spectrum -lactamases: Current situation, Diagnosis & ManagementSiriluck Anunnatsiri, MDInfectious Diseases & Tropical Medicine Faculty of MedicineKhon Kaen University

Extended-spectrum -lactamasesMutant, plasmid-mediated -lactamases enzymes derived from amino acid substitutions in native -lactamases, particularly TEM-1, TEM-2, and SHV-1Their ability permit hydrolyze all penicillins, cephalosporins (except cephamycins), and monobactamsTypically associated with multidrug resistance (fluoroquinolones, co-trimoxazole, aminoglycosides)

Extended-spectrum -lactamasesMost commonly produced by Klebsiella spp., Escherichia coli but can occur in other GNB, including Enterobacter, Salmonella, Proteus, and Citrobacter spp., Morganella morganii, Serratia marcescens, Shigella dysenteriae, Pseudomonas aeruginosa, and Burkholderia cepacia

Major groups of -lactamases Shah AA, et al. Research in Microbiology 2004; 155: 409-421.

Major groups of -lactamases Shah AA, et al. Research in Microbiology 2004; 155: 409-421.

Selected -lactamases of gram-negative bacteriaPeterson DL. Am J Med 2006; 119 (6 Suppl 1):S20-8.

Selected -lactamases of gram-negative bacteriaPeterson DL. Am J Med 2006; 119 (6 Suppl 1):S20-8.

Major sources of extended-spectrum -lactamases

Prevalence of ESBL-producing isolates in Europe (1997-2004) and USA (1999-2004) EuropeUSAGoossens H, Grabein B. Diagn Microbiol Infect Dis 2005; 53: 257-64.

Distribution of ESBL in E. coli SMART, 2003, IAI, Asia-Pacific Countries%

Distribution of ESBL in Klebsiella spp. SMART, 2003, IAI, Asia-Pacific Countries%

Prevalence of ESBL producing organisms 346 isolates of GNB, Siriraj Hospital, 2003Chayakulkeeree M, et al. Southeast Asian J Trop Med Public Health 2005; 36: 1503-9.

Prevalence of ESBL-producing organisms 2974 isolates of GNB, Srinagarind Hospital, 2005%

Risk factors associated with infection or colonization with ESBL-producing pathogensCritically ill patients / Severely debilitated residentsProlonged hospital or ICU unit stay Invasive procedures: indwelling catheter, central venous catheter,gastrostomy, tracheostomy, endotracheal or nasogastric tubeResidency in long-term care facilityDecubitus ulcerTotal dependence on health care workersPrior antibiotic use in last 3 monthsExposure to 2nd-3rd cephalosporins, aztreonam, penicillins, and quinolonesDelayed appropriate therapy

CLSI screening criteria for ESBLs in K. pneumoniae, K. oxytoca, and E.coli Strenburg E, Mark D. J Infect 2003; 47: 273-95.

Laboratory tests for ESBLs detection

Laboratory tests for ESBLs detection

Confirmatory tests for ESBL detectionStrenburg E, Mark D. J Infect 2003; 47: 273-95.

Multi-drug resistance in ESBL-producing organismsChayakulkeeree M, et al. Southeast Asian J Trop Med Public Health 2005; 36: 1503-9.

Resistance of ESBL-Producing E. coli and K. pneumoniae 1,182 Isolates, Srinagarind Hospital, Khon Kaen 2005%

Resistance of ESBL-Producing E. coli and K. pneumoniae 1,182 Isolates, Srinagarind Hospital, Khon Kaen 2005%

Inadequate antimicrobial treatment of infections: a risk factor for hospital mortality among critically ill patients Independent risk factors for hospital mortalityKollef MH et al. Chest 1999; 115: 462-74.

Retrospective study, 32/187 (17%) patients diedInadequate initial antimicrobial therapy (IIAT) was a risk factor for mortalityOR 10.04, 95% CI (1.90-52.96)Risk factors for IIAT Infection with multidrug-resistant ESBLs (14.58 [1.91-111.36]) Health care-acquired ESBLs infection (4.32 [1.49-12.54])

Arch Intern Med 2005;165:1375-80.

Outcome of cephalosporin treatment for serious infections due to apparently susceptible organisms producing ESBLPeterson et al. J Clin Microbiol 2001; 39: 2206-12.

Clinical implications of ESBL-producing Klebsiella species and Escherichia coli on cefepime effectivenessA retrospective, casecontrolled studyNone-urine source (~80% from lung) of 10 ESBL-cases & 20 controls (non-ESBL) treated with cefepime (2 grams/day, adjusted for GFR)Kotapati S, et al. J Infect 2005; 51: 211-7.

High-dose cefepime as an alternative treatment for infections caused by TEM-24 ESBL-producing Enterobacter aerogenes in severely-ill patientsRetrospective studySeriously-ill patients infected with ESBL-producing Enterobacter aerogenes, mostly TEM-2421 treated with cefepime (6 grams/day) / 23 treated with carbapenems (in combination with ciprofloxacin or amikacin)Cefepime Carbapenems P-valueClinical improvement62%70% 0.59Bacteriological eradication14%22% 0.7630-day mortality rate33%26% 0.44Nevertheless, a statistically significant increase in failure to eradicate ESBL-producing E. aerogenes was observed as the MICs of cefepime rose (p=0.017).

K. Goethaert et al. Clin Microbiol Infect 2006; 12: 56-62.

Cefepime versus Imipenem-Cilastatin for Treatment of Nosocomial Pneumonia in Intensive Care Unit Patients: a Multicenter, Evaluator-Blind, Prospective, Randomized StudyA randomized, evaluator-blind, multicenter triaCompared cefepime (6 g/day) vs. imipenem-cilastatin (2 g/day) for the treatment of nosocomial pneumonia in 281 intensive care unit patients.In subgroup analysis, therapy of pneumonia caused by an organism producing an extended spectrum-lactamase failed in 4 of 13 patients (31%) in the cefepime group but in none of 10 patients in the imipenem group.

Zanetti G, et al. Antimicrobe Agents Chemother 2003; 47: 3442-7.

Bacteremia due to Klebsiella pneumoniae isolates producing the TEM-52 extended-spectrum -lactamase: treatment outcome of patients receiving imipenem or ciprofloxacin Retrospective studyESBL (TEM-52) K. pneumoniae bacteremia, non-fatal disease10 treated with imipenem / 7 treated with ciprofloxacin Ciprofloxacin* Imipenem P-valueTreatment failure5/72/10 0.03* 2/7 = partial responseBecause the isolates had MICs of ciprofloxacin close to the susceptibility breakpoint, treatment failure could be ascribed to the inability of the drug to reach therapeutic concentrations at infected sites. Endimiani et al. Clin Infect Dis 2004; 38: 243-51.

A prospective, observational study12 centers, 455 episodes 18.7% with ESBL-K. pneumoniae

Pharmacodynamics of intermittent infusion piperacillin/tazobactam and cefepime against ESBL-producing organisms

Cefepime 1 gram q 12 hrs Pip/tazo 4.5 grams q 8 hrs Cefepime 1 gram q 8 hrs Pip/tazo 3.375 grams q 6 hrs Cefepime 2 gram q 12 hrs Pip/tazo 3.375 grams q 4 hrsReese AM, et al. Int J Antimicrobe Agents 2005; 26: 114-9.

Pharmacodynamics of continuous infusion piperacillin/tazobactam and cefepime against ESBL-producing organisms

Cefepime 3 grams Pip/tazo 6.75 grams Cefepime 4 grams Pip/tazo 13.5 grams Reese AM, et al. Int J Antimicrobe Agents 2005; 26: 114-9.

Pharmacodynamics of levofloxacin, gatifloxacin, and ciprofloxacin against ESBL-, and non-ESBL producing organismsMoczygemba LR, et al. Clin Ther 2004; 26: 1800-7.

Summary of 3rd-generation cephalosporins on treatment of ESBL-producing organismsClinical significance of inoculum effectPoor clinical outcomes are observed when 3rd-generation cephalosporins are used for treatmentHigher fatal outcomeHigher rate of clinical failure3rd-generation cephalosporins should not be used to treat serious infections with ESBL-producing organisms, even in the presence of apparent susceptibility.

Peterson et al. J Clin Microbiol 2001; 39: 2206-12.Ariffin H et al. Int J Infect Dis 2000; 4: 21-5.Wong-Beringer et al. Clin Infect Dis 2002; 34: 135-46.

Summary of 4th-generation cephalosporins on treatment of ESBL-producing organismsMore stable than 3rd-generation cephalosporins againt some ESBLs and very stable against AmpC-type -lactamasesInoculum effect, susceptible to SHV-typeNeed high dosage (> 4 grams/day) of cefepime for achieving the T>MIC target, preferably in combination with aminoglycoside for synergistic effectCefepime should not be used to treat serious infections with ESBL-producing organisms.

Summary of -lactam/-lactamase inhibitor on treatment of ESBL-producing organismsLimited clinical informationClass A ESBLs are susceptible to clavulanate and tazobactam in vitro, nevertheless many producers are resistant to -lactamase inhibitor due toHyperproduction of the ESBLs overwhelm inhibitorCo-production of inhibitor-resistant penicillinases (e.g. OXA-1) or AmpC enzymeRelative impermeability of the host strain-lactam/-lactamase inhibitor should not be used to treat serious infections with ESBL-producing organisms.

Summary of cephamycins on treatment of ESBL-producing organismsLimited clinical dataGenerally effective against Enterobacteriaceae producing TEM-, SHV-, and CTX-M-derived ESBLsCefotetan > cefoxitin : lower MICs Reports of cephamycins resistance development during prolonged therapyLoss of outer membrane porin (porin deficient mutant)Acquisition of plasmid-mediated AmpC -lactamase (ACT-1)

Summary of treatment recommendations for infections with ESBL producersLivermore DM, Peterson DL. ESBLs in resistance 2006.

Carbapenem classification

Dosage and Cost of Treatment in Patients with ESBL-producing bacteria Infections* 21 .. 2549Choice of Ertapenem can save cost of treatment about 1,265-2,435 Baht in patients with ESBL-producing bacteria infections.

Control of a Prolonged Outbreak of ESBL-Producing Enterobacteriaceae in a University Hospital

Imported ESBL-cases Acquired ESBL-cases Lucet JC, et al. Clin Infect Dis 1999; 29: 1411-8.

Class restriction of cephalosporin use to control total cephalosporin resistance in nosocomial Klebsiella* P < 0.01Rahal JJ, et al. JAMA 1998; 280: 1233-7.

OASIS I : Bowel Colonization with resistant GNB after antimicrobial therapy of IAIDiNubile MJ et al. Eur J Clin Microbiol Infect Dis 2005; 24: 443-9.

OASIS II : Bowel Colonization with resistant GNB after antimicrobial therapy of IAIDiNubile MJ et al. Eur J Clin Microbiol Infect Dis 2005; 24: 443-9.

OASIS I-II : Bowel Colonization with resistant GNB after antimicrobial therapy of IAIESBL-producing EnterobacteriaceaeDiNubile MJ et al. Eur J Clin Microbiol Infect Dis 2005; 24: 443-9.

OASIS I-II : Bowel Colonization with resistant GNB after antimicrobial therapy of IAIP. aeruginosa resistanceDiNubile MJ et al. Eur J Clin Microbiol Infect Dis 2005; 24: 443-9.

Summary of interventions that could be used to prevent problem with ESBL-producing bacteria in hospitalized patientsLivermore DM, Peterson DL. ESBLs in resistance 2006.

Take Home MessagesESBL-producing bacterial infection is an emerging problem worldwide.These organisms are associated with multi-drug resistance causing high rate of mortality and treatment failure.The significant risk factors for ESBL-producing bacterial infection are prior use of antibiotics, especially 3rd generation cephalosporins, and critically ill or debilitated patients.Need the ESBL-laboratory testing for establish the problem.Carbapenems is the drug of choice for serious ESBL-producing bacterial infection.Avoiding overuse or misuse of 3rd generation cephalosporins and implementing isolation and contact precaution to prevent and control the ESBL outbreak.

Cephamycins 7-methoxy side chain block hydrolyze class A & D beta-lactamases.Oxyimino-beta-lactams oxyimino side side chain beta-lactamases 3rd generation cephalosporins 4th generation cephalosporin Functional classification (Bush-Jacoby-Medeiros: 1-4) spectrum of ATB substrate profile, enzyme inhibitor profile, enzyme net charge, hydrolysis rate, binding affinity, isoelectric focusing, protein molecular weight, amino acid compositionMolecular classification (Amblers classification: A-D) nucleotide and amino acid sequenceFunctional classification (Bush-Jacoby-Medeiros: 1-4) spectrum of ATB substrate profile, enzyme inhibitor profile, enzyme net charge, hydrolysis rate, binding affinity, isoelectric focusing, protein molecular weight, amino acid compositionMolecular classification (Amblers classification: A-D) nucleotide and amino acid sequenceThe similar situation is also found in Klebsiella species.Normal interpretationSusceptibility zone for E.coli & Kleibsella: ceftazidime 18 mm, cefotaxime 23 mm, ceftriaxone 21 mm. combined disk test 3 ceftazidime, cefotaxime, ceftriaxone K. pneumoniae bacteremiaFailure to treat with active antibiotic during the 5-day period after positive blood culture was associated with higher mortality rate (63.6% vs 14.1%, p=0.001; OR 10.7 (95%CI 2.2-57))