1 / 77

Antibiotic Resistant Infections: Focus on MRSA and ESBL George G. Zhanel Microbiologist

A Patient With a Multi-Drug Resistant (MDR) Urinary Infection. 78y M with prostatic hypertrophy and urinary infection symptomsAlready taking ciprofloxacin without any benefit x 10 daysRecent travel to India, no prior history of urinary infectionUrine culture from one week ago grew

alicia
Download Presentation

Antibiotic Resistant Infections: Focus on MRSA and ESBL George G. Zhanel Microbiologist

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


    2. A Patient With a Multi-Drug Resistant (MDR) Urinary Infection 78y M with prostatic hypertrophy and urinary infection symptoms Already taking ciprofloxacin without any benefit x 10 days Recent travel to India, no prior history of urinary infection Urine culture from one week ago grew E. coli Pelvic, rectal and kidney ultrasound normal

    3. This MDR E. coli is a Superbug! Ampicillin ...R TMP/SMX .....R Ciprofloxacin .....R Gentamicin ...R Tobramycin ...R Amikacin ...R Cefazolin ...R Cefuroxime ...R Cefotaxime ...R Ceftazidime ...R Meropenem ...S

    4. How Should We Treat This Patient ? Amoxicillin-Clavulanate 500mg/125mg po TID and his symptoms resolve in 4 days Repeat cultures at 8 weeks were negative We got lucky !!!

    5. Antibiotic Resistant Superbugs

    6. Leading Infectious Diseases Killers (World Health Organization-1998)

    7. History of Antibiotic Resistant Superbugs 1928 Fleming discovers penicillin 1946 Penicillin resistant Staphylococci 1969 US Surgeon General Its time to close the book on Infectious Diseases 2010 Superbugs winning the race

    8. Greater morbidity and mortality Hospitalization and supportive care Increased use of: Laboratory and diagnostic tests Infection control procedures More expensive antimicrobials Length of hospital stay and lost work days

    9. Few New Antimicrobials on the Horizon

    10. 10 Antibiotic Resistant Pathogens are Spreading Across the World

    11. CANWARD 2007-9 George G. Zhanel, Mel DeCorby, Nancy Laing, Barb Weshnoweski, Ravi Vashisht, Kim Nichol, Patricia Baudry, Aleksandra Wierzbowski, James Karlowsky, Franil Tailor, Andrew Walkty, Philippe Lagac-Wiens, Jack Johnson, Melissa McCracken, Michael Mulvey, The Canadian Antimicrobial Resistance Alliance (CARA) and Daryl J. Hoban University of Manitoba, Health Sciences Centre, National Microbiology Lab, Winnipeg, Canada and International Health Management Associates (IHMA), Chicago, USA

    12. Most Common Pathogens Hospitals (CANWARD 2008; n=5282)

    13. Staphylococcus aureus Leads to a wide range of infections Virulence factors: skin and soft tissue, food poisoning, pneumonia, bacteremia Toxin mediated: Food poisoning, TSS, skin and soft tissue infections, necrotizing pneumonia

    14. History of Methicillin Resistant Staphylococcus aureus (MRSA) Before penicillin S.aureus bacteremia had a very high mortality 1940s penicillin introduced 1946 PRSA 1960 methicillin introduced late 1960s MRSA 1970s - 1990s MRSA increases globally 1970s 1990s vancomycin last effective treatment 1996 Japan first report of VISA 1999 reports of CA-MRSA 2002-present 9 isolates of VRSA

    16. Antibiotic Resistance of MRSA in Canadian ICUs (CAN-ICU n=197 or 4.7%)

    17. S. aureus Bacteremia: Hospital Costs

    18. HA- and CA-MRSA Infection: Epidemiology

    19. Community-associated MRSA CA-MRSA may cause severe, life-threatening soft tissue infections in healthy adults

    21. Community-associated MRSA Injection drug addicts Homeless shelters Nursing homes

    22. Community-associated MRSA Epidemic outbreaks in: Day-care centers Prison inmates Ships; military Contact sports

    23. Community-associated MRSA Epidemic of skin/soft tissue infections St. Louis Rams (2003)

    24. CA-MRSA: NFL Football Team MRSA infections 5 of 58 players (9%) Identical strain

    25. CA-MRSA: NFL Football Team Risk factor Lineman or linebacker: 10.6 Antibiotics within 12 mos: 7.8

    26. CA-MRSA: NFL Football Team Transmission of MRSA During 2003 season, outbreak of abscesses in competing team after game with Rams

    29. CA-MRSA National (n=16) CAN-ICU

    30. Mechanisms of Resistance in MRSA Five PBPs (1,2,3,3,4) new PBP 2a, low affinity PBP PBP 2a does not efficiently bind beta-lactams resistance determinant: mecA carried on a mobile element called SCCmec foreign DNA chromosomal mecA expression affected by ph, temp, NaCl, osm, mecI evolution of PBP 2a- fusion of regulatory region of B-lactamase and PBP structural gene cellular levels of PBP 2a not correlate with MRSA intensity

    31. SCCMEC in MRSA

    32. Treatment Options-MRSA

    33. B-Lactam Resistance Mechanisms

    34. The Problem of Beta-lactamases

    35. Resistance Mechanism

    37. Ambler Classification Four major classes based on amino acid sequence similarity Class A; TEM, SHV, CTX-M ESBLs Class B; Metallo-enzymes Class C; AmpC Class D; Miscellaneous enzymes A,C and D have an active-site serine

    38. Bush Classification Sufficiently differentiates Ambler class A enzymes Based on four groups (1-4) and subgroups (a-f) ESBLs are designated as group 2be

    40. Extended-Spectrum ?-Lactamases (ESBL) Confers resistance to penicillins and 1st, 2nd and 3rd generation cephalosporins Inhibited by ?-Lactamase inhibitors Most common CTX-M, TEM and SHV >300 have been identified Plasmid-mediated, highly mobile Often associated with resistance genes to aminoglycoside, TMP/SMX and tetracycline Associated with fluoroquinolone resistance phenotype

    41. Types of ESBLs TEM SHV CTX-M OXA

    43. Increasing Prevalence of ESBL Producing E.coli and K. pneumoniae in Canada (2007-2009)

    44. MDR ESBL E.coli in Canada (Baudry et al. Antimicrob Agents Chemother 2008)

    45. Multi-Drug Resistance (MDR) Among ESBL Producing E.coli (n=19)

    46. Ertapenem Killing of ESBL E. coli Simulating T/MIC (1g IV OD, Cmax 14, t1/2 4 hrs) (Strain #64771; MIC: CTR 128 ug/ml, Levo 32ug/ml, Erta 0.25ug/ml)

    47. Causes of Antibiotic Resistance Overuse/abuse of antibiotics in humans Overuse/abuse of antibiotics in non-humans developing countries world travel critically ill patients industry advertising/promoting

    48. Antibiotic Use For Adults With (Viral) Coughs, Colds and Bronchitis by Family Physicians 21% of all prescriptions were for coughs, sore throats, colds, and bronchitis patients were treated with antibiotics in 51% colds 52% sore throat 66% bronchitis

    49. Correlation Between Ciprofloxacin Usage and Resistance in Pseudomonas aeruginosa (HSC Winnipeg, Canada 1989-1996)

    50. How do Antibiotics Promote Resistance Selection of resistant bacteria Societal effects Global spread

    51. Outpatient Antibiotic Use Compared to Europe* 2003

    52. Mechanisms of Antibiotic Resistance Alteration in target site (eg. MRSA, VRE, PRSP) inactivation/alteration of antibiotic (eg. B-Lactamases) decreased uptake (eg. P. aeruginosa) efflux (eg. S.aureus and fluoroquinolones)

    53. Genetics of Antibiotic Resistance Spontaneous mutation (eg. Fq, rifampin) Acquisition of new DNA transformation (S.pneumoniae) transduction (S.aureus) conjugation (? Enterococcus) Transposition Integrons

    54. Compensatory Mutations Ameliorate Costs of Antibiotic Resistance generally speaking both plasmid and chromosomal conferred resistance causes fitness losses (e.g. dt) when resistance has a cost, compensatory mutations (e.g. second-site mutations) can ameliorate these costs commonly without loss of resistance nature of compensatory changes is environment dependent (within or outside the host)

    55. Antibiotic Use in Developing Countries antibiotics available OTC poor patient compliance (1-2 days) cost (take subtherapeutic course) antibiotic quality is low counterfeit adulterated poor quality (potency)

    57. Antibiotic Use in Animals (Canada 2001-2003; by drug class)

    58. Potential Solutions to Infections Caused By Resistant Superbugs Knowledge about resistant infections (www.can-r.ca) Infection control (wash those hands !) Vaccination (eg. Influenza and S.pneumoniae) Appropriate antibiotic use (previous 3 months) Probiotics Discover and develop new antibiotics If treating a patient: Treat as early as possible Kill the pathogen

    59. Canadian Antimicrobial Resistance Alliance (CARA)

    61. Methods to Minimize Antibiotic Resistance Infection control (wash those hands !)

    62. Scissors May Spread Resistant Organisms HCW (including surgeons) carry scissors (communal) Voluntary/permission Scissors swabbed/planted 78.4% (182/232) scissors colonized with organisms Organisms: Gram-positive (S. aureus, Enterococci spp) Gram-negative (P. aeruginosa, Acinetobacter) Cleaning scissors with alcohol swab disinfected them.

    63. Potential Solutions to Infections Caused By Resistant Superbugs Knowledge about resistant infections (www.can-r.ca) Infection control (wash those hands !) Appropriate antibiotic use Vaccination (eg. Influenza and S.pneumoniae)

    64. Pneumococcal Vaccines PCV-7 (Prevnar?) in Canada 2000 23-valent PPV (PPV 23-Pneumovax?) introduced in 1983 Future PCV-10, PCV-13 etc

    65. Adult and Pediatric Antibiotic Prescriptions in Canada (1995-2005)

    66. Relative Risk of Clostridium difficile Infection (Antibiotic Exposure 45 days before index date)

    67. Probiotics Definition: live organisms that when administered in adequate amounts confer a health benefit to the host Normal, healthy, non-virulent bacteria Eg. Lactobacillus spp., Saccharomyces boulardii, Bifidobacterium spp. Available as foods, dietary supplements or as pharmaceuticals Tested vs untested products (eg. yogurt vs. specific probiotic product)

    68. Use of Probiotics in Diarrhea

    69. Probiotics - Unresolved Questions What is the best product(s) to use ? Does the method of delivery matter ? What dose to take ? What is the duration of treatment or prevention ? Other than imuunosuppressed individuals any other contra-indications or problems ? What is their role in human health ?

    70. ABCs of Treating Infectious Diseases Do not use the same antibiotic class as in previous 90 days Start treatment immediately If patients critically ill, you cant be wrong Use potent agents and dose aggressively (kill the pathogen) Dont treat for prolonged periods

    71. If Patient Critically ill-Treat ASAP (Effective Antimicrobial Therapy and Survival in Septic Shock - Treat Early)

    72. 72 Mortality Increases With Inadequate Initial Therapy in Critically ill ICU Patients Multiple studies conducted over the past two decades have found that inadequate initial antimicrobial therapy is an independent risk factor for mortality in patients with HAP.9-15 In each of these studies, mortality rates were higher for patients given initial inadequate therapy compared with patients given initial adequate therapy. Alvarez-Lerma et al. (1996) conducted a 12-month prospective study of patients with intensive care unit- (ICU) acquired pneumonia. Patients who received initial inadequate therapy had a significantly higher mortality rate compared with those who received initial appropriate therapy (24.7% versus 16.2%, p=0.0385).9 Rello et al. (1997) conducted a 38-month prospective study of patients with VAP. Patients who received initial inadequate therapy had a significantly higher attributable mortality rate than those who received initial appropriate therapy (37.0% versus 15.6%, p<0.05).10 Kollef et al. (1998) conducted a 12-month prospective study of patients with VAP. Patients who required a change in their therapy had a significantly higher mortality rate than those who received initial appropriate therapy (60.8% versus 33.3%, p<0.001).11 Luna et al. (1997) conducted a 44-month prospective study of patients with VAP. Patients who received initial inadequate antimicrobial therapy had significantly higher mortality rates than patients who received initial appropriate therapy (91% versus 38%, p<0.001).13 Ibrahim et al. (2000) conducted a 2-year prospective study of patients admitted to the ICU. Patients who received initial inadequate therapy had significantly higher mortality rates than those who received initial appropriate therapy (61.9% versus 28.4%, p<0.001).12 Harbarth et al. (2003) conducted a multicenter database study of patients (n=1342) with severe sepsis or early septic shock who were enrolled in a double-blind, controlled study of lenercept. Patients who received initial inadequate therapy had significantly higher mortality rates than those who received initial appropriate therapy (24% versus 39%, p<0.001).14 Valles et al. (2003) conducted a prospective, multicenter study conducted in 30 ICUs in Spain (April to December 1993 to April to December 1998) of 393 patients diagnosed with bloodstream infections, defined as true positive blood culture finding on ICU admission within first 48 h of ICU stay. In this study, inappropriate antimicrobial treatment was defined as microbiological documentation of blood culture infection that was not effectively treated when the causative pathogen and its antimicrobial susceptibility were known. A total of 63% of patients (290/339) who received appropriate treatment survived compared with 31% (49/339) of those who received inappropriate treatment.15 Multiple studies conducted over the past two decades have found that inadequate initial antimicrobial therapy is an independent risk factor for mortality in patients with HAP.9-15 In each of these studies, mortality rates were higher for patients given initial inadequate therapy compared with patients given initial adequate therapy. Alvarez-Lerma et al. (1996) conducted a 12-month prospective study of patients with intensive care unit- (ICU) acquired pneumonia. Patients who received initial inadequate therapy had a significantly higher mortality rate compared with those who received initial appropriate therapy (24.7% versus 16.2%, p=0.0385).9 Rello et al. (1997) conducted a 38-month prospective study of patients with VAP. Patients who received initial inadequate therapy had a significantly higher attributable mortality rate than those who received initial appropriate therapy (37.0% versus 15.6%, p<0.05).10 Kollef et al. (1998) conducted a 12-month prospective study of patients with VAP. Patients who required a change in their therapy had a significantly higher mortality rate than those who received initial appropriate therapy (60.8% versus 33.3%, p<0.001).11 Luna et al. (1997) conducted a 44-month prospective study of patients with VAP. Patients who received initial inadequate antimicrobial therapy had significantly higher mortality rates than patients who received initial appropriate therapy (91% versus 38%, p<0.001).13 Ibrahim et al. (2000) conducted a 2-year prospective study of patients admitted to the ICU. Patients who received initial inadequate therapy had significantly higher mortality rates than those who received initial appropriate therapy (61.9% versus 28.4%, p<0.001).12 Harbarth et al. (2003) conducted a multicenter database study of patients (n=1342) with severe sepsis or early septic shock who were enrolled in a double-blind, controlled study of lenercept. Patients who received initial inadequate therapy had significantly higher mortality rates than those who received initial appropriate therapy (24% versus 39%, p<0.001).14 Valles et al. (2003) conducted a prospective, multicenter study conducted in 30 ICUs in Spain (April to December 1993 to April to December 1998) of 393 patients diagnosed with bloodstream infections, defined as true positive blood culture finding on ICU admission within first 48 h of ICU stay. In this study, inappropriate antimicrobial treatment was defined as microbiological documentation of blood culture infection that was not effectively treated when the causative pathogen and its antimicrobial susceptibility were known. A total of 63% of patients (290/339) who received appropriate treatment survived compared with 31% (49/339) of those who received inappropriate treatment.15

    73. Treatment of Community Acquired Pneumonia: High Dose Short Course Levofloxacin vs. Low Dose Long Course Levofloxacin Each patient admitted to the study was assessed for the presence of several symptoms at study entry and after 3 days of therapy. Analysis of this data showed that there were differences between the two treatment regimens in the percentage of patients that resolved their symptoms by day 3 of therapy. A significantly higher percentage of patients receiving the 750-mg regimen resolved their fever (either measured or patient reported) by day 3 when compared to patients receiving the 500-mg dose. Other symptoms, such as presence of purulent sputum and shortness of breath, approached significance in favor of the 750-mg dose. Faster resolution of symptoms with the 750-mg dose can have significant clinical and economic benefits, and reveals a major advantage to use the 750-mg, short course levofloxacin therapy for the treatment of CAP over traditional regimens.Each patient admitted to the study was assessed for the presence of several symptoms at study entry and after 3 days of therapy. Analysis of this data showed that there were differences between the two treatment regimens in the percentage of patients that resolved their symptoms by day 3 of therapy. A significantly higher percentage of patients receiving the 750-mg regimen resolved their fever (either measured or patient reported) by day 3 when compared to patients receiving the 500-mg dose. Other symptoms, such as presence of purulent sputum and shortness of breath, approached significance in favor of the 750-mg dose. Faster resolution of symptoms with the 750-mg dose can have significant clinical and economic benefits, and reveals a major advantage to use the 750-mg, short course levofloxacin therapy for the treatment of CAP over traditional regimens.

    74. Mean Urinary Concentrations of Levofloxacin 750mg Dose (females with acute pyelonephritis)

    75. New Antimicrobials on the Horizon New fluoroquinolones/Topo Inh (nemonoxacin, flinafloxacin, JNJ-Q2, besifloxacin) Ketolides/Macs (cethromycin, CEM-101, EDP-420) Oxazolidinones (TR-700) Glycylcyclines ( PTK0796) Fluorocyclines (TP-271) Cephalosporins (ceftaroline, CXA-101, CXA-201) Carbapenems (razupenem,ME1036) Monobactams (BAL30072) Novel ?-lactamase inhibitors (NXL-104, Pip/BLI-489, MK-7655) Glyco/lipopeptides (oritavancin, MX-2401) New Aminoglycosides (ACHN-490) FabI inhibitors (AFN-1252, MUT37307) Pleromutilins (BC-3781) Oligomers of Sodium Alginate (Oligo-G) Peptide Deformylase Inhibitors (GSK-1322322, BB 83698) Methionyl tRNA synthase inhibitors (GSK-2251052) Antisense (Phosphorodiamidate morpholin oligomers-PMOs) Bacteriophages Monoclonals (tefibazumab) GSQ 7302 (SMAT-Small Molecule Anti-genomic Therapeutic) Diaminopyridines (Iclaprim, BAL30543-5) Efflux inhibitors (M-Pex MP601205) Hybrids (FQ/Rif, Glyco/Ceph)

    77. Potential Solutions to Infections Caused By Resistant Superbugs Knowledge about resistant infections (www.can-r.ca) Infection control (wash those hands !) Vaccination (eg. Influenza and S.pneumoniae) Appropriate antibiotic use (previous 3 months) Probiotics Discover and develop new antibiotics If treating a patient: Treat as early as possible Kill the pathogen

More Related