Research

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Research

• Mekeleya Yimen
• Michelle Ritter
• March 29, 2007

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Project

• Clinical characteristics and outcomes of patients
  infected with Acinetobacter Baumannii at a
  Tertiary Care Hospital

3
Project

• Clinical characteristics and outcomes of patients
  infected with Acinetobacter Baumanii at a
  Tertiary Care Hospital
• Clinical characteristic and outcomes

4
Project

• Clinical characteristics and outcomes of patients
  infected with Acinetobacter Baumannii at a
  Tertiary Care Hospital
• Clinical characteristic and outcomes
• Predictors of length of stay and mortality

5
Project

• Clinical characteristics and outcomes of patients
  infected with Acinetobacter Baumannii at a
  Tertiary Care Hospital
• Clinical characteristic and outcomes
• Predictors of length of stay and mortality
• Antibiotic susceptibility

6
Project

• Clinical characteristics and outcomes of patients
  infected with Acinetobacter Baumanii at a
  Tertiary Care Hospital
• Clinical characteristic and outcomes
• Predictors of length of stay and mortality
• Antibiotic susceptibility
• Correlate site of infection with patient outcomes

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Background

• Emergence of Acinetobacter Baumanii
• Since 1963 A. Baumanii has become an increasingly
  important pathogen causing many nososcomial
  infections (1)
• In a study conducted in 2004 1.3 of health
  care associated blood stream infections were due
  to this organism(1)
• Out of these, increased number of infection was
  found in military medical facilities
• During Vietnam war A. Baumannii was the most
  common GNB recovered from traumatic injuries
• During Recent years service members injured in
  Afghanistan/Iraq/Kuwait had increased prevalence
  of bloodstream infection secondary to this
  organism (1)

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Background

• Microbiology
• Acinetobacter baumannii (A. baumannii) is a
  pleomorphic aerobic gram-negative bacillus
• Widely distributed in nature (soil, water, food,
  sewage)
• Survives on moist dry surfaces
• Different climates and environmental conditions
• Long survival time on inanimate surfaces
• In vitro survival time 329 days
• Up to 4 months on dry surfaces

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Background
D

• Microbiology
• Clinically significant as a pathogen when
  isolated from blood, sterile body sites or as a
  dominant organism isolate
• Emerging as an important Pan-resistant GNB
  worldwide
• hospital outbreaks
• few lineages achieve epidemic status, reaching
  multiple hospitals or countries (2)

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Background

• Bed rails
• Bedside tables
• Ventilators
• Infusion pumps
• Mattresses
• Pillows
• Air humidifiers
• Patient monitors

• X-ray view boxes
• Curtain rails
• Curtains
• Equipment carts
• Sinks
• Ventilator circuits
• Floor mops

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Background

• Highly antibiotic resistant
• Numerous mechanisms of resistance
• ß-lactamase activity
• Changes in Penicillin Binding proteins
• Impaired permeability through porins
• carbapenem hydrolyzing oxacillinase
• amino glycoside-modifying enzymes
• Mutations in DNA gyrase
• Transmission of resistance thru
• Integrons (mobile circular DNA elements)
• Plasmids
• transposons

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Background

• Emergence of Multi-drug resistance
• Conflicting literature regarding acquisition of
  Multi drug-Resistant (MDR) A. baumannii
• MDR A. baumannii from the environment/field i.e.
  sporadic?
• Colonization with A. baumannii followed by
  antibiotic selection pressure?

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Background

• Most common infections caused by A. Baumannii
• Ventilator-associated pneumonia
• Urinary tract infections
• Bloodstream infections
• Skin/wound infections

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Study Rationale

• The emergence of multi drug resistant gram
  negative pathogens in hospitalized patients
  continues to be an increasingly important problem
  that could contribute to patient length of stay
  and patient outcome
• Pseudomonas Aeruginosa
• Extended spectrum beta lactamase producing E.
  Coli and Klebsiella species
• S. maltophilia
• A. baumannii

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Study Rationale

• Prevalence of MDR Acinetobacter
• Limited antibiotics available to effectively
  treat MDR Acinetobacter
• Morbidity and mortality
• Increased prevalence of MRD Acinetobacter in
  health care setting and in the community

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Study Design

• Retrospective chart review
• Patients will be identified
• using our microbiology laboratory data base
• those with a positive culture for A. baumannii
  will be included in the study
• All patients with positive cultures from December
  1, 2004- December 31, 2006
• A standardized data abstraction form will be
  used to collect information on all eligible
  patients

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Abstraction Data

• Reason for admission
• Past medical history
• Sites of infection/colonization
• Infections caused by A. baumannii
• Other organisms causing Co-infection/co-transmitte
  d
• Prior antibiotic treatment/prior hospitalization
• Efficacy of antibiotic therapy
• Other lab abnormalities associated with infection

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OBJECTIVES

• Primary
• Determine
• the clinical characteristics
• risk factors
• outcomes in patients infected with A. baumannii
• Determine predictors of
• length of stay
• mortality of patients infected with A. baumannii
• Describe the antibiotics susceptibility pattern
  of A. baumannii at a tertiary care teaching
  hospital

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A. baumannii Ventilator Associated Pneumonia
(VAP)

• Acinetobacter accounts for 5-25 of all cases of
  VAP
• Risk factors
• Advanced age
• Chronic lung disease
• Immunosuppression
• Surgery
• Use of antimicrobial agents
• Invasive devices
• Prolonged ICU stay

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A. baumannii susceptibility at GUH February
2005-2006
21
A. baumannii susceptibility at GUH March
2006-August 2006
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OBJECTIVES

• Secondary
• Compare clinical characteristics and outcomes
  (length of stay and mortality) in patients
  infected with Carbapenem resistant A. baumannii
  vs. Carbapenem sensitive A. baumannii
• Correlate
• the clinical impact of the site of infection of
  A. baumannii and its regard with patient outcome
• prior antibiotic exposure with the development of
  Carbapenem resistant A. baumannii infection
• Assess the pharmacoeconomic impact of A.
  baumannii infections

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Questions?

• What are the risk factors and clinical outcomes
  at our institution?
• Are we causing a selection bias MDR Acinetobacter
  with frequent use of certain antibiotics?
• What is our resistance profile in this
  institution and did it change over the course of
  the study?

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The END!
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References

• Acinetobacter Baumannii infections Among Patients
  at Military Medical facilities treating injured
  US Service Members, 2002-2004. Scott, PT et al.
  MMWR Nov 200453(45)1063-1066
• Risk Factors for an Outbreak of
  Multi-Drug-Resistant Acinetobac Nosocomial
  Pneumonia Among Intubated Patients. Chest.
  1999115 1378-1382
• Multidrug-resistant Acinetobacter Infection
  Mortality Rate and Length of Hospitalization.
  Sunenshine, R.H et al EID January 2007 Volume
  131
• Wagenvoort JHT et al. J Hosp Infect.
  200252226-229
• Webster C et al. Infect Control Hosp Epidemiol.
  200021246
• Wendt C et al. J Clin Microbiol.
  1997351394-1397
• Murray CK et al. CID. 2006 43 383-384
• Jain et al. Ann Pharmacoth. 2004 38 1449-1459
• Cisneros JM et al. J Clin Microbiol. 2002 8
  687-69
• Davis KA et al. EID. 2005 11 1218-1224
• Poirel L et al. J Clin Microbiol. 2006 12
  826-836

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Acknowledgement

• Dr. Timpone
• Dr. Kumar
• Dr. Qasba