Download - Mtalib baumannii acinetobacter 2

  • Acinetobacter baumannii Maliha Talib MB 360 (Lee) Spring 2014

  • Traced back to Vietnam WarRecent outbreak during Iraq WarOriginal outbreak from Europe>> 700 soldiers effectedOrigination

  • General InformationTaxonomic Classification: Bacteria; Proteobacteria; Gammaproteobacteria; Pseudomonadales; Moraxellaceae; Acinetobacter

    Microbiologic Morphology: gram negative aerobic cocco-bacillusencapsulatednonmotile catalase-positiveoxidase-negative

  • Catalase = positive The purpose is to see if the microbe has catalase or can destroy chemical hydrogen peroxide.Oxidase = negative Identifies organisms that produce the enzyme cytochrome oxidase.

    General Information

  • General InformationHabitatsoil, water, food, sewage, & the hospital environmentresistant to desiccation and disinfectionSurvive on moist & dry surfacesforms bio-film on catheters, ventilators, and other medical devicesIraq/Afghanistan

  • General Information

  • General Information

  • Nutritiongrows on various media can live in hospital settings 9 days after patient leavesAcinetobacter calcoaceticus-baumanii complex: glucose-oxidising nonhemolytic, Acinetobacter lwoffii: glucose-negative nonhemolytic Acinetobacter haemolyticus: haemolytic on blood agar. General Information

  • PathogenesisDiseasesBloodstream infections: pneumonia, urinary tract infections, and septicemiamostly respiratory >> can lead to death 32 species: cause of 80% of infections nosocomial Examples of Major InfectionsVentilator-associated pneumonia Urinary tractBloodstream infection Secondary meningitisSkin/wound infectionsEndocarditisCAPD-associated peritonitisVentriculitis

  • Pathogenesis

  • Pathogenesis

  • Transmission spread via person to person OR contact with contaminated environmentPathogenesis

  • Pathogenesis

  • Bed railsBedside tablesVentilatorsInfusion pumpsMattressesPillowsAir humidifiersPatient monitorsX-ray view boxesCurtain railsCurtainsEquipment cartsSinksVentilator circuitsFloor mopsTransmission Pathogenesis

  • Mechanisms Aminoglycosides-modifying enzymes Broad-spectrum -lactamases Carbapenemases Quantitative and/or qualitative changes in outer membrane porins Altered penicillin-binding proteins.


  • Circular map of A. baumannii genome. Smith M G et al. Genes Dev. 2007;21:601-614Copyright 2007, Cold Spring Harbor Laboratory PressPathogenesis

  • PathogenesisSymptomsstandard infection symptoms i.e. feverdeath within 14 days of surgery Predisposed factors MalignancyTraumaBurnsSurgical wound infectionsNeonates Low birth weightNeed for mechanical ventilationDiagnosisclinical culture of blood, sputum, urine, wound, sterile body fluid, etc.

  • Factors leading to the emergence and transmission of multidrug-resistant (MDR) Acinetobacter species. Eliopoulos G M et al. Clin Infect Dis. 2008;46:1254-1263 2008 by the Infectious Diseases Society of America

  • Treatment Will collect: age, sex, occupation, hospital location at the time of positive culture (ER, medical ward, ICU etc), date of positive culture, prior hospitalization, receipt of outpatient dialysis, home care or other regular medical care (eg, outpatient chemotherapy), presence of invasive devices, receipt of antibiotics, etc.Carbapenems (Imipenem and Meropenem) - growing resistanceOthers: Polymyxin, Tigecycline and Aminoglycosides Pathogenesis

  • Pathogenesis

  • Pathogenesis

  • Methods for control and prevention of multidrug-resistant Acinetobacter infection.PathogenesisPrevention: Wash handscontact precautionsenvironmental decontamination

  • Antibiotic Resistancenaturally transformableAcomFECB and comQLONM allow uptake of DNA from the environment administration of subtheraputic doses of antimicrobial agents, drug overuse, interrupted courses of treatment, and poor tissue penetration by antimicrobial agentMedical interventions increasing the Acinetobacter Infections

  • Most A. baumannii resistant: tampicillin, Carbenicillin, Cefotaxime and Chloramphenicol.Increasing resistance:Gentamycin, tobramycin and amikacin is increasing. May retain: Fluoroquinolones, ceftazidime,Trimethoprim-Sulphmethoxazole, Doxycycline, Polymyxin B, colistin, imipenem and meropenemAntibiotic Resistance

  • "Acinetobacter baumannii membrane transporter PilQ allows initial entry of foreign DNA into the cell. Foreign DNA is then bound by protein ComE and is directed to cytoplasmic membrane transporter ComA."Antibiotic Resistance

  • Sent troops to IraqBush's increase of troops to protect Baghdad and Al Anbar ProvinceAntibiotic Resistance

  • Cost of Outbreak

  • Works Cited

    Federico Perez, Andrea M. Hujer, Kristine M. Hujer, BrookeK. Decker, Philip N. Rather and Robert A. Bonomo Antimicrob. Agents Chemother. 2007, 51(10):3471. DOI:10.1128/AAC.01464-06. Published Ahead of Print 23 July 2007. George M. Eliopoulos, Lisa L. Maragakis, and Trish M. Perl Acinetobacter baumannii: Epidemiology, Antimicrobial Resistance, and Treatment Options Clin Infect Dis. (2008) 46 (8): 1254-1263 doi:10.1086/529198Hujer, K. Hujer, A. Hulten, E. Bajaksouzian, S. Adams, J. Donskey, C. Ecker, D. Massire, C. Eshoo, M., Sampath, R., Thomson, J. Rather, P., Craft, D., Fishbain, J., Ewell, A., Jacobs, M. Paterson, D., Bonomo, R. Analysis of Antibiotic Resistance Genes in Multidrug-Resistant Acinetobacter sp. Isolates from Military and Civilian Patients treated at the Walter Reed Army Medical Center. Antimicrboia Agents and Chemotherapy. Dec. 2006. Volume. 50, No. 12. 4114-4123.Jos M. Cisneros, Maria J. Reyes, Jernimo Pachn, Berta Becerril, Francisco J. Caballero, Jos L. Garca Garmendia, Carlos Ortiz, and Adelaido R. Cobacho Bacteremia Due to Acinetobacter baumannii: Epidemiology, Clinical Findings, and Prognostic Features Clin Infect Dis. (1996) 22 (6): 1026-1032 doi:10.1093/clinids/22.6.1026Lenie Dijkshoorn, Alexandr Nemec & Harald Seifert An increasing threat in hospitals: multidrug-resistant Acinetobacter baumannii Nature Reviews Microbiology 5, 939-951 (December 2007) doi:10.1038/nrmicro1789Mortensen, B. L. and Skaar, E. P. (2012), Hostmicrobe interactions that shape the pathogenesis of Acinetobacter baumannii infection. Cellular Microbiology, 14: 13361344. doi: 10.1111/j.1462-5822.2012.01817.x

    Circular map of A. baumannii genome. The outermost circle shows genes color-coded by COG assignment: (gold) translation, ribosomal structure and biogenesis; (orange) RNA processing and modification; (dark orange) transcription; (maroon) DNA replication, recombination, and repair; (yellow) cell division and chromosome partitioning; (light pink) defense mechanisms; (purple) signal transduction mechanisms; (peach) cell envelope biogenesis, outer membrane; (medium purple) cell motility and secretion; (dark pink) intracellular trafficking, secretion, and vesicular transport; (light green) post-translational modification, protein turnover, chaperones; (lavender) energy production and conversion; (blue) carbohydrate transport and metabolism; (red) amino acid transport and metabolism; (green) nucleotide transport and metabolism; (light blue) coenzyme metabolism; (cyan) lipid metabolism; (dark purple) inorganic ion transport and metabolism; (sea green) secondary metabolites biosynthesis, transport, and catabolism; (light gray) general function prediction only; (ivory) function unknown; (dark gray) not in COGs. The middle circle represents the G+C percentage, colored red for regions above median GC score (38%) and blue for regions less than or equal to the median. The blue boxes indicate pAs, the yellow boxes indicate islands predicted to be involved in pathogenicity through homology and sequence composition differences, and the red and orange boxes indicate islands confirmed by the screens. The circles were drawn using the program GenomeViz (