II. Epidemiology

  1. Health Care Associated Infections are caused by multidrug resistant organisms in 16% of cases (especially MRSA)

III. Pathophysiology: Factors Affecting Drug Resistance

  1. Antibiotic Overuse
    1. Viral Upper Respiratory Infections
    2. Agricultural Antibiotic use
  2. Increasing Incidence of Immunocompromised patients
  3. Food supply globalization

IV. Mechanisms: Beta-Lactamase

  1. Beta-Lactams (Penicillins and Cephalosporins) inhibit transpeptidase
  2. Transpeptidase cross-links peptidoglycan mesh in the synthesis of the Bacterial cell wall
    1. Beta-Lactams inhibition of Transpeptidase results in lysis and death of the Bacterial cell
  3. Beta-Lactams are inactivated by the enzyme Beta-Lactamase
    1. Beta-Lactamase is produced by beta-lactam resistant Bacteria
  4. Several Antibiotics have since been developed to be resistant to Beta-Lactamase
    1. Beta-Lactamase Resistant Penicillins include Dicloxacillin and Nafcillin

V. Causes: Emerging Drug Resistance

  1. Methicillin Resistant Staphylococcus Aureus (MRSA)
  2. Penicillin Resistant Pneumococcus
  3. Vancomycin Resistant Enterococcus (VRE)
  4. Multi-resistant Gram Negative Bacilli
    1. ESBL-Producing Enterobacteriaceae
    2. Carbapenem-Resistant Enterobacteriaceae (CRE)
    3. Carbapenem-Resistant Klebsiella
    4. AmpC Beta-Lactamase-Producing Enterobacteriaceae (typically respond to Cefepime)
      1. Enterobacter cloacae
      2. Klebsiella aerogenes
      3. Citrobacter freundii
    5. Pseudomonas aeruginosa resistance
    6. Nosocomial outbreaks
    7. Restricted drug use sometimes beneficial
  5. Multi-Resistant Neisseria Gonorrhea
  6. Multi-Resistant Tuberculosis
  7. Carbapenem-Resistant Acinetobacter Baumannii
    1. Lung and Wound Infections or colonization
    2. Treated with high dose Unasyn (>= 6g sulbactam) AND Minocycline, Tigecycline or polymyxin B
    3. May be sensitive to Cefiderocol
  8. Stenotrophomonas maltophilia
    1. Lung and Wound Infections in Immunocompromised patients (esp. Hematologic Malignancy)
    2. Treated with two of the following: TMP-SMZ, Minocycline, Tigecycline, cifiderocol, Levofloxacin
    3. Alternatively treated with Ceftazidime-Avibactam AND Aztreonam

VI. Prevention

  1. Antibiotic Stewardship
    1. Limit Antibiotics to cases in which they are absolutely indicated
  2. Prevent spread
    1. See Health Care-Associated Infection
    2. See Personal Protection Equipment
    3. Practice good Hand Hygiene before and after seeing each paint
    4. Follow contact precautions for colonized or infected patients
    5. Consider culturing for nasal MRSA in high risk hospital settings (e.g. ICU) and decolonization with Bactroban of infected patients
  3. Decolonization
    1. Chlorhexidine baths daily for Intensive Care unit patients (esp. MRSA, VRE patients)

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Ontology: beta-Lactamase (C0597979)

Definition (NCI) An enzyme that brings about the hydrolysis of a beta-lactam (as penicillin to penicilloic acid); found in most staphylococcus strains that are naturally resistant to penicillin.
Definition (CSP) enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.
Definition (MSH) Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.
Concepts Amino Acid, Peptide, or Protein (T116) , Enzyme (T126)
MSH D001618
SnomedCT 79744009
LNC LP20680-2
English beta Lactamase, beta Lactamases, beta-Lactamase, beta-Lactamases, beta-Lactamhydrolase, beta lactam hydrolase, beta-lactamases, beta-Lactamases [Chemical/Ingredient], Beta lactamase, beta lactamases, beta lactamase, beta-lactamase, Beta lactamases, beta-Lactamase (substance), Beta-Lactamase
German Beta-Lactamase, Beta-Laktamasen, Beta-Laktamase, Beta-Lactamasen
Swedish Betalaktamaser
Czech beta-laktamasy
Finnish Beetalaktamaasit
French bêta-Lactamase, bêta-Lactamases
Russian BETA-LAKTAMAZY, БЕТА-ЛАКТАМАЗЫ
Japanese ベータ-ラクタマーゼ, β-ラクタマーゼ, ベータラクタマーゼ
Croatian BETA-LAKTAMAZE
Polish Beta-laktamazy
Norwegian Betalaktamaser, Betalaktamase
Spanish beta - lactamasa (sustancia), beta - lactamasa, beta-Lactamasas
Italian Beta-lattamasi
Portuguese beta-Lactamases

Ontology: Antibiotic Resistance, Microbial (C0949285)

Definition (NCI) The mechanisms, functions, activities, or processes exhibited by microorganisms, especially bacteria, to resist or to become tolerant to antibiotics.
Definition (NCI_CDISC) The mechanisms, functions, activities, or processes exhibited by microorganisms, especially bacteria, to resist or to become tolerant to antibiotics.
Concepts Organism Attribute (T032)
MSH D004352
ICD10 Z16.20
English Antibiotic Resistance, Resistance, Antibiotic, antibiotic resistance, Resistance to antibiotics NOS, ANTIBIOTIC RESISTANCE, Antibiotic Resistance, Microbial
Czech rezistence na antibiotika
Portuguese Resistência a Antibióticos, Resistência Microbiana a Antibióticos
Spanish Resistencia a Antibióticos, Resistencia Microbiana a Antibióticos
French Résistance microbienne aux antibiotiques, Antibiorésistance, Résistance des microbes aux antibiotiques
German Antibiotikaresistenz, Antibiotikaresistenz, mikrobielle
Croatian OTPORNOST MIKROBA NA ANTIBIOTIKE
Italian Resistenza microbica agli antibiotici, Resistenza agli antibiotici
Dutch Geneesmiddelenresistentie, microbiële

Ontology: Antimicrobial Resistance (C1456627)

Concepts Clinical Attribute (T201)
English Antimicrobial Resistance