Upload
vicky-xie
View
18
Download
2
Embed Size (px)
DESCRIPTION
antibiotics
Citation preview
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 1/7
Author: Derek Moore Topic updated on 02/17/15 12:52pm 11Antibiotic Classification & Mechanism
Overview of By Mechanism
PENICILLINS CEPHALOSPORINS FLUOROQUINOLONES AMINOGLYCOSIDES MONOBACTAMS CARBAPENEMS MACROLIDES OTHER
Natrual First generation Ciprofloxacin (Cipro)
Levofloxacin
(Levaguin)
Moxifloxacin (Avelox)
Norfloxacin
Amikacin
Gentamicin
Kanamycin
Neomycin
Tobramycin
Aztreonam Ertapenem
Imienem
Meropenem
Azithromycin
Clarithromycin
Dirithromycin
Erythromycin
Clindamycin
Vancomycin
Rifampin
Doxycycline
Linezolid
Tetracycline
Trimethoprim/
sulfamethoxacole
Penicillin G
PenicillinVK
Cephalothin
Cefazolin (Ancef,
Kefzol)
Cephapririn
Cephalexin (Keflex)
other
Penicillinase
Resistant
Second Generation
Methicillin
Nafcillin
Oxacillin
other
Cefacor
Cefotetan (Cefotan)
other
Aminopenicillins Third Generation
Ampicillin Ceftriaxone
(Rocephin)
other
Fourth Generation
Cefpirome
Cefepime
Antibiotic Grouping By MechanismCell Wall Synthesis Penicillins
CephalosporinsVancomycin Betalactamase InhibitorsCarbapenemsAztreonamPolymycinBacitracin
Protein Synthesis InhibitorsInhibit 30s SubunitAminoglycosides (gentamicin)Tetracyclines Inhibit 50s Subunit
Ochronosis
Reiter's
Psoriatic Arthritis
Hemophilic Arthropathy
Blood Conditions
Fat Embolism Syndrome
Thromboembolism (PE & DVT)
Anticoagulation
Neurologic Diseases
Multiple Sclerosis
Amyotrophic Lateral Sclerosis(ALS)
Complex Regional PainSyndrome (CRPS)
Systemic Diseases
Rheumatoid Arthritis
Systemic Lupus Erythematosus(SLE)
Lyme Disease
Acute Rheumatic Fever
Metabolic Disease
Hypercalcemia
Hypocalcemia
Hypoparathyroidism
Hyperparathyroidism
Hypophosphatasia
Pseudohypoparathyroidism
Scurvy
Medications & Toxicity
Medications
Bisphosphonates
Prophylaxis Antibiotics
Antibiotic Classification &Mechanism
Antiinflammatory Medications
Analgesic Medications
Anesthesia
PlateletRich Plasma
Toxicology
Lead Toxicity
Clinical Science
Clinical Studies
Statistic Definitions
Level of Evidence
Clinical Trial Design
Outcome Measure Tools
Healthcare Worplace
Occupational Health
Legal and Ethics
Job Bank
Search Join now Login
Home QBank Cases Videos Posts Evidence Groups Colleagues Messages Feedback
Trauma Spine Sports Pediatrics Recon Hand Foot&Ankle Pathology Basic Science Anatomy Approaches
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 2/7
Inhibit 50s SubunitMacrolidesChloramphenicolClindamycinLinezolid Streptogramins
DNA Synthesis Inhibitors Fluoroquinolones Metronidazole
RNA synthesis Inhibitors RifampinMycolic Acid synthesis inhibitors IsoniazidFolic Acid synthesis inhibitors Sulfonamides
Trimethoprim
Antibiotic Classification & Indications
Inhibits Cell Wall SynthesisPenicillins
(bactericidal: blocks cross linking via competitive inhibition of the transpeptidase enzyme)Class/Mechanism Drugs Indications (**Drug of
Choice)Toxicity
Penicillin Penicillin GAqueous penicillin GProcaine penicillin GBenzathine penicillin GPenicillin V
Strep. pyogenes(Grp.A)**Step. agalactiae(Grp.B)**C. perfringens(Bacilli)**
HypersensitivityreactionHemolytic anemia
Aminopenicillins AmpicillinAmoxicillin Above +
↑ Gramnegative:E. faecalis**E. Coli**
Above
Penicillinaseresistantpenicillins
MethicillinNafcillinOxacillinCloxacillinDicloxacillin
Above +PCNaseproducingStaph.aureus
Above + Interstitial nephritis
Antipseudomonalpenicillins
CarbenicillinTicarcillin Piperacillin
Above +Pseudomonasaeruginosa**
Above
Cephalosporins(bactericidal: inhibits bacterial cell wall synthesis via competitive inhibition of the transpeptidase enzyme)
1st generation CefazolinCephalexin
Staph. aureus**Staph. epidermidis**Some Gramnegatives:E. ColiKlebsiella
Allergic reactionCoombspositiveanemia (3%)
2nd generation CefoxitinCefaclorCefuroxime
Above +↑ Gramnegative
Allergic ReactionETOH Disulfiramreaction
3rd generation CeftriaxoneCefotaximeCeftazidimeCefepime (4th generation)
Above +↑ GramnegativePseudomonas
Allergic ReactionETOH Disulfiramreaction
Other Cell Wall InhibitorsVancomycin (bactericidal: disruptspeptioglycan crosslinkage)
VancomycinMRSA**PCN/Ceph allegies**S. aureusS. epidermidis
Red man syndromeNephrotoxicityOtotoxicity
Betalactamase Inhibitors (bactericidal: blocking crosslinking)
Clavulanic AcidSulbactamTazobactam
S aureus**S epidermis**E.Coli**Klebsiella**
HypersensitivityReactionHemolytic anemia
Carbapenems Imipenem (+ cilastatin)Meropenem
Broadest activity ofany antibiotic
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 3/7
MeropenemDoripenemErtapenem
any antibiotic(except MRSA,Mycoplasma)
Aztreonam Aztreonam Gramnegative rodsAerobesHospitalacquiredinfections
Polymyxins Polymyxin BPolymyxin E
Topical Gramnegativeinfections
Bacitracin Bacitracin Topical Grampositiveinfections
Protein Synthesis InhibitionAnti30S ribosomal subunit
Aminoglycosides(bactericidal: irreversiblebinding to 30S)
GentamicinNeomycinAmikacinTobramycin Streptomycin
Aerobic GramnegativesEnterobacteriaceae Pseudomonas
NephrotoxicityOtotoxicity
Tetracyclines (bacteriostatic: blocks tRNA)
Tetracycline DoxycyclineMinocyclineDemeclocycline
RickettsiaMycoplasmaSpirochetes (Lyme'sdisease)
HepatotoxicityTooth discolorationImpaired growthAvoid in children <12 years of age
Anti50S ribosomal subunitMacrolides(bacteriostatic: reversiblybinds 50S)
ErythromycinAzithromycinClarithromycin
StreptococcusH. influenzaeMycoplamsapneumonia
CoumadinInteraction(cytochrome P450)
Chloramphenicol(bacteriostatic)
Chloramphenicol H influenzaeBacterial MeningitisBrain absces
Aplastic AnemiaGray BabySyndrome
Lincosamide(bacteriostatic: inhibitspeptidyl transferase byinterfering with amino acyltRNA complex)
ClindamycinBacteroides fragilisS aureusCoagulasenegativeStaph & StrepExcellent BonePenetration
PseudomembranouscolitisHypersensitivityReaction
Linezolid(variable)
Linezolid Resistant Grampositives
Streptogramins QuinupristinDalfopristin
VREGAS and S. aureusskin infections
DNA Synthesis InhibitorsFluoroquinolones
(bactericidal: inhibit DNA gyrase enzyme, inhibiting DNA synthesis)1st generation Nalidixic acid Steptococcus
MycoplasmaAerobic Gram +
PhototoxicityAchilles tendonruptureImpaired fracturehealing
2nd generation CiprofloxacinNorfloxacinEnoxacinOfloxacinLevofloxacin
As Above+Pseudomonas
as above
3rd generation Gatifloxacin As above + Grampositives
as above
4th generation MoxifloxacinGemifloxacin
As above + Grampositives + anaerobes
as above
Other DNA InhibitorsMetronidazole(bacteridical: metabolicbiproducts disrupt DNA)
Metronidazole (Flagyl) Anaerobics SeizuresCrebelar dysfunctionETOH disulframreaction
RNA Synthesis Inhibitors
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 4/7
RNA Synthesis InhibitorsRifampin(bactericidal: inhibits RNAtranscription by inhibiting RNApolymerase)
Rifampin StaphylococcusMycobacterium (TB)
Body fluiddiscolorationHepatoxicity (withINH)
Mycolic Acids Synthesis InhibitorsIsoniazid Isoniazidz TB
Latent TB
Folic acid Synthesis InhibitorsTrimethoprim/Sulfonamides (bacteriostatic: inhibition withPABA)
Trimethoprim/Sulfamethoxazole(SMX)SulfisoxazoleSulfadiazine
UTI organismsProteusEnterobacter
ThrombocytopeniaAvoid in thirdtrimester ofpregnancy
Pyrimethamine Pyrimethamine MalariaT. gondii
Bacteria Overview
Gram Postive CocciStaphylococcus Staph. aureus
MSSAMRSAStaph. epidermisStaph saprophyticus
Streptococcus Strep pneumoniaeStrep pyogenes (Group A) Strep agalacticae (Group B) Strep viridansStrep Bovis (Group D)
Enterococci E. faecalis (Group D strep)Gram Positive Bacilli
Spore FormingBacillus anthracisBacillus cereusClostridium tetaniClostridium botulinumClostridium perfringensClostridium difficile
NonSpore Forming Corynebacterium diphtheriaeListeria monocytogenesGram Negative Cocci
Neisseria Neisseria meningitidisNeisseria gonorrhoeaeGram Negative Bacilli
Enterics Escherichia coliSalmonella typhiSalmonella enteridisShigella dysenteriaeKlebsiella pneumoniaeSerratiaProteusCampylobacter jejuniVibrio cholerae Vibrio parahaemolyticus/vulnificus Helicobacter pyloriPseudomonas aeruginosaBacteroides fragilis
Respiratory bacilli Haemophilus influenzaeHaemophilius ducreyiBordatella pertussis
Zoonotic bacilli Yersinia enterocolitica Yersinia pestis Brucella Francisella tularensis Pasteurella multocida Bartonella henselae
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 5/7
Other Gardnerella vaginalisOther Bacteria
Mycobacteria Mycobacterium tuberculosisMycobacterium lepraeMOTTS
Spirochetes Borrelia burgdorferiLeptospira interrogansTreponema pallidum
Chlamydiaceae Chlamydia trachomatisChlamydophila RickettsiaEhrlichia
Mycoplasmataceae Mycoplasma pneumoniaeUreaplasma urealyticum
Funguslike Bacteria Actinomyces israeliiNocardia
Antibiotic Resistance Mechanisms
Bacteria develop ability to hydrolyze these drugs using β lactamaseconfers resistance to penicilline.g. E. coli, Staph epidermidis, Pseudomonas aeruginosa, Klebsiella pneumoniaeadd β lactamase inhibitor e.g. clavulanic acid in amoxicillinclavulanate (Augmentin)
Genetic mutation of mecAa bacterial gene encoding a penicillinbinding protein. New PBP has reduced affinity forantibioticsconfers resistance to methicillin, oxacillin, nafcilline.g. MRSA
Altered cell wall permeabilityconfers resistance to tetracyclines, quinolones, trimethoprim and β lactam antibiotics
Creation of biofilm barrier provides an environment where offending bacteria can multiply safe from the hoste immunesystem
SalmonellaStaph epidermidis
Active efflux pumpsconfers resistance to erythromycin and tetracyclinee.g. msrA gene in Staph
Altered peptidoglycan subunit (altered DalanylDalanine of NAM/NAGpeptide) confers resistance to vancomycine.g. vancomycin resistant enterococcus (VRE)
Ribosome alterationerm gene confer inducible resistance to MLS (macrolide lincosamide streptogranin) agentsvia methylation of 23s rRNAdemonstrate using D zone test
for inducible clindamycin resistance in Staph and beta hemolytic Strep
Penicillins
Mechanisminterfer with bacterial cell wall synthesis
Subclassification and tested examplesnatural
penicillin Gpenicillinaseresistant
methicillin (Staphcillin)aminopenicillins
ampicillin (Omnipen, Polycillin)
Cephalosporins
Overviewbactericidal
Mechanismdisrupts the synthesis of the peptidoglycan layer of bacterial cell walls
does so through competitive inhibition on PCB (penicllin binding proteins)peptidoglycan layer is important for cell wall structural integrity.
same mechanicsm of action as betalactam antibiotics (such as penicillins)Subclassification and tested examples
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 6/7
Subclassification and tested examples first generation
cefazolin (Ancef, Kefzol)second generation
cefaclor (Ceclor)third generation
cefriazone (Rocephin)fourth generation
cefepime (Maxipime)
Fluoroquinolones
Mechanismblocks DNA replication via inhibition of DNA gyrase
Side effectsinhibit early fracture healing through toxic effects on chondrocytes increased rates of tendinitis, with special predilection for the Achilles tendon.
tenocytes in the Achilles tendon have exhibited degenerative changes when viewedmicroscopically after fluoroquinolone administration.recent clinical studies have shown an increased relative risk of Achilles tendon ruptureof 3.7.
Subclassification and tested examples ciprofloxacin (Cipro)levofloxacin (Levaquin)
Aminoglycosides
Mechanismbactericidalinhibition of bacterial protein synthesis
work by binding to the 30s ribosome subunit, leading to the misreading of mRNA. Thismisreading results in the synthesis of abnormal peptides that accumulate intracellularlyand eventually lead to cell death. These antibiotics arebactericidal.
Subclassification and tested examples gentamicin (Garamycin)
Vancomycin
Coveragegrampositive bacteria
Mechanismbactericidalan inhibitor of cell wall synthesis
Resistanceincreasing emergence of vancomycinresistant enterococci has resulted in the developmentof guidelines for use by the (CDC) indications for vancomycin
serious allergies to penicillins or betalactam antimicrobials serious infections caused by susceptible organisms resistant to penicillins (MRSA,MRSE)surgical prophylaxis for major procedures involving implantation of prostheses ininstitutions with a high rate of MRSA or MRSE
Rifampin
Most effective against intracellular phagocytized Staphylococcus aureus in macrophages
Linezolid
Linezolid binds to the 23S portion of the 50S subunit and acts by preventing the formation ofthe initiation complex between the the 30S and 50S subunits of the ribosome.
Splenectomy
Splenectomy patients or patients with functional hyposplenism require the following vaccinesand/or antibiotics
Pneumococcal immunizationHaemophilus influenza type B vaccineMeningococcal group C conjugate vaccineInfluenza immunizationLifelong prophylactic antibiotics (oral phenoxymethylpenicillin or erythromycin)
4/15/2016 Antibiotic Classification & Mechanism Basic Science Orthobullets.com
http://www.orthobullets.com/basicscience/9059/antibioticclassificationandmechanism 7/7
Next Question
Please Rate Educational Value! Average 3.0 of 42 Ratings
Qbank (11 Questions)
Question: 1 of 10
TAG
(OBQ12.53) What mechanism allows Staphylococcus epidermidis to adhere to surfaces and resist phagocytosis? Review Topic
1. Creation of active efflux pumps2. Methylation of 23s rRNA3. Biofilm production4. Alteration of cell wall permeability5. Betalactamase production
PREFERRED RESPONSE ▶
Evidence
evidenceFootprint
Key
Tested (/Site/EFootprints/ViewForTopic/9059?mode=Tested)All (/Site/EFootprints/ViewForTopic/9059?mode=All)
Clinical Impact (increase →)
Cost Effectiveness (more →)
0.00 1 2 3 4 5
0%
20%
40%
60%
80%
100%
Topic Comments
Please login to add comment.
SHOW EVIDENCE