antibiotic classes
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Antibiotic classesTRANSCRIPT
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A Review of Antibiotic Classes
Khaled Saad Zaghloul2014
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Bacter ia by Site of InfectionMouth Peptococcus Peptostreptococcus Actinomyces
Skin/Soft Tissue S. aureus S. pyogenes S. epidermidis Pasteurella
Bone and Joint S. aureus S. epidermidis Streptococci N. gonorrhoeae Gram-negative rods
Abdomen E. coli, Proteus Klebsiella Enterococcus Bacteroides sp.
Urinary Tract E. coli, Proteus Klebsiella Enterococcus Staph saprophyticus
Upper Respiratory S. pneumoniae H. influenzae M. catarrhalis S. pyogenes
Lower Respiratory Community S. pneumoniae H. influenzae K. pneumoniae Legionella pneumophila Mycoplasma, Chlamydia
Lower Respiratory Hospital K. pneumoniae P. aeruginosa Enterobacter sp. Serratia sp. S. aureus
Meningitis S. pneumoniae N. meningitidis H. influenza Group B Strep E. coli Listeria
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Beta-Lactam Structure
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Discovery of penicillin
Alexander Fleming1928
Nobel Prize, 1945
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β-Lactam Characteristics
Same mechanism: Inhibit cell wall synthesis Bactericidal (except against Enterococcus
sp.) Short elimination half-life Primarily renally eliminated (except
nafcillin, oxacillin, ceftriaxone, cefoperazone) Cross-allergenicity - except aztreonam
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β-lactamsPharmacology
• Absorption: Variable depending on product• Distribution:
Widely distributed into tissues and fluids Pens only get into CSF in the presence of inflamed
meninges; parenteral 3rd and 4th generation cephs,meropenem, and aztreonam penetrate the CSF
• Elimination: most eliminated primarily by the kidney, dosage adj
required in the presence of renal insufficiency Nafcillin, oxacillin, ceftriaxone -eliminated by the liver ALL β-lactams have short elimination half-lives except for
a few cephalosporins (ceftriaxone)
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β-LactamsAdverse Effects
• Hypersensitivity……3 to 10 %Higher incidence with parenteral
administrationMild to severe allergic reactions – rash to
anaphylaxis and deathAntibodies produced against metabolic by-
products or penicillin itselfCross-reactivity exists among all penicillins
and even other β-lactams
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β-LactamsAdverse Effects
• Neurologic – especially with penicillins andcarbapenems (imipenem and meropenem)Especially in patients receiving high doses in
the presence of renal insufficiency Irritability, confusion, seizures
• Hematologic:Leucopenia, neutropenia, thrombocytopenia –
prolonged therapy (> 2 weeks)
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β-LactamsAdverse Effects
• Gastrointestinal:Nausea, vomiting, diarrhea, pseudomembranous
colitis (C. difficile diarrhea)• Interstitial Nephritis:Cellular infiltration in renal tubules (Type IV
hypersensitivity reaction – characterized byabrupt increase in serum creatinine; can lead torenal failure
Especially with methicillin or nafcillin
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Timeline of antibiotic resistance
• 1942 - penicillin available• 1942 - penicillin resistant S. aureus• 1940’s-1950’s - chlorampenicol, tetracycline,
erythromycin resistance• Early ‘60s - β-lactamase resistant penicillins available• Late ‘70s - MRSA arose (methicillin resistant S. aureus)• 1997 - first vancomycin resistant Enterococcus reported• July 2002 - CDC reported first case of vancomycin-
resistant S. aureus in US
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Natural Penicillins(penicillin G, penicillin V)
Gram-positive Gram-negativepen-susc S. aureus Neisseria sp.pen-susc S. pneumoniaeGroup streptococci Anaerobesviridans streptococci Clostridium sp.EnterococcusOtherTreponema pallidum (syphilis)
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Aminopenicillins(ampicillin, amoxicillin)
Developed to increase activity againstgram-negative aerobesGram-positive Gram-negativepen-susc S. aureus Proteus mirabilisGroup streptococci Salmonella, Shigellaviridans streptococci some E. coliEnterococcus sp. H. influenzaeListeria monocytogenes
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Penicillinase-Resistant PenicillinsAntistaphylococcal Penicillins
(nafcillin, oxacillin, methicillin, cloxacillin, dicloxacillin, flucloxacillin)
Developed to overcome the penicillinaseenzyme of S. aureus which inactivatednatural penicillins
Gram-positivemethicillin-susceptible S. aureusGroup streptococciviridans streptococci
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CarboxypenicillinsAntipseudomonal Penicillins
(carbenicillin, ticarcillin)Developed to further increase activityagainst resistant gram-negative aerobesGram-positive Gram-negative
marginal Proteus mirabilisSalmonella, Shigellasome E. coliH. influenzaeEnterobacter sp.Pseudomonas aeruginosa
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UreidopenicillinsAntipseudomonas Penicillins(piperacillin, azlocillin, mezlocillin)
Developed to further increase activityagainst resistant gram-negative aerobesGram-positive Gram-negative viridans strep Proteus mirabilisGroup strep Salmonella, Shigellasome Enterococcus E. coli
H. influenzaeAnaerobes Enterobacter sp.Fairly good activity Pseudomonas aeruginosa
some Klebsiella sp.
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β-Lactamase Inhibitor Combination(Unasyn, Augmentin, Tazosyn)
Developed to gain or enhance activity against β-lactamase producing organisms.Gram-positive Gram-negativeS. aureus H. influenzae
E. coliAnaerobes Proteus sp.Bacteroides sp. Klebsiella sp.
Neisseria gonorrhoeaeMoraxella catarrhalis
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IV to PO - Penicillins
*Penicillin to Penicillin*Ampicillin to Amoxicillin*Unasyn to Augmentin
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Classification and Spectrum of Activity of Cephalosporins
• Divided into 4 major groups called“Generations”
• Are divided into Generations based on: antimicrobial activity resistance to beta-lactamase
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Classification of Parenteral and Oral Cephalospor ins
Cephalospor ins 1st gen 2nd gen 3rd gen 4th gen
*Parenteral Cefazolin Cefamandole Cefoperazone Cefepime
Cephalexin Cefuroxime Cefotaxime Cefpirome
Cephapirin Ceftazidime
Cephradine Ceftriaxone
*Oral Cefadroxil Cefaclor Cefdinir
Cephalexin Cefprozil Cefpodoxime
Cephradine Cefuroxime-axetil Cefixime
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First Generation Cephalosporins Cefadroxil, Cephradine Cefazolin, Cephalexin
Best activity against gram-positiveaerobes, with limited activity against afew gram-negative aerobes, they arecommonly used for management of skinand soft tissue infections.
Gram-positive Gram-negativemeth-susc S. aureus E. colipen-susc S. pneumoniae K. pneumoniaeGroup streptococciViridans streptococci
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Second Generation Cephalosporins
Spectrum of ActivityGram-positive Gram-negativemeth-susc S. aureus E. colipen-susc S. pneumoniae K. pneumoniaeGroup streptococci P. mirabilisviridans streptococci H. influenzae
M. catarrhalisNeisseria sp.
They are used to treat respiratory tract infections, urinary tract infections, and soft-tissue infections.
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Third Generation CephalosporinsSpectrum of Activity
• In general, are even less active againstgram-positive aerobes, but have greateractivity against gram-negative aerobes
• Ceftriaxone and cefotaxime have the bestactivity against gram-positive aerobes,including pen-resistant S. pneumoniae
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Third Generation CephalosporinsSpectrum of Activity
Gram-negative aerobes:E. coli, K. pneumoniae, Pr. mirabilis, H. influenzae, Mor. catarrhalis, N. gonorrhoeae (including beta-lactamase producing); N. meningitides. Pseudomonas aeruginosa (ceftazidime and cefoperazone)They are used for serious pediatric infections, including meningitis and sepsis
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Fourth Generation Cephalosporins• 4th generation cephalosporins for 2 reasons:Extended spectrum of activity
gram-positives: similar to ceftriaxone gram-negatives: similar to ceftazidime, including
Pseudomonas aeruginosa; also covers beta-lactamase producing Enterobacter sp.
Stability against β-lactamases; poor inducer of extended-spectrum β -lactamases
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Carbapenems(Imipenem, Meropenem)
• Most broad spectrum of activity of all antimicrobials
• Have activity against gram-positive and gram-negative aerobes and anaerobes
• Bacteria not covered by carbapenems include MRSA, VRE, coagulase-negative staph, C. difficile, Nocardia
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• The 1st carbapenem approved for clinical use was imipenem-cilastatin, which has a propensity to cause seizures in children, particularly in the setting of meningitis, and therefore meropenem is more suitable for pediatric use.
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MonobactamsSpectrum of Activity
Aztreonam bind preferentially to PBP 3 of gram-negative aerobes; has little to no activity against gram-positives or anaerobesGram-negativeE. coli, K. pneumoniae, P. mirabilis, S. marcescensH. influenzae, M. catarrhalisEnterobacter, Citrobacter, Providencia, MorganellaSalmonella, ShigellaPseudomonas aeruginosa
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Fluoroquinolones • Novel group of synthetic antibiotics
developed in response to growing resistance• The fluor inated quinolones (FQs) represent
a major therapeutic advance: Broad spectrum of activity Excellent bioavailability, tissue penetration,
prolonged half-lives Overall safety
• Disadvantages: resistance, expense
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The Available FQsOlder FQs• Norfloxacin (Noroxin®) - PO• Ciprofloxacin (Cipro®) – PO, IVNewer FQs• Levofloxacin (Tavanic®) – PO, IV• Gatifloxacin (Tequin®) – PO, IV
now discontinued• Moxifloxacin (Avelox®) – PO, IV
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FQs Spectrum of Activity
Gram-positive – newer FQs with enhanced potency
• Methicillin-susceptible Staphylococcus aureus• Streptococcus pneumoniae (including PRSP)• Group and viridans streptococci – limited
activity• Enterococcus sp. – limited activity
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FQs Spectrum of Activity
Gram-Negative – all FQs have excellent activity (cipro=levo>gati>moxi)• Enterobacteriaceae – including E. coli, Klebsiella
sp, Enterobacter sp, Proteus sp, Salmonella, Shigella, Serratia marcescens, etc.
• H. influenzae, M. catarrhalis, Neisseria sp.• Pseudomonas aeruginosa – significant resistance
has emerged; ciprofloxacin and levofloxacin with best activity
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FQs Spectrum of Activity
Atypical Bacteria – all FQs have excellent activity against atypical bacteria including:
• Legionella pneumophila - DOC• Chlamydia sp.• Mycoplasma sp.• Ureaplasma urealyticum
Other Bacteria – Mycobacterium tuberculosis, Bacillus anthracis
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FluoroquinolonesPharmacology
• Concentration-dependent bacterial killing • AbsorptionMost FQs have good bioavailability after oral
administration • DistributionExtensive tissue distribution –liver; lung; skin/soft
tissue and bone; urinary tract Minimal CSF penetration
• Elimination – renal and hepatic.
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FluoroquinolonesAdverse Effects
• Gastrointestinal – 5 % Nausea, vomiting, diarrhea, dyspepsia
• Central Nervous System Headache, agitation, insomnia, dizziness, rarely,
hallucinations and seizures (elderly)• Hepatotoxicity
LFT elevation (led to withdrawal of trovafloxacin) • Phototoxicity (uncommon with current FQs)
More common with older FQs (halogen at position 8)• Cardiac
Variable prolongation in QTc interval Led to withdrawal of grepafloxacin, sparfloxacin
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FluoroquinolonesAdverse Effects
• Articular Damage Arthopathy including articular cartilage damage,
arthralgias, and joint swelling Observed in toxicology studies in immature dogs Led to contraindication in pediatric patients and
pregnant or breastfeeding women Risk versus benefit Concerns of joint destruction in juvenile animals not
seen in humans• Other adverse reactions: tendon rupture,
dysglycemias, hypersensitivity
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Pearls - QuinolonesCiprofloxacin: Gram-negative
Oral and parenteral fluoroquinolone with best clinical and in vitro data for activity against pseudomonas. Experience is favorable and extensive for nosocomial pneumonia, osteomyelitis, neutropenic fever, travelers diarrhea and UTIs. Now approved for treatment of pediatr ic UTIs
Other fluoroquinolones: Gram-positive(i.e levofloxacin, gatifloxacin, moxifloxacin) have
enhanced gram positive activity and are preferred for infections due to S. pneumoniae.
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Dose
• Neonates: 10 mg/kg q 12 hr PO or IV.• Children: 15–30 mg/kg/24 hr divided q 12 hr
PO or IV; cystic fibrosis: 20–40 mg/kg/24 hr divided q 8–12 hr PO or IV.
• Adults: 250–750 mg q 12 hr; 200–400 mg IV q 12 hr PO (max dose: 1.5 g/24 hr
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Macrolides • Erythromycin is a naturally-occurring
macrolide derived from Streptomyceserythreus – problems with acid lability,narrow spectrum, poor GI intolerance, shortelimination half-life
• Structural derivatives include clarithromycinand azithromycin: Broader spectrum of activity Improved PK properties – better bioavailability,
better tissue penetration, prolonged half-lives Improved tolerability
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Macrolides
Mechanism of Action Inhibits protein synthesis by reversibly binding
to the 50S ribosomal subunit Suppression of RNA-dependent protein synthesis
Macrolides typically display bacteriostaticactivity, but may be bactericidal when present at high concentrations against very susceptible organisms
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Macrolide Spectrum of Activity
Gram-Positive Aerobes – erythromycin and clarithromycin display the best activity
(Clarithro>Erythro>Azithro)• Methicillin-susceptible Staphylococcus aureus• Streptococcus pneumoniae (only PSSP) – resistance is
developing• Group and viridans streptococci• Bacillus sp., Corynebacterium sp.
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Macrolide Spectrum of Activity
Gram-Negative Aerobes – newer macrolides with enhanced activity
(Azithro>Clarithro>Erythro)H. influenzae (not erythro), M. catarrhalis, Neisseria sp.DO NOT HAVE ACTIVITY AGAINST ANY ENTEROBACTERIACEAE
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Macrolide Spectrum of Activity
Anaerobes – activity against upper airway anaerobesAtypical Bacteria – all macrolides have excellent
activity against atypical bacteria including:• Legionella pneumophila • Chlamydia sp.• Mycoplasma sp.• Ureaplasma urealyticum
Other Bacteria – Mycobacterium avium complex,Treponema pallidum, Campylobacter, Borrelia, Bordetella, Brucella. Pasteurella
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MacrolidesPharmacology
AbsorptionErythromycin – variable absorption (15-45%);
food may decrease the absorption • Base: destroyed by gastric acid; enteric coated• Esters and ester salts: more acid stable
Clarithromycin – acid stable and well-absorbed, 55% bioavailable regardless of presence of food
Azithromycin –acid stable; 38% bioavailable; food decreases absorption of capsules
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MacrolidesPharmacology
Distribution Extensive tissue and cellular distribution – clarithromycin
and azithromycin with extensive penetration Minimal CSF penetration
Elimination Clarithromycin is the only macrolide partially eliminated by
the kidney (18% of parent and all metabolites); requires dose adjustment when CrCl < 30 ml/min
Hepatically eliminated: ALL NONE of the macrolides are removed during hemodialysis! Variable elimination half-lives (1.4 hours for erythro; 3 to 7
hours for clarithro; 68 hours for azithro)
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MacrolidesAdverse Effects
• Gastrointestinal – up to 33 %Nausea, vomiting, diarrhea, dyspepsiaMost common with erythro; less with new agents
• Cholestatic hepatitis - rare > 1 to 2 weeks of erythromycin estolate
• Thrombophlebitis – IV Erythro and AzithroDilution of dose; slow administration
• Other: ototoxicity (high dose erythro in patients with RI); QTc prolongation; allergy
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MacrolidesDrug Interactions
Erythromycin and Clarithromycin ONLY–are inhibitors of cytochrome p450 systemin the liver; may increase concentrationsof:
Theophylline Digoxin,Carbamazepine Valproic acidCyclosporine Terfenadine, AstemizolePhenytoin WarfarinErgot alkaloids
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AminoglycosidesMechanism of Action
• Multifactorial, but ultimately involvesinhibition of protein synthesis
• Irreversibly bind to 30S ribosomes– must bind to and diffuse through outer
membrane and cytoplasmic membrane and bindto the ribosome
– disrupt the initiation of protein synthesis,decreases overall protein synthesis, and producesmisreading of mRNA
• Are bactericidal
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AminoglycosidesSpectrum of Activity
Gram-Positive Aerobesmost S. aureus and coagulase-negative staphviridans streptococci Enterococcus sp.
Gram-Negative Aerobes (not streptomycin)E. coli, K. pneumoniae, Proteus sp.Acinetobacter, Citrobacter, Enterobacter sp.Morganella, Providencia, Serratia, Salmonella, ShigellaPseudomonas aeruginosa (amik>tobra>gent)
Mycobacteria– tuberculosis - streptomycin– atypical - streptomycin or amikacin
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AminoglycosidesPharmacology
• Absorption - poorly absorbed from GI tract• Distribution
– primarily in extracellular fluid volume; are widelydistributed into body fluids but NOT the CSF
• Elimination– eliminated unchanged by the kidney via glomerular
filtration; 85-95% of dose– elimination half-life dependent on renal function
normal renal function - 2.5 to 4 hours impaired renal function - prolonged
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AminoglycosidesAdverse Effects
Nephrotoxicity– nonoliguric azotemia due to proximal tubule damage;
increase in BUN and serum Cr; reversible if caughtearly
– risk factors: long duration of therapy (> 2 weeks),underlying renal dysfunction, elderly, othernephrotoxins
Ototoxicity– 8th cranial nerve damage - vestibular and auditory
toxicity; irreversible and saturable– vestibular: dizziness, vertigo, ataxia– auditory: tinnitus, decreased hearing– risk factors: same as for nephrotoxicity
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Sulfonamides• Spectrum includes: Staph, H. influenzae, Mor.
catarrhalis. Generally not effective vs. othermicrobes.
• Mechanism: acts on protein synthesis chain• Combined with erythromycin : it is as effective
as amoxcillin in treating AOM.• Sulfonamide + Trimethoprim is alternate 1st
line agent for AOM. Both drugs act on proteinchain—synergistic. Effective vs. beta-lactamase producing bacteria.
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VancomycinMechanism of Action
• Inhibits bacterial cell wall synthesis at a sitedifferent than beta-lactams
• Inhibits synthesis and assembly of thesecond stage of peptidoglycan polymers
• Bactericidal (except for Enterococcus)
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VancomycinSpectrum of Activity
Gram-positive bacteria– Methicillin-Susceptible AND Methicillin-Resistant S.
aureus and coagulase-negative staphylococci– Streptococcus pneumoniae (including PRSP), viridans
streptococcus, Group streptococcus– Enterococcus sp.– Corynebacterium, Bacillus. Listeria, Actinomyces– Clostridium sp. (including C. difficile), Peptococcus,
Peptostreptococcus
No activity against gram-negative aerobes or anaerobes
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VancomycinPharmacology
• Absorption– absorption from GI tract is negligible after oral
administration except in patients with intense colitis– Use IV therapy for treatment of systemic infection
• Distribution– widely distributed into body tissues and fluids, including
adipose tissue.– inconsistent penetration into CSF, even with inflamed
meninges• Elimination
– primarily eliminated unchanged by the kidney viaglomerular filtration
– elimination half-life depends on renal function
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VancomycinClinical Uses
• Infections due to methicillin-resistant staphincluding bacteremia, empyema, endocarditis,peritonitis, pneumonia, skin and soft tissueinfections, osteomyelitis
• Serious gram-positive infections in β-lactamallergic patients
• Infections caused by multidrug resistant bacteria.• Endocarditis or surgical prophylaxis in select
cases.• Oral vancomycin for refractory C. difficile colitis.
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***DOSE:• Children: 45–60 mg/kg/24 hr divided q
8–12 hr IV;• Clostridium difficile-associated colitis;
40–50 mg/kg/24 hr divided q 6–8 hr PO.• Adults: 0.5–1 g IV q 12 hr IV.
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S. aureus
Penicillin
[1950s]Penicillin-resistant
S. aureus
Evolution of Drug Resistance in S. aureus
Methicillin
[1970s]Methicillin-resistantS. aureus (MRSA)
Vancomycin-resistantenterococci (VRE)
Vancomycin
[1990s]
[1997]
Vancomycinintermediate-
resistantS. aureus(VISA)
[ 2002 ]Vancomycin-resistantS. aureus
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VancomycinAdverse Effects
Red-Man Syndrome – flushing, pruritus, erythematous rash on
face and upper torso– related to RATE of intravenous infusion;
should be infused over at least 60 minutes– resolves spontaneously after
discontinuation– may lengthen infusion (over 2 to 3 hours) or
pretreat with antihistamines in some cases
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VancomycinAdverse Effects
• Nephrotoxicity and Ototoxicity– rare with monotherapy, more common when
administered with other nephro- or ototoxins– risk factors include renal impairment, prolonged
therapy, high doses, ? high serumconcentrations, other toxic meds
• Dermatologic - rash• Hematologic - neutropenia and
thrombocytopenia with prolonged therapy• Thrombophlebitis
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Oxazolidinones
• Linezolid (Zyvox®) is the first availableagent which received FDA approval inApril 2000; available PO and IV
• Developed in response to need for agentswith activity against resistant gram-positives (MRSA, VRE)
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LinezolidMechanism of Action• Binds to the 50S ribosomal subunit near to
surface interface of 30S subunit – causes inhibition of 70S initiation complex which inhibits protein synthesis
• Bacteriostatic (cidal against some bacteria)
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Linezolid Spectrum of Activity
Gram-Positive Bacteria– Methicillin-Susceptible, Methicillin-Resistant AND
Vancomycin-Resistant Staph aureus and coagulase-negative staphylococci
– Streptococcus pneumoniae (including PRSP), viridans streptococcus, Group streptococcus
– Enterococcus faecium AND faecalis (including VRE)– Bacillus. Listeria, Clostridium sp. (except C. difficile),
Peptostreptococcus, P. acnesGram-Negative Aerobes – relatively inactiveAtypical Bacteria
– Mycoplasma, Chlamydia, Legionella
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Linezolid Pharmacology
• Concentration-independent bactericidalactivity
• Absorption – 100% bioavailable• Distribution – readily distributes into well-
perfused tissue; CSF penetration ≈ 70%• Elimination – both renally and nonrenally,
but primarily metabolized; t½ is 4.4 to 5.4hours; no adjustment for RI; not removed byHD
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Linezolid Adverse Effects
• Gastrointestinal – nausea, vomiting, diarrhea (6 to 8 %)
• Headache – 6.5%• Thrombocytopenia – 2 to 4%
– Most often with treatment durations of > 2 weeks
– Therapy should be discontinued – platelet counts will return to normal
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Clindamycin
Mechanism of Action Inhibits protein synthesis by binding
exclusively to the 50S ribosomal subunit Binds in close proximity to macrolides –
competitive inhibitionClindamycin typically displays bacteriostatic
activity, but may be bactericidal when present at high concentrations against very susceptible organisms
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ClindamycinSpectrum of Activity
Gram-Positive Aerobes
• Methicillin-susceptible Staphylococcus aureus (MSSA only)
• Streptococcus pneumoniae (only PSSP) –resistance is developing
• Group and viridans streptococci
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ClindamycinSpectrum of Activity
AnaerobesPeptostreptococcus some Bacteroides spActinomyces Prevotella sp.Propionibacterium FusobacteriumClostridium sp. (not C. difficile)
Other Bacteria – Toxoplasmosis gondii, Malaria
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ClindamycinPharmacology
Absorption – available IV and PO Rapidly and completely absorbed (90%); food with
minimal effect on absorptionDistribution Good serum concentrations with PO or IV Good tissue penetration including bone; minimal CSF
penetration Elimination Clindamycin primarily metabolized by the liver; half-
life is 2.5 to 3 hours Clindamycin is NOT removed during hemodialysis
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ClindamycinAdverse Effects
• Gastrointestinal – 3 to 4 %Nausea, vomiting, diarrhea, dyspepsia
• C. difficile colitis – one of worst offendersMild to severe diarrheaRequires treatment with metronidazole
• Hepatotoxicity - rareElevated transaminases
• Allergy - rare
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Agents for Infections Due to Gram Positive Bacter iaSt
aph.
epi
derm
idis
MR
SA
Stap
h. a
ureu
s
Stre
ptoc
occi
(Gro
up A
and
Gro
up B
)
GN
R
RG
NR
Pseu
dom
onas
aer
ugin
osa
Penicillin G
Penicillin VAnti staph penicillin: Methicillin, Oxacillin, Nafcillin
Dicloxacillin, Cloxacillin, CloxacillinVancomycin
Linezolid
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Broad and Extended Spectrum PenicillinsSt
aph.
epi
derm
idis
MR
SA
Stap
h. a
ureu
s
Stre
ptoc
occi
(Gro
up A
and
Gro
up B
)
GN
RG
N
Pseu
dom
onas
aer
ugin
osa
AmpicillinAmoxicillin
Carbenicillin, Mezlocillin, Piperacillin, Ticarcillin
Ticarcillin + Clavulanic Acid = Timentin ®, Piperacillin + Tazobactam = Tazosyn®
Ampicillin + Sulbactam = Unasyn®
Amoxicillin + Clavulanic Acid = Augmentin®
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Cephalospor insSt
aph.
epi
derm
idis
MR
SA
Stap
h. a
ureu
s
Stre
ptoc
occi
(Gro
up A
and
Gro
up B
)
GN
R
RG
NR
Pseu
dom
onas
aer
ugin
osa
CefazolinCephalexin, Cefadroxil
Cefepime
Cefuroxime, CefoxitinCefaclor, Loracarbef, Ceftibuten
Cefprozil, Cefuroxime axetil, Cefpodoxime,
Ceftriaxone, Cefotaxime
Cefdinir CefiximeCefoperazone & Ceftazidime
1st Generation
2nd Generation
3rd Generation
4th Generation
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Macrolides, Azalides and KetolidesSt
aph.
epi
derm
idis
MR
SA
Stap
h. a
ureu
s
Stre
ptoc
occi
(Gro
up A
and
Gro
up B
)
GN
R
RG
NR
Pseu
dom
onas
aer
ugin
osa
Erythromycin
Clarithromycin, Azithromycin, Telithromycin
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Broad Spectrum AntibioticsSt
aph.
epi
derm
idis
MR
SA
Stap
h. a
ureu
s
Stre
ptoc
occi
(Gro
up A
and
Gro
up B
)
GN
R
RG
NR
Pseu
dom
onas
aer
ugin
osa
Ciprofloxacin, Levofloxacin, Moxifloxacin, Gatifloxacin
Tetracycline, Doxycycline, Minocycline
Gentamicin, Tobramycin, Netilmicin, Amikacin
Imipenem, Meropenem
Trimethoprim/Sulfamethoxazole
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