Intro to ABX (Clinical Pearls) - Block 1 Flashcards
Penicillin MOA
Inhibits the cross-linking of peptidoglycan in cell wall, causing autolysis & cell death
Types of penicillins?
- Natural
- ANti-staph
- AMinopenicillins
- Aminopenicillisn + BLI
- Extend spec + BLIs
Natural penicillins?
Penicillin G and V
Pen G benzathine
Natural penicillin indication?
- Pharyngitis
- Syphillis
BBW of penicillins?
Pen G benzathine should not be given IV -> fatal
What is Pen G benzathine specifically used for?
Bicillin LA -> drug ofchoice for syphillis
Types of anti-staph pens?
- Nafcillin
- Oxacillin
- Dicloxacillin
Indications for anti-staph pens?
MSSA: ABX are therapeutically interchangeable
Because of the short half-life and frequent dosing what do you need to consider about anti-staphs?
Increased risk for phlebitis -> consider using 1st gen cephs for better tolerability
CP of anti-staphs?
- Metabolized by liver -> no renal dose adj
- Consider sodium content in CHF on Na restriction
- ABXs are interchangeable for MSSA
Types of aminopenicillins?
- Amoxicillin
- Ampicillin
Indications for aminopenicillins?
- URTIs
- Otisi media
- Strep throat
- H. pylori
- enterococci
CP of aminopenicillins?
- Diarrheas as PO
- Amoxicillin»_space; ampicillin
- Alternative for UTIs in pregnant women
When would ampicillin be considered over amoxicillin?
Suspectible enterococci infections
* E. faecalis = S
* E. faecium = R
Types of Aminopenicillins + Beta-Lactamase Inhibitors?
Amoxicillin/clavulanate (PO)
Ampicillin/sulbactam (IV)
Indication for Aminopenicillins + Beta-Lactamase Inhibitors?
- URTIs
- LRTIs
- Animal and human bites
CP for Augmentin?
Causes diarrhea -> take with food
Do Beta-lactamase inhibitors cause complete inactivation of all BL enzymes?
No
CP of ampicillin/sulbactam?
active against Acinetobacter baumannii associated with nosocomial infections
Types of extended spec + BLI?
Zosyn
Indication for ZOsyn?
- Empiric coverage of nosocomial infections
- Susceptible P. aeruginosa infection
CP of Zosyn?
- Broad spec activity against G- and G+ anaerobes
- COnsider sodium content in BHF on Na restriction
ADRs of penicillins?
Hypersensitivity
C. diff colitis
Monitoring parametrs of penicillins?
Hypersensitivity reactions
Cephalosporins MOA?
Inhibits the cross-linking of peptidoglycan in cell wall, causing autolysis & cell death
Types of 1st gen cephalosporins?
- Cefazolin
- Cephalexin
- Cefadroxil
Indication of 1st gen cephs
- SSTI
- surigical prophylaxis
- MSSA bacteremia and endocarditis
CP of 1st gen cephs?
- Alt agent for anti-staph
- Cephalexin and cefadroxil -> high cross reactivity to beta-lactams
- Ceffazolin: low cross reactivity to beta-lactams
Types of 2nd gen cephs?
- Cefuroxime
- Ceprozil
- Cefoxitin
- Cefotetan
Indication for 2nd gen ceph?
- URTIs
- CAP
- Surgical prophylaxis (Cefoxitin and cefotetan)
How does 2nd gen compare to 1st gen?
Less strep and staph activity
2nds gen cephs that have anaerobic coverage?
Cefoxitin and cefotetan
ADR of cefotetan?
MTT side chain -> inhibits Vit K production and causes prolonged bleeding
Which 2nd gen has a high cross reactivity with beta lactams
Cefprozil
Types of 3rd gen cephs?
- Cefdinir
- Cefpodoxime
- Cefotaxime
- Ceftriaxone
- Seftazidime
Indication for 3rd gen?
- URTIs
- LRTIs
- gonorrhea
- SSTIs
- Bacteremia
- Osteomylitis
- Menigitis and Lyme (ceftriaxone)
- Nosocomial and febrile neuropenia (Ceftazidime)
ADR of 3rd gen?
- C. diff infection
- Increased risk of GNR resistance
- Cefpodoxime -> MMT side chain inhibits Vit K production -> prolonged bleeding
How does ceftazidime coverage differ from other 3rd gens?
Only has Pseudomonas activity, poor strep and staph coverage
rd gens that are used for CNS infection?
- Ceftriaxone (meningitis and Lyme)
- Cefotaxime
- Ceftazidime (febrile neutropenia)
Ceftriaxone
Dosing, DDI, ADR, CI
Dosing: QD, menigitis BID
* No renal adjustment
DDI: intercts with calcium-containing meds (forms crystals in lungs and kidneys)
ADR: biliary sludging -> hyperbilirubemia
CI: Neonates (cefotaxime is safer)
Types of forth gen cephs?
Cefepime
Indication cefepime?
- Empiric therapy for nosocomial infection
- Febrile neutropenia
- Intra ab infction
- SSTIs
- UTI
Pseudomonas activity (permanent charge)
Caution with cefepim?
- Neurotoxicity
- Renal dose adjustment
Types of 5th gen cephs?
Ceftaroline
Indication of ceftaroline?
- CAP
- MRSA
- Complicating SSRI
ADR of ceftaroline?
Neutropenia
Types of sideophor ceph? MOA
Cefiderocol (Fetroja): contains a sideophore side chain that allows it to be taken up into the abcteria bypassing resistance mechanisms
Indication for Cefiderocol?
- Complicated UTI
- HAP
- P. aeruginosa, ESBL- and carbapenemase producing organisms)
- Only used in patients with resistance of common ABX for the inidcation
Types of Cephalosporin + Beta-Lactamase Inhibitors?
ceftazidime/avibactam (IV), ceftolozane/tazobactam (IV), cefepime/enmetazobactam (IV)
Indication for Cephs + BLI?
- MDR P. aeruginosa
- ESBL-producign organsims
- ONLY in patients with bacterial infections which are resistant to other commonly-used antibiotics for the indication
What ceph combo has activity against carbapenem resistant enterobacterales?
Ceftazidime/avibactam
What can be added to ceph +BLI therapies if resistance is observed?
Metronidazole
ADR of Cephs?
- Hypersensitivity rx
- C diff colitis
Monitoring parameters of cephs?
- Hypersensitivity rx
- Renal function
MOA of carbapenems?
Inhibits the cross-linking of peptidoglycan in cell wall, causing autolysis & cell death
Types of cabapenems?
- Imipenem/cilastatin
- Meropenem
- Ertapenem
Indications for carbapenems?
- Nosocomial
- Febrile neutropeia
- Intra ab infection
- ESBL infections
ABX with the broadest spec? Caution?
Imipenem/cilastatin and meropenum -> should not be used as empiric therapy for CA infections
ADRs of imipenem/cilastatin?
Seizures
* Renal adjustment to minimize sz
DDI with carbapenems?
Valproic acid
* carbapenems induce VPA -> sub therapeutic VA [C] and breakthrough sz
How does ertapenen differ from other carbapenems?
- QD (more convenient)
- Weaker spec
* Pooractivity against Pseudmonas, acinetobacter, enterococci
Types of Carbapenems + Beta-Lactamase Inhibitors?
imipenem/cilastatin/relebactam (IV)
meropenem/vaborbactam (IV)
Indication for carbapenems + BLI?
- Complicated UTI
- Intra ab infection
- HAP
- VAP
ADR of carbapenems?
- Hypersensitvity
- C diff colitis
CP of carbapenems + BLI?
- Activity against carbapenemase-producing Enterobacterales and ESBL
- Imipenem/cilastatin/relebactam has . carbapenem-resistant Pseudomonas coverage
- Vaborbactam has no CR-pseudomonas coverage
Monitoring paratmeters of carbapenems?
- Hypersensitivity rx
- Renal function
Cautions when using carbapenems?
SZ higher in elderly with hx of sz or renal dysfunction
MOA of monobactams?
Inhibits the cross-linking of peptidoglycan in cell wall, causing autolysis & cell death
Types of monobactams?
Aztreonam
Indication for manobactams?
- G- infections including Pseudomonas (especially hx of beta-lactam allergy)
ADR of monobactams?
C diff colitis
Anaphylactic penicillin allergy
Avoid if patient has a ceftazidime allergy
Monitoring parameters of aztreonam?
Renal function
Macrolides MOA?
Binds to 50S subuntis on bac ribosome -> inhibits it from adding new aa to elongate protein chain
Types of macrolides?
- Azithromycin
- Clarithromycin
- Erythromycin
Indication of macrolides?
- RIs
- Atypical infection
- Travelers diarrhea (Azitrhomycin)
- H pylori PUD (clarithromycin)
- CAP butnot as a monotherapy due to increasing resistance
DDI of Macrolides?
Not Azithromycin: potent CYP3A4 inhibits
ADRs of macrolides?
- GI intolerance
- Diarrhea (Erythromycin -> prokinetic and GI stimulating)
- QTc prolongation
MOA of fluroquinolones?
Inhibits DNA topoisomerase -> DNA breakage and cell death
Types of fluroquinolones?
- Ciprofloxacin
- Levofloxacin
- Moxifloxacin
- Delafloxacin
Quinolones indicated for MRSA?
Delafloxacin
Quinolone not for respiratory?
Ciprofloxacin: poor S. pneumoniae coverage)
What is not an indication for moxifloxacin?
UTI -> poor urinary concntration
All quinolones reque renal adjustment?
Except for moxifloxacin
CI of quinolones?
Pregnancy and children -> imparied bone and cartilage development
BBW of quinolones?
- Tendon rupture
- Peripheral neuropathy
- CNS effect
- Myasthenia gravis