Antimicrobial Review (Schoney) Flashcards
What classes of antibiotics make up the Beta Lactams?
Penicillins
Extended spectrum penicillins
Cephalosporins
Carbapenems
What form of Penicillin is IV/IM? What form is PO?
Pencillin G is IV/IM
Penicillin VK is PO
What is the name for the long-acting IM version of penicillin?
Benzathine penicillin (Bicillin LA)
The natural penicillins are Penicillin G, Penicillin VK, and Benzathine Penicillin.
What are they commonly used to treat?
Strep pharyngitis/cellulitis.
Syphilis (Benzathine penicillin)
What are the aminopenicillins?
Ampicillin (IV) and Amoxicillin (PO)
What are the aminopenicillins commonly used to treat?
Pharyngitis, sinusitis, otitis media, endocarditis prophylaxis, lyme dz (age <8)
What are the anti-staphylococcal penicillins?
Nafcillin (IV) or dicloxacillin (PO)
What are the anti-staphylococcal penicillins commonly used for?
Skin and soft tissue infections with suspected staph, also works against strep.
What are the augmented penicillins?
Ampicillin/sulbactam (Unasyn) (IV), Amoxicillin/clavulanate (Augmentin) (PO), Piperacillin/tazobactam (Zosyn) (IV).
What are the augmented penicillins commonly used for?
Amp/sulbactam and Amox/clav: Bites, otitis media, sinusitis, AECB, dental infections, skin and soft tissue infections.
Pip/tazo - Broad spectrum with pseudomonas coverage, used for hospitalized patients.
What is the mechanism of action of penicillins?
Stops cell wall synthesis by binding pencillin binding protein.
What is the mechanism of resistance to penicillins?
B lactamases and PBP alterations
Are penicillins bacteriocidal or bacteristatic?
Bacteriocidal
Are penicillins excreted through the kidneys are metabolized by the liver?
Kidneys
What does the bacterial coverage for the cephalosporins look like?
1st generation has excellent gram + activity and poor gram - activity.
Gram + activity decreases as generations increase.
Gram - activity increases as generations increase.
Exception is next generation, which has broad coverage + MRSA coverage.
What is the mechanism of action of cephalosporins?
Stops cell wall synthesis by binding PBP
What is the mechanism of resistance for cephalosporins?
beta lactamases.
What adverse reaction is linked to ceftriaxone?
Biliary sludging and pseudocholelithiasis
What are the first generation cephalosporins?
Cefazolin (Ancef) (IV)
Cephalexin (Keflex) (PO)
Do first generation cephalosporins cover MRSA or Pseudomonas?
Neither
What are first generation cephalosporins commonly used for?
Skin and soft tissue infections, strep pharyngitis, pre op prophylaxis (cefazolin), and uncomplicated cystitis.
What is a second generation cephalosporin?
Cefuroxime (Ceftin) (PO)
What is cefuroxime commonly used for?
Otitis media, sinusitis, AECB, skin and soft tissue infections.
What are the 3rd generation cephalosporins?
Ceftriaxone (Rocephin) (IM/IV)
Cefdinir (Omnicef) (PO)
What attribute of ceftriaxone makes it a great drug for meningitis?
It can cross the blood brain barrier.
Do 3rd gen cephalosporins treat MRSA or pseudomonas?
Neither
What are 3rd gen cephalosporins commonly used to treat?
CAP
Meningitis
Gonorrhea (Plus azithromycin)
Pyelonephritis
What is a 4th generation cephalosporin?
Cefepime (IV)
Do 4th gen cephalosporins treat MRSA or pseudomonas?
Yes, pseudomonas
No for MRSA.
What is a next generation (5th generation) cephalosporin?
Ceftaroline (Teflaro) (IV)
Do next generation cephalosporins cover MRSA or pseudomonas?
Yes - MRSA
What are the antibiotics is the tetracyclines class?
Tetracycline, minocycline, doxycycline
What is the mechanism of action for tetracyclines?
Protein synthesis inhibition at 30 S bacterial ribosomes.
What is the mechanism of resistance to tetracyclines?
Efflux pump
Are tetracyclines excreted by the kidneys or liver?
Split
Are tetracyclines bacteriocidal or bacteriostatic?
Bacteriostatic
What populations are tetracyclines contraindicated in?
Pregnant patients
Kids <8 years of age
What is an adverse reaction to tetracyclines you should know about?
Photosensitivity
What are tetracyclines commonly used to treat?
Sinusitis AECB CAP Non-gonococcal urethritis/cervicitis TICK BORNE disease
What medication should you be sure to not combine with tetracyclines?
Isotretinoin
What can the combination of tetracyclines and isotretinoin cause?
Pseudotumor cerebri
What medication are the macrolides?
Azithromycin, clarithromycin, erythromycin
What is the mechanism of action for macrolides?
Protein synthesis inhibition at 50 S ribosome
What is the mechanism of resistance to macrolides?
Ribosomal changes and efflux pump
Are macrolides bacteriostatic or bacteriocidal?
Bacteriostatic
What are macrolides commonly used for?
Pharyngitis, otitis media, CAP/atypical PNA, whooping cough (pertussis), Urethritis and cervicitis, and H. plyori.
What macrolide is a potent CTPA4 inhibitor?
Caution with warfarin
Clarithromycin
What macrolide is a potent CTPA4 inhibitor?
Caution with warfarin
Clarithromycin
What macrolide has a black box warning for QTC prolongation?
Azithromycin
What macrolide is a promotility agent?
Erythromycin
What macrolide is associated with a metallic taste?
Clarithromycin
Name 1 medication from the lincosamide class.
Clindamycin (IV or PO)
What is the mechanism of action of clindamycin?
Protein synthesis inhibition at 50 S ribosome.
What is the mechanism of resistance to lincosamides?
Ribosomal modification
Are lincosamides bacteriocidal or bacteriostatic?
Bacteriostatic.
Lincosamides are notorious for causing what GI infection?
C diff
What are lincosamides commonly used to treat?
Substitution for b lactam allergy for skin and soft tissue infections and strep pharyngitis.
Anaerobic infections/abscesses.
Dental infections
What medications make up the fluoroquinolone class?
Which are respiratory and which are non-respiratory?
Ciprofloxacin (PO, IV, drops) - non-respiratory.
Levofloxacin (PO
What is the mechanism of action of fluoroquinolones?
Inhibit bacterial DNA toposiomerases
What is the mechanism of resistance to fluoroquinolones?
Alteration in DNA topoisomerase
Are fluoroquinolones excreted by the kidneys or liver?
Split
Are fluoroquinolones bacteriocidal or bacteriostatic?
Bacteriocidal
What is ciprofloxacin commonly used for?
Complicated UTI (pyelonephritis, prostatitis)
Enteric infections/traveler’s diarrhea
Diverticulitis (plus metronidazole)
What are respiratory fluoroquinolones (levofloxacin, moxifloxacin) commonly used for?
CAP
Pelvic infections
There are many adverse reactions associated with fluoroquinolones. Name some.
Arthropathy Tendinopathy CNS toxicity Photosensitivity QT prolongation Dysglycemia Neuropathy
What medications are the sulfonamides?
Trimethoprim/sufamethoxazole (Batrim or Septra) (IV or PO)
Do fluoroquinolones cover MRSA or psuedomonas?
Pseudomonas
Do the sulfonamides cover MRSA or pseudomonas?
MRSA
What is the mechanism of action for sulfonamides?
Inhibition of folate synthesis
Mechanism of resistance to sulfonamides?
Alteration in folate synthesis.
Decreased binding sites.
A patient taking warfarin recently started bactrim. How do you expect their INR to change?
Increase
Sulfonamides inhibit CYP2C9.
Are sulfonamides excreted by the kidneys or liver?
Kidneys
Are sulfonamides bacteriocidal or bacteriostatic?
Bacteriostatic.
What hematologic disorder is a contraindication to sulfonamides? Why?
G6PD deficiency
Hemolytic anemia
What are sulfonamides commonly used for?
PCP pneumonia and prophylaxis
UTI
MRSA and soft tissue infections
What are the nitromidazoles?
Metronidazole (Flagyl) (IV or PO)
Tinidazole (Tindamax) (PO)
What is the coverage for nitromidazoles?
Anaerobes below the diaphragm.
Protazoa.
Are nitromidazoles bacteriostatic or bacteriocidal?
Bacteriocidal
Are nitromidazoles excreted by the kidneys or liver?
Liver
What are nitromidazoles commonly used to treat?
Bacterial vaginosis, C diff, giardia, trichomoniasis, abdominopelvic infections
Name 3 adverse reactions to nitromidazoles.
Metallic taste
Disulfram reaction
Fetotoxic in 1st trimester
What are the aminoglycosides?
Gentamycin (IV), tobramycin (IV)`
Do aminoglycosides over MRSA or pseudomonas?
Pseudomonas
What is the mechanism of action for aminoglycosides?
Inhibit 30 S ribosome
What are the mechanisms of resistance to aminoglycosides?
Ribosomal modification and efflux mechanisms
Are aminoglycosides excreted by the liver or kidneys?
Kidneys
Are aminoglycosides bacteriocidal or bacteriostatic?
Bacteriocidal
Name 2 adverse reactions to aminoglycosides.
Nephrotoxicity
Ototoxicity
Name 1 medication from the glycopeptide class of antibiotics.
Vancomycin (IV and PO)
Does vancomycin cover pseudomonas or MRSA?
MRSA
What is the mechanism of action for vacomycin?
Inhibits cell wall synthesis
What is the mechanism of resistance to vancomycin?
Alteration in binding sites
Is vancomycin excreted through the kidneys or liver?
Kidneys
Why can’t C diff be treated with parenteral vancomycin?
No systemic absorption of PO formulation
Is vancomycin bacteriostatic or bacteriocidal?
Bacteriocidal for gram + only.
Vancomycin infusions should be given over 1 hour to prevent?
Red man syndrome
What medications make up the cabapenem class of antibiotics?
Imipenem, meropenem, ertapenem (all IV only)
Do carbapenems cover MRSA or pseudomonas?
Pseudomonas for Imipenem and meropenem.
NOT ERTAPENEM
Mechanism of action for carbapenems?
Stops cell wall synthesis
Mechanisms of resistance to carbapenems?
carbapenemases
Adverse reactions to carbapenems?
Seizures
Nephrotoxicity
What are carbapenems commonly used for?
Ventilator associated PNA
Resistant complicated UTI
Nosocomial infections
Name 4 antimycobacterials.
Isoniazid
Rifampin
Pyrazinamide
Ethambutol
What is the drug of choice for latent TB?
The PANCE answer, not the current answer
Isoniazid
What is the duration of therapy for latent TB treatment?
9 months
Adverse reactions to isoniazid?
Increased liver enzymes
Peripheral neuropathy
What antimycobacterial should be avoided with HIV meds?
Rifampin, because it is an inducer of CYP enzymes
What are 2 adverse reactions to rifampin?
Red lobster syndrome and elevated liver enzymes.
What antimycobacterial can cause color blindness?
Ethambutol
What medications make up the polyenes class of antifungals?
Amphotericin B
Nystatin
What is the most severe side effect to amphotericin B?
Nephrotoxicity
What topical medications are in the azoles class of antifungals?
Topical Skin: Clotrimazole (lotramin), miconazole
Topical vaginal: terconazole, miconazole (monistat), tioconazole
Topical oral: Clotrimazole (Mycelex), miconazole.
What systemic medications are in the azoles class of antifungals?
Ketoconazole Itraconazole Fluconazole Voriconazole Posaconazole
What is the only azole antifungal that can get into the bladder to treat fungal UTIs?
Fluconazole
Are azole antifungals excreted by the kidneys or liver?
Kidneys
What are azole antifungals commonly used for?
Candidal infections - vulvovaginitis, esophagitis
What medications are in the allylamines class of antifungals?
Tervinafine (Lamasil) (PO or topical)
What is terbinafine commonly used for?
Onychomycosis and cutaneous dermatophyte infections
What antibiotics are associated with nephrotoxicity?
Aminoglycosides (usually gentamicin)
Vancomycin
What antibiotics are associated with color findings?
Vancomycin -> red man syndrome
Rifampin -> red lobster syndrome
Discolored teeth -> tetracyclines
Yellow babies ->sulfonamides
What antibiotics cause complications in pregnancy?
FAST Fluoroquinolones (arthropathy) Aminoglycosides (CN8 toxicity in fetus) Sulfonamides (Newborn kernicterus) Tetracyclines (Tooth/bone problems in infant)
What are the mediators for each of the following types of hypersensitivity reactions? Type I Type II Type III Type IV
Type I - IgE mediated
Type II - IgG and complement mediated
Type III - Antibody/antigen complexes
Type IV - T cell mediated
Give an example reaction for each of the types of hypersensitivity reactions.
Type I - Urticaria or anaphylaxis
Type II - Bone marrow suppression
Type III - Serum sickness, PSGN
Type IV - Stevens Johnson, toxic epidermal necrolysis, organ rejection.