Cell-Wall Inhibitors
How do beta lactams inhibit cell wall synthesis?
Bind to PCN-binding protein (PBP), preventing cross links and degrading cell wall. This kills the bacteria (Bactericidal)
What are the types of protein synthesis inhibitors? Which ones act as anti-inflammatories?
Tetracyclines (AI), macrolides (AI), lincosamines (AI), aminoglycosides
Which Anti-DNA abx are DNA synthesis disruptors vs. DNA destroyers?
Destroyers: Nitroimidazoles
what antibiotic can cause colorblindness?
Ethambutol (anti-mycobacterium)
What is the uncommon but potentially severe adverse drug reaction to Anti-Folates?
SJS/TEN
What are the types of cell wall inhibitors?
Beta lactams: Penicillins, Cephalosporins, Monobactams, Carbapenems, Beta-lactamase inhibitors
Glycopeptides (Vancomycin)
What types of bacteria do tetracyclines cover?
Gram +, Gram -, Intracellular and mycoplasma organisms (Atypicals), no mycobacterium coverage.
what is the main risk of fluoroquinolones (Why we don't prescribe to children)?
Tendon rupture.
what antibiotic has drug interactions with alcohol?
nitroimidazoles
I have a back, you can sit on me, I sometimes have arms, but no hands. what am I?
Quadruple amputee
jk its a chair
What is the widest spectrum beta lactam antibiotic?
Carbapenem (most GNRs, GPCs. Used in inpatient settings)
what is the "bactericidal" group of protein synthesis inhibitor?
aminoglycosides
What antibiotic group is a potential carcinogen? Which one is used as cancer treatment?
Nitroimidazoles are potentially carcinogenic
Fluoroquinolones can be used as cancer treatments in high doses.
What are wanted and unwanted drug interactions of cell wall inhibitors?
Wanted:
-Probenacid delays excretion from kidney, increasing bioavailability
-Pairing a beta lactam with an aminoglycoside (bactericidal protein synthesis inhibitor) can increase the spectrum of activity.
Unwanted:
-Allopurinol with ampicillin/amoxicillin = rash
-Drugs influenced by gut microbiome (Warfarin, Estradiol)
-Bacteriostatic antibiotics will halt replication -> bactericidal antibiotics don't work
Which antibiotics attach to bivalent cations?
tetracyclines, nitroimidazoles
What is the only beta lactam that does not have any gram positive coverage?
monobactams
Would you expect high or low activity of a macrolide antibiotic in the stomach?
low activity. Increases activity in basic conditions.
what anti-DNA antibiotic covers oral anaerobes and MRSA?
Anti-folates
Which antibiotics inhibit CYP450 enzymes?
Tetracyclines, Macrolides, Isoniazid
how do lobsters communicate?
They squirt pee at each other - Rosette glands produce pheromones, which are then injected into the stream of urine (Lobsters urinate from their faces, the bladder is located just under their brain). The urine with the pheromones is ultimately released through openings just at the base of a lobster’s antennas. Fan-like appendages in the face of a lobster help direct the stream of urine directly towards other lobbies.
When concerning vancomycin, what are the main adverse drug reactions? How can we avoid these, when possible?
ADRs: The usuals (GI disturbance, Hypersensitivity, Opportunistic infxn), ototoxicity, nephrotoxicity, red man syndrome.
PO vancomycin is not absorbed into blood stream, and stays in gut, increasing bioavailability in gut. Also spares disseminating side effects. Good for GI infections eg. Cdiff.
Which protein synthesis inhibitors are excreted via bile? via kidney/urine?
Bile: Macrolides & Lincosamines
Kidney/urine: Tetracyclines & aminoglycosides
a patient presents with hyperkalemia and hypoglycemia, and you find out they have been taking an antibiotic for the past 2 weeks. what is the likely antibiotic and what is happening?
Anti-folates (SMX/TMP)
Sulfamethoxazole very similar to sulfonylureas, which stimulate insulin release --> hypoglycemia
Anti-folates decrease K+ excretion in urine --> hyperkalemia
What antibiotics cause QT prolongation?
macrolides, fluoroquinolones
a patient is on warfarin. do you need to monitor INR if you prescribe them an anti-folate antibiotic? a tetracycline? a macrolide? a beta lactam?