Cell Wall Inhibitors ABX med class- Quiz 2 Flashcards

Question

Carbapenems MOA Prototype Uses

Answer 1

-Synthetic ß-lactam antibiotics that differ from PCNs in that sulfur atom of one ring has been externalized and replaced by a carbon atom -Resists breakdown by ß-lactamases -Can be used empirically as it is active against gram + and gram – ßlactamase producing pathogens, anaerobes and Pseudomonas -Imipenem=PROTOTYPE drug -Ex: Imipenem, Meropenem,, Doripenem, Ertapenem -Mainly used in: Last-resort, used for serious, drug-resistant infections, particularly ESBL-producing and MDR Gram-negative bacteria.

Answer 2

-All carbapenems are given IV - Imipenem, Meropenem and Doripenem penetrate well into tissues, fluids and CSF [when meninges are inflamed] -Excreted by glomerular filtration, need to dose reduce in CKD -Because Imipenem is cleaved by a dehydropeptidase in the proximal tubule, it is combined with cilastin to protect the drug from this cleavage

Answer 3

-Nausea, Vomiting and Diarrhea can be seen with Imipenem -High levels of Imipenem can cause seizures [less chance with other carbapenems] -Because carbapenems and PCNs share a common core cross sensitivity may occur -Use carbapenems cautiously in those with PCN allergy (rate is <1%)

Answer 4

-Disrupt bacterial cell wall synthesis— unique because ß-lactam ring is not fused to another ring -Aztreonam mainly covers gram – bugs -Relatively non-toxic, but can cause phlebitis, rash and elevated LFTs -Safe drug used for those allergic to PCN, Cephalosporins, Carbapenems -Renal dosage -Aztreonam= PROTOTYPE -Mainly used in: -Treating serious Gram - infections, especially in patients allergic to penicillins or cephalosporins. -PNA, GYN, ABD, skin, Bacteremia

Answer 5

-Hydrolysis of the ß-lactam ring—destroys the antimicrobial effect -Clavulanic acid, Sulbactam and Tazobactam contain a ß-lactam ring, but alone have no antimicrobial effects or cause any SE -ß-lactamase inhibitors function by inactivating ßlactamases, and protect the antibiotics that are normal substrates for these enzymes -ß-lactamase inhibitors are combined with ß-lactamasesensitive antibiotics, such as Amoxicillin, Ampicillin and Piperacillin -Mainly used in: -Broad-spectrum therapy, esp when Pseudomonas, ESBL, or anaerobes are concerns.

Answer 6

-Ceftolozane + Tazobactam: IV medication used to treat resistant multi-drug resistant P. aeruginosa -Ceftazidime + Avibactam: -IV medication with broad gram – -Adding Avibactam allows the drug to resist hydrolysis against broad spectrum ß-lactamases -Both of these drugs are used to treat INTRA-ABDOMINAL INFECTIONS [with Metronidazole] and for management of COMPLICATED UTIs -Are reserved for the treatment of infections due to multiple-drug resistant pathogens

Answer 7

-Meropenem + Vaborbactam: -Approved for the treatment of complicated UTIs including PYELONEPHRITIS

Answer 8

-Tricyclic glycopeptide (bactricidal) -Active against: gram + pathogens—MRSA, MRSE, Enterococcus, C. Diff -Used in SKIN/SOFT TISSUE INFECTIONS, ENDOCARDITIS, PNA -Dosing frequency depends on GFR— monitoring creatinine clearance is needed to optimize exposure while minimizing toxicity -Best cure rates occur when trough is 10-20 mcg/mL (Initial trough levels are drawn before the 4th or 5th dose to ensure proper dosing) -ADEs: nephrotoxicity, infusion related reactions [“Red-Man” Syndrome and phlebitis], ototoxicity -Because resistance is now being seen—prudent use of the drug should take place

Answer 9

-"Vancin's" -Bactericidal concentration-dependent lipoglycopeptide drugs active against gram + pathogens -Spectrum is similar to Vancomycin— staphylococcus, streptococcus and enterococcus -Are MORE potent than Vanco and may cover VR isolates -Telavancin is an alternative to Vancomycin for acute bacterial skin infections, hospital acquired pneumonia from resistant gram + organisms, including MRSA -Use of Telavancin may be limited by ADEs: nephrotoxicity, risk of fetal harm, interactions with drugs that prolong the QTc, renal function and pregnancy test must the evaluated before prescribing this drug, infusion reaction -Ex. Telavancin, Oritavancin, Dalbavancin

Answer 10

-Bactericidal concentration-dependent lipopeptide antibiotic that is an alternative to other agents,(Vancomycin or Linezolid) to treat infections caused by resistant gram + organisms (MRSA and VRE) -Used to treat complicated SSSIs/ BACTEREMIA/ RIGHT SIDED ENDOCARDITIS -This drug is inactivated by pulmonary surfactants—so it cannot be used to treat pneumonia EVER -Given IV once a day -NOTE* Dapto is the only lipopeptide abx whos MOA is depolorization of cell membrane, inhibiting DNA/RNA synthesis as opposed to just inhibits bacterial wall synthesis*

Answer 11

-Is a synthetic derivative of phosphonic acid that blocks cell wall synthesis -Used for UTIs from E. coli or E. faecalis—is considered 1st line for ACUTE CYSITIS -Rapidly absorbed after oral ingestion -Excreted in active form in urine and maintains high levels for days— allowing for one time dosing -ADEs: diarrhea, vaginitis, nausea and headache

Answer 12

-Are cation polypeptides that bind to phospholipids on bacterias cell membranes on gram - bugs -Detergent like effects that disrupt cell membrane and cause cell death -Concentration dependent bactericidal agents -Polymyxin B= PROTOTYPE -Use of these drugs is limited due to renal and neurotoxicity [when used systemically] -With increasing gram – resistance, these agents are now used as SALVAGE AGENTS for multi-drug resistant infections (last ditch efforts)

Cell Wall Inhibitors ABX med class- Quiz 2 Flashcards

(36 cards)