L29- β-Lactams: carbapenems, monobactams

Question 1

list the cell wall synthesis inhibitors

Answer 1

β-lactams: penicillins, cephalosporins, carbapenems, monobactams

vancomycin
daptomycin
bacitracin

Question 2

list the β-lactams

Answer 2

penicillins
cephalosporins
carbapenems
monobactams

Question 3

list the carbapenems

Answer 3

doripenem
ertapenem
imipenem
meropenem

Question 4

Carbapenems are usefully resistant to (1) and therefore are effective against (2) bacteria species. They are inactive against (3) and (4) bacteria.

Answer 4

1- β-lactamases (mostly)
2- β-lactamase producing Gram+/- aerobes/anaerobes (broad-spectrum)

3- carbapenemase producing bacteria (carbapenem resistant enterobacteriaceae / klebsiella
4- MRSA

Question 5

Carbapenems are the drugs of choice for…. (explain general clinical uses also)

Answer 5

• extended spectrum β-lactamase producing Gram- bacteria —- life-threatening conditions where broad spectrum antibiotic is required
• carbapenem use is restricted to avoid resistance

Question 6

Carbapenem:

• (1) route of administration
• (2) is the only agent of this group that may form nephrotoxic metabolite, therefore it is combined with (3) which has (4) function

Answer 6

1- IV

2- imipenem
3- Cilastatin
4- dehydropeptidase I inhibitor –> prevents toxicity and inc availability

Question 7

Carbapenem AEs:

• (1) common AEs
• high levels of (2) agent may cause CNS toxicity, eg. (3)
• (4) in relation to penicillins

Answer 7

1- GI distress: n/v/d

2- imipenem
3- seizures

4- partial cross-reactivity: give in Pts with mild penicillin allergy (rash), avoid if allergy is severe (shock)

Question 8

list the monobactams

Answer 8

aztreonam

Question 9

describe the general clinical uses of monobactams

Answer 9

(aztreonam)
-aerobic Gram- infections in Pts allergic to penicillin
(resistant to β-lactamases)

Question 10

Monobactam Pharmacokinetics:

• (1) route of administration
• (2) route of elimination
• given via inhalation in (3) Pts
• penetrates (4) body cavity when inflamed

Answer 10

(aztreonam)
1- IV, IM
2- urine / kidneys

3- CF pts
4- CSF (only during meningitis –> Tx, but not prophylaxis)

Question 11

describe monobactam AEs

Answer 11

(aztreonam)

• mostly non-toxic
• occasional rash, GI upset

-some cross-reactivity with other β-lactams —-> mild allergy give, avoid if serious allergy