Penicillins

Question 1

Natural (eg Penicillin)

Answer 1

Some GPC, GPR, GNC, most anaerobes (except Bacteroides)

Group A Strep, Enterococcus, Listeria, Pasteurella, Actinomyces, Syphilis

Question 2

Anti-Staph (eg Nafcillin)

Answer 2

Active vs. PCNase-producing Staph; little activity vs. Gram (-)

Staphylococcus (except MRSA)
Streptococcus

Question 3

Amino (eg, ampicillin)

Answer 3

Penetrate porin channel of gram-negative
Not stable against penicillinases

Escherichia coli, Proteus, H. influenzae, salmonella, Shigella, enterococci, Listeria

Question 4

Extended (eg piperacillin)

Answer 4

Penetrate porin channel of gram-negative
More resistant to penicillinases

most gram-negative rods including Enterobacter, Pseudomonas, Serratia

Question 5

Carbapenems (eg imipenem)

Answer 5

Resistant to most beta-lactamases

most gram-positive and gram-negative, including anaerobes; not MRSA or VRE

Question 6

Monobactams (eg aztreonam)

Answer 6

Active versus gram (-) but not gram (+)

gram-negative bacterial infection in patient with penicillin or cephalosporin allergy

Question 7

Beta-lactamase inhibitor (eg sulbactam)

Answer 7

Inhibit plasma mediated beta-lactamases

adds Staph, B. fragilis and some gram-negative rods (H. influenzae, M. catarrhalis, some Klebsiella); intrinsic activity against Acinetobacter (sulbactam only)