Micro 13 - Cephalosporins Flashcards Preview

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Flashcards in Micro 13 - Cephalosporins Deck (22):
1

What happens as we increase in generation of cephalosporin?

There is an increase in G(-) coverage but decrease G(+) slightly as well.

2

What are the two big 1st generation cephalosporins and what do they cover?

Cefazolin and Cephalexin. They cover G(+) cocci but some G(-) as well.[PEcK] Proteus mirabilis, E.coli, Klebsiella.

3

What are the clinical uses of 1st generation of cephalosporins?

UTIs, URIs (sometimes), can be used for prophylaxis for viridans strep endocarditis (before dental procedures in patients with mechanical valves But amoxicillin is used first line).

4

What are the four big 2nd generation cephalosporins and what do they cover?

Cefoxitin, Cefaclor, Cefuroxime, Cefprozil. [HENS PEcK]: Haemophilus influenzae, Enterobacter, Neisseria, Serratia marcescens, Proteus mirabilis, E.coli, Klebsiella. Although Neisseria is on the list, we don't use it for gonorrhea anymore due to increased resistance.

5

What are the four big 3rd generation cephalosporins and what do they cover?

Ceftriaxone, Cefotaxime, Ceftazidime, Cefdinir. For serious G(-) infection. [HENS PEcKS]: Haemophilus influenzae, Enterobacter, Neisseria, Serratia, Proteus mirabilis, E.coli, Klebsiella, Streptococcus pneumoniae.

6

Which of the 3rd generation cephalosporins has the longest half life and how is it given?

Ceftriaxone. Given IV or IM once or twice daily. Treatment of choice for Neisseria gonorrhoeae.

7

How is Ceftriazone excreted? How do we use this to our advantage?

Excreted in bile, so it is great for patients that have renal failure.

8

What is a good 3rd generation cephalosporin that covers Pseudomonas infection?

Ceftazidime.

9

What is Cefdinir used for?

Resistant cases of otitis media.

10

What is the one big 4th generation cephalosporin and what is it used for?

Cefepime. It is a broad spectrum (breaks the rule of decreasing G(+) coverage) and is very good against pseudomonas.

11

Lewis Note: what generation does each cephalosporin belong to? Ceftazidime, cefepime, cephalexin, Cefuroxime, Cefotaxime, Cefaclor, Cefazolin, Cefdinir, Cefoxitin, Ceftriaxone.

1st: Cephalexin, Cefazolin. 2nd: Cefuroxime, Cefaclor, Cefprozil, Cefoxitin. 3rd: Ceftazidime, Cefotaxime, Cefdinir, Ceftriazone. 4th: Cefepime.

12

What are the bacterias that cephalosporins are NOT very good at covering?

[LAME]: Listeria, Atypicals (for atypical pneumonia like Mycoplasma, Chlamydia), Mrsa, Enterococci.

13

To which other class of antibiotics can cephalosporins have a cross-reactivity to?

There is 5-10% cross-reactivity with penicillins.

14

To which other class of antibiotics can cephalosporins have an increase nephrotoxicity?

Only if used with aminoglycosides (gentamicin).

15

Which generation of cephalosporin would you use for UTI prevention?

1st or 2nd generation.

16

Which generation of cephalosporin would you use for Serratia UTI?

2nd Generation.

17

Which generation of cephalosporin would you use for N.meningitidis?

3rd generation.

18

Which generation of cephalosporin would you use for Pseudomonas?

3rd (Ceftazidine) or 4th generation (cefepime).

19

Which generation of cephalosporin would you use for Otitis media due to nontypable H.influenzae?

2nd generation.

20

What side effect would you be concerned about if a patient is receiving both ceftriazone and gentamicin?

Nephrotoxicity.

21

What 1st generation drug is used for surgical prophylaxis, especially in orthopedic surgeries?

Cefazolin.

22

What is the mechanism of action of cephalosporins?

They are bacteriocidal beta-lactams that inhibit cell wall synthesis. Unlike penicillins, they are less susceptible to penicillinases.