2 Introduction to antibiotic resistance

Question 1

Classification of beta-lactams

Answer 1

Penicillins
Cephalosporins
Carbapenems

Question 2

Classification of cephalosporins

Answer 2

5 generationer

Question 3

Hvad er 1. gen. cephalosporiner aktive mod?

Answer 3

HOVEDSAGELIGT G+

Gram-positive:Activity against penicillinase-producing staphylococci and streptococci. No activity against MRSA or enterococci.
Gram-negative:Activity against Proteus mirabilis, some Escherichia coli, and Klebsiella pneumoniae(PEcK) but no activity against Bacteroides fragilis, Pseudomonas, Acinetobacter, Enterobacteror Serratia

Question 4

Hvad er 2. gen. cephalosporiner aktive mod?

Answer 4

MERE AKTIVE MOD G -
Gram-positive :Less than first-generation.
Gram-negative:Greater than first-generation: HEN (Haemophilus influenzae, EnterobacterandNeisseria+ PEcK

Question 5

Hvad er 3. gen. cephalosporiner aktive mod?

Answer 5

BREDERE SPEKTRUM INKL. PSEUDOMONAS
Gram-positive:Some (in particular those available in an oral formulation, and those with anti-pseudomonal activity) have decreased activity against Gram-positive organisms.
Gram-negative:increased activity against Gram-negative. Many of them are injectable drugs used for teating hospital-acquired infections. They are also able to penetrate the CNS, making them useful for treatment of meningitis

Question 6

Spektrum - penicilliner

• Penicillin G / V

Answer 6

(narrow spectrum, Gram +)

Question 7

Spektrum - penicilliner

Methicillin, oxacillin

Answer 7

(antistaph penicillins)

Question 8

Spektrum - penicilliner

Aminopenicillins

Answer 8

(more active against Gram-)

Question 9

Spektrum - penicilliner

Carbooxypenicillins

Answer 9

(active against PseudomonasandProteus)

Question 10

Spektrum - carbapenemer

• Imipenem, meropenem

Answer 10

(highly resistant to β-lactamases, injectable)

Question 11

Hvilke antibiotika er især konc. afhængige?

Answer 11

Aminoglycosides

Fluoroquinolones

Question 12

Måder at erhverve antibiotika resistens på

Answer 12

Mutation (vertical)
Gene transfer (horizontal)
  • Transformation
  • Transduction
  • Conjugation
Kan være kombi af mutation og gentransfer

Question 13

3 måder at transporterer resistensgener:

Answer 13

plasmid transfer
viral overførsel
transfer af fri dna

Question 14

Hvad er MRSA resistent overfor?

Answer 14

resistance to all β-lactams (penicillins &cephalosporins)
ofte multidrug resistant
- spredes vertikalt

Question 15

What is an ESBL?

Answer 15

Extended
Spectrum
Beta
Lactamase
Enzyme able to hydrolise/inactivate most β-lactams (except carbapenems) in Gram-negative bacteria
• Escherichia coliproducing ESBL are often resistant to alternative agents (multidrug resistance)
• Three major types: CTX-M, SHV and TEM
• Usually transmitted by plasmids (horizontal gene transfer)