Antibiotics and Hospital Acquired Resistance Flashcards
What are antibiotics?
Antimicrobial agents produced by microorganism that kills or inhibits others
What are antimicrobials?
Chemicals that selectively kill/inhibit microbes
What is a bacteriostatic?
An agent thats prevents bacteria from growing and reproducing
What do beta-lactams do?
Interfere with peptidoglycan synthesis, resulting in faulty cell wall
Name 2 beta-lactams:
Methicillin
Penicillin
What is Prontonsil?
A synthetic bacteriostatic antibiotic. (Sulphonamide)
Used for Strep infrections and UTIs
What are the consequences of Anti-microbial resistance?
Increased stay, morbidity, cost and mortality
Use of more toxic second choice less effective drugs
What are the major Gram +ve resistant pathogens?
S. aureus (MRSA, VISA)
C. diff
M. tuberculosis (Multi-drug resistant TB (MDRTB))
VRE (Vancomycin resistant enterococcus)
What are the major Gram -ve resistant pathogens?
Super gonorrhoea
E. coli (ESBL)
Name an aminoglycoside drug that blocks 30S ribosomal subunit:
Streptomycin
What can vancomycin be used to treat?
MRSA, but toxic and not v. effective
What are the four methods of resistance?
Altered target site
Inactivation of antibiotic
Altered metabolism
Decreased drug accumulation
What are altered target sites?:
Acquired or spontaneous mutations of AB target, so still functional but AB cannot bind OR an new target is produced
What is inactivation of antibiotic?
Enzymatic degradation/alteration of AB.
E.g. beta-lactamases break down ABs like methicillin
What is altered metabolism?
Increased production of substrates to outcompete competitive inhibitor ABs
