Antimicrobial Therapy Flashcards Preview

Stage 2: Inflammation > Antimicrobial Therapy > Flashcards

Flashcards in Antimicrobial Therapy Deck (48)
Loading flashcards...
1
Q

What is the most common cause of GI infection in the UK?

A

Campylobacter

2
Q

What is the standard treatment of sepsis

A

Co-amoxiclav + gentamicin (broad spectrum)

3
Q

What are platelet levels in sepsis?

A

Low

4
Q

What scan would you use to see an (GI) abscess?

A

CT

5
Q

How would you treat a large GI abscess e.g. from appendicitis?

A

1) Washout and drainage of pus and dead tissue in theatre
2) Send pus to lab to culture bacteria e.g. E.coli
3) Treat with antibiotics e.g. co-amoxiclav

6
Q

What bacteria is a common cause of intra-abdominal sepsis?

A

E.coli

7
Q

What infection has a 100% mortality if untreated?

A

Endocarditis

8
Q

How do you treat with antibiotics?

A

Start with broad spectrum/empirical antibiotics and then narrow down the therapy after getting microbiology results

9
Q

What should you write on a drug chart when giving an antibiotic?

A

Indication and stop date

10
Q

How do you give antibiotics as part of surgical prophylaxis?

A

Only a few doses before, maybe during if long surgery and 48h after

11
Q

What is a common antibiotic-associated infection?

A

C.difficile

12
Q

What are the 3 possible results of antimicrobial susceptibility disc testing?

A

1) R = resistant
2) I = intermediate but mainly resistant
3) S = sensitive

13
Q

What is MIC?

A

Minimum inhibitory concentration = the lowest concentration of the antibiotic being tested that inhibits growth of the organism in a broth

14
Q

What is MBC?

A

Minimum bactericidal concentration = the lowest concentration of the antibiotic that kills the organism

15
Q

What are the 7 main classes of antibiotics?

A

1) Beta lactams (penicillins, cephalosporins and carbapenems)
2) Macrolides
3) Tetracyclines
4) Trimethoprim and co-trimoxazole
5) Quinolones
6) Aminoglycosides
7) Glycopeptides

16
Q

Why are cephalosporins used less now?

A

They are implicated in C difficile

17
Q

What is the first line antibiotic in chest infection (gram negative)?

A

Amoxicillin

18
Q

Which antibiotics are frequently given for UTIs?

A
  • Cefalexin (cephalosporin)

- Trimethoprim

19
Q

What type of bacteria is flucloxacillin commonly used again?

A

Staphylococcus

20
Q

What are the 3 macrolides?

A

1) Clarithromycin
2) Erythromycin
3) Azithromycin

21
Q

What are macrolides esp. clarithromycin used for?

A

Used in penicillin-allergic patients against gram positive bacteria (staphylococci or streptococci) in e.g. SSTIs, throat infections, atypical pneumonia

22
Q

When are the tetracyclines used e.g. doxycycline?

A
  • Penicillin allergic patients who suffer side effects with macrolides
  • Broad spectrum
  • Respiratory tract and SSTIs
  • Atypical CAP
  • Resistance is common
23
Q

What is co-trimoxazole used for?

A
  • Infections in immunocompromised patients e.g. prophylaxis and treatment of PJP
24
Q

What are quinolones (ciprofloxacin) used for?

A
  • Against gram-negative bacteria

- Newer ones more useful against gram-negative e.g. S.pneumoniae

25
Q

What is the most common aminoglycoside?

A

Gentamicin

26
Q

What are aminoglycosides used for?

A
  • Gram-negative bacteria
  • Useful synergy with penicillins against streptococci
  • Serious sepsis (quick acting)
  • V potent when organism is sensitive
  • Often given with beta-lactam to extend spectrum of cover
27
Q

What is the problem with aminoglycosides?

A
  • They can cause vestibulocochlear nerve and renal toxicity (nephrotoxic and neurotoxic) which can lead to hearing loss
  • Serum levels must be measured
28
Q

What are glycopeptides used for?

A
  • ONLY gram-positive bacteria (staphylococcus, streptococcus, enterococcus)
  • MRSA
  • Sometimes used when patients are penicillin allergic
29
Q

What are the two glycopeptides?

A

1) Vancomycin

2) Teicoplanin (less toxic)

30
Q

What is vancomycin used for and what has to be done with it?

A
  • Broad spectrum against gram-positive
  • Used to treat C. diff
  • Potentially nephrotoxic, need to measure blood levels
31
Q

What is metronidazole used for?

A
  • Active against anaerobes
  • e.g. intra-abdominal sepsis where may have been leakage of gut contents
  • Amoebae
  • Trichomonas vaginalis
32
Q

What is linezolid used for?

A
  • Gram positive bacteria
  • MRSA
  • Glycopeptide-resistant enterococci (VRE)
33
Q

What is chloramphenicol used for?

A
  • Bone marrow toxicity so only used occasionally for meningitis and topical treatment of eye infections
  • e.g. for v penicillin allergic pt with unknown cause bacterial meningitis
34
Q

What is penicillin used for?

A
  • Serious streptococcus

- Meningococcal meningitis

35
Q

What is ceftriaxone used for?

A

Blind therapy for bacterial meningitis

36
Q

What two beta-lactams are effective against pseudomonas?

A
  • Piperacillin-tazobactam

- Ceftazidime

37
Q

What is fosfomycin used for?

A

Multi-resistant gram-negative infections

38
Q

What is fidaxomicin used for?

A

Elected cases of severe or recurrent C.difficile diarrhoea cases

39
Q

What is colistin used for?

A

Multiple or pan resistant gram-negative infections

40
Q

What is daptomycin used for?

A

Gram-positive bacteria (to replace glycopeptide - similar activity)

41
Q

What is fusidic acid used for?

A
  • Staphylococcal infections only

- Topical

42
Q

What is bad about erythromycin?

A

GI side effects

43
Q

What is rifampicin used for?

A
  • Gram-positive bacteria
  • Prosthetic valve endocarditis and other prosthesis infections - typically combined with anti-staph agent e.g. vancomycin
  • Part of first line TB regimen
44
Q

What are coliforms (problem resistance bacteria)?

A

Klebsiella, enterobacter

45
Q

Where are yeasts (candida e.g. albicans) typically found in serious infections?

A

Urinary tract, intra-abdominal, bloodstream

46
Q

Where are moulds (aspergillus) typically found?

A

Sinusitis, pulmonary, disseminated, transplant, haemato-oncology

47
Q

What is the main antifungal given orally for systemic infection?

A

Fluconazole (but resistant problems)

48
Q

What is the main antifungal given for serious fungal infection with the most predictable broad spectrum cover>

A

(Liposomal) amphotericin B