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Flashcards in Antibiotics And Antivirals Deck (68):
1

Unknown cause sepsis

Flucoxacillin, metronidazole, gentimycin UHL
Meropenem KETS

2

Resp infections - generalised unknown source how would you manage

Give amoxicillin or co amoxicillin
This targets:
Gram positive bacteria e.g. Strep,staph
Gram negative bacteria: haemophillus, moxarella,

Allergic- give doxycycline or meropenem

3

Which microbes is amoxicillin effective against

This targets:
Gram positive bacteria e.g. Strep,staph
Gram negative bacteria: haemophillus, moxarella,
Also: helicobacter pylori, escheridia coli, proteus mirabilis, so use in GI inf.
Not effective : klebsilla, pseudomonas, serration, citrobacter, some gram negative aerobes

4

Mechanism of action of amoxicillin

Penicillin so beta lactam antibiotic
Disrupts cell wall synthesis in peptidoglycan cell walls so mostly effective against gram positive bacteria as rely more on their peptidoglycan cell wall.

5

Name other beta lactam antibiotics

Cephalosporins
Carbapenem- meropenem, eropenem.
Penicillins

6

Common causative organisms CAP. And their classification

Streptococcus pneumonia- gram positive cocci
Moxeralla catarhalis - gram neg, cocci
Haemophillus influenzae- gram negative bacilli

7

Curb 65

CURB
C- confused? Ab. Mental state score <8
Urea >7
RR >30
BP <90 or <60 diastolic
65 > age

0-1 low risk manage at home
2 hospital general wards
3+ consider ITU

8

Management of CAP

Antibiotics - amoxicillin or doxycycline. PO
If 2+score then: add doxycline po and then change to co-amox IV
If 2+ allergic: add meropenem IV and can change doxy to clarithromycin IV

9

HAP common organisms

Psumodmonas aerunginosa
Kelbsiella pneumoniae

10

HAP antibiotics

(Co- amoxiclav) not pseudo
Tazocin - pipereracillin with taxobactam

11

Co- amoxiclav uses against which microorganism

Same as amoxicillin but also for resistant microorgnansims, klebsiella
NOT PSEUDOMONAS
Gram positive aerobes- staph, strep, enterococcus
Gram negatives - haemophillus, e.coli. Moxarella, klebsiella, helicobacter pylori . Also: neisseria gonorrhoea,
Also: anaerobic - bacterioides, fusobacterium, peptostreptococcus.

12

Mechanism of co- amoxiclav

Amoxicillin- b lactamase inhibitor. Inhibit the binding oriteins that do cross linking in bacterial cell walls
Clavurinic acid- b lactamase inhibitor : class 2-5 -can really target gram negatives. But not pseudomonas
Irreversible inhibitor of thenlactamases

13

CI in using co amoxiclav

Penicillin allergy,
Cholestatic jaundice or liver dysfunction
hepatic toxicity is usually reversible but still have caution - don't use over 14 days

14

CI amoxicillin

Penicillinin celhalosporin allergy
C diff associated diarrhoea can occur

Can interact with methotrexate
Other antibiotics can interfere with amoxicillin (tetracyclines, macrolides)
Cna reduced effectiveness of OCP and oral antocoagulants

15

Antibiotics in aspiration pneumonia

Co amoxiclav Po or iv
Or meropenem

16

Antibiotics for acute COPD with acute lrti

Amoxicillin or co amox
Or doxyclijne

17

Doxycycline- class and mechanism of action

Broad spectrum tetracycline

Reversible inhibitor of 30s bacterial ribosome . Stops binding of tRNA to ribosome.

18

Name other classes of antimicrobials targeting ribosomes and which classes they treat

Tetracyclines- doxycycline - stop tRNA binding, work with gram positive, and negative and anaerobes
Aminoglycosides- gentimycin, streptomycin - gram neg. read mRNA abnormally .
Macrolides - erythromycin azithromycin. Gram positive and atypical pneumoniae . Stop mRNA translocation

19

Doxycline - uses, administration

- LRTI if penicillin allergic, milder skin infections if penicillin allergic,
Drugs of choice for intracellular organisms e.g. chlamydia trachomatus ,Lyme disease, mycoplasma, anthrax, rickettsia - all parasitic and penetrate well,

Administration: oral or iv

20

Tetracyclines
CI
SE

Bind to calcium e.g. Bones and teeth - so CI in young <8yrs, pregnant and lactating women. --> discoloured teeth

SE: N&V, C. difficile, thrush,idiopathic intercranial hypertension

21

New tetracycline - tigecycline - use and SE CI

Use: gram +ve -ve inc resistant strains. - skin soft tissue GI
CI - caution in liver
SE: inc LFTs, N&V, potosensitivity

22

Name some aminoglycosides, Their. Mechanisms of action. And overall sensitivity

Gentimycin, streptomycin, tobramycin, amikacin
Mechanisms: bactericidal antibiotics - strong ones, must give IV,
Bind to 30s ribosome and inhibit tRNA binding and ALSO promote misreading of mRNA
USe: gram negatives and gent/Tobramycin - can target pseudomonas.

23

Amino glycosides CI and SE

Ottotoxicity - damage 5th cranial nerve
Nephrotoxic - CI in renal failure. - Monitor aminoglycosides levels and serum creatinine
CI myasthenia gravis as impairs NM transmission

24

Resistance in aminoglycosides

Enzymes produced by the bacteria can inactivate the aminoglycosides

25

Use of aminoglycosides

Gentimycin
- unknown sepsis. - acute life threatening infection inc. pseudomonas. So use until sensitivities known.
- streptococcal endocarditis with penicillin and vancomycin
Amikacin - newest and has least resistance

26

Name some macrolides, their main use and mechanisms

Erythromycin, clarithromycin,
Gram positive - like penicillin - use in allergies
Mechansim: taken up by gram positive more than negatives - they bind to 50s sub unit and inhibit translocation

27

Erythromycin and clarithromycin uses, CI andSE

Oral or IV
Sim to penicillin - Gram positive cocci inc. MRSA, and B lactam resistant strains - so use in penicillin allergies!!
Also used in: mycoplasma pneumoniae and legionnaires

CI - not really
SE/interactions: liver metabolism and p450 inhibitors = accumulation of warfarin and inc. conc of statins (rhabdomyelosis) and calcineurin inhibitors etc.
SE: GI, Choletasis, inc. QT

28

Skin and bone infections/

Flucoxacillin

Or vancomycin if allergic

29

SE of penicillins

Rashallergy
NV
C diff
Cholestasis

30

First. Line antibiotic for c.difficile

Metronidazole oral

31

Name some anaerobes , and what you could use to treat

C.difficile
Bacterial vaginosis
Intra-abdominal, pelvic oral soft tissue. --- enclosed environments
E.coli, staphylococcus, clostridium - use metronidazole

Gram negatives:intra abdo infections , frusobacteroium (abscesses wounds), others causin aspiration pneumonia and soft tissue
Gram positives: clostridium, peptostreptococcus, other types causing pelvic neck and head. Infections.

32

Side effects and CI f metronidazole

Caution withliver problems
Inhibits warfarin metabolism - p450 inhibitor
Can cause disulfuram like reaction with alcohol

33

First line therapy UTI

Uncomplicated trimethoprim 3 days

34

Complicated uti

Trimethoprim (women)
Or Co-amoxiclav - recommended more in men
7 days

35

Pyelonephritis

Co-amoxiclav pO or IV if NBM

Allergic - ciprofloxacin or meropenem

36

Use of cephalosporins and name example

Alternatives to penicillins when allergies or resistance

Cefriaxone - meningococcus
Ceftazidime - neutropenic sepsis (broad spec)

37

Diabetic foot ulcers

Superficial flucoxacillin
Deep metronidazole - anaerobic

Allergic - doxycycline

38

Use of vancomycin and teicoplanin - mechanism

Complicated gram positives including MRSA

Inhibits peptidoglycan formation - from positive
Use septicaemia or endocarditis with MRSA. Or psydomenranous colitis (c.diff)

39

SE of teicoplanin and vancomycin

Nephrotoxic - monitor creatinine
Ototoxic
Platelet deficiency

Only IV - not oral

40

Use and mechansim of carbapenems

B lactam inhibitors but very rewesistant to most b lactamases. Wide spec. Acts against gram negatives and gram positives inc. pseudomonas and MRSA
IV
Meropenem
Ertapenem (not for pseudomonas)

41

Menigitis

Gram -ve cocci
Give cefriaxone

42

Use of rifamycin

Mycobacterium
Legionella
Meningococcal prophylaxis

43

Se and CI with rifamycin

Epatitis
Gi
Cna effects
Myelosu[rssion
Red secretions- urine sweat s alive tears

44

Mechansim or tripmthroprim and co-trimoxazole

Folate synthesis inhibitors

45

Tb treatment

Rifamycin 4 mths
Isoniazid 4 mths
Pyrazinamide 2 mths
Ethambutol 2 mths

46

SE of ethambutol

CI optic neuritis - ocular toxicity and colour blindness
Don't use in young. Kids

47

Cholecytisis infection, peritonitis, or hepatobilary

Treat like sepsis IV - amoxicillin metronidazole gentimycin (or meropenem if allergic)

48

Abdominal gastroenteritis or other complaint - not as severe

Ciprofloxacin or cefriaxone

49

Use of gentimycin

Aminoglycosides
Gram negatives inc. pseudomonas

50

SE of pyramizadole

CI in gout,
Caution in DM
Hepatotoxic, photosensitivity

51

Se or isoniazid

Caution in liver disease
Peripheral neuropathy - caution in DM - common
Rare - psychotic episode

52

Name some cutenous fungal infections

Dermatophytosis
Candidiasis
Malassezia

53

What is dermatopytosis

Ringworm
Scale and pruitis - itchy
Can be circular
Also skin and blisters between toes

54

Malassezia

Greasy skin - hypo or hyperpigmented ras - sebrharrhoeic dermatitis (scaling and danddruff)]
RF acne

55

RF Diagnosis and treatment of superficial fungal infections

Immmunocop. Moist environments. Antibiotics
Diagnsis - clinical.skin scrapings
Treatment: topical -azole e.g. Imisazoles or triadazoles
. Or terbinafine 1-4wks
Topical nystatin (candidiasis )

56

Name a common anti-fungal for superficial infections

Triazoles
- fluconazole

57

Candiasis infections - superficial

Nystatin or amphotericin
(Polyenes - antifungals)

58

Invasive fungal infections - name som organisms

Candidiasis-- immunocomp
Cryptococcosis --> menigitis or pneumonia
Histoplasmosis --> from soil with bat or birt faeces
Blastomycosis

59

RF for invasive fungal.

RF- infection malignancycritical illness e.g. ITU, transplant surgical - GI perforation, burns immunosuppressed

60

Investigating serious infections - especially suspected fungal and those with RF

3 blood culture samples 3 different sites, same time/
Microscopy and immunohistocemistry
- consider antigen antibody testing

61

Managing invasive candidiasis

Repeated tissue cultures
Remove potential source- catheter and sample
Give cocktail of antifungals: triazole e.g. Fluconazole. Ecinocandins (terbinafine) and others

62

7 types of antiviral s

Think 7 steps
1) inhibit penetration - palivzumab (RSV propylaxis in infants at risk)
2) Inhibit uncoatting' - rare
3) Integrase inhibitors - prevent integrating into nucleus
3) Replication - inhibit viral DNA polymerase- aciclovir, galciclovir. - herpes.
- antiretrovirals - NRTIs
4) inhibit exit - neuramindase inhbitors - oseltamavir, zanamivir
5) prevent maturation/bodies response
- protease inhibitors - prevent maturation of virus
-- immunomodulators - interferon alpha

63

Treatment complicated influenza

Oseltamivir

64

Treating HIV - pharm

2x NRTI backbone - combo of 2 NRTIs e.g. Tenofovir emtricitabine
Plus. 1 of:
- Protease inhibitor- atazanavir
- NNRTI
- Integrase inhibitor


Also monitor adherence, LFTs glucose, viral load,

65

Managing HIV

Pharm
Counselling -
Screen forinfectins and malignancy - co-trimoxaloe prophylaxis
Base lines - CD4 viralload LFTelectrolytes pregnancy resistance
Review medications

66

Antivirals in hepatitis - hep C


Interferons -modulate hosts response - old and now phased out for Hep C with serotype specific treatments

67

Hepatitis B treatment

Generally upportive - avoid alcoholimmunise contacts Antivirals with interferon if. High risk of liver disease

68

Hepatitis A treatment

Supportive avoid alcohol