Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PR3151 > FINALSSSSS > Flashcards

FINALSSSSS Flashcards

IC6, IC13-19

1
Q

Class side effect of carbapenem

A

Some neurotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

only BETA LACTAM active against MRSA

A

ceftaroline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Does vancomycin require dosage adjustment in renal impairment or hepatic impairment? WHYYYYYYY?

A

renal impairment.
75% of drug excreted unchanged in urine. renal impairment will affect PK of drugs and require dosage adjustment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Is vancomycin renally cleared or hepatically cleared?

A

Renally cleared
(and hence requires renal adjustments)
(it is also nephrotoxic)
(i also dont want to study anymore)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

co-trimoxazole is time/concentration/AUC dependent killing?

A

concentration dependent killing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

spectrum of activity for co-trimoxazole

A

susceptible to enterobacterales (E. coli, klebsiella, proteus)

yellow for MRSA, MSSA, strep pneumo, H. influenzae, ESBL-producing and AmpC-type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

main indication for co-trimoxazole

A

mostly used in UTI
(more for UTI in men but local resistance to co-trimoxazole is quite high so yellow susceptibility)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

main elimination pathway for sulfamethoxazole and trimethoprim

A

sulfamethoxazole - renal elimination + hepatic metabolism

trimethoprim - renal elimination mainly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

contraindications to co-trimoxazole (& reasons)

A
  • severe hepatic/renal impairment (due to elimination)
  • pregnancy (both, due to possible folate deficiency, and can cross placenta)
  • infants (sulfo, risk of kernicterus due to displacement of bilirubin from serum albumin)
  • history of co-trimoxazole induced thrombocytopenia (dont want to risk this again)
  • existing folate deficiency induced megaloblastic anemia (already deficient and anemic, dont want to worsen)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

monitoring parameters for co-trimoxazole & reasoning

A
  • CBC with differential (hematological disorders)
  • LFT & RP (renal and hepatic function)
  • Serum K (K-sparing diuretic - trimethoprim)
  • Urine (in case of crystalluria due to sulfamethoxazole)
  • Allergy reactions (in case of hypersensitivity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Difference between MOA for linezolid VS macrolide/clindamycin

A

linezolid is a protein synthesis inhibitor that binds to 50s ribosomal subunit near INTIATOR COMPLEX SITE

macrolide/clindamycin: it binds to 50s ribosomal subunit near PEPTIDYL TRANSFER SITE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

spectrum of activity for linezolid

A

gram positive & some anaerobes

subjected to efflux in gram negative (no gram neg coverage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

common use of linezolid

A

against MRSA in SSTIs (either vancomycin/linezolid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Can I use linezolid with paroxetine/venlafaxine?

A

No, risk of serotonin syndrome. Should not use linezolid with MAOi/SSRIs/SNRIs/Serotonin agonists. Avoid tyramine-rich food.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

elimination pathway for linezolid

A

hepatic metabolism > renal excretion
–> caution in severe impairment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

monitoring parameters for linezolid

A
  • CBC with differential (hematological disorders)
  • fingertip numbness/tingling/weaknes & eyesight changes (due to potential irreversible peripheral neuropathy/optic neuritis with >28days of use)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how to prevent crystalluria for co-trimoxazole

A

take with water and hydrate regularly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

spectrum of activity for clindamycin

A

gram pos and anaerobes (intrinsic resistance by gram neg and c diff)

local resistance to clindamycin quiet high.. so all gram pos yellow except
enterococcus faecalis & C diff.

ONLY GREEN FOR gram pos anaerobe (finegoldia magna)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

elimination pathway of clindamycin

A

hepatic metabolism&raquo_space;> renal excretion
–> caution in severe liver impairment (and maybe severe renal impairment)
–> monitor liver function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

contraindications of clindamycin

A

pseudomembranous colitis (like in C diff infection), ulcerative colitis or any colonic inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

monitoring parameters for clindamycin

A
  • Liver function (major elimination pathway)
  • changes in bowel frequency / colitis (monitor for colonic inflammation)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Why does metronidazole only target anaerobes (so well)
my favourite antibiotics <3
少给我麻烦 <3

A

metronidazole has cytotoxic free radicals that cause protein and DNA damage which requires strong reducing conditions (aka anaerobic cnditions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

common side effect of metronidazole for PO

A

unpleasant, metallic taste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

elimination pathway of metronidazole

A

(BOTH)
hepatic metabolism + renal excretion.
caution in renal/hepatic impairment, may need dose adjustment in severe hepatic impairment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

monitoring parameters for metronidazole

A
  • liver function (major elimination pathway)
  • neurological symptoms (eyesight changes, fingertip numbness/weakness, seizures, mental state) (due to CNS/PNS ADR such as convulsive seizures, optic and peripheral neuropathy, confusion. vertigo, hallucinations)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

DDI and DFI with metronidazole

A
  • warfarin (increase PTT & INR)
  • disulfiram
  • alcohol (disulfiram-like reaction with alcohol intake)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Antibiotics used to treat CNS infection (6)

A

penicillin
ceftriaxone
cefepime
ceftazidime
meropenem
vancomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

first line therapy for TB (4+1)

A
  • rifampicin
  • isoniazid
  • pyrazinamide
  • ethambutol
  • streptomycin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

for latent TB, what is the regimen?

A

single agent therapy
- 4mth rifampicin OR
- 6mth isoniazid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

standard regime for active TB

A

(2RIPE/4RI)
intensive phase: 2 months x RIPE OD
continuous phase: 4 months x RI OD/3X/WEEK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

role of streptomycin as part of first line TB therapy

A

May sometimes replace ethambutol in intensive phase due to lower frequency of acquired resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how to determine cure of TB?

A

> =2x negative smears/culture (negative in the last month + >=1 other occasion)

failure = postive @ or after 5 months

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

monitoring parameters before starting TB therapy and during TB therapy.

A

before starting:
- baseline AST&ALT (ensure baseline liver function)
- weight
- vision acuity and colour vision check due to ocular toxicity risk by EMB

during therapy:
- monitor LFT if high risk for hepatic toxicity
- weight
- monitor for drug-induced hepatotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

hepatotoxicity in drugs from high to low

A

PZA > INH > RMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

renal dosage adjustment in which TB drugs?

A

PZA & EMB - mainly renal excretion especially for <30ml/min

Streptomycin - reduce dose in impairment + nephrotoxic risk (aminoglycosides class effect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

4 steps for the antimicrobial approach

A
  1. confirm presence of infection
  2. identify likely pathogen
  3. select antimicrobial regimen
  4. monitor response & plan
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What do you look for to confirm presence of infection?

A
  • risk factors of patient
  • subjective evidence
  • objective evidence
  • possible site of infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Common sites of infection

A

Blood, Respi, GIT (intra-abdominal), SSTI, UTI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

abnormal vital signs -
temperature:
BP:
HR:
RR:
mental:

A

temperature >=38.0degC
SBP < 100mmHg (may also need to observe baseline, patient’s normal BP trend)
HR > 90bpm
RR > 22bpm
mental: drop in Glasglow coma scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

abnormal labs:
Whites
Neutrophils
C-reactive protein
Erythrocyte sedimentation rate

A
  • elevated (14-15) or depressed (2-3) x 10^9/L (normal is 4-10x10^9/L) white count
  • ~90% neutrophils (observe trend; normal is 45-75%)
  • infection CRP > 40mg/L
  • increased ESR for bone and joint inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

how does procalcitonin aid in clinical diagnosis?

A

Guides starting/continuation of Abx in patients.

<=0.25mcg/L usually strongly discourages antibiotics

0.25-0.5 is discouraged also

above is more encouraged, if it increased or >1mcg/L, strongly encourage abx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Which groups of patients can have elevated procalcitonin without infection (and should take note)?

A
  • traumatic brain injury (TBI)
  • ESRF (procalcitonin cleared by kidneys, accumulation due to ESRF is possible)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

In patients with G6PD deficiency, what antibiotics should they avoid?

A

Sulfonamide, nitrofurantoin, older generation fluoroquinolone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Antibiotic with no shared side chain as penicillins (can consider in penicillin allergy)?

A

Cefazolin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Abx classes generally SAFE in pregnancy & lactation

A

beta-lactams and macrolides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Abx classes generally CAUTIONED in pregnancy & lactation

A

co-trimoxazole, fluoroquinolones, tetracyclines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Nephrotoxic Abx

A

aminoglycosides, high dose vancomycin, amphotericin B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Hepatotoxic Abx

A

pyrazinamide, amoxicillin-clavulanate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Bactericidal drugs (better to use for immunocompromised patients)

A

beta-lactam, (fluoro)quinolones, aminoglycosides, vancomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Why is daptomycin not used in respiratory infections?

A

Daptomycin gets destroyed by lung surfactant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Why are ciprofloxacin and co-trimoxazole drugs of choice for prostatitis?

A

They distribute well to the prostate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Common bacteriostatic antibiotics (inhibit protein synthesis)

A
  • macrolides
  • tetracyclines
  • trimethoprim & sulfonamides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Common CYP3A4 inhibitors

A

NDHPCCB - veramapil, diltiazem

azole antifungals - itraconazole, ketoconazole

macrolide antibiotics - clarithromycin, erythromycin

antiHIV - ritonavir, saquinavir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

common CYP3A4 inducers

A

rifampin/rifampicin

HIV NNRTIs - efavirenz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Which antibiotics can cause QTc prolongation?

A

Macrolides - clarithromycin, erythromycin

Fluoroquinolons - levofloxacin, ciprofloxacin

azoles - itraconazole, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Which abx can cause photosensitivity?

A

tetracycline (doxycycline), sulfonamides, quinolones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Which conditions predisposes infections?

A

DM, cirrhosis, neutropenia, HIV, transplant&immunosuppressive medications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

In SSTIs which bacteria infection commonly presents with pus?

A

Staphylococcus aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

common pathogens for impetigo

A

staphylococci/streptococci

bullous form - toxic strains of S. aureus

mainly looking at MSSA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

common pathogens for ecthyma

A

most frequently caused by group A streptococci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Regimen for mild, limited lesions in impetigo

A

topical mupirocin BD x 5days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What’s the concern for topical mupirocin?

A

Increasing resistance to mupirocin since it’s used to decolonise MRSA in hospitals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Empiric treatment for impetigo/ecthyma & duration

& if penicillin allergy

A

PO cephalexin or cloxacillin for 5-7days

penicillin allergy: PO clindamycin or non cross reacting B-lactams (cefazoline, cefuroxime)

(dont have to consider MRSA since CA-MRSA is not common in SG)

64
Q

In purulent lesions (furuncle, abscess, carbuncles, purulent cellulitis), what are the common pathogens?

A
  • mainly by S. aureus (purulence)
  • some beta-hemolytic streptococci (:o blood agar plate?!?!?)
  • multiple organisms incl gram neg & anaerobes in abscess involving perioral/perirectal/vulvovaginal areas
65
Q

Mild purulent SSTI treatment

A

Incision & drainage
Warm compress to promote drainage

66
Q

Moderate (with systemic symptoms) purulent SSTI treatment

A

Incision & Drainage + ORAL antibiotics

PO cephalexin or cloxacillin
penicillin allergy: clindamycin

for 5-10days

67
Q

Severe purulent SSTI treatment

A

Incision & Drainage + IV antibiotics

IV cefazolin or cloxacillin
penicillin allergy: clindamycin OR vancomycin

for 5-10days

68
Q

Mrs T has a purulent skin abscess in the vulvovaginal area. She presents with temperature of 38.4degC and malaise. She does NOT have a penicillin allergy.

What should her treatment be?

A

PO Amoxicillin-clavulanate for 5-10days

(potentially gram neg / anaerobes infection due to abscess being in vulvovaginal area)

69
Q

In nonpurulent infections (cellulitis, erysipelas), what are the common pathogens?

A
  • mainly beta-hemolytic streptococcus
  • usually group A strep ^
  • SA less common
  • with water exposure: aeromonas, pseudomonas, vibrio
70
Q

In nonpurulent infections (cellulitis, erysipelas), what antibiotic can cover for aeromonas, pseudomonas and vibrio if lesion has been exposed to water?

A

Ciprofloxacin

71
Q

Mild nonpurulent infection treatment & duration

A

mainly only cover strep pyogenes, ORAL abx

PO Penicillin V, cloxacillin, cephalexin for 5-10days

penicillin allergy: clindamycin

72
Q

Moderate (w systemic signs/mildly purulent) cellulitis/erysipelas treatment & duration

A

strep pyogenes + MSSA cover, may IV

PO/IV cloxacillin, cephalexin/cefazolin for 5-10days

penicillin allergy: clindamycin

73
Q

Severe (systemic signs, failed PO therapy OR immunocompromised) cellulitis/erysipelas treatment & duration

A

BROADER COVERAGE (all v broad spectrum abx)

IV piperacillin-tazobactam, cefepime, meropenem for 5-10days

74
Q

What abx to add on when there is MRSA risk factors?

aka MRSA colonisation, previous Abx use, previous hospitalisation, etc

A

IV vancomycin, daptomycin or linezolid

Daptomycin cannot cover MRSA in respiratory infections

75
Q

How to determine infection of diabetic foot ulcers/pressure ulcers?

A

Purulent discharge OR
>= 2 signs of inflammation: red, swelling, warm, tender, pain, induration (hardness/scabbing)

76
Q

Common causative organisms for DFI

A
  • Staphyloccocus aureus & streptococcus spp most common
  • gram negative enterobacterales if in chronic wounds/prev treated with Abx
  • PsA less common, but possible (esp w water exposure)
  • anaerobes in hypoxic wounds (ischemic/necrotic wounds)
77
Q

Mild DFI
Definition -
What to cover -
Antibiotics to use -

A

Definition:
Infection of skin and/or SC tissue + erythema <=2cm around ulcer + no systemic signs

What to cover:
Staph aureus + Strep pyogenes

Antibiotics to use:
PO cephalexin, cloxacillin, clindamycin (penicillin allergy)

MRSA risk factors - PO doxycycline, co-trimoxazole, clindamycin

78
Q

Moderate DFI
Definition -
What to cover -
Antibiotics to use -

A

Definition:
Infection of deep tissue (bone/joint) OR erythema >2cm around ulcer
+ no systemic signs

What to cover:
Staph aureus + strep pyogenes + gram neg (+/- PsA) + anaerobes

Antibiotics to use: (Initial IV)
- amoxicillin-clavulanate (all except PsA)
- cefazolin/ceftriaxone (gram negs, gram pos, no anaerobes) + metronidazole (anaerobes)

MRSA risk factors - IV vancomycin/daptomycin/linezolid

79
Q

Severe DFI
Definition -
What to cover -
Antibiotics to use -

A

Definition:
Infection of deep tissue (bone/joint) OR erythema >2cm around ulcer
+ YES systemic signs

What to cover:
Staph aureus + strep pyogenes + gram neg (incl PsA) + anaerobes

Antibiotics to use: (initial IV)
- piperacillin-tazobactam
- meropenem
- cefepime (gram neg, gram pos, no anaerobes, YES PSA) + metronidazole (anaerobes)
- ciprofloxacin (gram negs, YES PSA) + clindamycin (gram pos, if penicillin allergy)

MRSA risk factors - IV vancomycin/daptomycin/linezolid

80
Q

Duration of therapy for DFI with NO BONE INVOLVEMENT

A

Mild - 1-2weeks
Moderate - 1-3 weeks
Severe - 2-4 weeks

generally takes longer than other infection, bacteria may be harder to clear

81
Q

Which 2 groups of patients to screen for asymptomatic bacteriuria (ASB)?

A
  1. pregnant women - prevent pyelonephritis, low infant birth weight and preterm labour
  2. patients going for invasive urologic procedure in which trauma/bleeding is expected - prevent bacteremia and urosepsis
82
Q

4 natural defense mechanisms of the urinary tract

A
  • Micturition (peeing) with increased diuresis stimulated by bacteria→ empty bladder
  • Antibacterial properties of urine & prostatic secretion
  • Anti-adherence mechanism to prevent bacterial attachment to the bladder
  • Inflammatory response with neutrophils (neutrophils camp in the cells there and ready to attack) → phagocytosis
83
Q

How to prevent more UTIs? Non-pharmacological suggestions

A
  • drink lots of fluid to flush bacteria (pee more, flush more)
  • urinate frequently and whenever you feel the urge (不要忍，不要憋，不要尿道管发炎！）
  • urinate shortly after sex (flush away bacteria that may have entered urethra during sex)
  • wipe from front to back, especially after bowel movement (大便）(for women)
  • wear cotton underwear and loose fitting clothes to keep area dry. tight clothes trap moisture and help bacteria grow
  • using diaphragm or spermicide can lead to UTI > may want to modify birth control method
84
Q

Mrs T (again) is on birth control by using a diaphragm since she does not want to have kids now (拼事业，什么是组织家庭？？？？）but anws, her sexual activity with her husband (only sexual partner) is regular. Her past medical history includes Type 2 Diabetes Mellitus and allergic rhinitis.

She recently renovated her house and is currently on chlorpheniramine to help with her allergic rhinitis symptoms.

What are her risk factors for UTI?

A
  • female
  • diaphragm birth control
  • sexual intercourse
  • diabetes
  • anticholinergic drug

10/10 ready to get a UTI!!!

85
Q

Subjective symptoms in lower UTI (cystitis)

A

Dysuria
urgent
frequent
nocturia
suprapubic heaviness or pain
gross hematuria (blood in pee)

86
Q

Subjective symptoms in upper UTI (pyelonephritis)

A

Fever, rigors, headache, N/V, tiredness, flank pain (press and lower back hurts), costovertebral tenderness (renal punch - done by doctor), abdominal pain

87
Q

Common pathogens for ASCENDING UTI (from UT to pyelo or bacteremia)

A

Gram negative enterobacterales: E coli, klebsiella, proteus

88
Q

Common pathogens for DESCENDING UTI (from blood to UT)

A

staphylococcus aureus, mycobacterium TB

89
Q

2 chemical tests for UTI

A
  1. nitrites - positive test indicates gram negative bacteria
  2. leukocyte esterase test - positive test = WBC in urine (pyuria)
90
Q

Urine cultures are not needed in uncomplicated cystitis, but which groups patients may require pre-treatment culture?

A
  • pregnant women
  • recurrent UTI within 2 weeks/frequent
  • pyelonephritis
  • catheter-associated
  • Men with UTI
91
Q

Likely pathogen in community-acquired/uncomplicated UTI

A
  • E coli (~85%) - gram neg
  • staphylococcus saprophyticus (5-15%) - gram pos
  • enterococcus faecalis (+), klebsiella, proteus
92
Q

Likely pathogen in healthcare-associated UTI

A
  • Ecoli (~50%)
  • enterococci (+)
  • proteus, klebsiella, enterobacter, PsA
93
Q

First line empiric therapy for uncomplicated cystitis

A

Nitrofurantoin for 3-5 days

94
Q

Second line empiric therapy for uncomplicated cystitis

A
  1. Fosfomycin 3g single dose
    - contraindicated in CrCl < 10ml/min
    - SE includes heartburn
  2. amoxicillin-clavulanate (augmentin 1g for severe cases, 625mg for mild-moderate)
    - contraindicated in history of amox-clav associated hepatic dysfunction or jaundice
    - SE includes mucocutaneous candidiasis
95
Q

Why is nitrofurantoin and fosfomycin not used in men with UTI?

A

Nitrofurantoin and fosfomycin do not distribute well to the prostate (unlikely to reach therapeutic levels)

96
Q

Why is co-trimoxazole an alternative in cystitis?

A

Local resistance to co-trimox is quite high. Culture before giving abx and monitor after giving co-trimox.

3days for treatment, 7days in men

97
Q

First line empiric therapy for uncomplicated pyelonephritis

A

Amoxicillin-clavulanate 825/125mg (Augmentin 1g) BD x 10-14days (higher dose and longer than cystitis)
- contraindicated in history of amox-clav associated hepatic dysfunction or jaundice
- SE includes mucocutaneous candidiasis

98
Q

Second line empiric therapy for uncomplicated pyelonephritis

A

Cefuroxime axetil (2nd gen cephalosporin) x 7-10 days
- SE includes abdominal pain
- cross reactivity with penicillin is unlikely, but still use with caution
- effectiveness reduced by increase in gastric pH (DDI: PPIs, antacids, H2RA) –> administer Abx 1h before or 2h after

99
Q

Good abx to use for UTI when ASTs are available (3)

A
  • ciprofloxacin x 7 days
  • levofloxacin x 5 days
  • co-trimoxazole x 7/14 days
100
Q

Why is amoxicillin not used for UTI?

A

Local resistance of E coli to amoxicillin is 40-50% (too high already)

101
Q

In complicated pyelonephritis/UTI, what empiric therapy to use?
(need IV liao ah,,,)

duration of therapy:
NO MDRO risk factors:
MDRO risk factors:

A

duration of therapy: 7-14days (14d for men!!, that’s kinda L if u ask me)

NO MDRO risk factors - cover E coli and proteus
- amoxicillin-clavulanate 1.2g OR ceftriaxone
+/- gentamicin 5mg/kg to cover for ESBL producing/AmpC type (distributes well to urine and kidney)

MDRO risk factors - cover ESBL-producing E coli&klebsiella, proteus, PsA
- Cefepime (incl PsA, may not be effective against ESBL-producing Klebsiella) +/- amikacin 15mg/kg/day (cover ESBL producing Klebsiella)
- piperacillin-tazobactam (okok coverage for ESBL in urine) OR meropenem OR imipenem

102
Q

Why are nitrofurantoin and fosfomycin not used in complicated pyelonephritis?

A

Does not distribute well to renal parenchyma

103
Q

Mrs T is now pregnant (guess her birth control is useless lolsies). And SHE GOT UTI!!!

What antibiotics should be avoided for her and which can be used?

A

YES:
- beta-lactams (generally safe in pregnancy) aka amoxicillin-clavulanate (best choice)
- fosfomycin: if cystitis then ok

NO:
- ciprofloxacin (fetal risk cannot be ruled out)
- co-trimoxazole in 1st and 3rd trimester (1st trimester - folate antagonism can cause neural tube defects; 3rd tri - risk of kernicterus due to sulfamethoxazole)
- nitrofurantoin @ term (38-42 weeks) (concern that fetus will be G6PD deficient)

104
Q

Duration of therapy for catheter-associated UTI

A

7 days with prompt resolution (no fever in 72h) or 10-14 days for delayed response

105
Q

Does influenza have high or low grade fever?

A

High

106
Q

Common pathogens for common cold

A

rhinovirus, coronavirus

107
Q

Common pathogens for Influenza

A

Influenza A and B

108
Q

How fast should I initiate influenza antiviral?

Who should be started on antiviral?

aka oseltamivir

A

best within 48h, up to 5 days

For people who are hospitalised/high risk of complications/severe, complicated or progressive illness

109
Q

How to tell if pharyngitis is bacterial?

A

Sore throat with tonsillar exudates, fever, swollen lymph nodes WITHOUT viral symptoms (runny nose, etc)

110
Q

Common pathogen for bacterial pharyngitis

A

Group A beta-hemolytic streptococcus (S. pyogenes)

111
Q

Modified centor criteria is a list of criteria to determine if a patient has strep pharyngitis.
What are the components of this criteria?

What is the diagnosis for each number of points (max 6)?

A
  • fever >38.0degC
  • swollen lymph nodes
  • tonsillar exudates
  • absence of cough
  • age (+1 if 3-14, -1 if above 45)

0-1 points - presumed viral, no Abx required
2-3 points - test for strep pharyngitis, Abx if positive
4-5 points - high risk of Strep pharyngitis, initiate empiric Abx

112
Q

Empiric first line therapy for bacterial pharyngitis

+ penicillin allergy & their concerns

+ duration of therapy

A

First line:
PO Amoxicillin 500mg Q12H
PO Penicillin 250mg Q6H
(amox-clav too broad, no need)

Penicillin allergy:
if not severe - PO cefuroxime
else:
- PO azithromycin
- PO clarithromycin
- PO Clindamycin
(concerns of QTc prolongation)

Duration of therapy: 10 days (5 days for azithromycin)

113
Q

How do bacteria invade body system when a patient has viral rhinosinusitis?

A

Inflammation obstruct sinuses and trap nasal secretions inside the nose –> bacteria also get trapped and have the chance to proliferate

114
Q

Symptoms suggestive of orbital cellulitis/CNS involvement which warrants referral to ED in acute rhinosinusitis

A
  • limited ocular movements
  • acute vision changes
  • confusion
  • unilateral weakness
115
Q

Most common pathogens for acute bacterial rhinosinusitis

A

Streptococcus pneumoniae
Haemophilus influenzae

116
Q

How to differentiate between anaerobic bacteria?

A

Above diaphragm - gram positive anaerobe > finegoldia, susceptible to beta lactams

Below diaphragm - gram negative anaerobe > B fragilis, require specific Abx

and there is the problem child: C diff

117
Q

When to initiate Abx treatment for bacterial rhinosinusitis?

A
  1. Persistent symptoms beyond 10 days with no clinical improvement
  2. Symptoms worsen
  3. Symptoms clinically improvement for >=3 days but gets worse again (double sickening)
118
Q

First line treatment for bacterial sinusitis

+ penicillin allergy
+ duration of treatment

A

Amoxicillin 500mg Q8H
Amoxicillin-Clavulanate 625mg Q8H (improved susceptibility of H influenzae in case of resistance)

Penicillin allergy:
- non severe - PO cefuroxime
- PO Levofloxacin 500mg or moxifloxacin 400mg OD

Duration of therapy: 5-7days

119
Q

Which group of patients should be recommended pre-treatment blood and respi gram stain and cultures in pneumonia (CAP)?

A

Severe CAP
Risk factors for Drug resistant pathogens (MRSA, PsA) aka empirically treated for MRSA/PsA OR previously infected with MRSA/PsA in past 1 year OR Hospitalised/received parenteral abx in last 90 days

120
Q

Key pathogens in outpatient and inpatient non severe CAP cases

A
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Atypical (Legionella, Mycobacterium, Chlamydophila pneumoniae)
  • inpatient: MRSA and PsA risk factors
121
Q

Key pathogens in inpatient severe CAP

A
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Atypical (Legionella, Mycobacterium, Chlamydophila pneumoniae)
  • Staphylococcus aureus
  • Gram negative bacilli (Klebsiella pneumoniae)
    *** Burkholderia pseudomallei
  • inpatient: MRSA and PsA risk factors
122
Q

What is involved in CURB-65 criterion for CAP severity?

A

Confusion (new onset)
Urea > 7mmol/L
Respiratory rate >= 30 breaths/min
Blood pressure (<=90mmHg or <=60mmHg)
>= 65 years

0-1: outpatient
2: inpatient
>=3: inpatient, consider ICU

123
Q

How to determine Severe CAP? by IDSA/ATS

A

> = 1 major criterion OR >= 3 minor criterion

Major:
- mechanical ventilation
- septic shock requiring vasoactive medications to maintain BP

Minor:
- RR>=30bpm
- PaO2/FiO2 <= 250
- multilobar infiltrates
- confusion/disorientation
- uremia (urea>7mmol/L
- leukopenia (WBC < 4x10^9/L)
- hypothermia (<36degC)
- hypotension requiring aggressive fluid resuscitation

124
Q

First line outpatient CAP treatment

ALL PO ABX

A

No comorbidities: (just need cover strep pneumo) Amoxicillin 1g Q8H OR respiratory FQ

with comorbidities: (cover all)
Amoxicillin-clavulanate OR cefuroxime AND
macrolide (clarithro/azithro) or doxycycline (for atypical coverage)
OR respiratory FQ - cover everyth

125
Q

Empiric treatment for inpatient non severe CAP

A

same as outpatient comorbidities

Amoxicillin-clavulanate OR cefuroxime OR ceftriaxone (IV option avail in hospital) AND
macrolide (clarithro/azithro) or doxycycline (for atypical coverage)
OR respiratory FQ - cover everyth

MRSA Risk factor: (Resp isolation of MRSA in last 1 year / hospitalisation or parenteral abx use in last 90 days + positive MRSA PCR screen)
ADD ON IV VANCOMYCIN / PO/IV LINEZOLID

PsA risk factors (Resp isolation of PsA in last 1 year)
MODIFY REGIMEN to incl PsA
- Pip-taz (no atypical)
- Ceftazidime (no strep pneumo)
- Cefepime (no atypical)
- Meropenem (not good atypical)
- Levofloxacin (alone is ok! But tb….)

126
Q

Empiric treatment for inpatient severe CAP

A

(cover incl SA and burkholderia - ceftazidime)

Amoxicillin-clavulanate/Penicillin G + ceftazidime + macrolide (clarithro/azithro)
OR respiratory FQ + ceftazidime
(MSSA incl in amox/clav, cefta incl burkholderia and H inf, no strep pneumo, macrolide for atypicals)

MRSA risk factors (resp isolation in last 1 year OR hospitalised/parenteral abx use in last 90 days)
ADD IV VANCOMYCIN / PO/IV LINEZOLID

PsA risk factors (resp isolation in last 1 year OR hospitalised/parenteral abx use in last 90 days)
cover PsA but ceftazidime / levofloxacin already cover

127
Q

How to de-escalate CAP treatment after patient has stable vitals and clinical improvement?

A

Can stop empiric coverage for MRSA, PsA and burkholderia if pathogen is not isolated and patient is improving

128
Q

Treatment duration for CAP

A

min 5 days, 7 days for suspected/proven MRSA/PsA

129
Q

Likely pathogens for HAP/VAP

A

PsA
enterobacterales (ecoli, klebsiella, proteus)
Staphylococcus aureus

130
Q

In HAP/VAP, under what conditions/risk factors should we cover MRSA?

A
  • prior IV abx use in last 90 days
  • isolation of MRSA in last 1 year
  • hospitalisation in unit where >20% of S aureus are MRSA
  • prevalence not known but patient high risk of mortality (need mechanical ventilation for eg)
131
Q

When to use double antipseudomonal agent for HAP/VAP?

A
  • risk factors for PsA (prior IV abx use in last 90 days, isolation in last 1 year, acute RRT prior VAP onset)
  • hospitalisation in a unit where >10% of PsA isolates are resistant to an agent considered for monotherapy
  • prevalence not known but high risk mortality
132
Q

Why cannot use amikacin (aminoglycosides) as sole antipseudomonal agent?

A

Cannot reach high enough concentrations and shown to be inferior as monotherapy for PsA

monotherapy for UTI is ok tho, can reach kidney and UT

133
Q

empiric treatment for HAP/VAP

A

(cover enterobacterales, PsA, staph aureus)

  1. antipseudomonal beta-lactam (Pip-taz, cefepime, meropenem, imipenem, ceftazidime[no SA coverage, use only if MRSA cover is needed])
  2. (if double PsA coverage) antipseudomonal FQ - levofloxacin or ciprofloxacin[no SA coverage, use only if MRSA cover is needed])
    OR
    amikacin (aminoglycoside) - cannot for sole agent

MRSA cover:
IV VANCOMYCIN OR IV/PO LINEZOLID (can use cefta&cipro since vanco/linezolid cover SA)

134
Q

How to de-escalate in HAP/VAP?

A

Positive cultures for PsA –> cut to 1 agent

No positive cultures, keep covering for MSSA, PsA and gram neg bacilli
- go according to local antibiogram (choose those with higher susceptibility >90)

135
Q

Duration of treatment for HAP/VAP

A

7 days regardless of pathogens

136
Q

Classic triad of symptoms for bacterial meningitis

A

headache
backache
nuchal/neck rigidity

137
Q

Most likely organisms in bacterial meningitis for

neonates (<1mth)
infants and children (<23mths)
children and adults (2-50)
adults (>50 year)

A

Neonates:
Group B streptococcus (Strep agalactiae), E. coli, Listeria monocytogenes

Infants and Children:
S. agalactiae, E coli,
Strep pneumoniae, Neisseria meningitidis

Children and adults:
S pneumoniae, N meningitidis

Adults:
S pneumoniae, N meningitidis, Listeria monocytogenes, aerobic GNR (e coli, klebsiella)

138
Q

Empiric treatment for bacterial meningitis in

neonates (<1mth)
infants and children (<23mths)
children and adults (2-50)
adults (>50 year)

A

Neonates:
Ceftriaxone + ampicillin (covers Listeria)

Infants and children:
Ceftriaxone + vancomycin (increasing resistance of S pneumo to ceftriaxone, add vanco to be safe and eradicate S pneumo)

Children and adults:
Ceftriaxone + vancomycin

Adults:
Ceftriaxone + vancomycin + ampicillin

139
Q

Treatment duration for

S pneumo
N meningitidis
L monocytogenes
S agalactiae (Group B strep)
Culture-negative

A

S pneumo - 10-14 days
N meningitidis - 5-7 days
L monocytogenes - more than 21 days
S agalactiae (Group B strep) -14-21days
Culture-negative - at least 14 days (may extend, see condition)

140
Q

For which bacteria (2) is adjunctive dexamethasone therapy effective for in bacterial meningitis? + benefits

A

H influenzae and S pneumoniae

  • less hearing loss and other neurologic sequelae
  • decreased mortality in S pneumoniae
141
Q

Close contact prophylaxis for neisseria meningitidis

A

preferred: rifampicin PO

other options:
- ciprofloxacin - risk of CNS toxicity (not preferred if meningitis)
- ceftriaxone IM - painful and inconvenient

142
Q

Definition of watery diarrhoea in CDI

A

more than or equal to 3 stool in 24h

143
Q

Diagnosis of CDI

A

presence of diarrhoea OR radiographic imaging of ileus or toxic megacolon

AND

positive stool test (only done for suspected CDI) OR colonoscopic/histopathologic evidence of pseudomembranous colitis

144
Q

Initial episode treatment of CDI

Non severe
Severe
Fulminant

A

Non severe: PO fidaxomicin (but not avail in SG)

1st line: PO vancomycin 125mg QDS

2nd line: PO metronidazole 400mg TDS (gets well slower; SE is diarrhea)

Severe: PO vancomycin 125mg QDS

Fulminant: IV metronidazole 500 q8h AND PO vancomycin 500mg QDS +/- PR vancomycin 500mg QDS

symptoms should resolve in 10 days, if not extend 4 days

145
Q

recurrent episode treatment of CDI

A

if was on fidaxomicin/vancomycin:
Tapered/pulsed PO vancomycin

if was on Metronidazole:
PO vancomycin 125mg QDS x 10 days

2nd or subsequent recurrence: pulse/tapered PO vancomycin or fecal microbiota transplant

146
Q

legally notified STDs

A

gonorrhea, syphilis, HIV/AIDS, chlamydia, viral hepatitis

147
Q

Gonorrhea treatment

Need to treat with chlamydia unless ruled out already

A

Ceftriaxone 500mg IM (give with lignocaine) (If >150kg, give 1g) single dose
for CHLAMYDIA: doxycyline 100mg BD x 7 days

alternate:
Gentamicin 240mg IM single dose + azithromycin 2g PO single dose (for chlamydia)

& also cefixime but not avail in sg

148
Q

Chlamydia treatment

A

doxycycline 100mg BD x 7 days

alternative/less-adherent option: azithromycin 1g PO single dose

alternative: Levofloxacin 500mg PO OD x 7 days (ONLY FQ that can be used; caution in monotx for TB)

149
Q

Syphilis treatment in:

  • Primary, Secondary or early latent (<1 year)
  • unknown duration/late latent infection/tertiary
  • neurosyphilis
A

Primary, Secondary or early latent (<1 year):
IM benzathine Penicillin G 2.4 MU x 1 dose

alternative: PO doxycycline 100mg BD x 14 days

unknown duration/late latent infection/tertiary:
IM benzathine penicillin G 2.4 MU once a week x 3 dose
OR
PO doxycycline 100mg BD x 28 days

Neurosyphilis:
IV crsytalline penicillin G 3-4 MU Q4H OR 18-24million units/day continuous infusion
OR
IM procaine penicillin 2.4 MU OD + PO Probenecid 500mg OD x 10-14 days
OR
IV/IM ceftriaxone 2g OD x 10-14days

150
Q

Benefits of PO acyclovir and valacyclovir as antiviral treatment for genital herpes?

A
  • Reduce viral shedding (by 7 days)
  • Reduce duration of symptoms (by 2 days)
  • Reduce time of healing of 1st episode (by 4 days)
  • Inhibits viral DNA polymerase → inhibits DNA synthesis and replication
151
Q

First episode genital herpes treatment

A
  • PO acyclovir 400mg TDS x 7-10days OR IV 5-10mg/kg Q8H x 2-7days if severe
  • PO valacyclovir 1g BD x 7-10days

maintain adequate hydration to prevent crystallisation in renal tubules.
main SE: headache

152
Q

Chronic suppressive therapy options for genital herpes

A
  • PO acyclovir 400mg BD
  • PO valacyclovir 500mg OD (maybe less effective)
  • PO valacyclovir 1g OD
  • famciclovir (not avail in sg)
153
Q

Episodic therapy options for genital herpes

A

Acyclovir 800mg PO BD x 5 days OR
Acyclovir 800mg PO TDS x 2 days OR
Valacyclovir 500mg PO BD x 3 days OR
Valacyclovir 1g PO OD x 5 days

need to initiate within 1 day of symptom onset, best during prodrome period

154
Q

Measurement of surrogate markers in HIV/AIDS

A
  • viral load
    before initiation of therapy and within 2-4weeks (not more than 8)
    and every 4-8 weeks until suppressed viral load
    stable patients: can measure every 3-6months or longer
  • CD4 count
    measure @ baseline and every 3-6months after start treatment & every 12 months after adequate response (aka CD4 between 50-150 in first year of therapy)
155
Q

HIV/AIDS meds (4)

A
  • Biktarvy (3in1) – bictegravir (INSTI) + tenofovir (NRTI) + emtricitabine (NRTI)
  • Dolutegravir (INSTI) + tenofovir + emtricitabine
  • Triumeq (3in1) – dolutegravir + abacavir (NRTI) + lamivudine (NRTI)
  • Dovato (2in1) – dolutegravir + lamivudine → only for individuals w HIV RNA < 500,000copies/ml + no evidence of Hep B coinfection

PR3151 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions