doses of abx Flashcards
urine culture for
complicated UTI
1) Preg
2) Recurrent UTI (relapse within 2wks/ freq)
3) Pyelonephritis
4) Catheter-associated Uti
5) MEN with UTI
NOT: uncomplicated cystitis/ ASB
uncomplicated cystitis first lines
fosfomycin 3g (1dose)
nitrofurantoin 50mg QDS (5d)
CMX 960mg BD (3d)
uncom cys 2nd line
beta-lactams 5-7d
amox-clav 625mg BD
cefuroxime 250mg BD
cephalexin 250mg QDS
pen allergy uncom cys
FQ 3d
ciprofloxacin 250mg BD
levofloxacin 250mg OD
uncomplicated pyelo PO
PO CMX 960mg BD (10-14d)
PO cipro 500mg BD (7d)
PO levo 750mg OD (5d)
severely ill pyelo IV
IV cipro 400mg BD
IV amoxicillin-clav 1.2g TDS +/- gentamicin 5mg/kg/d
IV cefazolin 1g TDS +/- gentamicin 5mg/kg/d
uncomplicated pyelo beta-lactams
10-14d
amox-clav 625mg TDS
cefuroxime500mg BD
cephalexin 500mg QDS
complicated cystitis
fosfomycin 3g (EOD 3dose)
nitrofurantoin 50mg QDS (7-14d)
CMX 960mg BD (7-14d)
risk of prostatitis, men with myelo
PO CMX 960mg BD (10-14d)
PO ciprofloxacin 500mg BD (10-14d)
HAI-UTI risk factors
UTI after >48hr hospitalisation
Pt hosp last 6mnths
Invasive urological procedure last 6mnths
Indwelling urine catheter
HAI-Pyelo PO
PO cipro 500mg BD (7-14d)
PO levo 750mg OD (7-14d)
HAI-Pyelo IV M4
IV meropenem 1g TDS
IV imipenem 500mg QDS
IV cefepime (2g BD) +/- amikacin 15mg/kg/d
Catheter-UTI PO
PO CMX 960mg BD (3d)
PO levofloxacin 750mg OD (5d)
PO CMX for CAT UTI when
Treat of women PO CMX:
= 65 y/o CA-UTI
without upper UTI symptoms -
after removal of catheter
CAT-UTI IV ML4
IV levo 750mg OD (7d)
IV meropenem 1g TDS (7d)
IV imipenem 500mg QDS (7d)
IV cefepime (2g BD) +/- amikacin 15mg/kg/d (7d)
(7d. defeverse in 72hrs. 10-14d if delayed response)
symptomatic relief UTI
Phenazopyridine 100-200mg TDS
impetigo (staph, strep)
TOP muciporin BD 5d
ecthyma – strep A
(7d)
PO cloxacillin 500mg QDS
PO cephalexin 500mg QDS
MSSA: cloxacillin, cephalexin, clindamycin
S.pyogenes: pen V 500mg BD, amoxicillin 500mg TDS
PURULENT SSTI, MILD, MOD, SEVERE CLASSIFICATION
MILD -
MOD - systemic sx
SEVERE - age, immunosupp, more severe systemic, failed I&D
CA MRSA
Contact (sports, military, IV drug abuse, prison)
Overcrowded facilities, close contact, lack sanitation
PURULENT SSTI – staph aureus, grp B strep
MILD
(5-10d)
MILD: I&D + warm compress
PURULENT SSTI – staph aureus, grp B strep
MODERATE
MOD: I&D + PO cloxacillin 500mg QDS, cephalexin 500mg QDS, PO clindamycin 300-450mg QDS
PURULENT SSTI – staph aureus, grp B strep
SEVERE
SEVERE: I&D + IV cloxacillin 500mg-1g QDS, IV cefazolin 1-2g TDS, IV clindamycin 600mg TDS, IV vancomycin 15mg/kg Q8-12H
PURULENT SSTI ADD-ONS COVER FOR___
CA MRSA: doxy (100mg BD), clindamycin (300-450mg QDS), CMX 960mg BD
HA MRSA: IV vancomycin 15mg/kg Q8-12H, daptomycin 4-6mg/kg/d, linezolid 600mg BD
ANAEROBE: amox-clav 625mg TDS
HA MRSA
MRSA infection/colonization in last 12 months
prolonged/repeated hospital stay in the last 12 months,
hemodialysis.
anaerobe, GN bacilli
skin abscess in perioral/ perirectal/ vulvovag area
risk factors for less common pathogen in non purulent
Aeromonas, vibrio vulnificus, pseudomonas with water exposure
what classify as MILD, MOD, SEVERE NON-PURULENT SSTI
mild: no systemic sign
mod: systemic signs + purulence
*MSSA cover
severe: systemic sign of infeciton, failed PO, immunocompromised.
* broader coverage, necrotising infection
NON-PURULENT SSTI MILD
(5-10d, 14d for immunocomp)
MILD (strep pyogenes)
PO pen V 250mg QDS
PO cephalexin 500mg QDS
Po cloxacillin 500mg QDS
Po amoxicillin 500mg TDS
PO clindamycin 300-450mg QDS
NON-PURULENT SSTI
MOD (MSSA)
(MSSA cover):
IV cefazolin 1-2g TDS
IV clindamycin (600mg TDS)
NON-PURULENT SSTI SEVERE
(necrotising, anaerobe cover): MP4
IV meropenem 1g TDS
IV imipenem 500mg QDS
IV pip-tazo 4.5mg IV TDS
IV cefepime 2g TDS
ADD-ONS FOR NON-PURULENT SSTI
+/- MRSA:
IV vancomycin 15mg/kg Q8-12H
daptomycin 4-6mg/kg/d,
linezolid 600mg BD
common DFI bact
staphylococcus aureus
streptococcus spp
anaerobes in DFI when
peptostreptococcus spp, veilonella spp, bacteriodes spp
Anaerobes (ischemia, necrotising wound)
GN bacilli eg and when to tx
e.coli, kleb spp, proteus spp, pseudo less common
Gram neg bacilli (chronic wounds, previous tx with AB)
pseudo cover in DFI
Warm climate, exposure to water
Empiric cover
( for severe infection// failure of Abx)
DFI/ PU (staph aures, strep spp)
MILD
1-2wks if no bone involved
PO cloxacillin 500mg QDS,
POcephalexin 500mg QDS
PO clindamycin (300-450mg QDS)
MILD DFI MRSA
if MRSA USE INSTEAD: PO doxy (100mg BD), clindamycin (300-450mg QDS), CMX 960mg BD
DFI SEVERE MPC3,4
strep, staph aures, GN (pseudo), anaerobe
SA, strep, GNB, anaerobe
2-4wks if no bone involved
IV meropenem (1g TDS)
IV imipenem (500mg QDS)
IV pip-tazo (4.5g TDS)
IV Ciprofloxacin (400mg BD)+ IV clindamycin (600mg TDS)
IV cefepime (2g TDS)+ IV metronidazole (500mg TDS)
DFI MOD (AXONE)
strep, staph aureus, GN (+/- pseudo) , anaerobes
1-3wks if no bone involved
IV ampicillin-clav 1.2g TDS
IV ceftriaxone (1-2g OD-BD)+ metronidazole (500mg TDS)
IV cefazolin (1-2g TDS) + metronidazole (500mg TDS)
influenza risk of complications in
Child <5// elderly >65
Preg/ 2wks post-partum
Nursing homes/ LT care
Obese BMI > 40kg/m2
Chronic medical conditions
Asthma, COPD, HF, DM, CKD, immunocompromised
DFI MOD / SEVERE + MRSA
IV vancomycin 15mg/kg Q8-12H
daptomycin 4-6mg/kg/d
linezolid 600mg BD
bone involvement duration
amputate 2-5 days
residual soft tissue 1-3wk
residual viable bone 4-6wk
no surgery/ residual dead bone > 3mnths
common cold
self-limiting 7-10 days
post-nasal drip 2-3wks.
feel better in 3-4d, but sx linger
influenza
PO oseltamivir 75mg BD (5d)
modified centor criteria
FLECA
fever, swollen lymph, exudate tonsils, no cough, 3-14 yrs
> 2 pts throat test for Grp A strep
pharyngitis - strep pyogenes PAZI 1
(10d, sx 1-2d)
pen V 250mg QDS
amox 500mg BD
cephalexin 500mg BD
azithromycin 500mg OD (5d)
clarithromycin 250mg BD
clindamycin 300mg TDS
incr strep pneumo resistance (change in PBP)
cannot use which Abx
CMX
MACROLIDES
TETRACYCLINES
use amox high dose
when to treat rhinosinusitis
=/>1
1) Symptoms persists > 10 days w/o clinical improvement
2) Symptoms severe
- Fever > 38*C
- Purulent nasal discharge
- Facial pain > 3 days consecutive
3) Symptoms worsen after initial improvement
*double sickness! (improve for 3 days or worsen (5-6 days)
-New-onset fever
-Headache
-Incr nasal discharge
prevent what with Abx tx in pharyngitis
Acute rheumatic fever
Prevented with early initiation of effective AB
Acute glomerulonephritis
Not prevented by AB
LRTI duration
CAP: 5d min, 48-72hr for clinical stability
elderly take longer, do not escalate in 72hrs
7d: risk MRSA, PSEUDO
3-6wk: burk
6mn TB
HAP/VAP: 7 day min
48-72hr clinical stability, delay 4-5d if comorbidities
rhinosinusitis - strep pneumo, h influ
MALA2
(5-7d course, but 7-10d to improve)
cefuroxime 500mg BD
amox 500mg TDS
amox-clav (h.influ) 625mg TDS
moxi 400mg OD (5-7d)
levo 500mg OD (5-7d)
bronchitis
self limit in 3wks, Abx does not resolve cough
CAP outpt, no comrbities – strep pneumo
PO amoxicillin 1g TDS
PO levo 750mg OD (5d)
comorbidities
Chronic heart, lung, liver, renal disease
DM
Alcoholism
Malignancy
Asplenia
CAP outpt, comorbidities – strep pneumo, H influ, atypicals
3 classes
beta-lactams
PO amoxicillin 1g TDS
PO cefuroxime 500mg BD
+
macrolides
clarithromycin 500mg BD
azithromycin 500mg OD
DOXYCYCLINE 100mg BD
OR: PO levofloxacin 750mg OD
CAP non severe inpt – strep pneumo, H influ, atypicals, INFLUENZA
beta-lactams
PO/IV amox-clav 625mg TDS/ 1.2g TDS
PO cefuroxime 500mg BD
IV ceftriaxone 1-2g OD
+
macrolides
clarithromycin 500mg BD
azithromycin 500mg OD
DOXYCYLCINE 100mg BD
OR: levofloxacin 750mg OD
Pre-treatment blood and resp gram-stain and culture for pt in hosp:
- Severe CAP
- Risk factors for drug-resistant pathogens (MRSA, pseudo)
1) Being empirically tx for MRSA, pseudo
(VAP/ HAP)
2) Previously infected with MRSA or Pseudo in last 1 year
3) Hosp or IV Abx in last 90d
CAP non severe inpt ADD-ONS
+/- MRSA:
vanco (25-30mg/kg LD, 15mg/kg Q8-12H),
linezolid 600mg BD
+/- PSEUDO: MPL3,4
PO/ IV levo 750mg OD
IV meropenem 1g TDS
IV imipenem 500mg QDS
IV pip-tazo 4.5g TDS
IV ceftazidime 2g TDS
IV cefepime 2g TDS
influenza: Oseltamivir 75mg BD 5d
CAP non severe inpt MRSA cover when
Resp isolation of MRSA in last 1 yr
hospitalisation/ IV Abx use in last 90d + MRSA PCR screen +ve
CAP non severe inpt pseudo cover when
Pseudo risk factors
Resp isolation of pseudo in last 1 yr
(MPL3,4)
CAP non severe anaerobic cover when
Radiology investigation (CXR, CT scan for lung abscess, empyema)
severe CAP IDSA
Major criteria (any 1)
- Mechanical ventilation
- Septic shock require vasoactive medications (haemodynamic instability)
Minor criteria (>3)
- RR >30breath/min
- PaO2/ FiO2 < 250
- Multilobar infiltrate (extensive infection)
- Confusion/ disorientation (Elderly tho..)
- Uremia (urea>7 mmol/L)
- Leukopenia (WBC <4/L), Must not be from other causes, chemo etc
- Hypothermia (<36*C)
- Hypotension, aggressive fluid resuscitation
CAP severe
strep pneumo, H influ, atypicals, staph aureus, GNB (kleb, e.coli, pseudo), burkholderia, INFLUENZA
beta-lactams
IV amox-clav 1.2g TDS
IV pen G 1-3g Q4-6H ***
+ CEFTAZIDIME 2g TDS
+ macrolides
azithromycin 500mg OD
clarithromycin 500mg BD
OR: IV levofloxacin 750mg OD + IV ceftazidime 2g TDS
CAP severe inpt add ons
+/- MRSA: vanco, linezolid
psuedo covered by ceftazidime, levo
influenza: Oseltamivir 75mg BD 5d
Adjunct corticosteroid therapy
when cover burkholderia pseudomallei
Severe CAP in tropical countries – ceftazidime
severe CAP inpt MRSA risk factors
Resp isolation of MRSA in last 1 yr
hospitalisation/ IV Abx use in last 90d
CAP abscess found when
Radiology investigation (CXR, CT scan for lung abscess, empyema)
severe CAP pseudo risk factors
Resp isolation of pseudo in last 1yr
Hosp or IV Abx use in last 90d
CAP anaerobe tx
PO/IV metronidazole 500mg QDS-BD/ PO 400mg TDS)
CLINDAMYCIN (PO 300-450mg QDS) (IV 600mg TDS)
when double pseudo cover
Antimicrobial resistance
1) Prior IV abx use within 90d
2) Acute renal replacement therapy prior to VAP onset
3) Isolation of Pseudo in last 1 year
Hosp in a unit where >10% of pseudo are resistant to an agent being considered for monotherapy
Prevalence of pseudo no known
* But pt high risk of mortality
* Need for ventilatory support due to HAP & septic shock
Adjunct corticosteroid therapy added when
Shock refractory to fluid resuscitation and vasopressor support
No benefit in non-severe CAP
Prednisolone (PO), dextromethorphan, hydrocortisone (IV)
when VAP/HAP need MRSA cover
1) Prior IV Abx use in last 90d
2) Isolation of MRSA in last 1yr
3) Hosp in unit where >20% of SA is MRSA
4) Prevalence of MRSA in hosp unknown
- But pt high risk for mortality
- Need for ventilatory support due to HAP and septic shock
VAP/HAP tx
pseudo cover
beta-lactamas MPL3,4 (meropenem, imipenem, piptazo, ceftazidime, cefepime)
FQ (cipro, levo)
AG (amikcain, gentamicin)
MRSA cover
linezolid
vancomycin
Listeria monocytogenes found where?
Gram +ve, intracellular rod bact
○ found in moist environ, soil, water
○ Food borne (replicates in refrigerator temp – cold deli meats, unpasteurized dairy pdt)
- Infect young, old!
bacterial meningitis neonates covers what pathogen using which Abx?
strep B, listeria, e.coli
ceftriaxone 2g BD
ampicillin 2g Q4H
child 1mn-23mn
strep B, e.coli, strep pneumo, neisseria
ceftriaxone 2g BD
vancomycin 25-30mg/kg (KD), 15mg/kg/h (Q8-12H)
2-50yo:
strep pneumo, neisseria
ceftriaxone 2g BD
vancomycin 25-30mg/kg (KD), 15mg/kg/h (Q8-12H)
> 50yo
strep pneumo, neisseria, listeria, e.coli
ceftriaxone 2g BD
vancomycin 25-30mg/kg (KD), 15mg/kg/h (Q8-12H)
ampicillin 2g Q4H
culture-directed
Neisseria meningiditis
5-7d
pen G IV 4 MU, Q4H, ampicillin 2g Q4H
ceftriaxone 2g BD
culture-directed for Strep pneumo (meningitis)
10-14d
pen V IV 4 MU, Q4H
ampicillin 2g Q4H
ceftriaxone 2g BD
VANCOMYCIN (25-30mg/kg LD, 15mg/kg Q8-12H)+ RIFAMPICIN IV 300mg BD
culture directed for strep B
14-21d
pen V IV 4 MU, Q4H, ampicillin 2g Q4H
ceftriaxone 2g BD
culture directed for Listeria monocytogenes
< 21d
pen V IV 4 MU, Q4H, ampicillin 2g Q4H
CMX 5mg/kg TDS
MEROPENEM 2g TDS
add-on for bacterial meningitis
dexamethasone 10mg QDS (4d)
H.Influenzae & strep pneumoniae meningitis
1) prevent Abx inflammation
2) Less hearing loss and other neurological sequelae
3) Decr mortality in strep pneumoniae meningitis
Chemoprophylaxis using 3
rifampicin PO
Ciprofloxacin PO
ceftriaxone IM
when admin dexamethasone
Administer 10-20mins before/ same time as 1st dose of Abx
beyond neonatal age (>6wks)
rifampicin PO
adult 600mg/kg bd (4 dose)
child 10mg/kg bd (4 dose)
neonate 5mg/kg bd (4 dose)
ciprofloxacin PO
adult 500mg (1dose)
ciprofloxacin PO (meningitis prophylaxis)
adult 500mg (1dose)
ceftriaxone IM
adult: 125-250mg (1dose)
CDI non severe labs
WBC <15 x10*9
& SCr <133umol/L
CDI non-severe
first ep
PO vancomycin 125mg QDS
PO metronidazole 400mg TDS
10-14d
CDI severe
first ep
PO vancomycin 125mg QDS
10-14d
CDI fulminant
first ep
IV metronidazole 500mg TDS
+/- PO vancomycin 500mg QDS
+/- PR vancomycin 500mg QDS
CDAD recurrence risk factors
Resolution of CDI sx, subsequent reappearance of sx after tx discontinued
1) other Abx during/ after initial Tx of CDI
2) defective humoral immune response
- Age
- underlying disease
3) Continued use of PPI
recurrent CDI use metronidazole first
PO vancomycin 125mg QDS 10-14d
recurrent
use fidoxacin, vancomycin first
PO vancomycin tapered/ pulsed (6-12wks)
125mg QDS 10-14d
125mg BD 7d
125mg OD 7d
125mg every 2-3daysx 2-8wks
STI:
gonorrhea
GONE AH
ceftriaxone 500mg IM (1 dose) — 1g IF >150KG
gentamicin 240mg IM + azithromycin 2g PO
add on for gonorrhea
chalmydia cover: PO doxycycline 100mg BD 7d
chalmydia DAL
doxy 100mgadd-on for g BD 7d
azithromycin 1g PO
levofloxacin 500mg OD 7d
syphilis
1,2, early latent <1yr
IM pen G 2.4 MU 1dose (benzathine)
PO doxycycline 100mg BD 14d
syphilis
3*, late latent >1yr, unknown
IM pen G 2.4 MU 3dose (benzathine )
PO doxycycline BD 28d
neurosyphilis
IV crystalline pen G 3-4 MU (18-24 Q4H) 10-14d
IM procaine pen G 2.4 MU + PO probecenid 500mg QDS 10-14d
IV/IM Ceftriaxone 2g OD (10-14d) —- Desensitise if penicillin allergy
herpes
1st epi
acyclovir
400mg TDS 7-10d
IV 5-10mg/kg TDS 2-7d then PO for 10d
valacyclovir
PO 1g BD 7-10d
CST herpes
acyclovir 400mg BD
valacyclovir 1g OD
or 500mg OD (if less freq >10/yr)
episodic herpes
Acyclovir 800mg PO BD 5d
800mg TDS 2d
Valacyclovir 500mg BD 3d
1g OD 5d
STI diagnosis
Gonorrhea:
1) Gram stain of genital discharge
2) Culture – Get AST for resistance strains
3) NAAT
Chlamydia:
1) NAAT
Syphilis:
1) Darkfield microscopy
2) Serological test
Herpes
1) Virologica test (viral cell culture, NAAT)
2) Type specific serologic test
—- 6-8wks ltr HSV 1/ 2
HIV diagnosis
1) Serum Ab detection
- HIV enzyme immunoassay Ab test
HIV EIA tests
- Western blot
2) HIV RNA detection/ quantification (viral load)
- Nucleic acid amplification (PCR)
HIV response monitored through
1) CD4
Incr 50-150 in 1st year of therapy
2) Viral load (HIV RNA)
Nucleoside reverse transcriptase inhibitors (NRTIs)
Tenofovir
Emtricitabine
Abacavir
Lamivudine
Zidovudine
HIV NRTI DISADV
ADR related to mitochondrial toxicity (Z>T>A> L)
* Rare but serious
* Lactic acidosis
* Hepatic steatosis (fatty infiltrate)
* Lipoatrophy (Loss of fat)
Require dose adjustment in renal impaired pt
* Except abacavir
HIV NRTI ADV
- Established dual backbone of combi ART (2NRTI)
- Renal elimination, less DDI concerns
TEZLA SE
- Tenofovir (NVD, renal. BMD)
- Emtricitabine (Hyperpigmentation, ND)
- Zidovudine (Myopathy, Bone marrow supp)
- Lamivudine (Minimal toxicity, NVD)
- Abacavir (NVD, Hypersensitivity reaction HLAB*5701)
INSTI
Bictegravir
Dolutegravir
Raltegravir
Elvitegravir
INSTI ADVANTAGE
1) Bictegravir & Dolutegravir
* Good virologic effectiveness
2) High genetic barrier to resistance
* B/D > R/E
3) Well tolerated
NNRTI
Efavirenz
Rilpivirine
INSTI DISADV
Bioavailability lowered by concurrent ad of polyvalent cations (Ca, Fe)
B,D,E are CYP3A4 substrates
Weight gain, ND, headache, depression, suicidality
INSTI BRED SE
Bictegravir (Scr)
Raltegravir (CK, rhabdo)
* Pyrexia (fever)
Dolutegravir (Scr)
NNRTI DISADV
Low genetic barrier to resistance
Cross resistance among approved NNRTIs
Skin rash, SJS (E>R)
Potential for CYP450 drug interactions
QTc prolongation
NNRTI ADVANTAGE
- Long half life (daily dosing)
- Less metabolic toxicity
RILFAV SE
Rilpivirine (Depression, headache, SJS)
Efavirenz (hepatotox, hyperLDL, neuropsy)
Mixed CYP inducer/ inhibitor in RILFAV (NNRTI)
E: CYP3A4 sub
○ CYP2B6, 2C19 inducer
R: CYP3A4 sub
○PO ab reduced when incr pH (no PPI)
PI
Ritonavir
Lopinavir
Atazanavir
Darunavir
Fosamprenavir
(ritonavir/ cobicistat)
PI ADVANTAGE
FARDL
High genetic barrier to resistance
* Esp those with high viral load, risk mutation
PI resistance is less common
PI DISADV
Liver toxicity (if hep B,C)
DDI: CYP3A4 inhibitors, substrates
Metabolic complications (LDL, insulin)
GIT (NVD)
Lipohypertrophy, fat maldistribution
Incr risk of osteopenia/ osteoporosis
FARDL SE
Atazanavir (less GI, lipid effect, need LOW ab, skin rash, hyperbilirubin, QT)
Ritonavir (CYP3A4, 2D6i)
* Freq combined with other PI, boost lvl (Lopinavir/ ritonavir)
SE: paresthesia (numb in extremities), taste perversion
Darunavir (less lipid, SJS)
(sulphonamide)
Fusion inhibitors
Enfuvirtide
CCR5 antagonist
Maraviroc
Enfuvirtide ADVANTAGE AND DISADV
No appreciable DDI
Inj site reaction
Rare hypersensitivity reaction
(Fever, chill, decr BP)
Incr bacterial pneumonia
Maraviroc DISADVANTAGE
CYP3A4 substrate
Abdominal pain
Cough
Dizziness
Musculoskeletal sx
Pyrexia
Rash
Upper resp tract infections
Hepatotoxicity
Orthostatic hypotension
