ABX specific Flashcards
1st gen cephalosporins
name 2 of them
Cephalexin
Cephazolin
what class
Cephalexin
Cephazolin
1st gen cephalosporins
what are 1st gen cephalosporins used in
Cephalexin
Cephazolin
Skin and UTI
Prophylaxis to prevent infections from surgical repair
specific organisms 1st gen cephalosporins treat
Gram + (skin)
-Streptococci
-Staphylococci that are not B lactamase
Gram - (UTI)
-Proteus Mirabelis
-E.Coli
-Klebsiella pneumoniae
Name 4 of the 2nd gen cephalosporins
Cefuroxime
Cefotetan
Cefoxitin
Cefaclor
what drug class?
Cefuroxime
Cefotetan
Cefoxitin
Cefaclor
2nd gen cephalosporins
What do 2nd gen Cephalosporins treat
Increased resistance to B lactamase as opposed to 1st gen
These have better gram - coverage than 1st gen
Also 2 in this class have anaerobic coverage
Cefotetan and Cefoxitin
Gram -
H. Influenzae
Serratia Marcescens
Enterobacter aerogenes
Some Neisseria
Only Cefotetan and Cefoxitin can treat anaerobic (Bacteroides Fragilis ->Peritonitis)
what 2nd gen Cephalosporins can treat the anaerobic bacteria seen in Peritonitis (Bacteroides Fragilis)
Cefotetan
Cefoxitin
what 3 generations of cephalosporins are considered Broad Spectrum
3rd generation
-Cefixime
-Ceftriaxone
-Cefaxime
-Ceftazidime
4th Gen
-Cefepime
5th gen
Ceftaroline
what 2 generations of cephalosporins can cross the BBB
3rd generation
-Cefixime
-Ceftriaxone
-Cefaxime
-Ceftazidime
4th Gen
-Cefepime
what antibiotics are 3rd gen cephalosporins
-Cefixime
-Ceftriaxone
-Cefaxime
-Ceftazidime
what med class
-Cefixime
-Ceftriaxone
-Cefaxime
-Ceftazidime
3rd gen cephalosporins
As you get further into the generations of cephalosporins, how does the coverage change
1st gen has the most gram + coverage
least amount of gram -
3rd and 4th are broad spectrum, however 4th has less coverage against gram + and increased coverage for gram -
however 4th gen is broader than 3rd gen
What does 3 rd gen cephalosporins treat and organisms
-Cefixime
-Ceftriaxone
-Cefaxime
-Ceftazidime
Less gram + and better gram - coverage
Also Ceftazidime covers Pseudomonas
Bacterial Meningitis
-H.Influenzae
-Pneumococci
-Meningococci
-Neisseria
PCN resistant Neisseria Gonorrhoeae
Ceftazidime - covers Pseudomonas Aeruginosa
Ceftriaxone - covers Borrelia Burdorferi - Lyme disease
what 3rd gen cephalosporin covers for Pseudomonas Aeruginosa
Ceftazidime
What 3rd gen cephalosporin covers for Borrelia Burdorferi seen in Lyme disease
Ceftriaxone
what is the 4th generation cephalosporin
Cefepime
what class is Cefepime
4th gen cephalosporin
What is 4th gen Cephalosporin (cefepime) affective against
Gram + and - and pseudomonas
-Pseudomonas aeruginosa
-Bacterial meningitis
-Nosocomial infections - does not treat MRSA
What class
Ceftaroline
5th gen cephalosporin
what is the 5th gen cephalosporin
Ceftaroline
what medications are effective against MRSA
Vancomycin
Ceftaroline
If a pt has a _____ allergy, they cannot have cephalosporins
PCN - cross reactivity
Adverse reactions for Cephalosporins
Diarrhea
Nausea
Rash
Disulfiram like reaction
-mixing with alcohol causes
-nausea
-Flushing
-rapid heartbeat
Vancomycin treats what?
is this gram + or gram -
MRSA
gram +
On the antibiotic ladder,
what is the top gun for gram + and for gram -
gram + - Linezolid (Zyvox)
gram - - Carbopenems - merapenem
Gram - coverage - lowest on abx ladder
IV and PO option
IV - Ampicillin
PO - Amoxicillin
Broad spectrum on abx ladder that covers for B lactamase bacteria …..just above Amp and amox
IV - Ampicillin/sulbactam - Unasyn
PO - Amoxicillin/Clavulanate - Augmentin
up the Antibiotic ladder on the Gram - side above Unasyn and augmentin
Covers for Pseudomonas
Broad spectrum
+ and -
and anaerobes
does not cover for MRSA or fungals
Pipercillin/Tazo (Zosyn)
-floxacin
fluoroquinolones
what routes do fluoroquinolones come in
Broad spectrum
They all come PO and IV,
Ciprofloxacin and Ofloxacin come in otic solutions
Moxifloxacin comes in ophthalmic
what are fluoroquinolones effective against
Gram negative bacteria
-Enterobacteriaceae
-Haemophilus
-Legionella
-Neisseria
-Moraxella
-Pseudomonas
Effective against certain mycobacteria
-used to treat TB
Bacterial resistance starting to see for Ciprofloxacin
fluoroquinolone base analogy on abx ladder
1st base - Ciprofloxacin
2nd base - Levofloxacin
3rd base - Moxifloxacin
1st base and 2nd base are gram neg coverage.
3rd base is both
Avoid Clarithromycin and Erythromycin in neonates due to what potential complication
Hypertrophic pyloric stenosis
Antibiotics for Community acquired pneumonia
Azithromycin PO
or
Ceftriaxone and Azithromycin IV
or
Moxifloxacin IV or PO
Antibiotics for Hospital acquired pneumonia
Vancomycin
and
Zosyn
Abx for Meningitis
Ceftriaxone
Vancomycin
+/- steroids
+/- Ampicillin - for immune compromised
ABX for UTI
Amoxicillin - pregnant
or
Nitrofurantoin - women
or
Bactrim - if no renal failure
or
Ceftriaxone - IV inpatient for pylo
or
Cipro - Outpatient for Pylo
abx for Cellulitis
Vancomycin - covers MRSA
or
Clindamycin
or
Bactrim
is e.coli gram neg or gram pos
gram neg
is PJP gram neg or pos
gram neg
Macrolides can cause what big side effect?
Long QT syndrome
azithromycin -infants
clarithromycin
Erythromycin - Everyone
PCN covers gram ___
+
Amox and Amp covers gram
+ and -
Augmentin and Unasyn cover
+ - and anaerobes
Methicillin and Oxacillin cover gram
+
Zosyn (piperacillin-tazobactam) and Timentin (Ticarcillin/Clavulanate) cover
Pseudomonas
Anaerobes
5th generation cephalosporin (Ceftaroline) covers for ____ but not _____
Covers for MRSA
Does not cover for Pseudomonas
Carbapenems cover
Gram +, -, pseudomonas, Anaerobes
*except ertapenem will not cover pseudomonas
Aztreonam covers
Gram - and pseudomonas
Quinolones cover
some gram +
gram -
Pseudomonas
Also Moxifloxacin will cover Anaerobes and Atypicals
Aminoglycosides cover
Gram -
Pseudomonas
Bactrim covers
MRSA
Gram +
Gram -
Macrolides cover
Gram +
Gram -
Atypicals
Tetracyclines (Doxycycline) cover
Gram +
Gram -
MRSA
Atypicals
Tigecycline covers
Everything except Pseudomonas
Clindamycin covers
MRSA
Gram +
Anaerobes
Vancomycin covers
MRSA
Gram +
Daptomycin covers
MRSA
Gram +
Daptomycin covers
MRSA
Gram +
Linezolid covers
MRSA
Gram +
How is CNS penetration with Cefazolin
poor
How is CNS penetration with Clindamycin
Poor
How is CNS penetration with Gentamicin
only 10-30% penetration with inflamed meninges
which drugs concentrate high in the urine
Penicillin
Cephalosporins
Aminoglycosides
Gram + or -
E. Coli
Gram -
Gram + or -
Staphylococcus
-MRSA
-MSSA
-Staph Epidermidis
Gram+
Most common organisms in CLABSI
Coagulase-negative Staphylococcus (CoNS)
S. aureus
GNR
Candida
After diagnosing a CLABSI, when would you considering removing the central line?
-Severe Sepsis
-Endocarditis
-Persistently + cultures after 72 hours of therapy
-S. aureus, GNR including Pseudomonas, Bacillus, Enterococcus
-Mycobacteria/fungi
-Tunnel site infection
-Suppurative thrombophlebitis
Gram + or -
Streptococcus
-Agalactiae (Group B Strep)
-Anginosus
- Constellatus
-Intermedius
-Pneumoniae
-Pyogenes (Group A strep)
Gram +
Gram positive cocci in clusters
Staph
Vancomycin covers
All Staph aureus including MRSA
You have a pt who you start on Vancomycin for MRSA coverage.
After your culture comes back, continue only if MRSA AND ???
What if the culture shows MSSA
CNS infection OR
Endovascular infection (ie: endocarditis)
otherwise switch to another agent like clindamycin - like for a bone infection
for MSSA
-for parenteral therapy: can use nafcillin or cefazolin
Gram + or -
Enterococcus
-Faecalis
-Faecium
Gram +
Gram + or -
Enterobacter
-Aerogenes
-Cloacae
Gram -
Drugs that offer MRSA coverage (can be limited by resistance)
-Vancomycin
-Clindamycin
-Bactrim
-Doxycycline
-Linezolid
-Ceftaroline
Gram + or -
Klebsiella
-Oxytoca
-Pneumoniae
Gram -
Gram + or -
Morganella Morganii
Gram -
In treating MRSA
What would be a smaller gun for treating MRSA rather than Vancomycin
Bactrim - In 2020 only 5% of cases were resistant
Clindamycin - 25% MRSA and 16% MSSA were resistant
Vancomycin - 100% susceptible - so best choice for initial therapy…
CoNS is frequently a blood culture contaminate but can be a real pathogen in what settings
-Preterm neonates
-CLABSI
-VP Shunt infections
-Hardware infections
-S. saprophyticus can cause UTIs in adolescents
Gram + or -
Proteus Mirabilis
Gram -
Gram + or -
Pseudomonas Aeruginosa
Gram -
Gram + or -
Salmonella species Not Typhi
Gram -
Enterococcus are inherently resistant to what drugs
Cephalosporins
Drug options for Enterococcus
Depends on susceptibility
-Ampicillin
-Zosyn
-Vancomycin
In abdominal infections:
-Carbapenems (Meropenem) will cover Ampicillin susceptible Enterococci
In VRE (Vancomycin resistant Enterococcus)
-Linezolid
-Daptomycin
Treatment for VRE (Vancomycin resistant Enterococcus)
-Linezolid
-Daptomycin
Gram + or -
Serratia Marcescens
Gram -
Gram + or -
Stenotrophomonas Maltophilia
Gram -
Cystic fibrosis isolates in Gram neg
Pseudomonas Aeruginosa (CF)
Pseudomonas Aeruginosa, Mucoid (CF)
Stenotrophomonas Maltophilia (CF)
Cystic fibrosis isolates in Gram Pos
MRSA (CF)
MSSA (CF)
treatment for Strep. pneumoniae
1st line
-PCN
-Ampicillin
-Amoxicillin (high dose so overcome resistance)
2nd line
-3rd gen cephalosporins
-Ceftriaxone and cefotaxime
-oral: Cefdinir, cefixime, Cefpodoxime
-Clindamycin
Do not use
-Azithromycin
-Bactrim
For multi-drug resistant:
-Vancomycin
-Levofloxacin
-Linezolid
Gram neg rod
pink stain
E. coli
Gram neg drugs
-Beta-Lactams
-Aminoglycosides (Gentamicin, tobramycin)
(Nephrotoxic, Ototoxic)
-Bactrim
-Fluoroquinolones (Levofloxacin, Ciprofloxacin)
(Black box warning: damage cartilage in growing children)
-Carbapenems (meropenem, imipenem)
-Others (Tigecycline, colistin)
When do you consider pseudomonas?
-Fever and neutropenia
-Ventilator Associated pneumonia
-Cystic Fibrosis
-Burns
-Chronic otitis/mastoiditis
-Osteomyelitis after nail puncture through tennis shoes
Anti-pseudomonal drugs
Beta-lactams
-Piperacillin, Ticarcillin
-Cefepime, Ceftazidime
-Carbapenems
Aminoglycosides
Fluoroquinolones
Aztreonam
When do you consider anaerobes
-Dental infections
-Deep neck infections
-Bran abscesses
-Abdominal process
Drugs with anaerobic coverage
-PCN (unless Beta lactamase positive)
-Augmentin, Bactrim
-Clindamycin
-Flagyl
-Ticarcillin-Clavulanate, Zosyn
-Meropenem/Carbapenems
What antibiotics cover osteomyelitis from S. Aureus
-Nafcillin
-Cefazolin
-Clindamycin
-Vancomycin
*4 week min
* if uncomplicated, can transition to oral therapy
What antibiotics cover osteomyelitis from Streptococci?
PCN
Ceftriaxone
*4 weeks min
What antibiotics cover osteomyelitis from Pseudomonas
Ceftazidime
Zosyn
Fluoroquinolones
-Shorter course usually okay if proper debridement
What antibiotics cover osteomyelitis from Kingella
Ceftriaxone
What antibiotics cover osteomyelitis from Salmonella
Ceftriaxone (ampicillin if susceptible)
- 4 weeks min
For Osteomyelitis what would you cover with while waiting on Culture
Vancomycin - staph
Ceftriaxone -strep, kingella, salmonella
doesn’t cover for pseudomonas
CSF analysis
OP < 20
WBC <5
Protein 15-45
Glucose 45-80
Stain/Cx Neg/Neg
Normal CSF
CSF analysis
OP elevated
WBC >1000
Protein >100
Glucose <40
Stain/Cx Pos/Pos
Bacterial
CSF analysis
OP WNL
WBC <300
Protein <150
Glucose WNL
Stain/Cx Neg/Pos
Viral
CSF analysis
OP Very elevated
WBC <500
Protein >100
Glucose <50
Stain/Cx Pos/Pos
TB
CSF analysis
OP elevated
WBC <200
Protein Elevated
Glucose WNL
Stain/Cx Neg/Neg
Abscess
meningitis etiology by age
< 1 mos
-GBS
-E.coli
-Listeria Monocytogenes
1-3 mo
-Neonatal pathogens
-S pneumoniae
-N. meningitis
-Hib
3-6 mos
-S. pneumoniae
-N. meningitis
-Hib
> 7 mo - 21 yrs
-S. pneumoniae
-N. meningitis
abx to cover meningits
usually
Vancomycin + Ceftriaxone if > 1 month
Vanc (just in case strep pneumo that is resistant to Rocephin)
Ceftriaxone (strep pnemo and N. meningitis)
Neonates - Ampicillin and Ceftazidime (or gentamicin)
Infants and children: Vancomycin and 3rd gen cephalosporin (Ceftriaxone)
Most likely pathogens causing sepsis in normal infants and children with no other factors
Treat?
S. pneumoniae,
N. meningitidis,
Group A streptococcus
Vancomycin + Rocephin
Most likely pathogens causing sepsis in normal infants and children with
Skin lesion, bone or joint focus, trauma
Treat?
S. aureus
Group A streptococcus
Vancomycin +/- Rocephin
Add Nafcillin if suspecting Staph
Most likely pathogens causing sepsis in normal infants and children with burns
Pseudomonas
Most likely pathogens causing sepsis in normal infants and children with uropathy or UTI
Treat?
Gram - enterics
-Rocephin (if differential does not include pseudomonas)
-Zosyn
Most likely pathogens causing sepsis in normal infants and children with Gastrointestinal source
Gram - enterics
Anaerobes
-Zosyn
-Ampicillin or Rocephin + Clindamycin or Flagyl + aminoglycoside
Acute community-acquired pneumonia in normal children: infectious etiologies
Treatment:
Birth to 3 wks
-GBS, GNR, CMV, Listeria, HSV, syphilis
3 wks to 3 months
-Viruses, GBS, S. pneumoniae, pertussis, C. trachomatis (2 wks – 4 mo)
3 mo to 5 yrs
-Viruses, S. pneumoniae, Hib, NT H. flu, Moraxella, S. aureus, S. pyogenes, Mycoplasma, think about TB too!
Children > 5 yrs
-Mycoplasma pneumoniae
-S. pneumonia, S. aureus, S. pyogenes
Treatment:
-Ampicillin for fully immunized infant or school aged
-Ceftriaxone if not fully immunized
-Local epidemiology with PCN resistance
-Life threatening infection
-empyema
Add Vanc or clindamycin if you are concerned about S. Aureus
Add azithromycin if concerned for atypical
Outpatient pneumonia management
Amoxicillin (high dose)
-Add azithromycin if need atypical coverage
oral cephalosporins not recommended
parenteral treatment for UTI
Rocephin
Cefotaxime
Ceftazidime
Gentamicin
Tobramycin
Piperacillin
most common organism for Purulent/fluctuant lesions (abscess, furuncle, folliculitis)
Staph aureus
Most common organism for cellulitis, erysipelas
GAS and other beta-hemolytic strep or S. Aureus
Most common organism for impetigo
S. Aureus or GAS
Abx for skin and soft tissue
Bactrim
Clindamycin
or Doxycycline
Most common organisms for acute otitis media
Treatment?
Streptococcus pneumoniae, nontypeable H. influenzae, and Moraxella catarrhalis
If > 2 years and uncomplicated/ non-toxic – could observe x 48-72 hours after risk/ benefit discussion with family
Antibiotics:
Amoxicillin (90 mg/kg/DAY divided into 2 doses)
Amoxicillin-clavulanate if recent betalactam use or if no response to amoxcillin
Most common organism for sinusitis and treatment
Haemophilus influenzae (nontypeable)
Streptococcus pneumoniae
Moraxella catarrhalis
Treatment:
Amoxicillin-clavulanate
GAS pharyngitis treatment
Penicillin x 10 days
Amoxicillin x 10 days is a reasonable alternative
Cephalosporins, clindamycin, and macrolides are alternatives for patients who are allergic to penicillin or who cannot otherwise tolerate penicillin
