Principles of ID and antimicrobial therapy II

part II

penicillin, amoxicillin, cloxacillin spectrum of activity

mainly gram positive bacteria

penicillin and amoxicillin cover oral anaerobes

Pip-Taz spectrum of activity

gram positive and gram negative

cephalosporin spectrum of activity

more gram negative coverage as you go up in the generations

macrolide spectrum of coverage

mainly gram negative bacteria and atypicals

tetracycline spectrum of coverage

gram positive, gram negative, and atypicals

carbapenam spectrum of coverage

some gram positive, gram negative, oral and gut anaerobes

vancomycin spectrum of coverage

gram positive bacteria

sulfatrim spectrum of activity

some gram positive, mostly gram negative

clindamycin spectrum of activity

oral anaerobes

linezolid spectrum of coverage

gram positive bacteria

nitrofurantoin spectrum

gram negative

metronidazole spectrum of coverage

oral and gut anaerobes

FQ coverage

gram negative bacteria

atypicals

Moxifloxacin coverage

gram negative, oral and gut anaerobes, and atypicals

which drugs have MSSA coverage

Pip/Taz or Amoxi/clav

Most cephalosporins (not ceftazidime)

Carbapenems

Levo/Moxi

Cloxacillin

MSSA & MRSA Coverage

Vancomycin

Linezolid

SMX/TMP

Clindamycin

Tetracyclines

Daptomycin

Tigecycline

Ceftrobiprole

penicillin and amoxicillin coverage of gram positives

Strep. pyogenes

E. faecalis

Amoxi/Clav gram positive coverage

Strep. pyogenes

S. aureus

E. Faecalis

Cloxacillin gram positive coverage

Strep.pyogenes

S. Aureus

Pip/Taz coverage of gram positives

Strep.pyogenes

S. aureus

E.faecalis

cephalexin gram positive coverage (1st gen)

s.pyogenes

s.aureus

same as penicillin and amoxicillin

cefuroxime (2nd gen) and ceftriaxone (3rd gen) gram positive coverage

strep.pyogenes

S.aureus (less than 1st gen)

ceftazidime gram positive coverage

none

cefepime (4th gen) gram positive coverage

s.pyogenes

s.aureus

ceftolozane/tazobactam gram positive coverage

none

which penicillin covers enterococcus

cloxacillin

Which antibiotics are unsafe in pregnancy

Safe Fetus MMeans Avoid These Now

Sulfatrim

FQ

Macrolides (Azithromycin, Clarithromycin)

Metronidazole

Aminoglycosides

Tetracyclines

Nitrofurantoin

Which trimesters should sulfatrim be avoided in

1st and 3rd

CI near term

which trimester is FQ CI in

CI in all 3 trimesters

which trimester should metronidazole be avoided in

avoid during 1st trimester (variable recommendations)

which trimesters should aminoglycosides be avoided in

all trimesters

when is nitrofurantoin C/I in pregnancy

at term and during labour

1st trimester exposure controversial

When is metronidazole safe in breastfeeding

after 6 months of age

what can be done if a mother is breastfeeding and on metronidazole

may stop breastfeeding for 12-24 hours to allow excretion of dose following a single dose of 2 g

are FQs compatible in breastfeeding

use with caution (ideally avoid)

limited human data

Sulfatrim compatibility in breastfeeding

safe in healthy term infants without G6PD deficiency

proceed with caution if nursing infant has jaundice or is ill, stressed, or premature

nitrofurantoin breastfeeding compatibility

avoid when breastfeeding infant < 1 month old and G6PD deficiency

which antibiotics do not require renal dose adjustment

azithromycin

erythromycin

cloxacillin

penicillin VK

ceftriaxone

clindamycin

doxycycline

linezolid

moxifloxacin

fidaxomicin

rifaximin

chloramphenicol

minocycline

tigecycline

what is a type I hypersensitivity reaction to beta-lactam

immediate hypersensitivity (IgE)

hives, angioedema, bronchospasm, hypotension, larygeal edema, abdominal issues

how soon after administration does a type I hypersensitivity reaction occur

symptoms start within 1 hour of ingestion of initial dose

type II hypersensitivity reaction to beta lactam

Cytotoxic (IgG/IgM)

thrombocytopenia, interstitial nephritis, hemolytic anemia

how soon does Type II hypersensitivity reaction occur

within 72 hours, up to weeks

Type III hypersensitivity reaction to beta lactams

immune complex formation (complement)

serum sickness syndrome

how soon does a type III reaction occur

within 1-3 weeks

type IV hypersensitivity reaction

contact dermatitis, maculopapular eruptions, SJS/TEN, DRESS

how soon after taking a beta lactam can a type IV reaction occur

symptoms start after days of treatment

Macrolides in pregnancy

azithromycin and erythromycin considered safe

clarithromycin avoid if possible

generally avoided if possible

which drugs have activity against VRE (vancomycin resistant enterococcus)