Sweatman Bacterial Infections of the Lungs Flashcards
what constitutes lower respiratory region
respiratory bronchioles, alveolar ducts, alveoli
symptoms of pneumonia
fever cough with our without sputum dyspnea chest pain infiltrates on radiograph (diagnostic)
unproducitve cough=
viral or mycoplasma
most important factor is successful tx. of pneumonia
early intervention (mortality decreases when you wait even 8 hours)
4 types of pneumonia
CAP
nocosomial
aspiration
immunocompromosed host
define nocosomial/hospital acquired
appears within 48 hours of arrival/admission without evidence of existing prior to arrival
most common agent 0-6 weeks for CAP
group B strep
E coli
most common agents 6 weeks-18 yrs for CAP
viruses (flu, RSV, rino, parflu, adeno)
Myco pneumonia
chlamydia pneumonia
Strep pneumonia
most common 18-40 yrs for CAP
Mycoplasma pneumonia
strep pneumonia
most common 40-65 cor CAP
Strep pneumonia H flu anaerobes (bacteroides, fusobacterium) viruses mycoplasma pneumonia
most common >65 yrs for CAP
Strep pneumonia Viruses Anaerobes H flu Gram +ve rods
most common causes of nococosmial pneumonia
S. aureus,
P aeruginosa
Most common cause of Pneumonia in Dm and Alcoholic pt.’s
Klibsielle Pneumonia
currant-jelly sputum
Pt.’s with Dm should get
annual Flu vaccine and pneumococcal pneumonia–> DM inhibits the protective proteins in airways…very susceptible to Flue and its effects….worse immune system as well
is there vaccines againts staph
no
is there vaccines against pneumococcal pneumonia
yes–> strep. pneumonia
transplant pt.’s are also susceptible to
CMV infection
gram negative aerobe that thrives in water environment
legionella pneumophilia
–> atypical causative agent for pneumonia
name the respiratory quinolones
levofloxacin
cipro
moxifloxacin
*acheive good levels in lung tissues
commonly employed for legionella
azithromycin, clarithromycin
method for tx of penumonia
catergorize based on demographics
treat with broad spectrum pending labs
(take into account individual pt., resistance, local microbe info)
Outpatient no other modifying factors
Macrolide of doxycycline
Outpaitient with COPD, no steroids of Antibiotics in 3 months
2 gen macrolide
(clarithromycin) or doxycyline
Outpaitient, COPD, steroids or antibiotics in three months
floraqunolone, or augmentin, or clarithromycin (2nd gen.) +/- cephalosporin
Nursing home
floraqunolone, or augmentin, or clarithromycin (2nd gen.) +/- cephalosporin
Hospital Ward
floraqunolone, or augmentin, or clarithromycin (2nd gen.) or azithromycin (3rd gen.) +/- cephalosporin
ICU first option
3rd gen cephalosporin+/- macrolide or piperacillin (broad)/tazobactam or floroquinilone
zosyn
piperacillin/tazobactam (beta lactamase inhibitor)
ICU with risk of P aeruginosa
antipsuedomonal florquinolone (cipro) + beta actam or
macrolide + 2 antipseudomonal agents
why adjust for recent seroid use
pt. assumed to have realignment of local flora
MOA for macrolides
50s ribo blocker–>prevent translation
MOA for tetracyclines (doxycycline)
30s ribosomal blocker–> inhibts protein synthesis
MOA for floroquinolones
DNA gyrase inhibitor–> prevents DA repication
Penicillin MOA
block cell wall cross linkage
MOA for carbapenem
blocks cell wall cross-linkage
MOA for cephalosporins
inhibit cell-call cross-linkage
3rd gen cephalosporin with anti-pseudomonal activity
cefepime
MOA for aminoglycosides (gentamicin)
30s ribosomal inhibitor
resistance mech. for macrolides
mutation of 23s rRNA, ribosomal methylation, active efflux
tetracyclines restance mech.
decreased entry/increased efflux, target insensitivity
resistance mech to floroqiunolones
mutation of DNA gyrase, active efflux
resistance mech. to cephalosporins
dereased permeability of gram negative outer membrane (altered porins), ective efflux
resistance mech for aminoglycosides
drug inativation (aminoglycoside modfying enzyme)
dec perm of gram negative outer membrane
active efflux
ribosomal methylation
most common nocosomial organism
Staph aureus, p aeruginosa
drugs indicated in NOCOSOMIAL pneumonia
- imipenem/ cilastin–> meropenem
- axtreonam–> zosyn
- ceftazidime–> cefepime
- vancomysin (IV)
carbapenem with less side effects
meropenem
drug reserved for cetazidime resistant
cefepime-> 4th gen and anti-pseudomnal
50% of isolate for pt.’s with aspiration pneumonia are…
gram negative bacteria
- 16% anaerobes
- 12% staph aureus
risks factors for aspiration pneumonia
Unconsiousness–> loss of protective reflexes
long term intubation
foreign body
gastric acid
semi-recumbant positioon and unable to expectorate material in airway
indicated in aspiration pneumonia
clindamycin–> ampicillin/sulbactam
tx for aspiration pneumonia must include protection against
anerobes such as H. flu
MOA for clindamycin
50s ribosomal inhibitor blocking translocation
resistance mech for clindamycin
meythlation of binding site, enzymatic inactivation
Vancomycin MOA
Bind D-ala-D-ala terminus of peptide precursor units, ihibiting peptidoglycan polymerase and transpeptidase reaction (cell wall proliferation inhibitor)
resistance to VANC
replacement of D-ala by D-lactate
Vancomycin only works on
gram positive bacteria
dosing route consideration for Ab’s
oral for mild infections (no Gi problems, adherent, other chelating drugs)–> parenteral is severe–> may swithc to oral when controlled
Ab’s with highest oral bioavailability
Florquinolones and doxycycline
three major relationships to consider when choosing a medication for pneumonia
- AUC/MIC
- Cmax/MIC
- T>MIC
dosing parameters for concentration dependent drugs
large doses relative to MIC at long intervals relative to serum half life
example of concentration dependent drugs and their dosing
once daily aminoglycosides
2g of have with pt.s in normal renal function
time dependent dosing parameters
dosed more frequently, with emphasis on the need to maintain serum drug level above MIC for 30-50% of dose interval
example of time dependent meds
constant infusion of beta lactams to ensure maximal T>MIC
T>MIC greatest consideration for
penicillins, cephalosporins, carbapenems
24 hour AUC/MIC greatest consideration for
aminiglycosides, floroquinolones, tetracylines, vancomycin, macrolides, clindamycin
cMAX/MIC greatest consideration for
aminiglycosides. floroquinolones
which drugs DO NOT REQUIRE DOSE ADJUSTMENT FOR RENAL IMPAIRMENT
(entirely billiary or renal/billiary)
azithromycin, ceftriazone, clindamycin, dxy, erythromycin, linezolid
(all others do require adjustment)
drug with renal metabolism not just exceretion
imipenem
ab’s metabolized by liver cyp’s
linezolid
Major toxicity for amoxicillin
cross reactive with penicillin sensitivity,
ampicillin toxicity
maculopapular rash
azithromycin toxicity
QT prolong, chelestatic jaundice
cefazolin cross-reactivity
complete cross reactivity within cephalosporins, penicillin cross-reactivity
doxycylcine toxicity
teeth discoloration, dec bone growth, photosensitivity
erythromycin toxicity
cyp 3A4/pgp inhibitor, QT prolong, cholestatic jaundice
gentamicin toxicity
nephro and ototoxicity, neuromuscular paralysis
imipenen toxicity
cross-reactive with penicillin, cephalosporin toxicity
levofloxacin toxicity
tendon rupture in adults, cartilage damage in young children
linezolid toxicity
non-specific MAO inhibitor
meropenem toxicity
cross-reactive with pen/ceph
piperacillin toxicity
cross reactive with ceph, decreases coagulation (bleeding tendencies)
vancomycin toxicity
neophro and ototoxicity, Red Man’s syndrome
cross reactivity related to…
presence of beta lactam ring that is rpesent in multiple drug classes
augmentin
amoxicillin/clavulonate
zosyn
pieracillin/tazobactam
unasyn
ampicillin/sulbactam
benefit of conjugating with a bactam/clavulonic
increases the duration of the effect of the beta lactam antibiotic by irreversibly inhibito the beta-lactamases
primaxin
imipenem/cilastin
Cilastin MOA
Reversible, competitive inhibitor of renal DHP-1, an enzyme which breaks down imipenem to inactive but nephrotoxic metabolites
antibiotic not used for pulmonary infections
daptomycin (cubicin)
why is daptinomycin not used for pneumonia
though it distributes to lung tissues…this drug is inhibited by pulmonary surfactant
Bronchitis in young people
viral
Bronchitis in elderly patients with other comorbitities
bacterial
common bugs that cause acute bronchitis in the elderly
Mycoplasma pneumonia, strep pneumonia, H flu, Moraxella catarrhalis and Bordatella pertusis
most common cause of acute bronchitis in smokers
H. influenza
indicated drugs in acute bronchits
- augmentin–> ciprofloxacin if resistance
- azithromycin
- clarithromycin
- doxycycline
Lung Abcesses most likley cuased by
Anaerobes
+ gram negative cocci
+ gram positive bacilli
nocosomial lung abcesses
gram negative bacilli
community acquired lung abcesses
gram positive cocci
treatment for lung abcesses
- clinda mycin (better than penicillin vs. bacteroides)
2. metronidazole + ceftriaxone (for nocosomial infections)
gram negative lung abcesses
metronidazole + ceftriaxone
gram positive cocci lung abcesses
clindamycin
List the tx for CAP in order of preference
Macrolide or respiratory quinilone
or
amoxicillin/clavulonate
treatment for abcess and aspiration pneumonia should cover for
anaerobes
