Lower Respiratory Infections Flashcards
Most common infections involving lower respiratory tract?
bronchitis, bronchiolitis, pna
What is bronchitis?
inflammation of the walls of the bronchi and bronchioles which causes narrowing
What is bronchiesctasis?
widening of the bronchi and bronchioles but excessive mucus production narrows the bronchial tree
Acute bronchitis usually affects who? chronic bronchitis? bronchiolitis?
ind. of all ages
adults
infancy
Signs/sxs of bronchiolitis?
Prodrome with irritability, restlessness, and mild fever
Cough and coryza, V/D, noisy breathing, and increased RR
Labored breathing with retractions, nasal flaring, and grunting
tachycardia, wheezing/inspiratory rales
Main cause of Acute bronchitis?
mostly viral, so no abx
therapy is symptomatic: Ibuprofen/Acetaminophen, fluids for rehydration
antitussives rarely indicated
What bacteria can cause bacterial acute bronchitis?
mycoplasma pneumoniae
Chlamydophilia pneumoniae, B. pertussis
When should you suspect bacterial etiology of acute bronchitis?
fever for more than 4-6 d
predisposed pts (immunocompromised)
if suspected by hx of if confirmed by culture serology/PCR
How can you tx bacterial acute bronchitis?
azithromycin or respiratory fluoroquinolone
Acute bronchiolotitis
RSV is the most common cause
usually self limiting in healthy infants
if severe: +/- O2 therapy, IV fluids, subset (aerosolized bronchodilators, Ribavirin)
What pts can benefit from Ribavirin?
pts with bronchopulmonary dysplasia, congenital heart disease, prematurity or immunodeficiency
other tx approach for acute bronchitis in pts with underlying pulmonary or cardiovascular disease?
Prophylaxis against RSV
- give monthly during RSV season
- RSV immune globulin or Palivizumab ( a monoclonal ab for RSV)
ADEs of Palivizumab?
fever, rash, ab formation, anaphylaxis (rare), thrombocytopenia
Hallmark of chronic bronchitis?
chronic cough, excessive sputum production, expectoration w/ persistent presence of microorganisms in the pts sputum
signs/sxs of chronic bronchitis?
excessive sputum expectoration, cyanosis
PE: in/exp rales, rhonchi and mild wheezing. Hyperresonance on percussion.
Tx for chronic bronchitis?
attempts to mobilize and enhance sputum expectoration: chest physiotherapy, humidification of inspired air
O2
aerosolized bronchodilators (albuterol)
abx
Most common organisms that cause chronic bronchitis?
H. Influenzae, M. Catarrhalis, S. pneumoniae, E. coli
What abx should you use for the tx of chronic bronchitis?
which ever abx has the lowest resistance and highest sensitivity
signs/sxs of pna?
abrupt onset of fevers, chills, dyspnea, productive cough
rust colored sputum or hemoptysis
pleuritis CP
Pna PE?
tachypnea and tachycardia. Dullness to percussion, increased tactile fremitus, CW retractions, diminished breath sounds over affected areas, inspiratory crackles during lung expansion
Pna CXR? lab tests?
dense lobar or segmental infiltrate
leukocytosis w/ predominance of polymorphonuclear cells
low O2 sat
Most common cause of CAP in adults?
S. pneumoniae
other causes: m. pneumoniae, legionella species, C. pneumonia, H. influenzae
Tx for CAP?
humidified oxygen for hypoxemia
bronchodilators when bronchospasm present
fluids
chest physiotherapy
abx (based on presumed causative pathogens)
Recommended empiric abx for healthy pts with CAP, no abx in last 3 months?
Macrolide or Doxycycline
Recommended empiric abx for CAP pt with comorbid conditions?
respiratory fluoroquinolone
or macrolide + beta lactam
Recommended empiric abx for pts living in regions with high rates of macrolide resistant to S. pneumoniae?
respiratory fluoroquinolone
or macrolide + beta lactam
Inpt therapy for CAP, for pt not in ICU?
respiratory fluoroquinolone
or macrolide + beta lactam ( for fluoroquinolone allergy)
CAP tx for pts admitted to ICU?
Azithromycin or respiratory fluoroquinolone + anti-pneumococcal beta lactam
PCN all: fluoroquinolone + Aztreonam
Tx of CAP for pts at risk for pseudomonas infection ?
antipneumococcal, antipseudomonal beta lactam
+ aminoglycoside (gentamicin, tobramicin)
+Azithromycin or respiratory fluoroquinolone
Tx for CAP in pts at risk for MRSA
antipneumococcal, antipseudomonal beta lactam
+ aminoglycoside (gentamicin, tobramicin)
+Azithromycin or respiratory fluoroquinolone
+ Vancomycin or Linezolid
???
Risk factors for multi drug resistant pathogens (MDR)?
abx therapy within the last 3 mos, septic shock, ARDS, 5+ days in hospital prior to HAP/VAP, acute renal replacement, tx in a unit where local susceptibility rates are not known
Risk factors for MRSA in pts with HAP and VAP?
abx therapy in the last 3 mos, renal replacement therapy, use of gastric acid suppressive agents,+ culture or MRSA in the past 3 mos, hospitalized in unit where prevalence of MRSA is not known
Risk factors for pseudomonas aeruginosa and other gram - bacilli?
abx therapy in the last 90 days
structural lung disease
recent hospitalizations
+ culture within the past yr
Recommended initial empiric abx for HAP and VAP?
one of the following:
Piperacillin-tazobactam (Zosin)
Cefepime
Levofloxacin
Imipenem
Meropenem
Recommended initial empiric tx for HAP/VAP in pts with risk factors for MRSA?
Pick one: Piperacillin-tazobactam (Zosin), Cefepime, Ceftazidime, Levofloxin, Aztreonam, etc.
+ one:
Vancomycin or Linezolid
Recommended initial empiric abx tx for HAP with risk factors for pseudomonas?
Pick one: Piperacillin-tazobactam (Zosin), Cefepime, Ceftazidime, Levofloxin, Aztreonam, etc.
+ one:
Levofloxacin, Gentamicin, Tobramycin, Aztreonam
Recommended initial empiric abx for HAP/VAP with risk factors for MRSA, MDR, pseudomonas and other gram - bacilli?
Pick one: Piperacillin-tazobactam (Zosin), Cefepime, Ceftazidime, Levofloxin, Aztreonam, etc.
+ one:
Levofloxacin, Gentamicin, Tobramycin, Ciprofloxacin
+one:
Vancomycin or Linezolid
which organisms cause pna in peds?
RSV, parainfluenza, adenovirus
M. pneumoniae in older children
Name a first generation cephalosporin. Use?
Cephalexin
skin, soft tissue, UTIs
Name a second generation cephalosporin. Use?
Cefotetan
Cefoxitin
Cefuroxime
more active v. S pneumoniae and H influenzae, B fragilis
Name a third generation cephalosporin. Use?
Ceftriazone
Cefixime
Cefotaxine
Ceftazidime
many uses including pna, meningitis and gonorrhea. Broad activity, beta lactamase stable
Name a 4th generation cephalosporin. Use?
cefipime
pseudomonas coverage
Name a 5th generation cephalosporin. Use?
ceftaroline
skin, CAP
PK of cephalosporins
oral use for older drugs, mostly IV for newer drugs
renal elimination, short half lives
third gen. drugs enter CNS
ADEs of cephalosporins
hypersensitivity rxn
first gen. partial cross reactivity with penicillins
GI upset
Name a carbapenem. Use?
Imipenem-cilastatin (a beta lactam)
broad spectrum, some PRSP strains, gram negative rods, pseudomonas sp
