Lecture 15: Respiratory Tract Infections Flashcards
What are some of the Host Defense Mechanisms?
- Nasopharynx [Nose hair, mucociliary apparatus, IgA]
- Oropharynx [Saliva, Epithelial Cells]
- Trachea, Bronchi [Cough, epiglottic reflexes]
- Terminal Airways, Alveoli [Surfactant]
What are some important things to know about the Host defenses?
- IgA promotes colonization
- Alveolar Macrophages: increase acidity in lungs = hypoxic
What are some factors that interfere with host defenses?
- Altered Consciousness
- Smoking [disrupts mucociliary]
- Viruses [S. Aureus]
- Alcohol
- Mechanical Vent
- Asplenia [S. Pneumoniae]
- Elderly
What is Community-Acquired Pneumonia?
- Pneumonia developing OUTSIDE the hospital or < 48 hours. after admission
- CAP
What is the pathogenesis of CAP?
- Aspirations [Bacterial]
- Aerosolization [droplets]
- Bloodborne [Mostly becomes this]
Basically what you are breathing in
What are the specific pathogens that are found in CAP?
- Streptococcus Pneumoniae
- Haemophilus Influenzae
- Myocplasma Pneumoniae
- Legionella Pnenmophila
- Chlamydia Pneumoniae
Not really S. Aureus; only if there is a history of it
When discussing Streptococcus Pneumoniae in CAP, what are some of the drug resistant risl factors?
- Antibiotics within 3 months
- Age > 65
- DM, CAD, CHF, HIV
- Alcohol Abuse, Cirrhosis
- Immunosrppressive Medications
When discussing Mycoplasma Pneumoniae, what is important to know?
- Atypical Pathogen; spreads person-to-person
- Presents with Cough, Ear Pain, Nausea, Vomiting, Diarrhea
- NO consolidation
When discussing Legionella Pneumophila, what is important to know about it?
- Atypical Pathogen
- Transmitted by inhalation of areosols
- More so affects: Male, middle age, smokers
When discussing Staphylococcus Aureus, what is important to know about it?
- Post Influenza [worsened illness suddenly]
- If nares are MRSA (-) by PCR; then most like dont have it [98.1% right]
What is the clinical presentation of CAP?
- Sudden onset of fever, chills, chest pain, SOB, prodcutive cough
- Tachycardia, Blood Pressure [Increased 10 bpm for every oC elevation
What are some of the important pysical exams for CAP?
- Tachypnea, Cyanosis, Nasal Flare = Serious Respiratory Compromise
- Conslidation [Dullness, Crackles, Egophany (E->A sounds)]
What are some of the important Radiography that should be done for CAP?
- ALL patients should get
- Dense Lobar Conslidation
What is the Major Criteria for Severe CAP?
- Respiratory Failure
- Septic Shock [needing Pressors]
NEEDS ONE
What is the Minor Criteria for
Severe CAP?
- RR > 30 bpm
- Hypotension
- Multilobar
- Confusion
- Uremia [BUN >20]
- Leukopenia
- Thrombocytopenia
- Hypothermia
NEEDS >2
What are the two important clinical predictions for the Prognosis of CAP?
- Pneumonia Severity Index [PSI]
- CURB-65 [Confusion, Uriema, Respiratory Rate, Low Blood Pressure, Age > 65]
What is the Empiric Treatment of CAP for Healthy outpatients WITHOUT comorbidites?
- Amoxicillin 1g po q8h
- Doxycycline 100mg po q12h
- Azithromycin 500mg PO, then 250mg PO
- Clarithromycin 500mg PO q12h
Macrolide ONLY used when the resistance is < 25%, most likely not going to use them
What is the Empiric Treatment of CAP for outpatients WITH comorbidites?
- Levi 750mg qd or Moxi 400mg qd
- B-lactam + Mac OR B-lactam + doxycycline
- Augmentin, Cefodoxime, Cefuroxime
- Azithromycin; Clarithromycin 500mg
- Doxycycline 100mg q12h
FQ: QTc prolongation, drug-drug interactions [cations/warfarin], renal impairment [levo]
What is the Empiric Treatment of Non-severe CAP inpatient?
- B-lactam + Mac [Unasyn, Cefotaxime Ceftraixone, Ceftaroline + Azitromycin, Clarithromycin]
- Levo 750mg or Moxi 400mg
- B-lactam + Doxycycline [if contrainidated to FQ & MACs]
What is the Empiric Treamtent of Severe CAP inpatient?
- B-lactam + Mac [Unasyn, Cefotaxime, Ceftriaxone, Ceftaroline + Azithromycin, Clarithromycin]
- B-lactam + FQ [Unasyn, Cefotaxime, Ceftriaxone, Ceftaroline + Levo, Moxi]
FQ maybe not used as much because of the increasing resistance to them
With the Empiric Treatmets of CAP, what should be used in the Concern of MRSA or Pseudomonas Aeruginousa?
- MRSA: NASAL PCR 1st; + Vancomycin or linezolid
- P.Aeruginosa: Zosyn, Cefepime, Ceftazidime, Aztreonam, Meropenem, Imipenem
NO Dapto for MRSA
NO Erta for P. Aeruginosa
When should Corticosteroids be used in the treatment of CAP inpatient?
- Not really used in nonsevere or severe
- Might be good in refractory septic shock?
MACs have an inflammtory repsonse, so maybe corticosteroids may be good?`