Exam 3 - RTIs Flashcards
Main physiologic mechanisms that prevent lung infections?
Upper Airways: Nasopharynx, Oropharynx
Conducting Airways: Trachea, Bronchi
Lower Respiratory Tract: Terminal airways/alveoli
Host defense mechanisms seen in the nasopharynx?
nasal hair turbinates anatomy of upper airways mucociliary apparatus IgA secretion
Host defense mechanisms seen in the oropharynx?
saliva
sloughing of epithelial cells
complement production
Host defense mechanisms seen in the trachea/bronchi?
cough epiglottis reflexes sharp/angled branching airways mucuociliary apparatus Immunoglobulin production (IgG, IgM, IgA)
Host defense mechanisms seen in the terminal airways/alveoli
alveolar lining fluid (surfactant/fibronectin, complement, immunoglobulin) cytokines (TNF, IL-1, IL-8) Alveolar macrophages PMNs Cell mediated immunity
Host defenses:
_______ inhibits adherence of bacteria to cell surfaces –> prevents colonization
fibronectin
Host defenses:
Microbes possess surface adhesions, pilis, exotoxins, and proteolytic enzymes that degrade _____ –> promote colonization
IgA
Host defenses:
Adherence of microorganisms to _______________ = critical first step in colonization and subsequent infections
epithelial surfaces of upper airways
Host defenses:
_______ secretions contain non-specific inhibitors of infection
respiratory
Host defenses:
________ eliminate organisms by phagocytosis and produce cytokines that recruit neutrophils to the lungs –> local area becomes ______ and _____ = impairs phagocytic activity
alveolar macrophages
acidic/hypoxic
Factors that will interfere with host defenses:
what 7 things are known to do this…?
Altered level of consciousness Smoking viruses Alcohol Endotracheal tubes/NG tubes, Ventilators Immunosuppression Elderly
why does altered level of consciousness lead to decrease host defenses?
altered level of consciousness –> compromise epiglottic closure –> aspiration
why does alcohol alter/lead to a decrease in host defenses?
- impair cough/epiglottic reflexes –> aspiration
- increases oropharyngeal colonization w/ gram NEGATIVE organisms
- decreased mobilization of neutrophils
what are examples of immunosuppression that can lead to decrease in host defenses
malnutrition
immunosuppresive therapy…
HIV
what does CAP stand for?
community acquired pneumonia
what does VAP stand for?
ventilator associated pneumonia
what does HAP stand for?
hospital acquired pneumonia
what does HCAP stand for?
healthcare associated pneumonia
what is the most common cause for BACTERIAL pneumonia
Aspiration
what is aspiration?
common thing to happen in people during sleep
means you’re breathing foreign objects into your airways. Usually, it’s food, saliva, or stomach contents when you swallow, vomit, or experience heartburn
what is aerosolization
droplet nuclei (breathing in viruses)
most common way that VIRUSES are caught for pneumonia?
aerosolization
most common bugs seen in CAP
STREPTOCOCCOUS PNEUMONIAE!! H. Influenzae Mycoplasma Pneumoniae Legionella pneumophila Chlamydophila pneumoniae Staphylococcus aureus Viral!!!!!
what is the MOST common cause of CAP
VIRUSES!!
what is the most common bug that causes bacteremic pneumonia cases
streptococcus pneumoniae
what are risk factors for drug resistant s. pneumoniae (DRSP)
extremes of age (< 6; > 65)
PRIOR ABX THERAPY
underlying illnesses, co morbid conditions
day care attendance (infested kids
recent/current hospitalization
immunocompromised/HIV/nursing home/prison
Typical or atypical pathogen?
Mycoplasma pneumoniae
atypical
NO CELL WALL = NO GRAM STAIN
Typical or atypical pathogen?
Legionella pneumophila
atypical
Typical or atypical pathogen?
Chlamydophila pneumoniae
atypical
Typical or atypical pathogen?
staphylcoccus aures
typical
Typical or atypical pathogen?
streptococcus pneumoniae
typical
A patient may have pneumonia about 2 - 14 days after ________
seen commonly in what bugs?
after influenza
seen in staph. aures
what bug is known to be seen post influenza?
staph aureus
the following indicate a high index suspicion of what bug?
- necrotizing pneumonia or cavity infiltrates
- concurrent or recent influenza infection
- ICU admission/respiratory failure
- rapid progression of sxs
- formation of empyema
high suspicion of MRSA
also if pt has hx of skin infection with CA-MRSA….
_________ should be performed on all outpatients and inpatients with suspected CAP
chest radiography
Sputum Exam:
Rust colored = what bug?
Dark red, mucoid sputum = what bug?
Foul-Smelling Sputum = what bug?
rust: s. pneumoniae
dark red: k. pneumoniae
foul: mixed anaerobic infection
what score is used to evaluate severity of illness and predict mortality (in RTI lecture)
CURB 65
what is CURB65
score used to evaluate severity of illness and predict mortality C: "C"onfusion U: "U"remia R: "R"espiratory rate B: low "B"lood pressure > "65" y.o
CURB65:
if score of ____: treat as outpatient
if score of ____: admit to general ward
if score of ____: may require ICU care
0 - 1
2
>/= 3
EMPIRIC CAP Outpatient Treatment:
what patient factors matter when picking this treatment?
if pt is healthy or not (comorbid conditions?)
any prior abx use in past 3 months?
drug allergies of course
if region has a high resistant rate
EMPIRIC CAP Outpatient Treatment:
If pt is healthy and has no prior antibiotic use within previous 3 months — treat with that?
Macrolide (erythromycin, clarithromycin, azithromycin)
or
Doxycycline
*remember drug interactions for drugs above)
EMPIRIC CAP Outpatient Treatment:
If pt has comorbidities OR has used antimicrobials in past 3 months — treat with what?
(comorbidities could be chronic heart/liver/lung/renal disease, diabetes, alcoholism, malinancy or asplenia)
Respiratory FQ (Moxifloxacin or Levofloxacin)
OR
Beta-Lactam + Macrolide
EMPIRIC CAP Outpatient Treatment:
if in region with a high rate (>25%) of infections caused by high level (MIC > 16) MACROLIDE resistant S. Pneumoniae — treat with what?
Respiratory FQ
OR
Beta Lactam + Macrolide
EMPIRIC CAP Inpatient Treatment:
If patient is in general medical ward (non-ICU) — how to treat?
Respiratory FQ
OR
Beta lactam + macrolide
(Use IV!!)
EMPIRIC CAP Inpatient Treatment:
If patient is in ICU — how to treat?
DUAL THERAPY
Beta lactam + Macrolide
OR
Beta lactam + Respiratory FQ
what are the preferred beta lactams for empiric CAP inpatient treatment
Ceftriaxone
cefotaxime
ampicillin
CAP Directed Therapy:
If Strep. Pneumo:
Based on its resistance mechanism:
get results that let you know if it is ______ or _____
PCN susceptible (MIC <2) or PCN resistant (MIC > 2)
CAP Directed Therapy:
If Strep. Pneumo and PCN susceptible – treat with what?
PCN G or amoxicillin
*if deathly allergic ot PCN — macrolide, cephalosporin, Respiratory FQs or doxy….
CAP Directed Therapy:
If Strep. Pneumo and PCN resistant – treat with what?
respiratory FQ or ceftriaxone or cefotaxime
Specific Conditions and Specific Pathogens for CAP:
If on hotel/cruise ship in previous 2 weeks – worried about what bug?
Legionella pneumophila
Specific Conditions and Specific Pathogens for CAP:
If IV drug user – worried about what bug?
S. Aureus (skin flora)
Specific Conditions and Specific Pathogens for CAP:
If lung abscess – worried about what bug?
CA-MRSA
what are examples of some antipneumococcal and antipseudomonal beta lactams (aka drugs good when pseudomnas suspected in pneumonia)
pip/tazo
cefepime
Carabapenems (except ertapenem bc no pseudomonas coverage!)
how long to treat CAP (minimum amount of days?)
5 days
what are signs of CAP associated clinical stability
temperature < 37.8 C (100.04..) HR < 100 BPM RR < 24 breaths PM Systolic BP > 90 Arterial O2 > 90 Ability to take oral meds normal status
Duration of CAP treatment should be at least 5 days..
also patients need to be afebrile for at least _______ and not more than _____ CAP-associated signs of clinical instability
at least 24 - 48 hours
no more than 1 CAP instability sign
Pathogen Directed Therapy for CAP: What drug for
If H. influenzae - NON beta lactamase producing?
Amoxicilin
Pathogen Directed Therapy for CAP: What drug for
If H. influenzae - beta lactamase producing?
2nd/3rd gen ceph
or
Amox clav
Pathogen Directed Therapy for CAP: What drug for
Mycoplasma or Chlamydophila?
macrolide or doxycycline
Pathogen Directed Therapy for CAP: What drug for
Legionella
FQs
Azithromycin
Pathogen Directed Therapy for CAP: What drug for
Staph Aureus:
MSSA?
MRSA?
MSSA: nafcillin or oxacillin
MRSA: Vanc or linezolid
Pathogen Directed Therapy for CAP: What drug for
Anaerobes?
beta lactam + beta lactamase inhibitor
or
clindamycin
Pathogen Directed Therapy for CAP: What drug for
Enterbacteriaceae (if KPC/AmpC producing..)
3rd/4th ceph
or
Carbapenem
