LRTI Flashcards
Host Defense Mechanisms
Nasopharynx (5)
- nasal hair
- anatomy of upper airways
- IgA secretion
- mucociliary apparatus
- fibronectin
Host Defense Mechanisms
Trachea/Bronchi (5)
- cough
- epiglottic reflex
- anatomy of conducting airways
- mucociliary apparatus
- immunoglobulin
Host Defense Mechanisms
Oropharynx (3)
- saliva
- slough epithelial cells
- complement production
Host Defense Mechanisms
Alveoli/Terminal Airways (4)
- alveolar lining fluid
- cytokines
- macrophages + PMNs
- cell-mediated immunity
What happens when the body doesn’t do its job?
Host interventions
- ___ and ___
- altered level of consciousness
- endotracheal tubes
Host Disease States
- immunosuppression
- ___
- asplenia
- ___
- smoking, alcohol
- dibetes mellitus
- elderly
What happens when the body doesn’t do its job?
Pathogen Mediated
- surface ___
- pili
- ___
- enzymes
Defenses Gone Wrong
- alveolar macrophages
- phagocytosis + cytokine release → recruit neutrophils → acidic and hypoxic environment → ___ phagocytosis
- adhesions
- exotoxins
- reduced
CAP - pneumonia that developed outside the hospital or within the first ___ hours of admission
- most ___ cause of infection related to hospitalization and mortality
- 10% hospitalized
48
common
Pathogenesis - Aspiration
- most common for ___ pnemonia
- common during ___
- organisms usually clearned if host defenses functioning properly
- disorders that impair consciousness and depress gag reflex result in increased inoculum
- bacterial
- sleep
Pathogenesis - Aerosolization
- direct ___ of pathogen
- primaryily ___ , TB, and endemic fungi
- ___ nuclei = particles containing pathogen
- inhalation
- viruses
- droplet
Pathogenesis - Bloodborne
- translocate to ___ site
- extremely unlikely
- pulmonary
Which microorganism class is the most common pathogenic organism for CAP?
a) fungus
b) bacteria
c) virus
d) protozoa
virus
Common Bacterial Pathogens
- S. pneumoniae
- H. influenzae
- atypical pathogens: ___ , ___ , and ___
- S. aureus
- Mycoplasma pneumoniae
- Legionella pneumophilia
- Chlamydia Pneumoniae
Streptococcus pneumoniae
increased prevalence and severity in pts with the following:
- asplenia
- DM
- immunocompromised
- HIV
- chronic cardiopulmonary/renal disease
Risk factors for drug resistance
- age < __ or > ___ yo
- prior Abx therapy
- co-morbid conditions
- day care
- recent hospitalization
- close quarters
PCN and Macrolide use
- ___ resistance - 3%
- ___ resistance - 45-50%
- 6, 65
- PCN
- macrolide
Mycoplasma pneumoniae
- ___ pneumonia
- ___ bacteria
- spread by person-person contact (increased risk in close contact populations)
- 2-3 week incubation period, ___ onset of symptoms
- persistent, non-productive coughm fever, headache, sore throat, rhinorrhea, N/V, arthralgia
- imaging usually more pronounced with patchy, interstitial infiltrates
- walking
- atypical
- slow
Legionella pneumophila
- ___ pathogen - found in water and soil
- spread by ___
- increased risk: older ___ , chronic bronchitis, smokers, and immunocompromised
- characteristics: multisystem involvement (high ___ , relative ___ , multi-lobar involvement, mental status change, and increased LFTs + SCr)
- atypical
- aerosolization
- males
- fevers, bradycardia,
S. aureus
___ prevalence in CAP
important to get ___ ___ ___
- 95-99% negative predictive value for MRSA in CAP
Risk factors for MRSA
- 2-14 days post ___
- previous MRSA infection/isolation
- previous hospitalization
- previous use of ___ antibiotics
- low
- MRSA nasal PCR
- flu
- IV
Risk Factors for Certain Pathogens
S. pneumoniae, anaerobes, K. pnemoniae
Alcoholism
Risk Factors for Certain Pathogens
S. pneumoniae, H. influenzae, Moraxella cattarhalis, Legionella spp.
COPD/smoker
Risk Factors for Certain Pathogens
S. pneumonia, S. aureus, H. influenzae
post influenza pneumonia
Risk Factors for Certain Pathogens
P. aeruginosa, S. aureus
(2)
- structural lung disease (cystic fibrosis, bronchiectasis)
- recent Abx exposure
Clinical Presentation
- sudden onset of fever, chills, pleurtitic chest pain, dyspnea, productive cough
- ___ onset with ___ severity for mycoplasma and Clamydia pneumoniae
Elderly Pts
- classic symptoms may be ___ (afebrile, mild leukocytosis)
- more likely to have decrease in ___ status, weakness, and ___ status changes
Vitals: febrile, ___ cardia, ___ tensive, tachypnea
- gradual, lower
- absent
- functional, mental
- tachycardia, hypotensiver
Clinical Presentation
Chest X-ray
- recommended for all patients with suspicion for CAP
- dense lobar consolidation/infiltrates = ___ origin
- patchy, diffuse intersitital infiltrates = ___ or ____ pathogens
Sputum Characteristics
- color, amount, consistency, and odor observed
Gram stain
- only evaluate samples with > ___ PMNs and < ___ epithelial cells
- S. pneumoniae - gram ___ diplococci
- H. influenzae = gram ___ coccobacilli
- bacterial
- atypical, viral
- 25, 10
- positive
- negative
Microbio Testing and Other Markers
Respiratory Culture
- ___ , can be done with more severe pts (false negatives)
- tracheal aspiration
- bronchoscopy
- bronchoalveolar lavage
Blood Culture
- get __ sets
___ with differential
___, BUN, electrolytes, LFTs
Pulse Ox, O2 sat
Uriniary antigen tests
- ___
- ___ - serogroup 1
Nasopharyngeal PCR Swabs
- ___
- Viral
- controversial
- 2
- WBC
- SCr
- S. pneumoniae
- Legionella pneumophila
- MRSA
T or F: only use cultures (respiratory and blood) if patient is severe
T
Severe CAP - Major Criteria (Need 1)
1) Septic shock requiring ___
2) Respiratory failure requiring ___
- vasopressors
- mechanical ventilation
Severe CAP - Minor Criteria (Need ≥ 3)
- RR of ___ bpm or more
- PaO2/FlO2 ≤ 250 (outpatient)
- ___ inflitrates
- ___ /disorientation
- uremia (BUN ≥ ___ mg/dL)
- Leukopenia (WBC < ___ cells/uL)
- Thrombocytopenia (Plt < ____ /uL)
- hypothermia (temp < ___ C)
- ___ tension requring aggressive fluids
- 30
- multilobar
- confusion
- 20
- 4,000
- 100,000
- 36
- hypotension
Other Tools for CAP
Procalcitonin
- elevated in presence of bacerial infection
- SHOULD NOT be used to determine use for ___ for CAP
- clinically useful in guiding ___ of treatment if obtained throughout hospitalization
- antibiotics
- duration
Other Tools for CAP - Clinical Prediction Tools
Pneumonia Severity Index (PSI)
- utilizies demographics, comorbid diseases, physical exam, and lab findings
- points < 70 = 0.6% 30 day mortality
- points > 90 = 8.2-29.2% 30 day mortality
CURB-65
- ___
- ___ (BUN > 19 mg/dL)
- RR ≥ 30 bpm
- SBP < 90 mmHg, DBP ≤ 60 mmHg
- Age ≥ ___
- confusion
- Uremia
- 65
Treatment - Supportive Measures
- humidified ___
- broncho ___
- fluids
- chest physiotherapy
- oxygen
- bronchodilators
Empiric Therapy - Outpatient
healthy outpatient adults without comorbidities or risk factors for antibiotic resistance
- ___ 1 g PO q8h
- ___ 100 mg PO BID
- macrolide resistance < 25%, ___ 500 mg PO day 1, 250 mg day 2-5
- amoxicillin
- doxycycline
- Z-Pak
Empiric Therapy - Outpatient
outpatient adults with comorbidities
- chronic heart, lung, renal disease; DM; alcoholism; malignancy; asplenia or immunosuppression
Monotherapy
- respiratory fluroquinolone
- ___ 750 mg PO daily
- ___ 400 mg PO daily
Combo Therapy
- Beta-lactams + ___ or ____
Beta-lactams recommended
- ___ 500/125 mg PO q8h or 875/125 mg PO q12h
- ___ 200 mg PO q12h
- ___ 500 mg PO q12h
- levofloxacin
- moxifloxacin
- macrolide, doxycycline
- amox/clav
- cefpodoxime
- cefuroxime
Empiric Therapy - Inpatient
Non-severe CAP
(no MRSA/P. aeruginosa risk factors)
Monotherapy
- respiratory fluroquinolone
- ___ 750 mg PO daily
- ___ 400 mg PO daily
Combo Therapy
- Beta-lactam + ___
Recommended Beta-lactams
- ___ 1.5 g-3 IV q6h
- ___ 1-2 g IV q24h
- ** ___ IV/PO may be used if FQ or macrolide contrindicated
- levofloxacin
- moxifloxacin
- macrolide
- ampicillin/sulbactam (Unasyn)
- ceftriaxone
- doxycycline
Empiric Therapy - Inpatient
Severe CAP
(no MRSA/P. aeruginosa risk factors)
Combo Therapy 1
- respiratory ___ + ___
Combo Therapy 2
- Beta-lactam + ___
Recommended Beta-lactams
- ___ 1.5 g-3 IV q6h
- ___ 1-2 g IV q24h
- ** ___ IV/PO may be used if FQ or macrolide contrindicated
- fluroquinolone, Beta-lactam
- macrolide
- ampicillin/sulbactam
- ceftriaxone
- doxycycline
Empiric Therapy - Inpatient
MRSA Risk Factors
- ~2-14 days post ___
- previous MRSA respiratory infection/isolation
- previous hospitalization and use of IV antibiotics within last ___ days
MRSA Coverage
- ___ target AUC 400-600
- ___ 600 mg IV/PO q12h
- flu
- 90
- vancomycin
- linzolid
Empiric Therapy - Inpatient
P. aeruginosa Risk Factors
- previous P. aeruginosa respiratory infection
- previous hospitalization and use of IV antibiotics within last ___ days
Pseudomonas Coverage
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 1 g IV q8h
- piperacillin/tazobactam
- cefepime
- meropenem
Pathogen Directed Therapy - Streptococcus pneumoniae
Preferred Therapy
- PCN G; ___ (if S to PCN)
- ___ ; Respiratory ___
Alternative Therapy
- Ceftriaxone
- respiratory FQ
- doxycycline
- vancomycin
- linezolid
- amoxicillin
- ceftriaxone, FQ
Pathogen Directed Therapy - Haemophilus influenzae
Preferred Therapy
- ___ / ___ gen cephalosporins
- ___
- ___
Alternative
- FQ
- doxycycline
- macrolide
- 2nd/3rd
- Unasyn
- Augmentin
Pathogen Directed Therapy - Mycoplasma pneumoniae, Chlamydia pneumoniae
Preferred Therapy
- ___
- ___
Alternative Therapy
- FQ
- macrolide
- doxycycline
Pathogen Directed Therapy - Legionella pneumophila
Preferred Therapy
- ___
- ___
Alternative Therapy
- doxycycline
- FQ
- azithromycin
Pathogen Directed Therapy - MSSA
Preferred Therapy
- ___
- ___
Alternative Therapy
- Vancomycin
- Clindamycin
- cefazolin
- nafcillin
Pathogen Directed Therapy - MRSA
Preferred Therapy
- ___
- ___
Alternative Therapy
- Ceftaroline
- TMP/SMX
- Vancomycin
- Linezolid
Pathogen Directed Therapy - Anaerobes
Preferred Therapy
- ____ and inhibitor
- add ___ if using cephalosporin
Alternative Therapy
- Carbapenem
- Clindamycin
- Beta-lactam
- metronidazole
Pathogen Directed Therapy - Enterobacterales
Preferred Therapy
- __ / ___ cephalosporin
- ___
Alternative Therapy
- Beta-lactam and inhibitor
- FQ
- 3rd/4th
- carbapenem
What about Corticosteroids
ONLY recommended with Surviving Sepsis Guidelines when patient has CAP and ___
- septic shock
Duration of CAP Therapy
Ensure clinical stability prior to d/c Abx
- temp ≤ ___ C (afebrile for ___ - ___ hrs)
- HR ≤ ___ bpm
- RR ≤ ___ bpm
- SBP ≥ ___ mmHg
- arterial O2 saturation ≥ ___ % or pO2 ≥ 60 mmHg on room air
- basline mental status
continue Abx until clinical stability for a minimum of ___ total days
- 38, 24-48
- 100
- 24
- 90
- 90
- 5
T or F: there is a definition to differentiate aspiration pneumonia vs pnemonia
- recommend against ___ coverage unless lung abscess or empyema present
FALSE - same thing
- anaerobic
What would be the most appropriate regimen for outpatient therapy for ST?
A) moxifloxacin 400 mg PO daily
B) Ceftriaxone 1 g IV daily + doxycycline 100 mg PO BID
C) Cefpodoxime 200 mg PO BID + doxycycline 100 mg PO BID
D) amoxicillin/clavulanate 875/125 PO BID + azithromycin 500 mg PO daily
C) Cefpodoxime 200 mg PO BID + doxycycline 100 mg PO BID
What would be the most appropriate regimen for this patient?
A) Linezolid 600 mg IV q12h + Cefepime 2 g IV q8h + Azithromycin 500 mg IV q24h
B) Vancomycin 1250 mg IV q24h + Ceftriaxone 1 g IV q24h + Doxycycline 100 gm IV BID
C) Levofloxacin 750 mg IV q24h + Ceftrixone 1 g IV q24h
D) Vancomycin 1 g IV q24h + piperacillin/tazobactam 4.5 g IV q6h
A) Linezolid 600 mg IV q12h + Cefepime 2 g IV q8h + Azithromycin 500 mg IV q24h
Add linezolid due to MRSA risk with rehospitalization
Definitions
HAP = pneumonia occuring ≥ ___ hours after hospital admission
VAP = pneumonia occuring ≥ 48 hours after ___ ___
HCAP = any pt hospitalized for ≥ __ days within the past 90 days of infection; resides in nursing home or LTCF; received recent IV ___ , ___ , or wound care within the past 30 days if infection; ___
- this is old news tho
- 48
- endotracheal intubation
- 2, Abx, chemotherapy, hemodialysis
HCAP
Previously part of 2005 HAP/VAP guidelines
Since then, ___ to be at an increased risk for multidrug-resistant organisms
- increase use of broad-spectrum Abx without an improvement in outcomes
- may lead to resistance
Moved towards treating as CAP and evaluating for risk factors of ___ and ___
- disproven
- MRSA
- P. aeruginosa
Epidemiology + Impact
HAP
- one of the most ___ hospital-accquired infections
- 1.87% 60 day mortality risk
VAP
- impacts 5-40% of patients on mechanical ventilation > __ days
- increases utilization of healthcare resources
- prolongs length of mechanical ventilation by ~ __ days and hospitalization by ~ __ days ($40,000 per VAP incident)
- common
- 2
- 9
- 12
Pathogenesis
micro-aspiration of oropharyngeal secretions that are colonized with bateria
- usually aerobic gram ___ bacteria
- after 3-5 days of hospitalization, converts to gram ___ organisms
Aspiration of esophageal/gastric content
Hematogenous spread from another source
Direct inoculation into airways via ___ by healthcare personnel
Mechanical ventilation - endotracheal tube ___ all host defenses and decreases LRT defenses
- positive
- negative
- intubation
- bypasses
Risk Factors for HAP/VAP
- advanced ___
- severity of comorbid diseases
- duration of ___
- endotracheal intubation
- nasgoastric tube
- altered ___ status
- surgery previous ___ therapy
- age
- hospitalization
- mental
- antimicrobial
Diagnosis of HAP/VAP
No gold standard for diagnosis
Timing
- important for defining ___ -acquired infection
- impacts choice of antibiotics
Typical Presentation
- New lung ___ + clinical signs and symptoms
- new onset ___ , purulent sputum, ___ , decline in ___
- hospital
- infiltrate
- fever, leukocytosis, oxygenation
Common Pathogens - HAP/VAP
___ gram ___ bacilli = ~70%
- pseudomonas aeruginosa = 10-20%
- enteric gram-negative bacilli = 20-40%
- Acinetobacter baumannii = 5-10%
___ = 20-30%
- MRSA greater concern in this population
- aerobic, negative
- Staphylococcus aureus
Microbiology Testing - HAP/VAP
___ Cultures
- recommended obtaining for all pts
- non-invasive > invasive
- invasive respiratory cultures have diagnostic threshold
___ Cultures
- obtain from all patients
Respiratory
Blood
Risk Factors for MDP
MDR HAP/MRSA HAP/ VAP
- prior IV Abx use within ___ days
MDR VAP
- prior IV Abx use within ___ days
- ___ shock at time of diagnosis
- ___ prior to diagnosis
- acute ___ replacement therapy prior to VAP onset
- ≥ 5 days of ___ prior to diagnosis
MDR P. aeruginosa
- prior IV antibiotic use within ___ days
- ___ , broad spectrum beta-lactams, FQs
MDR HAP/MRSA HAP/ VAP
- 90
MDR VAP
- 90
- septic
- ARDS
- renal
- hospitalization
MDR P. aeruginosa
- carbapenems
- 90
Empiric Therapy - The Principles
Empiric regimens should be based on ___ distribution of pathogens and susceptibility
- Utilize yearly antiobiogram
If possible, data should stratify for populations such as VAP or ICU population
Goal = provide ___ ___ antibiotics while avoiding unnecessary harms of inappropriate coverage
- local
- broad spectrum
Empiric Therapy - Antiobitic Choice: MRSA Coverage
Risk Factors
- typical risk factors
- ICUs where > __ - __ % MRSA isolates
- Treatment where prevalence is ___
Treatment:
- ___ AUC 400-600
- ___ 600 mg PO/IV q12h
- 10-20
- unknown
- Vancomycin
- Linezolid
Empiric Therapy - Antiobitic Choice: P. aeruginosa Coverage
Risk Factors for Resistance
- ICUs where > ___ % of isolates resistant
- Treatment where resistance rates are ___
Treatment:
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 500 mg IV q6h
- ___ 1 g IV q8h
- ___ 750 mg IV q24h
- 10%
- unknown
- piperacillin/tazobactam
- cefepime
- imipenem
- meropenem
- levofloxacin
Empiric Therapy - HAP
Not at High Risk for Mortality
- (aka not on ___ support or ___ shock)
Goal
- provide coverage for MSSA + P. aeruginosa
Treatment
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 500 mg IV q6h
- ___ 1 g IV q8h
- ___ 750 mg IV q24h
- ventilatory, septic
- piperacillin/tazobactam
- cefepime
- imipenem
- meropenem
- levofloxacin
Empiric Therapy - HAP
Not at High Risk for Mortality but MRSA risk
- (aka not on ___ support or ___ shock)
Goal
- provide coverage for MRSA + P. aeruginosa
Combo Treatment (A + B)
Treatment A
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 500 mg IV q6h
- ___ 1 g IV q8h
- ___ 750 mg IV q24h
PLUS
Treatment B
- ___ AUC 400-600
- ___ 600 mg IV q12h
Treatment A
- piperacillin/tazobactam
- cefepime
- imipenem
- meropenem
- levofloxacin
Treatment B
- vancomycin
- linezolid
Empiric Therapy - HAP
High Risk for Mortality and MRSA risk
- on ___ support or ___ shock
Goal
- provide coverage for MRSA + MDR P. aeruginosa
Combo Therapy
Treatment A (Pick 2 from Different Classes)
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 500 mg IV q6h
- ___ 1 g IV q8h
- ___ 750 mg IV q24h
- ___ / ___ IV
PLUS
Treatment B
- ___ AUC 400-600
- ___ 600 mg IV q12h
- ventilatory, septic
- piperacillin/tazobactam
- cefepime
- imipenem
- meropenem
- levofloxacin
- tobramycin/amikacin
- Vancomycin
- Linezolid
Empiric Therapy - VAP
Goal
- Provide coverage for MRSA + P. aeruginosa
Choose __ anti-pseudomonals when there are risk factors for resistance
Combo Treatment (A +B)
Treatment A
- ___ 4.5 g IV q6h
- ___ 2 g IV q8h
- ___ 500 mg IV q6h
- ___ 1 g IV q8h
- ___ 750 mg IV q24h
- ___ / ___ IV
PLUS
Treatment B
- ___ AUC 400-600
- ___ 600 mg IV q12h
- piperacillin/tazobactam
- cefepime
- imipenem
- meropenem
- levofloxacin
- tobramycin/amikacin
- Vancomycin
- Linezolid
Non-Beta Lactam Considedrations
T or F: Daptomycin is used for LRTI
FALSE - never
Non-Beta Lactam Considedrations
Daptomycin
- never use
Aminoglycosides
- dont use as ___
- avoid empiric use unless necessary
- poor ___ penetration, nephrotoxicity, ototoxicity, reports of lower clinical response rates
Polymyxins
- avoid empiric use if possible
- reserve for pts with high prevalence of ___ pathogens
- significant ___
Tigecycline
- great for ___ infections
- associated with increased ___
- monotherapy, lung
- MDR, nephrotoxicity
- polymicrobial, mortality
Pathogen-Specific Therapy
MSSA (2)
- cefazolin
- nafcillin
Pathogen-Specific Therapy
Enterbacterales (1)
- 3rd gen cephjalosporins
Pathogen-Specific Therapy
ESBL-producer (2)
- carbapenem
- ceftazidime/avibactam
Pathogen-Specific Therapy
KPC-producer (3)
- meropenem/vaborbactam
- imipenem/relebactan
- ceftazidime/avibacam
Pathogen-Specific Therapy
NDM/VIM-producer (2)
- Ceftazidime/avibactam + aztreonam
- cefiderocol
Pathogen-Specific Therapy
acinetobacter spp. (3)
- carbapenem
- ampicillin/sulbactam
- cefiderocol
Duration for HAP/VAP
- ___ day duration if clinically stable
VAP
- compared to longer durations in VAP, there is no difference in duration of MV, hospital LOS, treatment failurem recurrent pneumonia, or mortality
HAP
- no significant differences compared to longer durations
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