Transcript Community Acquired Pneumonia

Community-Acquired
Pneumonia
Objectives





Describe the common pathogenesis and
pathogens of pneumonia
Discuss diagnosis and initial management of
community acquired pneumonia (CAP)
Understand features of the Pneumonia PORT
Severity Index
Discuss the IDSA/ATS guidelines and
recommendations for final antibiotic choice
Understand issues in basic management for
pneumonia in children, nursing home patients,
and immunocompromised patients.
Epidemiology

Unclear! Few population-based statistics on the
condition alone
 CDC combines PNA with influenza for morbidity
& mortality data





PNA & influenza = 7th leading causes of death in the
US (2001)
Age-adjusted death rate = 21.8 per 100,000
Mortality rate: 1-5% out-Pt, 12% In-Pt, 40% ICU
Death rates increase with comorbidity and age
Affects race and sex equally
Community Acquired
Pneumonia
 Infection
of the lung parenchyma in a
person who is not hospitalized or living
in a long-term care facility for ≥ 2 weeks
 5.6 million cases annually in the U.S.
 Estimated total annual cost of health care
= $8.4 billion
 Most common pathogen = S. pneumo (6070% of CAP cases)
“Nosocomial” Pneumonia
 Hospital-acquired

pneumonia (HAP)
Occurs 48 hours or more after admission,
which was not incubating at the time of
admission
 Ventilator-associated

pneumonia (VAP)
Arises more than 48-72 hours after
endotracheal intubation
“Nosocomial” Pneumonia

Healthcare-associated pneumonia (HCAP)


Patients who were hospitalized in an acute care
hospital for two or more days within 90 days of the
infection; resided in a nursing home or LTC facility;
received recent IV abx, chemotherapy, or wound care
within the past 30 days of the current infection; or
attended a hospital or hemodialysis clinic
Guidelines for the Management of Adults with
HAP, VAP, and HCAP. American Thoracic
Society, 2005
Pathogenesis
 Inhalation,
aspiration and hematogenous
spread are the 3 main mechanisms by
which bacteria reaches the lungs
 Primary inhalation: when organisms
bypass normal respiratory defense
mechanisms or when the Pt inhales
aerobic GN organisms that colonize the
upper respiratory tract or respiratory
support equipment
Pathogenesis
 Aspiration:
occurs when the Pt aspirates
colonized upper respiratory tract
secretions

Stomach: reservoir of GNR that can ascend,
colonizing the respiratory tract.
 Hematogenous:
originate from a distant
source and reach the lungs via the blood
stream.
Pathogens
 CAP
usually caused by a single organism
 Even with extensive diagnostic testing,
most investigators cannot identify a
specific etiology for CAP in ≥ 50% of
patients.
 In those identified, S. pneumo is causative
pathogen 60-70% of the time
Streptococcus pneumonia
 Most
common cause of CAP
 Gram positive diplococci
 “Typical” symptoms (e.g. malaise, shaking
chills, fever, rusty sputum, pleuritic hest
pain, cough)
 Lobar infiltrate on CXR
 Suppressed host
 25% bacteremic
Atypical Pneumonia





#2 cause (especially in younger population)
Commonly associated with milder Sx’s:
subacute onset, non-productive cough, no focal
infiltrate on CXR
Mycoplasma: younger Pts, extra-pulm Sx’s
(anemia, rashes), headache, sore throat
Chlamydia: year round, URI Sx, sore throat
Legionella: higher mortality rate, water-borne
outbreaks, hyponatremia, diarrhea
Viral Pneumonia
 More

common cause in children
RSV, influenza, parainfluenza
 Influenza
most important viral cause in
adults, especially during winter months
 Post-influenza pneumonia (secondary
bacterial infection)

S. pneumo, Staph aureus
Other bacteria

Anaerobes


Gram negative




Aspiration-prone Pt, putrid sputum, dental disease
Klebsiella - alcoholics
Branhamella catarrhalis - sinus disease, otitis, COPD
H. influenza
Staphylococcus aureus

IVDU, skin disease, foreign bodies (catheters,
prosthetic joints) prior viral pneumonia
Diagnosis and Management
Guidelines

American Thoracic Society


Infectious Diseases Society of America


Guidelines for the Management of Adults with CA
(2001)
Update of Practice Guidelines for the Management of
CAP in Immunocompetent adults (2003)
ATS and IDSA joint effort

IDSA/ATS Consensus Guidelines on the Management
of CAP in Adults (March 2007)
Guidelines
 2001 ATS
& 2003 IDSA Guideline Update
 Expert panels
 Evidence-based recommendations
 Recommend patient stratification to
identify likely pathogens and suggested
empiric abx



Site of care
Presence of cardiopulmonary disease
Presence of “modifying factors”
Clinical Diagnosis
 Suggestive
signs and symptoms
 CXR or other imaging technique
 Microbiologic testing
Signs and Symptoms










Fever or hypothermia
Cough with or without sputum, hemoptysis
Pleuritic chest pain
Myalgia, malaise, fatigue
GI symptoms
Dyspnea
Rales, rhonchi, wheezing
Egophony, bronchial breath sounds
Dullness to percussion
Atypical Sx’s in older patients
Clinical Diagnosis: CXR
 Demonstrable
infiltrate by CXR or other
imaging technique



Establish Dx and presence of complications
(pleural effusion, multilobar disease)
May not be possible in some outpatient
settings
CXR: classically thought of as the gold
standard
Infiltrate Patterns
Pattern
Possible Diagnosis
Lobar
S. pneumo, Kleb, H. flu,
GN
Atypicals, viral,
Legionella
Viral, PCP, Legionella
Patchy
Interstitial
Cavitary
Large effusion
Anaerobes, Kleb, TB, S.
aureus, fungi
Staph, anaerobes, Kleb
Clinical Diagnosis:
Recommended testing
 Outpatient:
CXR, sputum Cx and Gram
stain not required
 Inpatient: CXR, Pox or ABG, chemistry,
CBC, two sets of blood Cx’s


If suspect drug-resistant pathogen or
organism not covered by usual empiric abx,
obtain sputum Cx and Gram stain.
Severe CAP: Legionella urinary antigen,
consider bronchoscopy to identify pathogen
Clinical Diagnosis
 Assess
overall clinical picture
 PORT Pneumonia Severity Index (PSI)


Aids in assessment of mortality risk and
disposition
Age, gender, NH, co-morbidities, physical
exam lab/radiographic findings
IDSA: Outpt Management in
Previously Healthy Pt

Organisms: S. pneumo, Mycoplasma, viral,
Chlamydia pneumo, H. flu
 Recommended abx:


Advanced generation macrolide (azithro or clarithro)
or doxycycline
If abx within past 3 months:



Respiratory quinolone (moxi-, levo-, gemi-), OR
Advanced macrolide + amoxicillin, OR
Advanced macrolide + amoxicillin-clavulanate
IDSA: Outpt Management in
Pt with comorbidities

Comorbidities: cardiopulmonary dz or
immunocompromised state
 Organisms: S. pneumo, viral, H. flu, aerobic GN
rods, S. aureus
 Recommended Abx:


Respiratory quinolone, OR advanced macrolide
Recent Abx:


Respiratory quinolone OR
Advanced macrolide + beta-lactam
IDSA: Inpt ManagementMedical Ward

Organisms: all of the above plus polymicrobial
infections (+/- anaerobes), Legionella
 Recommended Parenteral Abx:



Respiratory fluoroquinolone, OR
Advanced macrolide plus a beta-lactam
Recent Abx:

As above. Regimen selected will depend on nature of
recent antibiotic therapy.
IDSA: Inpt ManagementSevere/ICU
 One


Mechanical ventilation
Septic shock, OR
 Two



of two major criteria:
of three minor criteria:
SBP≤90mmHg,
Multilobar disease
PaO2/FIO2 ratio < 250
 Organisms:
S. pneumo, Legionella, GN,
Mycoplasma, viral, ?Pseudomonas
IDSA: Inpt Management:
Severe/ICU

No risk for Pseudomonas

IV beta-lactam plus either
• IV macrolide, OR IV fluoroquinolone

Risk for Pseudomonas

Double therapy: selected IV antipseudomonal betalactam (cefepine, imipenem, meropenem,
piperacillin/tazobactam), plus
• IV antipseudomonal quinolone
-OR-

Triple therapy: selected IV antipseudomonal betalactam plus
IV aminoglycoside plus either
IV macrolide, OR IV antipseudomonal quinolone
Switch to Oral Therapy
 Four




 If
criteria:
Improvement in cough and dyspnea
Afebrile on two occasions 8 h apart
WBC decreasing
Functioning GI tract with adequate oral intake
overall clinical picture is otherwise
favorable, can can switch to oral therapy
while still febrile.
Management of Poor
Responders
 Consider
non-infectious illnesses
 Consider less common pathogens
 Consider serologic testing
 Broaden antibiotic therapy
 Consider bronchoscopy
Prevention
 Smoking
cessation
 Vaccination per ACIP recommendations

Influenza
• Inactivated vaccine for people >50 yo, those at risk
for influenza compolications, household contacts of
high-risk persons and healthcare workers
• Intranasal live, attenuated vaccine: 5-49yo without
chronic underlying dz

Pneumococcal
• Immunocompetent ≥ 65 yo, chronic illness and
immunocompromised ≤ 64 yo
Pneumonia in Children: Dx

Symptoms

Infants: non-specific manifestations
• Fever, poor feeding, irritability, vomiting, diarrhea, URI Sx,
cough, respiratory distress

Older children: more specific
• Fever, cough, chest pain, tachypnea, tachycardia, grunting,
nasal flaring, retracting. Cyanosis usually very late.

Signs/Physical exam



RR > 60 for all ages
Hypoxia
Rales, wheezes, crackles, coarse breath sounds
Pneumonia in Children:
Pathogens
 0-4
wks: GBS, GN enterics, Listeria
 4-12 wks: C. trachomatis, GBS, GN
enterics, Listeria, viral
(RSV/parainfluenza), B. pertussis
 3 mos-4 yrs: Viral, S. pneumo, H.
influenza, M. catarrhalis, Grp A Strep,
Mycoplasma
 > 5yrs: Mycoplasma (5-15yrs), C. pneumo,
S. pneumo, viral
Pneumonia in the Elderly

Prevention important
 Presentation can be subtle
 Antibiotic choice in CAP is same as other adults
 Healthcare associated pneumonia

Consider S. aureus (skin wounds) and GN bacteria
(aspiration)
• Pneumonia in Older Residents of Long-term Care Facilities.
AFP 2004; 70: 1495-1500.
Pneumonia in
Immunocompromised Pts

Smokers, alcoholics, bedridden, immunocompromised, elderly
 Common still common



S. pneumo
Mycoplasma
Pneumocystis Carinii Pneumonia





P. jirovecii
Fever, dyspnea, non-prod cough (triad 50%),
insidious onset in AIDS, acute in other
immunocompromised Pts
CXR: bilateral interstitial infiltrates
Steroids for hypoxia
TMP-SMZ still first line