Community-Acquired

Pneumonia
Joanna M. Delaney, D.O.
Georgetown University /
Providence Hospital
June 8, 2007
 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 (60-
70% 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
 Aspiration-prone Pt, putrid sputum, dental disease
 Gram negative
 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
 Guidelines for the Management of Adults with CA
(2001)
 Infectious Diseases Society of America
 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
Patchy Atypicals, viral,
Legionella
Interstitial Viral, PCP, Legionella

Cavitary Anaerobes, Kleb, TB, S.

aureus, fungi
Large effusion 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 Management-
Medical 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 Management-
Severe/ICU
 One of two major criteria:
 Mechanical ventilation
 Septic shock, OR
 Two 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 beta-lactam
(cefepine, imipenem, meropenem, piperacillin/tazobactam),
plus
• IV antipseudomonal quinolone
-OR-
 Triple therapy: selected IV antipseudomonal beta-lactam
plus
IV aminoglycoside plus either
IV macrolide, OR IV antipseudomonal quinolone
 Switch to Oral Therapy
 Four criteria:
 Improvement in cough and dyspnea
 Afebrile on two occasions 8 h apart
 WBC decreasing
 Functioning GI tract with adequate oral intake
 If 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, immuno-
compromised, 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
New Guideline
 IDSA/ATS 2007 Guideline
 Hospital Admission Decision
 CURB-65 criteria (confusion, uremia, RR, low BP, age
65 yrs or greater) or PSI can be used to ID candidates
for outpt management
 Diagnostic Testing
 Acknowledges the low yield and infrequent positive
impact on clinical care
 Outpt testing for etiologic Dx remain optional
 Inpt testing for etiologic Dx recommended for specific
indications
 Antimicrobial therapy: essentially unchanged
 Summary
 Use overall clinical presentation to guide
therapy
 The admission decision is an “art of
medicine” decision
 Use risk factors and guidelines to assist
with clinical judgement
 References
American Thoracic Society. Guidelines for the Management of Adults with
Community-acquired Pneumonia. Am J Respir Crit Care Med 2001 Vol.
163:1730-1754.

Mandell LA, Bartlett JG, Dowell SF, File TM Jr, Musher DM, Whitney C.
Update of practice guidelines for the management of community-acquired
pneumonia in immunocompetent adults. Clin Infect Dis 2003 Dec
1;37(11):1405-33.

Mandell LA, Wunderink RG, Anzueto A, Bartlett JG, Campbell GD, Dean
NC, Dowell SF, File TM Jr, Musher DM, Niederman MS, Torres A,
Whitney CG. Infectious Diseases Society of America/American Thoracic
Society consensus guidelines on the management of community-acquired
pneumonia in adults. Clin Infect Dis 2007 Mar 1;44 Suppl 2:S27-72.

Arch Ped Adol Med 1995; 149: 283-7.