Community-Acquired Pneumonia

Nilesh Patel, D.O.

October 8, 2008

St. Joseph’s Regional Medical Center

Emergency Medicine Conference

Objectives

Epidemiology Pathophysiology Signs/Symptoms Diagnostics Treatments Disposition

Questions we will answer…

What is the definition of CAP? What are the most common organisms in CAP? Do blood cultures affect management? What is the optimal timing of antibiotic therapy in

CAP? What are the antibiotic choices for CAP? What are the admission criteria? Who can go

home?

Other

Next hour…– Atypical pneumonias– Viral pneumonias– PCP/Other fungal pneumonias

What we will not talk about…– Pediatric pneumonias– HAP/HCAP

Community-Acquired Pneumonia (CAP): Definition

Infection of pulmonary parenchyma Pneumonia acquired in the community

– Excludes hospitals (HAP)– Excludes extended care facilities (HCAP)– Typical– Atypical

Epidemiology

4 million cases/year in U.S. 600,000 - 1 million hospitalizations 12 cases per 1,000 adults/year 6th leading cause of death in U.S. Leading cause of death due to infectious

cause Mortality ranges from 1-20% Mortality increased in certain populations

Pathophysiology

Aspiration of oropharyngeal organisms Inhalation of infected aerosols Hematogenous spread from extra-

pulmonary sites Contiguous spread Direct inoculation

Pathophysiology

Lobar pneumonia Interstitial pneumonia Bronchopneumonia Multi-lobar pneumonia Cavitary pneumonia Necrotizing pneumonia Lung Abscess

Pathophysiology TYPICAL Organisms

– Streptococcus pneumoniae– Haemophilus influenza– Streptococcus pyogenes– Klebsiella pneumoniae– Moraxella catarrhalis– Staph aureus– Enterobacteriaceae/Gram negative bacilli

Anaerobic organisms (aspiration)– Fusobacterium sp.– Prevotella sp.– Bacteroides sp.

Pathophysiology

ATYPICAL Organsims– Mycoplasma pneumoniae– Chlamydia pneumoniae– Chlaymida sp.– Legionella sp.– Respiratory viruses– Others

Pathophysiology

Strep pneumo

Strep pneumo

Gram positive lancet-shaped, encapsulated diplococcus

“Most common cause of CAP” Multiple serotypes High mortality if untreated >> Sepsis

Strep pneumo Signs/Symptoms

– Abrupt onset/ill appearance– Cough (rust colored sputum)– Fever/Chills– Chest pain/SOB– Tachypnea/Tachycardia

CXR– Lobar infiltrate– Bulging fissure

Treatments– PCN– Cephalosporin– Macrolide

Strep pneumo

H flu

H flu

Gram negative pleomorphic rods Encapsulated/Unencapsulated forms Serotypes a-f “2nd most common cause of CAP” Common pathogen in COPD patients May also lead to sepsis

H flu Signs/Symptoms

– Immunosuppresed/Debilitated patient– Productive cough– Fever– Chest pain– SOB

CXR– Patchy alveolar infiltrates

Treatment– Cephalosporins– Augmentin– Macrolide (Azithromycin)– Fluroquinolones

H flu

H flu

H flu

Symptoms/Signs (Typicals)

Productive cough Shortness of breath Chest pain Subjective fever/chills N/V Back pain Abdominal pain

Abnormal VS Rales/Rhonchi/Wheez Decreased breath

sounds Dullness to percussion Increased tactile

fremitus Bronchial breath

sounds Egophany

Symptoms/Signs (Atypicals)

Dry Cough Chest pain/SOB Extra-pulmonary

symptoms; Constitutional symptoms– N/V/D

– Headache

– Myalgias

– Fatigue

+- Abnormal VS Rales/Rhonchi/Wheez

Symptoms/Signs

American Journal of EM 2006: 25, 631-36– Retrospective, multi-center– 421 patients diagnosed with CAP– VS abnormalities were most significant

predictors of CAP– Hypoxia had strongest association– Greater # of VS abnormalities >> Higher

prevalence of CAP– Age also significantly associated with CAP

Diagnostics Labs

– CBC– BMP

Imaging– CXR– CT scans

Cultures– Blood – Sputum

Other tests– ABG/EKG– Urine antigen tests

Diagnostics

IV

Oxygen

Monitor (pulse ox)

Diagnostics: WBC count

WBC count

– Normal count does not r/o pneumonia

– Elevated/Decreased >> Bacterial pneumonia

– Look for Left Shift!

Diagnostics: CXR Findings

– Infiltrates– Pleural effusions– Abscess’/Cavities– Bulging fissures– Atelectasis– Air bronchograms

Other findings– PTX– Pleural thickening/Scarring– Pulmonary edema– Lymphadenopathy/Masses

Diagnostics: CXR Normal CXR

– Immunocompromised– Dehydrated– Early infection

American Journal of Medicine Sept. 2004: 117, 305-11– 2706 patients– 911 patients with pneumonia and (–)CXR– These patients were older, increased co-morbidities– These patients had similar rates of + sputum/blood cultures– These patients had a similar mortality

Diagnostics: CXR

Respiratory Medicine May 2006: 100, 926-32– 192 patients with pneumonia– Excellent IR for lobes involved, extent of

infiltrate, pleural effusion– Poor IR for pattern of infiltrate– Minimal relation found between cultured

pathogens and radiologic features of infiltrate on CXR

Diagnostics: CT scan

CT scan– Alternative diagnoses– Unresolved cases– Complications suspected– Concerning CXR– Treatment failure

Diagnostics: Cultures Sputum gram stain/culture

– Change antibiotic therapy– Unusual pathogens/antibiotic resistance issues

– Do not change antibiotics/outcomes– Cost– Process issues

Sputum cultures?– Are sputum cultures useful in ED?– Are sputum cultures useful in ICU?– Do antibiotics affect yield of sputum?

Diagnostics: Cultures Sputum cultures: Recommendations

– Outpatient• Optional

– Inpatient• Optional• Recommended when result may change therapy

– Recommended• ICU admission/Severe CAP• Failure of outpatient therapy• Cavitary infiltrates (suspect TB)• Alcoholism• Severe COPD• Pleural effusion• Positive urinary antigen for Legionella/Strep pneumo

Diagnostics: Cultures Blood Cultures

– Yield pathogen 5-15%– Blood cultures often do not change management– Most commonly isolated organism…Strep pneumo– High false positive rate– Yield of blood cultures decreased by 50% by prior antibiotic

therapy– Optional– Recommended

• Severe CAP• Immunodeficient states (asplenia, liver disease, HIV)• Indications for sputum cultures• Chest 2003

Diagnostics: Cultures

Blood Cultures– Chest 2003: 123, 1142-1150– Emergency Medicine Journal 2003: 20, 521-23– Emergency Medicine Journal 2004: 21, 446-48– Academic Emergency Medicine June 2006: 13,

740-45– Journal of Emergency Medicine July 2007: 33,

1-8

Treatments

Supportive therapies Antibiotics (outpatient/inpatient) ICU therapies Antibiotic resistance Timing to antibiotics (6 hours)

Treatments Annals of Emergency Medicine July 2001: 38,

107-113…”Clinical Policy for the Management and Risk Stratification of CAP in Adults in the Emergency Department”– www.acep.org

Clinical Infectious Disease March 2007: 44, S27-72…”Infectious Disease Society of America/ATS Consensus Guidelines on the Management of CAP”

Treatments: Basics/Supportive

ABCs IV/Oxygen/Monitor Albuterol nebulized BIPAP Intubation IVF Steroids

Treatments: Antibiotics

Empiric Antibiotics– Based on most likely pathogen– Local antimicrobial resistance patterns– Antibiotics recommended by class

Pathogen specific Antibiotics– Consider specific risk factors

Treatments: Antibiotics

Outpatient

Healthy patients– MACROLIDE (Zithromax, Clarithromycin)– DOXYCYCLINE

Co-morbid patients– BETA LACTAM + MACROLIDE– FLUOROQUINOLONE (Avelox, Levaquin)

Treatments: Antibiotics

Inpatient

FLUOROQUINOLONE (Levaquin, Avelox)

BETA LACTAM + MACROLIDE (Ceftriaxone/Cefotaxime + Zithromax)

Treatments: Antibiotics

Inpatient, ICU BETA LACTAM (Ceftriaxone/ Cefotaxime/Unasyn)

+ Either MACROLIDE or FLUOROQUINOLONE PCN allergic: AZTREONAM +

FLUOROQUINOLONE Pseudomonas

– ZOSYN, CEFEPIME, IMIPENEM, MEROPENEM + FLUOROQUINOLONE OR MACROLIDE + AMINOGLYCOSIDE

CA-MRSA– Add VANCOMYCIN or LINEZOLID

Treatments: Antibiotics

Anaerobic coverage– Not needed in majority of CAP cases– Indications

• Classic aspiration syndromes• LOC• Drug/ETOH overdose• Seizure• Hx of gingival disease/Esophageal dysmotility

– Antibiotics• CLINDAMYCIN or FLAGYL

Treatments: Antibiotic Resistance

Drug-resistant Strep pneumo (DRSP)

Community-acquired Methicillin resistant Staph aureus (CA-MRSA)

Timing to Antibiotics “Lots of Press”…JCAHO/CMS JAMA 1997

– Decreased mortality in patients > 65 y/o antibiotics within 8 hours

Archives of IM 2004– Decreased mortality antibiotics within 4 hours

2008???

Timing to Antibiotics

Chest March 2007: 131, 1865-69 Annals of EM: May 2007: 49, 553-59 Annals of EM: May 2007: 49, 561-63 Clinical Infectious Disease March 2007: 44, S27-

72– “Do not recommend a specific time window for

delivery of first antibiotic dose”

ACEP News July 2007…”Studies Challenge 4-Hour Antibiotic Guideline for CAP”

Timing to Antibiotics

Physician…Antibiotics should be administered as soon as possible once CAP is diagnosed/considered likely

JCAHO…Antibiotics within 6 hours for CAP

Disposition WHO STAYS…WHO CAN WE

DISCHARGE???

NEJM January 1997: 336, 243-50– PORT cohort study– Prediction rule derived in 14,000 patients– Prediction rule validated in 40,000 patients– Predicts patients with increased 30 day mortality– Helps ER physicians with admission/discharge

decisions– PNEUMONIA SEVERITY INDEX (PSI)

Disposition

CURB-65 criteria (British Thoracic Society)….1,068 patients– Confusion– Uremia– Respiratory rate– Blood pressure (low)– > 65 y/o

CAP 2008

Epidemiology of CAP has remained stable Typicals and atypicals—the lines are blurred Patient risk factors Diagnostics

– WBC count

– Sputum cultures

– Blood cultures

– Urine antigen tests

CAP 2008

Treatment– Outpatient (healthy, co-morbid)– Inpatient– Inpatient (ICU, risk factors)– HAP, HCAP (ask the ?’s)

ED treatment considerations– Empiric coverage– Blood cultures prior to antibiotic therapy– Antibiotics in 6 hours

Drug resistance– DRSP, CA-MRSA– CA-MRSA

Summary Epidemiology

– Common problem Pathophysiology

– Strep pneumo most common– Typicals/Atypicals

Signs/Symptoms– Cough (productive, nonproductive)– SOB/cp– Fever– Abnormal VS– Abnormal lung exam

Summary Diagnostics

– CXR with infiltrate– Sputum GS/cultures– Blood cultures

Treatments– ABC– IV/O2/Monitor– Antibiotics

Disposition– PSI, Curb-65 criteria