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  6 th 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 Prevotella

sp.

Bacteroides

sp.

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  “2 nd 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 FLUOROQUINOLONE  PCN allergic: AZTREONAM FLUOROQUINOLONE +  or 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

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