Pneumonia, Community-Acquired — ED/Inpatient Diagnostic Testing — Clinical Pathway: All Settings

Community Acquired Pneumonia Clinical Pathway — All Settings

ED/Inpatient Diagnostic Testing

Recommended

Chest X-ray

CXR findings do not consistently alter patient management and they do not differentiate viral from bacterial etiology. Typical findings may be absent in early disease or in patients with significant dehydration.

Sometimes Recommended

CBC w/diff

Blood Culture

For patients with severe or complicated pneumonia, or patients worsening on antibiotic therapy.

Mycoplasma PCR

If M. pneumoniae is suspected.

Features of Mycoplasma infections:

  • Insidious onset; usually 5-7 days before presentation
  • Headache, malaise, sore throat, prominent cough
  • Diffuse, bilateral, interstitial infiltrates on x-ray
  • Diffuse rales on auscultation
  • Age > 5

M. pneumoniae is known to cause pneumonia but it is unknown whether antibiotic treatment is beneficial in improving clinical outcomes. Additionally, positive M. pneumoniae PCR tests are common in asymptomatic hosts

Sputum Bacterial Culture

For patients that can produce a sputum sample AND have severe or complicated pneumonia OR in children requiring intubation for suspected bacterial CAP.

Nasal MRSA Screening

Consider nasal MRSA screening culture for those with severe/complicated pneumonia started empirically on clindamycin/vancomycin. Anti-MRSA therapy can generally be stopped in patients who do not grow MRSA. Susceptibilities can be performed upon request in positive cases.

Respiratory viral testing (non-influenza viruses)

Send viral testing only if a viral etiology is thought to be the sole cause of disease and detecting a virus will change management.

Influenza testing (applicable only during flu season)

For ED patients, please see the ED Influenza Pathway. For inpatients, consider obtaining influenza testing to determine the need for oseltamivir. Two options are available for inpatient influenza testing during flu season:

  • Flu/RSV PCR only
  • Flu/RSV PCR with reflex to the full panel if flu/RSV testing is negative (select this option if detecting any non-influenza virus will change management)

Not Routinely Recommended

  • Erythrocyte sedimentation rate (ESR)
  • C-reactive protein (CRP)
  • Procalcitonin (PCT)