New Chest Imaging Guidance from the World Health Organization

July 31, 2020

A team of international experts published seven recommendations for the use of chest imaging in the diagnosis and management of COVID-19-positive patients.

The World Health Organization (WHO) has published new rapid guidance for using chest imaging for diagnosing and managing patients who test positive for COVID-19.

For two months, international experts shared their knowledge and experience via online meetings and reviews. The result is a concise list of recommendations on how providers can best evaluate the how acceptable, feasible, and effective chest X-ray, chest CT, and lung ultrasound will be in addressing COVID-19.

The team published their guidance in the journal Radiology on July 30.

For diagnosis, the team made three recommendations:

  1. Chest imaging does not offer diagnostic accuracy for asymptomatic COVID-19 patients, and use is not suggested.
  2. Choose RT-PCR, when available and time-effective, over chest imaging in symptomatic COVID-19 patients.
  3. Chest imaging can be used with symptomatic patients in two instances: when the RT-PCR test is either unavailable or results are delayed and when initial RT-PCR results are negative, but there is a high clinical suspicion of COVID-19.

The team made four additional recommendations for chest imaging with patient management:

  1. For patients with suspected or confirmed COVID-19 who have mild symptoms, use chest imaging – alongside lab assessments – to decide between a hospital admission or home recovery.
  2. For patients with confirmed infection and moderate-to-severe symptoms, pair imaging with lab assessments to decide between regular ward or intensive care unit admission.
  3. For hospitalized patients with suspected or confirmed infection and moderate-to-severe symptoms, use chest imaging with lab assessments to inform therapeutic management.
  4. Do not use chest imaging in hospitalized patients whose symptoms have resolved to make a decision regarding discharge.

The team did note that these recommendations were conditional, were based on low-to-very low certainty findings culled from existing studies, and were directed at chest imaging overall rather than specific modalities. Additionally, they said, there is a continual need for more evidence about the diagnostic and prognostic value of imaging modalities in the management of the pandemic.