Sickle cell disease (acute chest syndrome)

Last revised by Dr Yuranga Weerakkody on 14 Mar 2021

Acute chest syndrome (ACS) in sickle cell disease is a leading thoracic complication - as well as leading cause of mortality - in those affected by sickle cell disease. The diagnosis is made on the combination of new pulmonary opacity on chest x-ray with at least one new clinical symptom or sign. 

For a general discussion of sickle cell disease, please refer to sickle cell disease.

Patients may present with acute fever, cough, wheezing, tachypnea and/or chest pain on a background of established sickle cell disease. 

There is no single underlying etiology to acute chest syndrome but rather a variety of infectious and noninfectious causes, including 5:

Typically seen as segmental or subsegmental atelectasis/consolidation with a lower lobe predilection, and/or pleural effusion

A chest radiograph may also show other sequelae from sickle cell disease such as bone infarcts, rib enlargement and cardiomegaly (from anemia).  

Point-of-care lung ultrasonography in the acute chest syndrome may reveal one of the following patterns;

  • alveolar consolidation
    • the most common abnormality found, with a posterobasal regional predilection
    • air bronchograms may be visualized
  • anterior subpleural consolidations
  • lung rockets
    • three or more B-lines per sonographic field, typically 3 cm apart (B3 lines) - defines the sonographic interstitial syndrome
    • bilateral diffuse anterolateral interstitial syndrome may be observed 7
  • pleural effusions 9

May show a mosaic perfusion pattern that could be associated with a pleural effusion. The radiographic signs above may also be seen on CT.

The term was first proposed in patients with sickle cell disease by Charache et al in 1979 as a description for “the combination of chest pain, fever, increased leukocytosis, and appearance of a new shadow on a chest radiograph.

General imaging differential considerations include:

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: plain radiograph
    Drag here to reorder.
  • Case 1: CT chest
    Drag here to reorder.
  • Case 2
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.