Initial diagnosis of Macrophage Activation Syndrome

Macrophage activation syndrome (MAS) is a rare hyperinflammatory condition, one of the increasingly-recognised cytokine storms, seen in children and adults with underlying rheumatological disorders. MAS requires prompt recognition and aggressive treatment as untreated the mortality rate is 8-22%.

This guideline focusses on MAS in the context of rheumatological disorders. If the child does not have a known underlying diagnosis, the differential diagnoses of primary or secondary HLH and MAS as part of the initial presentation of a rheumatological disorder should be considered.

Contents:

• Definition
• Urgent Investigations
• Published Diagnostic & Classification Criteria
• Initial Treatment
• Additional Considerations