Hemophagocytic lymphohistiocytosis and macrophage activation syndrome: two rare sides of the same devastating coin

Abstract

Hemophagocytic lymphohistiocytosis (HLH) is a rare genetic hyperinflammatory syndrome that occurs early in life. Macrophage activation syndrome (MAS) usually refers to a secondary form of HLH associated with autoimmunity, although there are other causes of secondary HLH, such as infections and malignancy. In this article, we reviewed the concepts, epidemiology, clinical and laboratory features, diagnosis, differential diagnosis, prognosis, and treatment of HLH and MAS. We also reviewed the presence of MAS in the most common autoimmune diseases that affect children. Both are severe diseases that require prompt diagnosis and treatment to avoid morbidity and mortality.

Macrophage Activation Syndrome in Children: Update on Diagnosis and Treatment

“…MAS belongs to a group of disorders known as HLH. For educational purposes [9], HLH can be classified into two groups: primary (familial or genetic) and secondary (sporadic or acquired). Primary HLH is an autosomal-recessive genetic disorder that presents early in life, usually in infancy [10].…”