Hemophagocytic Syndrome in Children and Adults

Abstract

Hemophagocytic syndrome, also known as hemophagocytic lymphohistiocytosis (HLH), is a heterogenic syndrome, which leads to an acute, life-threatening inflammatory reaction. HLH occurs both in children and adults, and can be triggered by various inherited as well as acquired factors. Depending on the etiology, HLH can be divided into genetic (i.e., primary) and acquired (i.e., secondary) forms. Among genetic HLH forms, one can distinguish between familial HLH and other genetically conditioned forms of HLH. Acquired HLH can be typically triggered by infections, autoimmune diseases, and malignancies. The most common symptoms of HLH are unremitting fever, splenomegaly, and peripheral blood cytopenia. Some severely ill patients present with central nervous system involvement. Laboratory tests reveal hyperferritinemia (often >10,000 μg/L), increased serum concentration of soluble receptor α for interleukin-2 (>2,400 U/L), hypertriglyceridemia, hypofibrinogenemia, coagulopathy, hyponatremia, hypoproteinemia, and elevated liver transaminases and bilirubin. Prognosis in HLH is very serious. Genetic HLH is always lethal if adequate therapy is not administered. Similarly, severe acquired cases often lead to death without appropriate treatment. Since HLH can be encountered by various specialists in the medical field, basic knowledge of this entity such as diagnostic criteria and treatment should be familiar to all physicians.

Management of the critically ill child with the sepsis/hemophagocytic lymphohistiocytosis/macrophage activation syndrome overlap syndrome

“…Overwhelming T-cell and macrophage activation results in the "cytokine storm" characterized by marked elevations of cytokine, such as interferon (IFN)-␥, tumor necrosis factor-␣, interleukin (IL)-6, IL-8, IL-10, IL-12, IL-18 and macrophage colony stimulating factor [27]. Gene expression studies on peripheral blood mononuclear cells in patients with active HLH have revealed downregulation of genes involved in innate and adaptive immune systems, including Toll-like receptor expression and B-cell and T-cell function [28,29]. Other mechanisms may involve single nucleotide polymorphism in genes important in the immune response and imbalance between infected cells and immune effector cells.…”

Toxic epidermal necrolysis and hemophagocytic lymphohistiocytosis: a case report and literature review

“…One fatality did occur, however [12], with a patient experiencing considerable comorbidities including chronic renal failure requiring hemodialysis. Considering that the overall pediatric mortality rate for TEN is below 30% [3], and for secondary HLH ranges between 8% and 22% [20], these reported outcomes are encouraging.…”

Fever-triggered Brugada syndrome in an adult patient presenting with hemophagocytic syndrome induced byChlamydophila pneumoniae

“…Hemophagocytic syndrome, also known as HLH, is a state of severe, life-threatening inflammation caused by an excessive, prolonged and ineffective immune response 9. Hemophagocytic syndrome has been classified according to the aetiology as either primary (ie, genetic) or acquired (ie, secondary to infections, malignancies or rheumatological disorders).…”