Understanding organ dysfunction in hemophagocytic lymphohistiocytosis

Abstract

The comprehensive management of severe HLH requires the involvement of a multidisciplinary team in order to determine the best therapeutic strategy and to identify the underlying cause.

Hemophagocytic syndrome associated with cytomegalovirus infection in a severely immunocompromised AIDS patient: case report

“…EBV is the most common etiology, while CMV is associated with 30% to 40% of all virus-associated HLH cases [2]. This syndrome is a result of damage caused by cytotoxic activity of natural killer (NK) cells and T cells; thus the ineffective immune system is constantly stimulated to generate high levels of cytokines, such as tumor necrosis factor α (TNF-α) and interferon γ (IFN-γ), which stimulate the defense cells.…”

“…This syndrome is a result of damage caused by cytotoxic activity of natural killer (NK) cells and T cells; thus the ineffective immune system is constantly stimulated to generate high levels of cytokines, such as tumor necrosis factor α (TNF-α) and interferon γ (IFN-γ), which stimulate the defense cells. High levels of cytokines are responsible for the clinical picture [2,3]. HLH is an uncommon and frequently undiagnosed event, recently described in critically-ill patients [2][3][4]; it remains a diagnostic challenge, as the clinical presentation of this condition mimics sepsis, a frequent syndrome in ICU patients [5].…”

“…High levels of cytokines are responsible for the clinical picture [2,3]. HLH is an uncommon and frequently undiagnosed event, recently described in critically-ill patients [2][3][4]; it remains a diagnostic challenge, as the clinical presentation of this condition mimics sepsis, a frequent syndrome in ICU patients [5]. Laboratorial tests for diagnosis, such as serum triglyceride, ferritin and fibrinogen levels, are frequently not performed in the ICU, and they lack specificity, as they may be significantly altered as a result of critical illness.…”

Rare cause of fever in a patient with ulcerative colitis

“…1 First described by Scott and Robb-Smith in 1939, is characterized by a deficiency in cytolytic activity (impaired or absent function of NK cells and cytotoxic T cells), resulting in persistent activation of lymphocytes and histiocytes. This uncontrolled and inappropriate immune response leads to hypersecretion of proinflammatory cytokines and uncontrolled hemophagocytosis throughout the reticuloendothelial system.…”

“…HLH related to hematological malignancies or EBV infection carries a higher mortality rate than cases related to viruses or intracellular bacteria. 1,7,8 Treatment is based on control of the cytokine storm and cellular proliferation. Immunochemotherapy as proposed by the Study Group of the Histiocyte Society (first international protocol in 1994, updated in 2004) consists of combination therapy with etoposide, dexamethasone, and cyclosporine A, as well as, in selected patients with central nervous system involvement, intrathecal therapy with methotrexate and corticosteroids.…”