Akademik Veri Yönetim Sistemi
Turkiye Klinikleri Pediatri, cilt.20, sa.3, ss.241-250, 2011 (Scopus)
Hemophagocytic lymphohistiocytosis (HLH) is an invariably fatal disease, with familial (primary, FHLH) which may be syndromic or nonsyndromic and acquired (secondary, SHLH) forms. FHLH has an autosomal recessive inheritance, usually seen in infancy, commonly triggered by a viral infection. Various inherited immune deficiencies related with perforin/granzyme system of natural killer (NK) and CD8+ cytotoxic T-lymphocytes are found to be responsible. These defects maybe either in perforin synthesis or its dysregulated release due to abnormal vesicle transport, fusion with membrane and degranulation. SHLH has been associated with infections, malignancy and autoimmunity, secondary to a significant immune activation together with no known genetic mutations. Either forms of HLH is characterized by fever, cytopenia of two lines, hypertriglyceridemia and/or hypofibrinogenemia, hyperferritinemia, hemophagocytosis, elevated soluble interleukin-2 receptor (CD25), decreased CD8+ T or NK cell activity and splenomegaly. This common phenotype is also seen in patients with sepsis, systemic inflammatory response syndrome (SIRS), multiorgan dysfunction syndrome (MODS), and macrophage activation syndrome (MAS). However therapeutic options are radically different. Chemotherapy and bone marrow transplantation have been used for treatment of FHLH/SHLH whereas antibiotics and supportive treatment are used in severe sepsis/SIRS/MODS. MAS is treated with limited immunosupression. Clinical and laboratory similarities, but different prognosis and treatment of FHLH, SHLH versus sepsis/SIRS/MODS/MAS necessitates better understanding and identification of these processes. In this literature review we explored the cells, cytokines, biochemical characteristics and the proposed pathological mechanisms in HLH in order to understand how this common phenotype develops. Copyright © 2011 by Türkiye Klinikleri.