Acquired haemophagocytic lymphohistiocytosis (HLH) is a condition involving cytokine overproduction by defective cytotoxic T lymphocytes and natural killer cells, resulting in life-threatening cytopenias and multiorgan infiltration and dysfunction. Triggers for acquired HLH vary and include viruses, malignancies and autoimmune conditions. Recent reports suggest that HLH may be underdiagnosed ow...

Hemophagocytic Lymphohistiocytosis (HLH) is a clinical syndrome that develops due to the unregulated activation of the inflammatory system and is considered when a patient presents with a constellation of symptoms and objective findings consisting of fevers, splenomegaly, hepatomegaly, cytopenias, hepatitis, hypertriglyceridemia and/or hypofibrinogenemia, hyperferritinemia, biopsies of the bone...

Mutations in the perforin gene have been described in some patients with hemophagocytic lymphohistiocytosis (HLH), but the role of perforin defects in the pathogenesis of HLH remains unclear. Four-color flow cytometric analysis was used to establish normal patterns of perforin expression for control subjects of all ages, and patterns of perforin staining in cytotoxic lymphocytes (natural killer...

Hemophagocytic lymphohistiocytosis (HLH) has been described in patients with advanced stages of human immunodeficiency virus (HIV) infection, but rarely occurs during the seroconversion stage of acute HIV infection. We report a case of acute HIV syndrome that presented with virus-associated HLH. The patient recovered spontaneously without any immunomodulating therapy. This case suggests that ac...

Hemophagocytic lymphohistiocytosis (HLH) is one of the complications of Epstein-Barr virus (EBV) infection. Although the patients who have developed HLH following EBV have normal immune system, there are a few patients with EBV-induced immune deficiency who develop HLH as well. Here, we describe the case of a 10-year-old girl with neurological complications caused by EBV-induced HLH. The patien...

Hemophagocytic Lymphohistiocytosis (HLH) is a devastating disorder of uncontrolled immune activation characterized by clinical and laboratory evidence of extreme inflammation. This syndrome can be caused by genetic mutations affecting cytotoxic function (familial HLH) or secondary to infectious, rheumatologic, malignant, or metabolic conditions (acquired HLH). Prompt recognition is paramount an...

Two major transcriptional regulators of Caenorhabditis elegans bodywall muscle (BWM) differentiation, hlh-1 and unc-120, are expressed in muscle where they are known to bind and regulate several well-studied muscle-specific genes. Simultaneously mutating both factors profoundly inhibits formation of contractile BWM. These observations were consistent with a simple network model in which the mus...

 Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation, occurring as either a familial disorder or a sporadic condition, in association with a variety of triggers. This article will introduce a neonate with HLH in Iran. We report a case of HLH presenting with respiratory distress and fever, hepatosplenomegaly, jaundice and pancytopenia on the second day of life....

Hemophagocytic Lymphohistiocytosis (HLH) implies a benign generalized histiocytic proliferate with erythrophagocytosis and it includes familial hemophagocytic lymphohistiocytosis and secondary hemophgocytosis. Spinal fluid changes like mild to moderate pleocytosis (most of the cells are lymphocytes and macrophages) and sometimes hemophagocytosis are seen in primary HLH but are not reported in s...

Two unusual cases of hemophagocytic lymphohistiocytosis (HLH) complicating aplastic anemia (AA) are described. Each patient had a history of preexisting acute hepatitis of unknown cause at the time of HLH diagnosis and infection-associated secondary HLH. They developed high fever and pancytopenia. Hemophagocytes were seen in the bone marrow. With steroid (in combination with etoposide and CyA i...