Haemophagocytic syndromes in adults: current concepts and challenges ahead

Haemophagocytic syndrome (HS), also referred to as haemophagocytic lymphohistiocytosis or macrophage activation syndrome, comprises a heterogeneous group of disorders featuring sepsislike characteristics typically combined with haemophagocytosis, hyperferritinemia, hypercytokinemia and variable cytopenias, often resulting in fatal multiple organ failure. The availability of widely accepted diagnostic and therapeutic guidelines for the hereditary, paediatric forms of HS has improved outcome and lead to a better pathophysiological understanding. Although similar, reactive (secondary) HS in adults are distinct from childhood forms. Limited awareness of this type of disorder and the absence of clinical guidelines are to blame for delayed diagnosis and dire prognosis in many cases of HS in adults. Moreover, the underlying mechanisms of adult HS remain to be unravelled yet. We summarise general features of HS and discuss particular characteristics of this disorder inadults. Furthermore, we describe a simple screening and diagnostic algorithm based on serum markers of macrophage activation (ferritin, soluble CD163 and soluble CD25) and morphological evidence of haemophagocytosis. Application of this strategy might be instrumental for recruiting patients for clinical studies, early diagnosis and hence improved prognosis. Indeed, there is evidence that a subgroup of patients with systemic inflammatory response syndrome presenting with signs of macrophage activation benefit from early administration of intravenous immunoglobulins. Clinical studies are needed to validate our diagnostic approach and to establish well defined prognostic and therapeutic algorithms. Finally, we will discuss whether similar processes contribute to HS in adults compared to childhood forms.

Hemophagocytosis exacerbated by G-CSF/GM-CSF treatment in a patient with myelodysplasia

We describe a 75-year-old man with neutropenia in whom bone marrow aspirate and biopsy demonstrated hemophagocytosis associated with myelodysplasia (MDS). Therapy with granulocyte-colony stimulating factor (G-CSF) and granulocyte-monocyte-colony stimulating factor (GM-CSF) caused splenomegaly and severe thrombocytopenia, which recurred upon rechallenge. We propose that myeloid growth factors may be detrimental in patients with MDS-associated hemophagocytosis.

A Case Report of the Effect of Plasma Exchange on Reactive Hemophagocytic Syndrome Associated with Toxic Shock Syndrome

We report here the case of a patient suffering from hemophagocytic syndrome (HPS) associated with toxic shock syndrome (TSS). A 50-year-old man was admitted because of fever, watery diarrhea and shortness of breath. Clinical analysis revealed systemic cyanosis, sunburn-like erythema and septic shock. Staphylococcus aureus was identified from both blood and sputum culture and the serum enterotoxin A antibody test was positive, suggesting that this was a case of TSS. Though the respiratory and hemodynamic status improved by the mechanical ventilation, fluid resuscitation with catecholamine and antibiotic therapy, the platelet count decreased rapidly. Bone marrow aspiration revealed a large quantity of hemophagocytosis by macrophages. This reactive HPS was treated not with immunosuppressive drugs but with therapeutic plasma exchange in order to prevent worsening of S. aureus infection. After plasma exchange, the circulating macrophage colony-stimulating factor (M-CSF) level was reduced and the platelet count increased rapidly. Bacteria associated HPS remains a difficult diagnosis with high mortality and there is a crucial question of whether this should be treated with immunosuppressive drugs. The patient's clinical course would suggest that the therapeutic plasma exchange should be considered as a therapeutic tool for the bacteria associated HPS instead of immunosuppressive drugs.

Syndrome d’activation macrophagique réactionnel : une cause sous-estimée de défaillance multiviscérale en réanimation ?

The incidence of the haemophagocytic syndrome in the ICU patients with multiple organ failure seems to be high. The haemophagocytic syndrome can be considered as the consequence of the initial aggression leading to multiple organ failure. On the contrary the haemophagocytic syndrome could be the cause of multiple organ failure. A case of haemophagocytic syndrome is presented which led to rapidly fatal multiple organ failure.

Sickle cell crisis associated with hemophagocytic lymphohistiocytosis

Sickle-beta(+) (beta(+)) thalassemia is a double heterozygous genetic disorder characterized by both a qualitative and quantitative abnormality. We present a case of an African American male who was first diagnosed with sickle cell disease (SCD) at the age 23 years when he presented with generalized bone pain, fever, and hepatosplenomegaly. Laboratory findings included thrombocytopenia, microcytic anemia, and markedly elevated ferritin. He was subsequently diagnosed with a sickle-beta thalassemia hemoglobinopathy. Findings in the bone marrow aspirate and biopsy were consistent with hemophagocytic lymphohistiocytosis (HLH). HLH resolved with the resolution of sickle cell bone pain crisis without use of immunosuppressive therapy. To the best of our knowledge this is the first documented case of HLH associated with sickle cell bone pain crisis.

Increased IL-16 levels in hemophagocytic lymphohistiocytosis

Serum levels of interleukin-16 (IL-16) were measured to investigate its role in the pathophysiology of hemophagocytic lymphohistiocytosis (HLH). Serum IL-16 levels in patients with acute HLH were significantly higher than those in healthy controls and patients with infectious mononucleosis. They returned to normal levels in the convalescent phase of the disease. In contrast to serum interferon-gamma (IFN-gamma) levels, serum IL-16 levels showed a gradual decrease over the course of the disease. Serum IL-16 levels showed a significant positive correlation with serum levels of soluble IL-2 receptor, IFN-gamma, and interleukin-18, body temperature, and serum lactic dehydrogenase (LDH) levels. An increase in IL-16 mRNA expression was detected in the liver of an HLH patient. These results suggest that IL-16 plays an important role in the pathophysiology of HLH by TH1 cell recruitment and activation at organs with inflammation.

Hemophagocytic syndrome associated with antiepileptic drug

An 8-year-3-month-old male with right porencephaly and epilepsy was found to have skin rash 2 weeks after the beginning of treatment with lamotrigine. One month later he suffered from impaired liver function and pancytopenia in the presence of hypocellular bone marrow with hemophagocytosis. No evidence of infection was evident. Intravenous immunoglobulin and steroid were administered with discontinuation of lamotrigine; the hemogram and liver function profile improved dramatically. Hemophagocytic syndrome should be considered a possible cause of pancytopenia in patients taking new antiepileptic drugs such as lamotrigine.

Immunosuppressive therapy with antithymocyte globulin and cyclosporine for prolonged marrow failure after hemophagocytic syndrome

We describe a patient with typical hemophagocytic syndrome (HPS) in whom pancytopenia was refractory to steroid pulse therapy. He was successfully treated with immunosuppressive therapy using antithymocyte globulin (ATG) and cyclosporine (CyA), which is known to be effective for aplastic anemia (AA). Activation of histiocytes occurs in HPS as a response to several cytokines produced by activated T lymphocytes, while apoptosis of hematopoietic stem cells in AA is caused by T lymphocyte-derived cytokines. The response of this patient indicated that both diseases may have some similar immune-mediated conditions involving the activation of T lymphocytes and that intensive immunosuppressive therapy with ATG and CyA might be a useful strategy for steroid-resistant HPS.

Latency pattern of Epstein-Barr virus and methylation status in Epstein-Barr virus-associated hemophagocytic syndrome

Expression of different panels of latent gene transcripts is controlled by usage of three distinct Epstein-Barr virus (EBV) nuclear antigen (EBNA) promoters (Wp, Cp, and Qp). EBV-associated hemophagocytic syndrome, which is often a fatal disease and generally occurs after primary EBV infection, is characterized by monoclonal or oligoclonal proliferation of EBV-infected T cells. The latency pattern and EBNA promoter (Wp, Cp, and Qp) usage in EBV-infected cells from three patients with EBV-associated hemophagocytic syndrome were examined by reverse transcription-polymerase chain reaction (PCR). Three samples from the patients expressed EBER, EBNA1, EBNA2, latent membrane protein (LMP)1, and LMP2A transcripts. The transcripts of EBNA1 were initiated from not only Wp/Cp but also Qp. Lytic cycle Fp-initiated EBNA1 and EBV lytic gene BZLF1 transcripts were not detected. The methylation statuses of three EBNA promoters in three patients with EBV-associated hemophagocytic syndrome and in two patients with infectious mononucleosis were also analyzed using bisulfite PCR analysis. Wp was hypermethylated, and Qp was unmethylated in both diseases. Cp was highly methylated in EBV-associated hemophagocytic syndrome, however, whereas Cp was almost unmethylated in infectious mononucleosis. These results suggest that there may be distinct EBV-infected cell populations in EBV-associated hemophagocytic syndrome, which exhibit different patterns of EBV latent gene expression. The methylation status in Cp and phenotype of EBV-infected cells may be critical differences in EBV-associated hemophagocytic syndrome and infectious mononucleosis.

[Excessive hyperferritinemia as an indication of a reactive hemophagocytosis syndrome]

HISTORY AND ADMISSION FINDINGS

A 17-year-old girl with a history of a polyarthritis of unknown etiology was admitted because of acute fever and general weakness. There were palpable cervical lymph nodes and her body temperature was 39.5 degrees C.

INVESTIGATIONS

GOT was raised to 282 U/1, GPT to 266 U/l lactate dehydrogenase to 1275 U/I and bilirubin to 0.6 mg/dl. The Quick value was 67%, albumin 28 mg/dl. White cell count was decreased to 1700/microl, with 43% granulocytes, 39% lymphocytes, 17% monocytes. Platelet count was 64,000/microl. Ultrasound revealed splenomegaly. Ferritin was markedly raised to 11,860 ng/ml (normal up to 150 ng/ml). An epstein-barr-virus infection was found.

THERAPY AND CLINICAL COURSE

Suspecting a reactive hemophagocytosis syndrome, she was treated with prednisolone (2 mg/kg). The diagnosis was confirmed by a bone marrow aspirate. The patient's condition and laboratory values improved rapidly.

CONCLUSION

Markedly increased ferritin levels in a clinically septic patient with an underlying rheumatic disease indicates a hemophagocytotic syndrome. High dosage steroid should be started before there is biopsy confirmation of the disease.

[Clinical analysis of 13 patients with hemophagocytic syndrome]

OBJECTIVE

To investigate the clinical features and prognosis of hemophagocytic syndrome (HS).

METHODS

The clinical symptoms, signs, and laboratory-test data in 13 patients with HS were analysed.

RESULTS

Increase in lactate dehydrogenase (LDH) and hyponatremia was found in all of the patients. Prolonged prothrombin time, hypofibrinogenemia, hyertriglyceridemia, and hyperferricemia also existed in some cases. The mature hemophagocytic histocyte and hemophagocytic phenomenon were observed with Whrigt-Geimsa and immunocytochemical staining. One (16.6%, 1/6) patient with infectious associated HS (IAHS) and 4 (80%, 4/5) with non-IAHS died of infection and primary disease.

CONCLUSION

HS especially non-IAHS is an extremely dangerous state with high mortality. Obstinate hyponatremia may be a characteristic of HS in the early stage. It's important to supervise the change of hemophagocyte in peripheral blood and bone marrow of HS. Immunocytochemical studies on smear of enriched peripheral white blood cells are helpful to identify the primary pathogenesis of the benign or malignant diseases.

The serum cytokine profiles of lymphoma-associated hemophagocytic syndrome: a comparative analysis of B-cell and T-cell/natural killer cell lymphomas

To elucidate the differences in pathogenesis between lymphoma-associated hemophagocytic syndromes (LAHS) of the T-cell/ natural killer cell (T/NK) and B-cell (B) types, we comparatively analyzed the clinical features and serum cytokine profiles of 33 patients with LAHS registered in the Kyoto University Hematology/Oncology Study Group. The serum cytokine levels of each patient group (B-LAHS versus T/NK-LAHS) were expressed as the ratio of the median to the upper normal values of the respective cytokines and were as follows: 19.05 versus 13.99 for soluble interleukin 2 (IL-2) receptor, 0.67 versus 0.67 for granulocyte-macrophage colony-stimulating factor (GM-CSF), 0.64 versus 1.26 for G-CSF, 5.70 versus 3.61 for M-CSF, 1.54 versus 3.39 for interferon gamma (IFN-gamma), 13.17 versus 1.17 for IL-6, 6.88 versus 1.58 for tumor necrosis factor alpha (TNF-alpha), 0.71 versus 0.41 for IL-1beta, 1.99 versus 0.21 for IL-12, and 105.32 versus 29.65 for IL-10. The serum levels of IL-6, TNF-alpha, and IL-10 were significantly higher in the B-LAHS group, whereas those of IFN-y were significantly lower. These differences between the 2 groups may reflect a difference in the pathogenesis Higher serum levels of IL-6, TNF-alpha, and IL-10 may be derived at least partly from neoplastic B-cells themselves In addition, the extremely high serum levels of IL-10 suggest that a compensatory anti-inflammatory process may operate in both groups and give rise to a profound immunosuppressive state and a poor outcome.

Findings in familial haemophagocytic lymphohistiocytosis prior to symptomatic presentation

Familial haemophagocytic lymphohistiocytosis (FHL) is a rare, autosomal recessive disease of infancy and early childhood clinically characterized by fever, hepatosplenomegaly, lymphadenopathy, rash, neurological symptoms and icterus. Common laboratory findings include cytopenia, elevated liver enzymes, hyperbiliriubinaemia, hypofibrinogenaemia and hypertriglyceridaemia. The natural killer cell function is frequently decreased or absent. A diffuse lymphohistiocytic infiltration is seen in the reticuloendothelial system, often with haemophagocytosis. Molecular diagnosis is available in a minority of FHL families. Without adequate treatment and bone-marrow transplantation, the disease is fatal. A 6-wk-old child with FHL is presented. Shortly before the clinical onset of the disease, blood testing and bone-marrow examination had been carried out. All results were considered normal at that time.

CONCLUSION

Blood tests and bone-marrow examination may be normal shortly before the clinical presentation and therefore do not exclude the diagnosis of FHL. There is a need for extended molecular diagnostic possibilities.

Hemophagocytic lymphohistiocytosis is associated with deficiencies of cellular cytolysis but normal expression of transcripts relevant to killer-cell-induced apoptosis

In 65 patients with hemophagocytic lymphohistiocytosis (HLH), we found an as yet undescribed heterogeneity of defects in cellular cytotoxicity when assay conditions were modified by the incubation time, the presence of mitogen, or interleukin-2 (IL-2). The standard 4-hour natural killer (NK) test against K562 targets was negative in all patients. In patients deficient in type 1 (n = 21), type 2 (n = 5), and type 4 (n = 8) HLH, negative NK function could be reconstituted by mitogen, by IL-2, or by prolongation of the incubation time (16 hours), respectively. Most patients (n = 31) displayed the type 3 defect, defined by a lack of any cellular cytotoxicity independent of assay variations. The characteristic hypercytokinemia also concerned counterregulatory cytokines, such as proinflammatory interferon-gamma (IFN-gamma), simultaneously elevated with suppressive IL-10 in 38% of types 1-, 2-, and 4-deficient patients and in 71% of type 3-deficient patients. Elevated IFN-gamma alone correlated with high liver enzymes, but sCD95-ligand and sCD25 did not-though these markers were expected to indicate the extent of histiocytic organ infiltration. Outcome analysis revealed more deaths in patients with type 3 deficiency (P =.017). Molecular defects were associated with homozygously mutated perforin only in 4 patients, but other type 3 patients expressed normal transcripts of effector molecules for target-cell apoptosis, including perforin and granzyme family members, as demonstrated by RNase protection analysis. Thus, target-cell recognition or differentiation defects are likely to explain this severe phenotype in HLH. Hyperactive phagocytes combined with NK defects may imply defects on the level of the antigen-presenting cell.

[Systemic lupus erythematosus with bilateral salivary gland swelling and clouding of consciousness accompanied by hemophagocytic syndrome--a study of serial determination of serum cytokines]

We investigated changes in various serum cytokines in a case of systemic lupus erythematosus (SLE) accompanied by hemophagocytic syndrome (HPS). The patient, a 15-year-old male, presented in December 1998 with bilateral salivary gland swelling and a history of fever continuing for more than 10 days. After admission, cerebellar ataxia and clouding of consciousness developed. Laboratory examinations revealed leukopenia, thrombocytopenia, high serum LDH and ferritin, hypercytokinemia, and prominent hemophagocytosis in the bone marrow. Given these findings and positive titers of antinuclear antibody, hypocomplementemia, proteinuria and pericarditis, a diagnosis of HPS with associated SLE was made. The patient was treated with high dose methylprednisolone followed by oral prednisolone and cyclosporine. The patient's clinical symptoms, abnormal blood and urine laboratory data consequently improved, and no recurrence of the symptoms has been documented. However, hemophagocytosis in bone marrow recurred with concomitantly increased serum levels of IL-6 and IL-1 beta. This case indicated that aberrant production of these inflammatory cytokines might be involved in HPS in autoimmune disease.

Epstein-Barr virus-associated T-lymphoproliferative disease with hemophagocytic syndrome, followed by fatal intestinal B lymphoma in a young adult female with WHIM syndrome. Warts, hypogammaglobulinemia, infections, and myelokathexis

A rare association of Epstein-Barr virus-associated T- and B-lymphoproliferative disease (EBV(+) T- and EBV(+) B-LPD) in a patient with WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome is reported. A 26-year-old Japanese female, who had been treated for WHIM syndrome since early childhood, developed hemophagocytic syndrome associated with EBV(+) T-LPD at the lymph nodes and spleen. The disease rapidly resolved in response to prednisolone therapy. However, 6 weeks later, fatal EBV(+) B lymphoma unresponsive to chemotherapy occurred in the intestine and other organs. Caution must be exercised that the patient with WHIM syndrome may be at risk for EBV-LPD.

Reactive macrophage activation syndrome: a simple screening strategy and its potential in early treatment initiation

QUESTIONS UNDER STUDY

starting treatment of reactive macrophage activation syndromes as early as possible (rMAS, haemophagocytic lymphohistiocytosis), e.g., with intravenous immunoglobulins (IVIG), seems to be essential for optimal outcome. However, there is no diagnostic gold standard which reliably indicates need for early treatment. We used a simple screening strategy consisting of serum ferritin measurements and/or morphological assessment of haemophagocytosis and compared the studied patient population with published series.

METHODS

Retrospective analysis of clinical and laboratory data of 57 patients experiencing 60 episodes of rMAS.

RESULTS

Screening by serum ferritin measurements and/or morphological assessment of haemophagocytosis of patients presenting with a systemic inflammatory response syndrome (SIRS) indicates that rMAS might be considerably more frequent than stated in the literature. Serum ferritin exceeded >10,000 microg/L in 91% rMAS episodes. Although the patient population studied was otherwise similar in most aspects to the published rMAS series, the fact that 40% of patients fulfilled the criteria for Still's disease (SD) as the disorder underlying rMAS is remarkable and questions the distinct nature of the two diseases. IVIG responders and non-responders did not differ regarding their initial characteristics with exception to the timepoint of IVIG administration, confirming the importance of early treatment initiation. Malignancy-associated rMAS however, has a poor prognosis and seems to be refractory to manipulation with IVIG in most instances, even when responding initially.

CONCLUSIONS

rMAS has to be considered in patients with a SIRS- or SD-like clinical presentation. Hyperferritinaemia >or=10,000 microg/l seems to be a good marker for defining patients with or at risk for developing rMAS and should be completed with a morphological assessment of haemophagocytosis. The perception of acute SD and rMAS as two distinct entities has to be questioned at least in a subgroup of patients.

Hemorrhagic fever with renal syndrome presenting with hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis--which is associated with a variety of infections, malignant neoplasms, autoimmune diseases, and immunodeficiencies--is an uncommon syndrome with a rapidly fatal outcome. We describe the first case of hemorrhagic fever with renal syndrome due to Hantaan virus presenting with reactive hemophagocytosis.

Clinical and biological significance of clonal macrophage detection in hemophagocytic syndrome

By using the method of clonal analysis the evidence to prove that Hemophagocytic syndrome (HPS) is reactive or malignant was investigated to probe into the pathogenesis of HPS and its relations with clinical prognosis. The macrophages abnormally proliferated in bone marrow were isolated. Electrophoresis analysis was made after DNA extraction, enzyme restriction of human ardrogen receptor (HUMARA) genetic locus, and PCR amplification. In the 9 specimens, clonal proliferation was found in 2 cases and nonclonal proliferation in 7. Among the 7 cases of nonclonal proliferation, 3 were voluntarily discharged without clinical outcome, 2 cases fully recovered after 2-3 week treatment of large dose gamma globulin intravenous drip and hormone therapy, 1 case died at the 43th day after the hormone and anti-infection therapy, and one case was found to have granular leukoblast in peripheral blood after 3 weeks and diagnosed as having M2a after bone puncture. For the two patients with clonal proliferation, one obtained remission after chemotherapy and the other was died after 32 days without chemotherapy. It was concluded that there do exist clonal or malignant proliferation in HPS, so not every case is reactive.

Serum levels of interleukin 15 in patients with rheumatic diseases

OBJECTIVE

The role of the cytokine interleukin 15 (IL-15) in rheumatic disease is unclear. We examined serum levels of IL-15 in patients with various rheumatic diseases.

METHODS

Serum levels of IL-15 were determined by sandwich ELISA.

RESULTS

Serum levels of IL-15 were significantly increased in patients with polymyositis/dermatomyositis, polyarteritis nodosa, and systemic sclerosis; and significantly increased as well in disease complicated by interstitial pneumonitis (IP), hemophagocytic syndrome (HPS), and/or vasculitis. Patients with serum IL-15 levels < or = 5 pg/ml showed significantly high rates of survival.

CONCLUSION

IL-15 is related to the pathogenesis of IP, HPS, and/or vasculitis. Serum IL-15 level could possibly be used as a marker of prognosis.

Serous fluid cytology as a means of detecting hemophagocytosis in Epstein-Barr virus-induced autoimmune hemolytic anemia

The case of a 22-yr-old male who after a brief febrile episode developed autoimmune hemolytic anemia and right pulmonary infiltrate with pleural effusion is presented. Cytologic examination of the pleural fluid revealed lymphocytosis and hemophagocytosis, primarily of red blood cells (RBCs) by mature histiocytes. There was accompanying splenomegaly, laboratory evidence of hepatic dysfunction, and retroperitoneal lymphadenopathy. Besides profound reduction of red blood cells in the peripheral blood, there was reduction of lymphocytes and platelets. As a neoplastic process was ruled out by bone marrow and pleural biopsies, the disease was considered to be virus-induced and was halted and progressively regressed with early institution of vigorous antiinflammatory therapy with adrenocortical steroids. Upon reviewing the case, examination of the bone marrow biopsy disclosed limited hemophagocytosis of RBCs and lymphocytes by histiocytes and considerable viral cytopathic effect on hematopoietic cells (red and white cell precursors and megakaryocytes), which by appropriate immunolabelling was identified as induced by Epstein-Barr virus. A virus-related acquired hemophagocytic syndrome in its early stages was probably present, yet an undesirable clinical outcome was averted by early institution of vigorous steroid therapy. The need to recognize early hemophagocytic changes in cytologic specimens for early institution of appropriate therapy is emphasized. The possibility of erythrophagocytosis, also manifested during the course of an autoimmune hemolytic process and unrelated to hemophagocytic syndrome, is discussed.

Familial hemophagocytic lymphohistiocytosis: too little cell death can seriously damage your health

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare and fatal disease of early childhood characterized by a non-malignant accumulation of activated T lymphocytes and histiocytes in the reticuloendothelial system. Moreover, immune system derangement, with prominent hypercytokinemia and low or absent cytotoxic T and natural killer (NK) cell activity, is a consistent feature of this autosomal recessive disorder. Recent work has demonstrated that the degree of spontaneous caspase activation in FHL lymphocytes is attenuated in vitro whereas Fas-mediated caspase activation and apoptosis induction remains unmitigated, and FHL can thus be distinguished from the related chronic disorder of immune regulation termed autoimmune lymphoproliferative syndrome or ALPS. However, subsequent studies have identified mutations in the gene encoding perforin, a cytotoxic granule constituent required for apoptotic killing of target cells, in a number of FHL patients. Hence, the underlying defect in FHL may be conceived of as a lack of apoptosis triggering within the immune system, rather than apoptosis resistance per se. These observations represent an important step in our understanding of the pathogenesis of FHL and also serve to emphasize the pivotal role of cellular (perforin-based) cytotoxicity in the regulation of immune homeostasis.

Interleukin-18 in hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is characterized by dysregulated hyperactivation of macrophages and T helper 1 (Th1) cells accompanied by excessive secretion of inflammatory cytokines. Although TNF-alpha and IFN-gamma are known to be important factors for the development of the disease, the mechanism of their overproduction has not been clarified, yet. We measured serum IL-18 levels of patients with HLH to investigate the possible significance of IL-18 in its pathophysiology, especially in IFN-gamma production. IL-18 levels were significantly increased in all patients with HLH compared with healthy controls. A significant correlation was observed between IL-18 and IFN-gamma levels. In addition to IFN-gamma and soluble Fas ligand (sFasL), IL-18 levels significantly correlated with disease activity. IL-18 may play important roles in the pathogenesis of HLH, particularly through induction of Th1 cells. In addition, IL-18 measurement may not only be useful for the diagnosis, but also for the evaluation of disease activity.

[Hemophagocytic syndrome with hemophagocytes in the peripheral blood]

A 79-year-old man developed a high fever, facial erythema, anemia and thrombocytopenia during conservative therapy for ischemic colitis. Peripheral hemophagocytes (PHP) were identified in smear specimens of peripheral blood, and hemophagocytes also showed proliferation in the bone marrow. After treatment with steroid and antibiotics under a diagnosis of bacteria-associated hemophagocytic syndrome, the patient recovered rapidly. Although the prognosis of hemophagocytic syndrome (HPS) depends on the underlying disease, any delay in diagnosis can sometimes result in a poor outcome in cases of infection-associated hemophagocytic syndrome. In the present case, early diagnosis of bacteria-associated hemophagocytic syndrome was made by detection of PHP. The appearance of PHP in virus-associated hemophagocytic syndrome (VAHS) and after administration of macrophage colony stimulating factor has been described. However, the significance and cytological characteristics of PHP have been unknown. In this report, we propose that PHP can be a useful indicator for early diagnosis of HPS, and we report 7 additional cases in which the PHP was detected retrospectively. The cytological characteristics and biological significance of PHP are discussed.

Progressive nodular histiocytosis accompanied by systemic disorders

Progressive nodular histiocytosis is a proliferative process of histiocytes, the main element of which is the dermal dendrocyte. It is considered to form part of a group of histiocytic disorders related to juvenile xanthogranuloma, which also includes xanthoma disseminatum, benign cephalic histiocytosis, spindle cell xanthogranuloma and generalized eruptive histiocytosis; disorders which perhaps represent the spectrum of one single entity. We present the case of a 57-year-old man who, for 26 years, had had a progressively deforming process of cutaneous lesions, with systemic involvement, including chronic myeloid leukaemia, hepatosplenomegaly, hypothyroidism, hyperuricaemia and hypocholesterolaemia. We have not been able to establish precisely the relationship between these features.

High levels of IL-10 and determination of other cytokines and chemokines in HIV-associated haemophagocytic syndrome

Haemophagocytic syndrome (HPS) and HIV infection are both associated with cytokine network dysregulation. We therefore analysed plasma levels and mRNA synthesis in peripheral blood mononuclear cells (PBMC) of cytokines, chemokines and chemokine receptors in one HIV-infected patient with HPS. We compared the results with those for eight HIV-infected patients with similar CD4+ T cell counts (207/mm3 versus controls: median 214/mm3) and plasma virus load (4.1 log copies/ml, versus controls: median 4.2 log copies/ml). The HPS patient had a lower viral DNA load in PBMC and higher plasma levels of interferon-gamma, IL-10, and macrophage inflammatory protein (MIP)-1beta. No difference in plasma tumour necrosis factor-alpha (TNF-alpha), IL-6 and MIP-1alpha concentration was observed between the HPS patient and control patients. No difference was observed in TNF-alpha, IL-1beta, IL-10, IL-4, MIP-1alpha, MIP-1beta, RANTES, CXCR-4, and CCR-5 mRNA levels in PBMC, but IL-6 levels were higher in the HPS patient. Our results emphasize the role of IL-10 in the control of immune hyperactivation that is observed in HPS.

Neuron-specific enolase in hemophagocytic lymphohistiocytosis: a potential indicator for macrophage activation?

To determine the pathogenesis of hemophagocytic lymphohistiocytosis (HLH), serum levels of neuron-specific enolase (NSE) and cytokine profiles were investigated. Serum concentrations of NSE and several cytokines were measured by immunoassays, and the association was evaluated in 18 HLH patients. Serum NSE levels increased (> 10 ng/mL) in 27/29 samples (93%) during the active febrile phase, the mean level of which (35.9 ng/mL) was much higher than that during the remission phase (11.2 ng/mL) (P = .001). The peak levels of NSE in 11 patients who required cytotoxic agents were higher than those in 7 patients without chemotherapy, 64.6 +/- 49.4 and 17.9 +/- 12.9, respectively (P = .265). The NSE levels correlated positively with the levels of interferon (IFN)-gamma (Pearson's correlation coefficient [r] = 0.408, P = .044), soluble interleukin-2 receptor (sIL-2R) (r = 0.464, P = .048), lactate dehydrogenase (r = 0.830, P < .00001), aspartate aminotransferase (r = 0.531, P = .003), and ferritin (r = 0.715, P < .00001), and correlated negatively with platelet count (r = -0.422, P = .021), but not with other parameters, including tumor necrosis factor-alpha, IL-1 beta, IL-18, soluble Fas ligand and C-reactive protein. Multiple regression analysis indicated that the correlation of NSE with platelet count was independent of other correlations. Sequential NSE changes well reflected the clinical course of patients. Immunohistochemical staining revealed an appreciable number of NSE-positive histiocytes in bone marrow specimens with florid hemophagocytosis. These results suggest that the circulating NSE originated from macrophages stimulated with IFN-gamma/sIL-2R, and partly from the destruction of platelets. Serum NSE level may be a useful marker for predicting the disease progression of HLH.

Elevation of soluble Fas and soluble Fas ligand in reactive macrophage activation syndromes

Derailed T-cell activation can give rise to life-threatening macrophage activation, the final common pathway of the different forms of reactive macrophage activation syndromes (rMAS). Besides inappropriate activation of the immune system, impaired termination of immune responses might be another mechanism leading to rMAS. The Fas (CD95)/Fas ligand (CD95 ligand) system functions in turning off immune responses by executing activation-induced cell death (AICD). Soluble Fas (sFas) and Fas ligand (sFasL) can interfere with their corresponding membrane-bound counterparts, qualifying them as potential parameters of impaired immune termination. Hence, sFas and sFasL were analyzed in sera of rMAS patients. We show that soluble Fas/CD95 (sFas) is elevated >2 SD over the mean of controls in all 8 rMAS episodes studied (mean 12.08 +/- 6.12 ng/mL, range 3.7-20.2; controls 2.46 +/- 0.49, range 1.5-2.9). sFasL was detected during five rMAS episodes (0.70 +/- 0.49 ng/mL, range 0.16-1.28; controls all below the limit of detection of 0.1). In addition, both parameters decrease during convalescence, reflecting clinical evolution. In conclusion, sFas seems to be consistently elevated during acute rMAS. sFasL is detected only in a subgroup of our adult rMAS patients extending the recent finding of sFasL elevation in a majority of children with macrophage activation syndromes (Hasegawa et al. Blood 1998;91(8):2793-2799). By interfering with AICD, sFas and sFasL might contribute to the pathogenesis of at least a subset of rMAS.

Platelet-activating factor acetylhydrolase and haemophagocytosis in the sepsis syndrome

Sepsis syndrome (SS) is associated with depressed PAF acetylhydrolase, the enzyme responsible for the degradation of platelet activating factor. PAF acetylhydrolase is in a large part produced by macrophages, whose inadequate activation with haemophagocytosis is frequent in patients with SS. The aim of this study was to test the hypothesis that PAF acetylhydrolase levels could be affected in these critically ill patients, because of the large amounts produced by activated macrophages in vitro and in vivo in animal models. The levels of serum PAF acetylhydrolase were assessed in 90 SS patients, who were divided into three groups: patients with (n = 34) or without haemophagocytosis (n = 31), and patients without thrombocytopenia (n = 25) who were used as a control group. The number of organ dysfunctions was matched between patients with haemophagocytosis and controls. Normal reference values were obtained in 59 randomly selected blood donors. Circulating levels of PAF acetylhydrolase were significantly (p = 0.0001) decreased in patients with SS (57+/-3 nmol/ml/min, n = 90) when compared with healthy subjects (69+/-3 nmol/ml/min, n = 59). PAF acetylhydrolase levels were greater in the presence of a haemophagocytosis but without statistical significance (64.2+/-6.5 vs. 50.1+/-2.8:p = 0.25). Despite the fact that macrophagic activation stimulates the in vitro release of PAF acetylhydrolase, no difference was found between patients with or without haemophagocytosis. The mechanism and the role of the PAF acetylhydrolase reduction in SS patients remain to be determined.

Fatal virus-associated hemophagocytic syndrome associated with coexistent chronic active hepatitis B and acute hepatitis C virus infection

A 28-year-old man was admitted to our department with intermittent fever, hepatosplenomegaly and pancytopenia. Liver parameters and serum ferritin were markedly elevated. Bone marrow biopsy showed hypocellularity, histiocytic hyperplasia, and hemophagocytosis consistent with a virus-associated hemophagocytic syndrome (VAHS). There was serological evidence of chronic active hepatitis B and acute hepatitis C virus infection. The patient died despite aggressive immunosuppressive and supportive treatment. Autopsy revealed signs of acute viral hepatitis with cholestasis. Histiocytes engaged in hemophagocytosis were observed in bone marrow and spleen. The condition was interpreted as VAHS associated with chronic active hepatitis B and acute hepatitis C virus infection. To our knowledge this is the first report of a hemophagocytic syndrome in that setting.

Serum ferritin and lactate dehydrogenase in a case of hemophagocytic lymphohistiocytosis

A 40-day-old baby girl presented with intermittent fever, lymphadenopathy, massive hepatosplenomegaly, progressive pancytopenia and features of disseminated intravascular coagulopathy. A bone marrow aspiration was performed and showed florid histiocytic proliferation with marked hemophagocytosis. Based on the diagnostic guideline for Hemophagocytic Lymphohistiocytosis proposed by the Familial Hemophagocytic Lymphohistiocytosis Study Group of Histiocyte Society, this patient has fulfilled most of the criteria. We have also found that serum ferritin and lactate dehydrogenase to be very high in this patient. It remains uncertain whether the disorder is reactive or neoplastic.

Biomarker and morphological characteristics of Epstein-Barr virus-related hemophagocytic lymphohistiocytosis

BACKGROUND

Viruses may induce primary as well as secondary hemophagocytic lymphohistiocytosis (HLH), but it may not be possible to discriminate between these two in patients with a negative family history. Among these HLH cases, fulminant and fatal virus-associated hemophagocytic syndrome (VAHS) occurs mostly in relation to Epstein-Barr virus (EBV) infection. Although the immunological characteristics of EB-VAHS were previously reported, data on non-EB-VAHS were sporadic and fragmentary. This study has compared the clearly distinguishable groups of EBV-positive vs. EBV-negative HLH cases.

PROCEDURE

Among 26 patients with EBV-related HLH and 12 patients with non-EBV HLH, peripheral blood mononuclear cell (PBMC) subsets and serum concentrations of cytokines at the active phase of the disease were compared. Blood and bone marrow smears were also compared.

RESULTS AND CONCLUSIONS

The frequency of the CD3+HLADR+ subset in PBMC (median 34.3% vs. 4.8%), of serum concentrations of interferon (IFN)-gamma (median 105 U/ml vs. 2.4 U/ml), and of soluble interleukin-2-receptor (sIL-2R) (median 14,700 U/ml vs. 3,412 U/ml) were significantly different between these two groups. Morphological characteristics were noted for EBV-related HLH cases. Mortality also differed between these two groups, 9/26 vs. 0/12 (P = 0.05). Data indicate pronounced immunological imbalance and poor prognosis in EBV-related HLH cases. These parameters could be useful for determining an EBV involvement as well as risk factors in the early care and treatment of HLH patients.

Elevation of the serum Fas ligand in patients with hemophagocytic syndrome and Diamond-Blackfan anemia

Fas ligand (FasL) is a membrane protein that is expressed in activated T cells and natural killer cells. FasL binds to Fas on target cells and induces apoptosis. There exists a soluble form of FasL (sFasL), and sFasL also induces apoptosis of Fas-bearing cells. The serum sFasL concentrations were reported to be elevated in patients with large granular lymphocytic leukemia and natural killer cell lymphoma. In this study, we have measured serum sFasL concentrations in other hematological disorders, including severe aplastic anemia (SAA), hemophagocytic lymphohistiocytosis (HLH), and Diamond-Blackfan anemia (DBA). The serum sFasL concentration of age-matched healthy controls was 0.16 +/- 0.11 ng/mL (mean +/- SD, n = 22). The serum sFasL levels in the patients with HLH and DBA were 3.75 +/- 3.82 (n = 19; P < .0001, HLH v control) and 2.76 +/- 2.43 ng/mL (n = 6; P = .012, DBA v control), respectively. Serum interferon-gamma concentration was elevated in the patients with HLH (1.61 +/- 2.62 ng/mL) but not in those with DBA (below the detectable level). These results suggest that the Fas-FasL system plays a role, at least in part, in the pathophysiology of HLH and DBA.

Reduced Tyk2/SHP-1 interaction and lack of SHP-1 mutation in a kindred of familial hemophagocytic lymphohistiocytosis

Familial hemophagocytic lymphohistiocytosis (FHLH) is an autosomal recessive disease with features similar to those of the murine motheaten phenotype resulting from mutations of protein tyrosine phosphatase SHP-1. This has raised the possibility that defects in SHP-1 or SHP-1-regulated signaling molecules may be present in FHLH. In this study, we examined SHP-1 protein and transcript in the peripheral blood mononuclear cells (PBMC) of an FHLH family. Our results show that the FHLH patient and the parents express comparable levels of a single SHP-1 protein and that the SHP-1 cDNA clone from the patient contains no mutation in the coding region. Interestingly, a reduced association of SHP-1 with the Jak family kinase Tyk2 was detected in the patient and the defect appears to have been inherited from one of the parents. This reduced SHP-1/Tyk2 association is likely due to a defect in Tyk2 or in cellular factors regulating Tyk2, because we found no abnormalities in SHP-1 or in SHP-1 association with the other Jak kinases. These data demonstrate that the SHP-1 gene is intact in FHLH and that the defect in some cases with this disease may involve signaling molecules regulated by SHP-1.

Hemophagocytic syndrome and T-cell lymphoma after kidney transplantation: a case report

Lymphoma in immunocompromised transplant patients is a feared cause of morbidity and mortality. Superimposed on the lymphoma and the transplantation immunosuppression is a rare condition: hemophagocytic syndrome (HS). HS is characterized by fever, hepatosplenomegaly and lymphadenopathy, skin rashes, jaundice, coagulopathy, and phagocytosis of blood elements with pancytopenia. Here we describe a rare but fatal case of a kidney transplant patient who developed T-cell lymphoma and HS, without evidence of EBV replication. A short review of the diagnosis, treatment, and prognosis of HS is given.

[A case of IAHS (infection associated hemophagocytic syndrome) successfully treated with etoposide]

This report details a case of infection associated hemophagocytic syndrome (IAHS). A 20-year-old female was admitted to our hospital with persistent high fever in July, 1994. Physical examination revealed high body temperature (40 degrees C), marked hepatosplenomegaly and no superficial lymph node swelling. Laboratory examination revealed leukopenia and abnormal liver function on admission. Serum ferritin levels were surprisingly elevated. The coagulation tests showed high FDP and D-dimer. Specific viral antibody titers were not elevated such as Epstein-Barr virus or Cytomegalovirus. Bone marrow examination revealed histiocytic hyperplasia with hemophagocytosis, and the histiocytes were well matured. We diagnosed IAHS. Corticosteroids were administered on the 3rd hospital day (methylprednisolone 1 g/day, 3 days), but persistent high fever and laboratory findings did not improve. So we tried etoposide (etoposide 200 mg/day, 5 days) therapy on the 13th hospital day. After administration of etoposide, she failed to recover from severe leukopenia and suffered from meningitis. We administered G-CSF, gamma-globulin and antibiotics for intensive supportive therapy. As the leukocyte count increased, her symptoms and laboratory data improved. There was no hemophagocytosis in her bone marrow before discharge. Recently, etoposide is said to be effective for reactive monocytic proliferation. Administration of etoposide was very effective for IAHS, although corticosteroids, were ineffective.

[Hemophagocytic syndrome]

A lymph node biopsy sample from a boy aged with fever, pneumonia, hepatosplenomegaly, lymphadenopathy and pancytopenia, showed histiocytosis with erythrophagocytosis, compatible with the haemophagocytic syndrome. Treatment consisted of dexamethasone and etoposide, with cyclosporine added in a later phase. During the subsequent remission phase, bone marrow transplantation was carried out. Haemophagocytic syndrome is a rare condition, characterized by fever, pancytopenia, hepatosplenomegaly and characteristic laboratory findings (including a high interferon-gamma level) and morbid-anatomical findings (haemophagocytic histiocytic cells in bone marrow, lymph nodes, liver and spleen, but also in the CNS, kidneys and lungs). Recent pathophysiological discoveries indicate an enhanced T-cell response, leading to hypercytokinaemia. As a rule the patient dies from multiorgan failure and diffuse intravascular coagulation. Bone marrow transplantation is the treatment of choice.

Cytokine production regulating Th1 and Th2 cytokines in hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is caused by the hyperactivation of T cells and macrophages. The clinical characteristics associated with this disease result from overproduction of Th1 cytokines including interferon-gamma (IFN-gamma), interleukin-2 (IL-2), and tumor necrosis factor-alpha (TNF-alpha). In this study, we analyzed the production of IL-12 and IL-4, which determine Th1 and Th2 response, respectively, and IL-10, which antagonizes Th1 cytokines, in 11 patients with HLH. IL-12 was detected in plasma in all patients (mean peak value, 30.0 +/- 5.0 pg/mL), while IFN-gamma was massively produced in nine patients (mean peak value, 79.2 +/- 112.0 U/mL). IL-4 was not detected in any of the patients. Plasma IL-10 levels were elevated in all patients (mean peak value, 2,698.0 +/- 3,535.0 pg/mL). There was a positive correlation between the levels of IFN-gamma and IL-10 (P < .01). The plasma concentrations of these cytokines were initially high, before decreasing after the acute phase. However, the decrease in IL-10 levels was slower than that of IFN-gamma. Although the concentration of IL-12 was high at the acute phase, in some patients, a peak in the level was delayed until the chronic phase. Thus, in HLH, production of cytokines that promote development of Th1 cells appears to be predominant over that for Th2 cell development. Overproduction of IL-10 was also observed indicating that a mechanism suppressing hyperactivation of Th1 cells and monocytes/macrophages functions in patients with this disease.