Showing papers on "Hemophagocytic lymphohistiocytosis published in 2008"

Highly elevated ferritin levels and the diagnosis of hemophagocytic lymphohistiocytosis

Abstract: Background Hemophagocytic lymphohistiocytosis (HLH) is a potentially lethal condition characterized by a pathologic inflammation. The diagnostic criteria for HLH include fever, splenomegaly, cytopenias, hypertriglyceridemia, hypofibrinogenemia, abnormal natural killer cell (NK cell) functional assay, elevated soluble IL-2Rα level, and elevated ferritin level (>500 µg/L). Institution of timely therapy in these critically ill patients may be delayed by difficulties establishing the diagnosis. NK cell functional assay and soluble IL-2Rα level may require send-out to a specialized lab. However, ferritin level is available on a same-day basis at most institutions. In this study, we examined the utility of quantitative ferritin levels in diagnosing HLH. Procedure All patients with ferritin values >500 µg/L obtained at Texas Children's Hospital between January 10, 2003 and January 10, 2005 were identified. Patient charts were reviewed for ferritin levels and hospital course. Results During the study interval, 330 patients had ferritin levels >500 µg/L. Ten of the 330 patients were diagnosed with HLH. A ferritin level over 10,000 µg/L was 90% sensitive and 96% specific for HLH. Another diagnostic category with significantly elevated ferritin level was illness of unknown cause (n = 10), and only two of these patients were fully evaluated for HLH. Conclusions Ferritin levels above 10,000 µg/L appear to be specific and sensitive for HLH. In patients without a significant medical history and a new onset of febrile illness with highly elevated ferritin levels, the diagnosis of HLH should be evaluated. Pediatr Blood Cancer 2008;50:1227–1235. © 2007 Wiley-Liss, Inc.

Understanding organ dysfunction in hemophagocytic lymphohistiocytosis.

Abstract: Objective: This review aims to help critical care clinicians maintain a high level of suspicion regarding the diagnosis of Hemophagocytic Histiolymphocytosis (HLH). It describes the clinical and laboratory features of HLH, outlines its pathophysiology and reviews the most frequent etiologies related to HLH. Prognostic factors and therapeutic options are also reported. Data sources: Review of the literature. Results: The diagnosis of HLH relies on the association of clinical abnormalities and hemophagocytosis in bone marrow, spleen, or lymph node specimens. Liver, pulmonary, renal, cardiac and skin involvement may occur at various degrees possibly leading to multiple organ failure. Three main etiologies can be found, namely infections, lymphoproliferative diseases, or connective tissue diseases. Immune deficiency is often retrieved. Mortality can be as high as 50%. Although clinically mimicking severe sepsis, HLH has a distinct pathophysiology on which specific therapy is based. Early diagnosis and treatment is mandatory to increase the chances of survival. Conclusion: 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.

Macrophage activation syndrome in patients with systemic juvenile idiopathic arthritis is associated with MUNC13-4 polymorphisms.

Abstract: Macrophage Activation Syndrome (MAS) is a severe, potentially fatal condition associated with excessive activation of macrophages and T cells leading to an overwhelming inflammatory reaction. The main manifestations of MAS include fever, hepatosplenomegaly, lymphadenopathy, severe cytopenias, serious liver disease, and disseminated intravascular coagulation [1,2]. The pathognomonic feature of MAS is often found in bone marrow: numerous, well-differentiated macrophages phagocytosing hematopoietic elements. Although MAS has been reported in patients with different rheumatic diseases, it is most strongly associated with Systemic Juvenile Idiopathic Arthritis (SJIA). In fact, it accounts for much of the morbidity and mortality seen in this form of JIA. At least 10% of the patients with SJIA develop MAS [3]. The true incidence of MAS might be much higher since there are no validated diagnostic criteria and mild instances of MAS are not always recognized [4,5]. It is now recognized that MAS bears close resemblance to a group of histiocytic disorders collectively known as hemophagocytic lymphohistiocytosis (HLH) [2,6]. HLH is a term that describes a spectrum of disease processes characterized by accumulations of well-differentiated mononuclear cells with a macrophage phenotype [7]. In the contemporary classification of histiocytic disorders, HLH is further subdivided into primary, or familial HLH, and secondary, or reactive HLH (ReHLH) [7]. Clinically, however, they may be difficult to distinguish from each other [9]. Familial hemophagocytic lymphohistiocytosis (FHLH) is a constellation of rare autosomal recessive immune disorders. The clinical symptoms of FHLH usually become evident within the first 2 months of life although initial presentation as late as 22 years of age has been reported [8]. Secondary HLH tends to occur in older children and more often is associated with an identifiable infectious episode, most notably Epstein-Barr virus (EBV) or cytomegalovirus (CMV) infection. The exact pathophysiological relationship between MAS and HLH is not understood. Some pediatric rheumatologists view MAS as ReHLH occurring in a setting of a rheumatologic disease [6]. The pathological mechanisms of HLH/MAS are not fully understood. In HLH, there is uncontrolled proliferation of T cells and macrophages that has been linked to decreased NK-cell and cytotoxic T-cell function [10] often due to mutations in the gene encoding perforin [11]. Perforin is a protein which cytolytic cells utilize to induce apoptosis of target cells such as tumor cells or cells infected by viruses. It has been hypothesized by some authors that abnormal cytotoxic cells may fail to provide appropriate apoptotic signals for removal of activated macrophages and T cells during the contraction stage of certain immune responses [12]. Our recent observations suggest that as in HLH, MAS patients have profoundly depressed NK-cell function, often associated with abnormal perforin expression [13]. More recently, mutations in another gene, MUNC13-4, have been implicated in the development of hemophagocytic lymphohistiocytosis in about 10-30% of patients with inherited HLH [14]. The protein encoded by the MUNC13-4 gene is an essential effector of the cytolytic secretory pathway. MUNC13-4 protein is involved in vesicle priming function which follows granule docking and precedes plasma granule membrane fusion [14]. Therefore, it is an important player in the intracellular transport of perforin. Although the cytolytic cells of the patients with FHLH caused by MUNC13-4 mutations produce sufficient amounts of perforin, the poor ability to deliver perforin to the surface of the cells leads to profoundly decreased cytolytic activity against target cells. Here we present new data that suggests an association between MAS in SJIA and specific mutations and/or haplotypes in MUNC13-4 gene.

The use of reduced-intensity stem cell transplantation in haemophagocytic lymphohistiocytosis and Langerhans cell histiocytosis.

Abstract: Allogeneic stem cell transplant is curative for haemophagocytic lymphohistiocytosis (HLH) and refractory Langerhans cell histiocytosis (LCH). However, patients frequently have significant pre-transplant morbidity and there is high TRM. Because HLH is caused by immune dysregulation, we surmised that a reduced-intensity conditioned (RIC) regimen might be sufficient for cure, while decreasing the TRM. In 2006, we reported the outcome of 12 patients treated with RIC SCT from a matched family/unrelated or haploidentical donor. Here we discuss the update of these patients, including a total of 25 patients treated with RIC SCT for HLH and three for LCH. Twenty-one of the twenty-five patients with HLH (84%) are alive and well with remission at a median of 36 months from SCT. Mortality included pneumonitis (n=3) and hepatic rupture (n=1). All three patients treated with RIC SCT for LCH remain alive and in remission at a median of 5.1 years from SCT. Seven of twenty-four survivors (one with LCH) have mixed chimerism but remain disease-free. These data are supported by other groups including 100% survival in seven patients with HLH and 78% survival of nine patients with LCH. In summary, RIC compares favourably with conventional SCT with long-term disease control in surviving patients with both HLH and LCL, despite a significant incidence of mixed chimerism.

Mutations of the hemophagocytic lymphohistiocytosis-associated gene UNC13D in a patient with systemic juvenile idiopathic arthritis.

Abstract: The clinical syndromes of hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are both characterized by dysregulated inflammation with prolonged fever, hepatosplenomegaly, coagulopathy, hematologic cytopenias, and evidence of hemophagocytosis in the bone marrow or liver. While HLH is either inherited or acquired, children with severe rheumatic diseases, most notably systemic juvenile idiopathic arthritis, are at risk for MAS. The phenotypic similarity between HLH and MAS raises the possibility that they share common pathogenetic mechanisms. Familial forms of HLH have been attributed to mutations in the genes encoding perforin (PRF1) and Munc13-4 (UNC13D), among others, and are characterized by defective cytotoxic lymphocyte function. While some patients with systemic JIA have decreased levels of perforin protein expression and natural killer (NK) cell function, mutations of HLH-associated genes in patients with systemic JIA have not been reported. We report the case of an 8-year-old girl with systemic JIA without MAS who was found to have compound heterozygous mutations of UNC13D and reduced NK cell cytotoxic function. This case broadens the range of clinical phenotypes attributable to UNC13D mutations and offers new insights into the etiology and pathogenesis of systemic JIA.

Unrelated donor hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis

Abstract: We report outcomes after unrelated donor hematopoietic cell transplantation (HCT) for 91 patients with hemophagocytic lymphohistiocytosis (HLH) transplanted in the US in 1989–2005. Fifty-one percent were <1 year at HCT and 29% had Lansky performance scores <90%. Most (80%) were conditioned with BU, CY, and etoposide (VP16) with or without anti-thymocyte globulin. Bone marrow was the predominant graft source. Neutrophil recovery was 91% at day-42. The probabilities of grades 2–4 acute GVHD at day-100 and chronic GVHD at 5 years were 41 and 23%, respectively. The overall mortality rate was higher in patients who did not receive BU/CY/VP16-conditioning regimen (RR 1.95, P=0.035). The 5-year probability of overall survival was 53% in patients who received BU/CY/VP16 compared to 24% in those who received other regimens. In the subset of patients with known disease-specific characteristics, only one of five patients with active disease at HCT is alive. For those in clinical remission at HCT (n=46), the 5-year probability of overall survival was 49%. Early mortality rates after HCT were high, 35% at day-100. These data demonstrate that a BU/CY/VP16-conditioning regimen provides cure in approximately 50% of patients and future studies should explore strategies to lower early mortality.

Hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis: a journey of a thousand miles begins with a single (big) step.

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a rare, highly fatal disorder of uncontrolled inflammation, usually affecting infants. Significant progress in the treatment of this disorder has been achieved during the last decade, and outcomes for larger series of patients have been reported in recent years. Although medical therapy has advanced, hematopoietic cell transplantation remains the only curative therapy for patients with the familial form of this disorder. Unfortunately, these patients have demonstrated relatively poor post-transplant outcomes for a nonmalignant disorder, with approximately 30% mortality in the first 100 days. Early deaths were attributable to infection, GVHD, and unusually high rates of primary nonengraftment, venoocclusive disease and pneumonitis. In addition, a significant number of deaths were due to HLH reactivation, a unique complication seen in this patient group. In contrast, late complications were relatively infrequent and essentially all patients with durable engraftment remained in remission indefinitely. In this review, we will discuss recent progress in the transplant management of patients with HLH and potential future strategies, including the use of reduced intensity conditioning regimens.

Reduced intensity conditioning and allogeneic stem cell transplantation in childhood malignant and nonmalignant diseases.

Abstract: Allogeneic hematopoietic SCT is well established as a potentially curative therapy for children and adults with both malignant and nonmalignant diseases. However, myeloablative SCT is associated with significant short- and long-term complications. The goals of a reduced intensity-conditioning (RIC) regimen are to prevent graft rejection and establish stable donor-derived hematopoiesis at a level sufficient for cure of the underlying disease and, in patients with hematologic malignancy, to provide a GVL effect, while decreasing the short- and long-term complications associated with myeloablative conditioning therapy. RIC regimens have enabled SCT to be performed in children with preexisting comorbidities that preclude conventional conditioning. RIC-SCT has been most extensively studied in patients with nonmalignant disorders and for some of these, including primary immunodeficiencies and hemophagocytic lymphohistiocytosis, sufficient data now exist to support its routine use even in patients without comorbidity. Less data exist on RIC-SCT for children with hematologic malignancies and at present this should be restricted to children who are not candidates for, or have relapsed after, myeloablative SCT. Here we review available data on the use of RIC-SCT in pediatric patients, highlighting important clinical lessons and areas that require further study.

The role of hemophagocytosis in bone marrow aspirates in the diagnosis of hemophagocytic lymphohistiocytosis.

Abstract: HLH represents the most prevalent and clinically significant macrophage-related histiocytic disorder [1]. Although HLH was initially described as a familial disease [2], it is now clear that even patients without identifiable genetic mutations are at risk for HLH secondary to infections, malignancy, and rheumatological conditions [3,4]. The termmacrophage activation syndrome (MAS) has also been used in the literature. The diagnosis is based on a set of criteria, including genetic mutations, clinical features, laboratory abnormalities, and morphological evidence of hemophagocytosis (HPC) [5]. Genetic mutations in perforin [6], Munc 13-4 [7], and syntaxin 11 [4] can confirm the presence of familial disease, even in the older patients presenting with viral infections [8]. Children suspected ofHLH are often acutely ill and have non-specific clinical findings including fever, hyperferritinemia, hepatosplenomegaly and cytopenias. Thus a multi-disciplinary team approach is often required to confirm the diagnosis with involvement from general pediatrics, rheumatology, infectious disease and haematology/ oncology. Despite the exciting new findings related to the etiopathogenesis of this disease, until the aforementioned specialized genetic and immunological tests become available as routine clinical practice, there persists a lack of confirmatory diagnostic tests available to help the clinician in acute situations. It is often a consensus which navigates both diagnostic conclusions to rule in or out HLH and subsequent therapeutic approaches. Treatment can range from steroids and IVIG in mild cases to full protocol therapy including bone marrow transplantation for familial and severe patients, a distinction which can be anxiety-provoking both for families and the medical team. Even in institutions which perform specialized immunological and genetic testing, the results are usually not available in time to aid in immediate treatment-related decisions. The Munc-13 gene is extraordinarily long and it takes weeks to sequence the gene in its entirety. Furthermore, lowNK cell function and perforin analysis by flow cytometry, can be absent in up to 50% of patients with confirmed genetic abnormalities [9]. Thus, in order to have timely diagnosis, most practitioners continue to rely on the morphological presence of HPC in bone marrow (BM) to distinguish patients with simple infections or rheumatological disease from those with active HLH. Although sites most markedly affected include the splenic red pulp, hepatic portal areas, and lymph node sinuses [3,10], BM represents the most accessible place for morphological examination. BM examinations are relatively easy to organize, results are available the same day, and little risk is associated with the procedure compared to other tissue biopsies, especially in patients who are often acutely ill and coagulopathic. So, the multidisciplinary team often await the results of BM examinations in order to decide whether to diagnose the patient with and treat for HLH. Retrospective cohort analyses show that the majority of the patients have HPC at the time of diagnosis of HLH, suggesting that the diagnosis may be delayed until clinicians prove evidence of HPC [11]. HLH was initially identified and defined by the presence of hemophagocytosis, and some still maintain that it remains a morphological diagnosis [12]. However, it is clear that HPC are neither sensitive nor specific for HLH. The epiphenomenon of HPC is seen even following simple blood transfusions and surgery [13]. Furthermore, hemophagocytosis (HPC) is not always present at the time of the first BM examination in patients suspected of having HLH, and serial examinations are advocated [14]. HPC are found only at autopsy in some patients [15], such as in the original cases of HLH described by Farquhar and Claireaux [2]. There may be a different pattern of involvement of BM HPC in familial and secondary forms of HLH. It is possible that the familial cases are detected earlier in their disease course prior to the development of frank HPC. Others have commented that the degree of involvement is proportional to duration of symptoms and age of the patient. The later in life the disease started and the longer it lasted the ‘more apparent’ erythrophagocytic activity [16]. In young patients identified as having familial HLH due to a history of an affected sibling, HPCmay be absent until the onset of overt clinical symptomatology, and even then, may evolve over time requiring repeated marrow examinations [17]. Thus waiting for HPC to appear may unnecessarily delay appropriate therapy [5]. The number ofHPC required to define a positivemarrow inHLH also remains uncertain. The lack of standardized reporting of BM HPC, introduces variability in the interpretation of a positive finding. The attribution of HPC to the diagnosis of HLH may be more straightforward in situations where there is florid HPC [3], however, the finding of few HPC may not be informative. No quantitative data are available; however, it has been suggested that careful examination of at least three smears should reveal at least two HPC per slide to be significant [18]. Most studies lack information on the relative or absolute amount of HPC seen in tissues. Interpretation of the literature describing the prevalence of marrow involvement in HLH is limited by the variable diagnostic criteria used for study inclusion. A summary of these papers are listed in Table I, reporting variable BM involvement in aspirates or biopsies, ranging from 25 to 100% [3,15,16,19–25]. In combining the results of all the series listed in Table I, HPC inBMappearsmore likely to occur in secondary HLH compared to familial patients, with a Spearman correlation coefficient of 0.64, P1⁄4 0.046. Thus, BM are just as likely to be negative or positive for HPC in patients diagnosed with HLH. In summary, limited by the restriction of genetic and immunological testing to specialized centers and the delay in their reporting, BM HPC are often relied upon by clinicians, as early concrete diagnostic evidence to rule in and rule out HLH. HPC do not appear either sensitive nor specific, and there is marked heterogeneity in BM involvement among both familial and secondary forms of HLH. The problems are further confounded by lack of standardization and quantification of the reporting of HPC. Although there may be a

Allogeneic hematopoietic stem cell transplantation for Epstein-Barr virus-associated T/natural killer-cell lymphoproliferative disease in Japan.

Abstract: Epstein-Barr virus (EBV)-associated T/NK-cell lymphoproliferative disease (LPD) has been linked to several different disorders. Its prognosis is generally poor and a treatment strategy has yet to be established. There are reports, however, that hematopoietic stem cell transplantation (HSCT) can cure this disease. To clarify the current situation regarding allogeneic hematopoietic stem cell transplantation (allo-HSCT) for EBV-associated T/NK-LPD, a nationwide survey was performed in Japan. Data for 74 patients were collected. There were 42 cases of chronic active EBV infection (CAEBV), 10 cases of EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), and 22 cases of EBV-associated lymphoma/leukemia (EBV-lymphoma/leukemia). Of those with CAEBV, 54% had the EBV-infected T-cell type and 59% with EBV-lymphoma/leukemia had the EBV-infected NK-cell type. Most patients with EBV-HLH and EBV-lymphoma/leukemia received allo-HSCT within 1 year after onset compared to only 14% of patients with CAEBV. The event-free survival (EFS) rate following allo-HSCT was 0.561 +/- 0.086 for CAEBV, 0.614 +/- 0.186 for EBV-HLH, and 0.309 +/- 0.107 for EBV-lymphoma/leukemia. The EFS of allo-HSCT with conventional conditioning was 0.488 +/- 0.074 and with reduced-intensity conditioning was 0.563 +/- 0.124. Thus, in a substantial number of cases, EBV-associated T/NK-LPD can be cured by either allogeneic conventional stem cell transplantation or reduced-intensity stem cell transplantation.

Hematopoietic stem cell transplantation for hemophagocytic lymphohistiocytosis: a retrospective analysis of data from the Italian Association of Pediatric Hematology Oncology (AIEOP).

Abstract: Background Hemophagocytic lymphohistiocytosis is a life-threatening disease. Hematopoietic stem cell transplantation still represents the treatment of choice for most patients with this disease. Design and Methods We retrospectively analyzed 61 patients with hemophagocytic lymphohistiocytosis who underwent HSCT over a 17-year period at nine centers affiliated to the Italian Pediatric Hematology Oncology Association (AIEOP). The median time from diagnosis to hematopoietic stem cell transplantation was 0.6 years (range, 0.13–5). The donor for the first hematopoietic stem cell transplantation was either a relative (43%) or an unrelated volunteer (57%). Fifty-four patients (89%) had a complete genetic study, which led to the diagnoses of FHL2, due to perforin defect (21 patients), FHL3, due to Munc 13-4 defect (14 patients), Griscelli disease (2 patients), X-linked lymphoproliferative disease (1 patient), and CATCH22 syndrome (1 patient). No mutations were found in the remaining 15 patients. Twenty-one patients had neurological involvement at diagnosis. Results Three patients failed to engraft. Grade II–IV acute and chronic graft-versus-host disease occurred in 31% and 17% of patients, respectively. Overall, 39 patients are alive (64%), 15 died of toxicity, 6 of progressive disease and 1 of sudden death. The 8-year overall survival probability was 58.6% (95% confidence interval, 42–72), while the cumulative incidence of transplantation-related mortality was 25.7% (95% confidence interval, 16–40). The outcome of patients with a known genetic defect was comparable to that of patients without mutation. Neurological sequelae were reported in seven patients, six of whom had central nervous system disease at diagnosis. Conclusions These data confirm that hematopoietic stem cell transplantation represents a curative treatment for a large proportion of patients with hemophagocytic lymphohistiocytosis, irrespective of the underlying genetic defect.

Successful use of the anti-CD25 antibody daclizumab in an adult patient with hemophagocytic lymphohistiocytosis.

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a rare and severe inflammatory disorder marked by abnormal cytotoxic T and natural killer cell activity, resulting in impaired clearance of pathogen, excessive cytokine production, and continued immune system activation. Soluble IL-2 receptor (sIL-2R or sCD25) is typically elevated in HLH and can serve as a marker of disease activity, although its role in the pathophysiology of the disease is unclear. Here we present a case of an adult patient with steroid-dependent HLH who was treated successfully with daclizumab, a monoclonal anti-CD25 antibody, allowing successful withdrawal of steroid therapy without an increase in symptoms.

Hodgkin Lymphoma-Associated Hemophagocytic Syndrome : A Disorder Strongly Correlated with Epstein-Barr Virus

Abstract: The retrospective study of 34 patients with Hodgkin lymphoma-associated hemophagocytic syndrome led us to define this association as a specific disorder. Its characteristics are male predominance (male-to-female sex ratio, 3.3:1), immunodeficiency-like histological features (lymphocyte depletion, 45% of cases; mixed cellularity Hodgkin lymphoma subtype, 40%), and strong association with Epstein-Barr virus (94%).

A Griscelli syndrome type 2 murine model of hemophagocytic lymphohistiocytosis (HLH)

Abstract: Griscelli syndrome type 2 is caused by mutations in the RAB27A gene and is a rare and potentially fatal immune disorder associated with hemophagocytic lymphohistiocytosis (HLH). Animal models could provide assistance for better understanding the mechanisms and finding new treatments. Rab27a-deficient (ashen) mice do not spontaneously develop HLH. When injected with lymphocytic choriomeningitis virus (LCMV) strain WE, Rab27a-deficient C57BL/6 mice developed wasting disease, hypothermia, splenomegaly, cytopenia (anemia, neutropenia and thrombocytopenia), hypertriglyceridemia and increased levels of IFN-gamma, TNF-alpha, GM-CSF, IL-12, CCL5 and IL-10. Activated macrophages with hemophagocytosis were found in liver sections of these mice. Compared with perforin-deficient mice, LCMV-infected Rab27a-deficient mice showed a substantially better survival rate and slightly higher viral doses were needed to trigger HLH in Rab27a-deficient mice. This study demonstrates that LCMV-infected Rab27a-deficient C57BL/6 mice develop features consistent with HLH and, therefore, represent a murine model of HLH in human Griscelli syndrome type 2.

Hemophagocytic lymphohistiocytosis as severe adverse event of antineoplastic treatment in children.

Abstract: Hemophagocytic lymphohistiocytosis (HLH) during childhood cancer treatment is a rare adverse event posing major diagnostic and therapeutic challenges. Between 1995 and 2006, 6 children developed HLH while on conventional chemotherapy (n=4) or after allogeneic stem cell transplantation (n=2). Treatment of HLH included dexamethasone and etoposide, 2 children additionally received infliximab or daclizumab. Three children survived, whereas 3 children died 2, 5, and 47 days after diagnosis of HLH. HLH is a severe adverse event of childhood cancer therapy. Early diagnosis and immediate initiation of adequate treatment are mandatory to overcome this severe condition.

When T cells and macrophages do not talk: the hemophagocytic syndromes

Abstract: Purpose of review Hemophagocytic lymphohistiocytoses represent a rare but biologically and clinically important group of disorders. This review focuses on the clinical, pathophysiologic and genetic manifestations of these disorders along with critical aspects of timely and appropriate treatment. Recent findings Detailed laboratory investigations have led to significant advances in our understanding of the molecular and pathophysiologic features of hemophagocytic lymphohistiocytoses. These studies have provided new diagnostic tools and potential new therapeutic targets for future development. Parallel to these laboratory studies have been enormous advances in the treatment and improved clinical outcomes of patients with both primary and secondary hemophagocytic lymphohistiocytoses. The eventual merging of the improved understanding of the molecular pathway with novel gene therapy approaches may prove to be the final frontier in the optimal curative treatment of these disorders. Summary Several key molecular events have been defined which lead to a final common etiologic pathway of natural killer cell dysfunction leading to the hemophagocytic lymphohistiocytosis syndromes. In part through international clinical trials, effective curative therapies for about half of patients with severe forms of hemophagocytic lymphohistiocytosis have been developed. Although a significant advance, the fact that about 50% of patients are still not able to be cured with currently used approaches challenges physician-scientists to develop more innovative and effective diagnostic and therapeutic approaches.

Precursor B‐cell acute lymphoblastic leukemia presenting with hemophagocytic lymphohistiocytosis

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome which can be an inherited congenital disorder or can develop secondary to malignancy, infection, or autoimmune disease. Secondary HLH due to malignancy occurs most commonly with T or NK-cell lymphoid neoplasms. HLH with B-cell malignancies is less common and HLH has rarely been described in association with precursor B-cell acute lymphoblastic leukemia (B-ALL). We report three cases of HLH associated with B-ALL and review 17 cases of ALL-associated HLH previously reported in the literature. Pediatr Blood Cancer 2008;50:381–383. © 2006 Wiley-Liss, Inc.

The spectrum of Epstein-Barr virus-associated lymphoproliferative disease in Korea: incidence of disease entities by age groups.

Abstract: This study is to identify the spectrum of Epstein-Barr virus (EBV)-positive lymphoproliferative diseases (LPD) and relationships between these diseases in Korea. The EBV status and clinicopathology of 764 patients, including acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), chronic active EBV (CAEBV) infections, B-LPD arising in chronic latent EBV infection, T & natural killer (NK) cell non-Hodgkin's lymphomas (NHL), B-NHLs, and Hodgkin's lymphomas (HD), were analyzed. T or NK cell NHLs were the most common forms of EBV-positive NHLs (107/167, 64%); among these, nasal-type NK/T cell lymphomas were the most common (89/107, 83%). According to the age, Burkitt's lymphoma was the most common in early childhood; in teenagers, chronic (active) EBV infection-associated LPD was the most common type. The incidence of NK/T cell lymphoma began to increase from the twenties and formed the major type of EBV-associated tumor throughout life. Diffuse large B cell lymphoma formed the major type in the sixties and seventies. In conclusion, primary infections in early childhood are complicated by the development of CAEBV infections that are main predisposing factors for EBV-associated T or NK cell malignancies in young adults. In old patients, decreased immunity associated with old age and environmental cofactors may provoke the development of peripheral T cell lymphoma, unspecified, and diffuse large B cell lymphoma.

Treatment outcomes with CHOP chemotherapy in adult patients with hemophagocytic lymphohistiocytosis.

Abstract: The objective of the current study was to investigate the treatment outcomes for the use of cyclophosphamide, adriamycin, vincristine, and prednisolone (CHOP) chemotherapy in adult patients with hemophagocytic lymphohistiocytosis (HLH). Seventeen HLH patients older than 18 yr of age were treated with CHOP chemotherapy. A response evaluation was conducted for every two cycles of chemotherapy. With CHOP chemotherapy, complete response was achieved for 7/17 patients (41.2%), a partial response for 3/17 patients (17.6%), and the overall response rate was 58.8%. The median response duration (RD) was not reached and the 2-yr RD rate was 68.6%, with a median follow-up of 100 weeks. Median overall survival (OS) was 18 weeks (95% CI, 6-30 weeks) and the 2-yr OS rate was 43.9%. Reported grade 3 or 4 non-hematological toxicities were increased serum liver enzyme levels and stomatitis. Grade 3 or 4 hematological toxicities were leukopenia (50.8%), anemia (20%), and thrombocytopenia (33.9%). Neutropenic fever was observed in 21.6% of patients (14/65 cycles), and most of the cases were resolved with supportive care including treatment with broad-spectrum antibiotics. CHOP chemotherapy seems to be effective in adult HLH patients and the toxicities are manageable.

Increased serum monocyte chemoattractant protein‐1, macrophage inflammatory protein‐1β, and interleukin‐8 concentrations in hemophagocytic lymphohistiocytosis

Abstract: Background Hemophagocytic lymphohistiocytosis (HLH) is characterized by hypercytokinemia caused by macrophage and T cell activation. We analyzed the serum concentrations of monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1β, and interleukin (IL)-8 to investigate the roles of these chemokines in the pathophysiology of HLH. Methods Seven patients clinically diagnosed with HLH were examined. Serum cytokines and chemokines were measured. The differences in the serum concentrations between the patients with HLH and the controls were investigated. Results In patients with an active phase of HLH, the serum MCP-1, MIP-1β, and IL-8 levels all were significantly higher than in healthy controls. The chemokine elevations decreased rapidly after initiation of chemotherapy. During increases in disease activity, elevation of MCP-1 and MIP-1β preceded elevation of the serum ferritin level, which is a clinical indicator of HLH disease activity. Conclusions These results suggest that MCP-1, MIP-1β, and IL-8 play important roles in the pathophysiology of HLH. In addition, the serum concentrations of these chemokines may be sensitive markers for assessing disease activity in patients with HLH. Pediatr Blood Cancer 2008;51:662–668. © 2008 Wiley-Liss, Inc.

Poor Outcomes of Chronic Active Epstein-Barr Virus Infection and Hemophagocytic Lymphohistiocytosis in Non-Japanese Adult Patients

Abstract: Chronic active Epstein-Barr virus infection manifests as a combination of persistent infectious mononucleosis-like symptoms and high viral load in apparently immunocompetent patients. It is closely related to Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis. These 2 abnormal Epstein-Barr virus-associated diseases are seldom reported in individuals other than Japanese children and adolescents. We report a series of 2 adult non-Japanese patients with fatal chronic active Epstein-Barr virus and 1 adult non-Japanese patient with Epstein-Barr virus hemophagocytic lymphohistiocytosis and discuss its pathogenesis and treatment options.

Hemophagocytic lymphohistiocytosis preceded by Kikuchi disease in children

Abstract: Kikuchi disease (KD) is a type of benign, self-limiting lymphadenitis, but it has also been associated with hemophagocytic lymphohistiocytosis (HLH). To date, only a few reports have suggested an association between HLH and KD. To report the imaging findings and clinical characteristics of KD accompanied by HLH in children. Five children with a prolonged fever and cervical lymphadenopathy were diagnosed as having HLH accompanied by KD. The authors retrospectively analyzed the clinical characteristics and the imaging findings in these children. The histology of excision biopsy samples of cervical lymph nodes in all children confirmed the diagnosis of KD. HLH was confirmed by bone marrow biopsy and laboratory criteria provided by the Histiocyte Society. The greatest dimension of the enlarged nodes ranged from 0.5 cm to 2.5 cm and the nodes were most frequently located at level V. CT scans visualized perinodal infiltrates in most of the affected cervical nodes (four of five children) and extracervical nodes (three of three children). On enhanced CT scans, nonenhancing necrosis within the affected cervical nodes was noted in three children. KD might be related to HLH in children. Systemic evaluations and follow-up of children with KD might help to identify HLH related to KD.

Griscelli syndrome-type 2 in twin siblings: case report and update on RAB27A human mutations and gene structure

Abstract: Griscelli syndrome (GS) is a rare autosomal recessive disorder caused by mutation in the MYO5A (GS1, Elejalde), RAB27A (GS2) or MLPH (GS3) genes. Typical features of all three subtypes of this disease include pigmentary dilution of the hair and skin and silvery-gray hair. Whereas the GS3 phenotype is restricted to the pigmentation dysfunction, GS1 patients also show primary neurological impairment and GS2 patients have severe immunological deficiencies that lead to recurrent infections and hemophagocytic syndrome. We report here the diagnosis of GS2 in 3-year-old twin siblings, with silvery-gray hair, immunodeficiency, hepatosplenomegaly and secondary severe neurological symptoms that culminated in multiple organ failure and death. Light microscopy examination of the hair showed large, irregular clumps of pigments characteristic of GS. A homozygous nonsense mutation, C-T transition (c.550C>T), in the coding region of the RAB27A gene, which leads to a premature stop codon and prediction of a truncated protein (R184X), was found. In patient mononuclear cells, RAB27A mRNA levels were the same as in cells from the parents, but no protein was detected. In addition to the case report, we also present an updated summary on the exon/intron organization of the human RAB27A gene, a literature review of GS2 cases, and a complete list of the human mutations currently reported in this gene. Finally, we propose a flow chart to guide the early diagnosis of the GS subtypes and Chediak-Higashi syndrome.

Kawasaki disease associated with reactive hemophagocytic lymphohistiocytosis.

Abstract: We report a case of Kawasaki disease with significant coronary artery aneurysms subsequently associated with reactive hemophagocytic lymphohistiocytosis in a young child with low T-cell perforin expression and NK-cell dysfunction. The patient was treated with a selective T-cell costimulation modulator in an effort to regulate T-cells. This case is unique for several reasons: (1) the severe degree of coronary artery aneurysms; (2) low T-cell perforin and NK-cell values; and (3) treatment with a selective T-cell costimulation modulator, none of which has been described in prior cases.

Successful Treatment of Neonatal Herpes Simplex-Type 1 Infection Complicated by Hemophagocytic Lymphohistiocytosis and Acute Liver Failure

Abstract: Neonatal disseminated herpes simplex virus (HSV) infection with acute liver failure (ALF) and neonatal hemophagocytic lymphohistiocytosis (HLH) are severe diseases. We recently experienced a male infant with HLH and ALF induced by HSV type 1 (HSV-1). The infant, born at 39 weeks of gestation by normal delivery, developed a fever on day 4. On day 9, laboratory investigations showed progressive liver dysfunction and coagulopathy, and the serum ferritin was excessively elevated. Furthermore, the blood levels of interleukin (IL)-6, IL-10, and interferon-gamma were also elevated. HSV-1 DNA was detected in the serum and cerebrospinal fluid by the real-time PCR method. A diagnosis of HLH was established based upon the following criteria: fever, splenomegaly, cytopenia (two cell lines), serum ferritin (> 500 μg/l) and hypofibrinogenemia (< 150 mg/dl). High-dose acyclovir therapy, steroid pulse therapy using methylprednisolone, high-dose gamma globulin therapy and a blood transfusion were given. The patient recovered without neurological deficit. Neonatal disseminated HSV infections may be complicated by the development of HLH and hypercyokinemia. If HLH is suspected, not only high-dose acyclovir therapy but also anti-cytokine therapy should be considered.

A teenage boy with late onset hemophagocytic lymphohistiocytosis with predominant neurologic disease and perforin deficiency.

Abstract: Familial hemophagocytic lymphohistiocytosis (FHLH) is an autosomal recessive disorder of cytotoxic cell function that results in abnormal proliferation of benign lymphocytes and histiocytes in response to infectious stimuli. FHLH generally occurs in very young children, and typically presents with fever, cytopenias, coagulopathy, lymphadenopathy, and hepatosplenomegaly. Central nervous system involvement occurs frequently and may precede the development of systemic symptoms by months to years. We report a case of an 18-year-old male with a 2-year history of symptoms attributed to a demyelinating disorder, who succumbed to rapidly progressive hemophagocyte lymphohistiocytosis. Post-mortem, two distinct perforin mutations were identified. We discuss the central nervous system and genetic findings in this unusual presentation of familial hemophagocytic lymphohistiocytosis. Pediatr Blood Cancer 2008;50:1070–1072. © 2007 Wiley-Liss, Inc.

Genetic loci contributing to hemophagocytic lymphohistiocytosis do not confer susceptibility to systemic-onset juvenile idiopathic arthritis.

Abstract: OBJECTIVE: To investigate whether single-nucleotide polymorphisms (SNPs) within the genes PRF1, GZMB, UNC13D, and Rab27a, which are involved in natural killer cell dysfunction and known to contribute to the risk of hemophagocytic lymphohistiocytosis (HLH), confer an increased risk of susceptibility to systemic-onset juvenile idiopathic arthritis (JIA). METHODS: Four SNPs across the PRF1 gene locus, 5 for GZMB, 7 for UNC13D, and 11 for Rab27a were investigated using MassArray genotyping in 133 UK Caucasian patients with systemic-onset JIA and 384 ethnically matched unrelated control subjects. Additional control genotypes were accessed from the data generated by the Wellcome Trust Case Control Consortium. RESULTS: No significant association was found between any SNP within the 4 selected loci and systemic-onset JIA, by either single-point or haplotype analysis. CONCLUSION: The results of this study demonstrate that genes involved in HLH do not confer a significant risk of association with systemic-onset JIA.