Showing papers on "Hemophagocytic lymphohistiocytosis published in 2012"

Familial and acquired hemophagocytic lymphohistiocytosis.

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome in which an uncontrolled and ineffective immune response, triggered in most cases by infectious agents, leads to severe hyperinflammation. Familial forms of HLH (FHL), which are increasingly found also in adolescents and adults, are due to genetic defects leading to impaired function of natural killer cells and cytotoxic T cells. These mutations occur either in the perforin gene or in genes important for the exocytosis of cytotoxic granules. Cytotoxic granules contain perforin and granzymes, which induce apoptosis upon entering (infected) target cells. Additionally, perforin is important for the downregulation of the immune response. Acquired forms of HLH are encountered in association with (usually) viral infections, autoinflammatory/autoimmune diseases, malignant diseases, and acquired immune deficiency states (e.g., after organ transplantation). Treatment of HLH includes immune-suppressive and immune-modulatory agents, cytostatic drugs, and biological response modifiers. For patients with FHL, stem cell transplantation is indicated and can be curative.

Hemophagocytic lymphohistiocytosis: updates and evolving concepts.

Abstract: Purpose of reviewHemophagocytic lymphohistiocytosis (HLH) is an immune dysregulatory syndrome that is associated with underlying defects of perforin-dependent cytotoxic function. This review seeks to update readers on new scientific insights and evolving clinical concepts related to this rare but fa

Recent advances in the diagnosis and treatment of hemophagocytic lymphohistiocytosis

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a rare life-threatening disease of severe hyperinflammation caused by uncontrolled proliferation of activated lymphocytes and macrophages secreting high amounts of inflammatory cytokines. It is a frequent manifestation in patients with predisposing genetic defects, but can occur secondary to various infectious, malignant, and autoimmune triggers in patients without a known genetic predisposition. Clinical hallmarks are prolonged fever, cytopenias, hepatosplenomegaly, and neurological symptoms, but atypical variants presenting with signs of chronic immunodeficiency are increasingly recognized. Impaired secretion of perforin is a key feature in several genetic forms of the disease, but not required for disease pathogenesis. Despite progress in diagnostics and therapy, mortality of patients with severe HLH is still above 40%. Reference treatment is an etoposide-based protocol, but new approaches are currently explored. Key for a favorable prognosis is the rapid identification of an underlying genetic cause, which has been facilitated by recent immunological and genetic advances. In patients with predisposing genetic disease, hematopoietic stem cell transplantation is performed increasingly with reduced intensity conditioning regimes. Current research aims at a better understanding of disease pathogenesis and evaluation of more targeted approaches to therapy, including anti-cytokine antibodies and gene therapy.

Clinical features of adult patients with secondary hemophagocytic lymphohistiocytosis from causes other than lymphoma: an analysis of treatment outcome and prognostic factors

Abstract: Although hemophagocytic syndrome (HS) featuring secondary hemophagocytic lymphohistiocytosis (HLH) has a grave prognosis, little is known about the natural course of the disease. Patients who showed the clinical features of HLH as well as tissue-proven hemophagocytosis when seen at Asan Medical Center between 1999 and 2010 were included in this analysis. Patients with proven lymphoma were excluded. The median age of our 23 study patients was 49 years. Epstein–Barr virus was suspected to have caused HS in 16 (70%) patients and hepatitis A virus in one patient. Twenty-two patients were treated, 13 according to the HLH protocol and nine using immunosuppressive agents such as corticosteroid and/or cyclosporine. Five patients undertook allogeneic hematopoietic cell transplantation (HCT) during their treatment-dependent relapse (n = 4) or responsive status (n = 1). After the median follow-up of 180 days, 17 (74%) died and six (26%) were alive. The median time from initial presentation until death was 41 days among those patients who died. The serum fibrinogen level ≥166 mg/dL determined at the initial visit was significantly associated with the survival time according to univariate analysis. The low histiocyte proportion in bone marrow and early initiation of treatment tended to correlate with a favorable outcome. On multivariate analysis, serum fibrinogen ≥166 mg/dL (hazard ratio, 0.175, P = 0.018) was an independent clinical factor for determining the patient survival time. Despite appropriate patient management, the outcome of HS featuring HLH was grave. The serum fibrinogen level at the initial presentation was significant, and selected patients obtained some benefit from allogeneic HCT.

Sensitivity and specificity of bone marrow hemophagocytosis in hemophagocytic lymphohistiocytosis.

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal disease characterized by abnormal activation of T-lymphocytes and macrophages. The diagnosis of HLH can be established if there is a family history of HLH, or evidence of genetic defects, or if 5 of 8 clinicopathologic criteria are fulfilled. This case-control study aimed to examine the extent of hemophagocytosis on the bone marrow examination of patients fulfilling diagnostic criteria for HLH. Hemophagocytosis in 6 bone marrow aspirates from 3 HLH patients was compared with 20 random control bone marrows. Macrophages with hemophagocytosis were counted using a Miller ocular disc in fields corresponding to 9,000 nucleated cells. Mean hemophagocytosis count in the HLH cases was estimated at 0.082% (range 0-0.31%), whereas in the controls it was 0.009% (range 0-0.04%). The sensitivity of hemophagocytosis was 83% with a specificity of only 60%. This demonstrates that rare hemophagocytosis can be seen in bone marrow aspirates from patients without a clinical diagnosis of HLH. It also shows that hemophagocytosis has too low a specificity to be a screening test for HLH. While the hemophagocytosis counts are significantly higher in HLH cases than in controls, overlap of the counts precludes using hemophagocytosis as a reliable indicator of HLH. A rise in the hemophagocytosis count threshold of 0.05-0.13% would increase the specificity to 100%. We suggest that the diagnostic scheme for HLH needs revision, and can be improved by addressing minimum hemophagocytosis count threshold.

药联系了与 hemophagocytic lymphohistiocytosis 相结合的消失的胆汁管症候群

Abstract: A 28-year-old woman with untreated autoimmune disorder, demonstrated skin rash and fever after taking Amoxicillin-clavulanate and developed progressive jaundice. A bone marrow aspiration indicated an increased number of macrophages with hemophagocytosis and liver biopsy showed pure centrilobular cholestasis with necrosis and some absence of portal bile ducts. Furthermore, a serological test for Epstein-Barr virus was positive. Under treatment by liver dialysis and administration of steroids led to rapidly defervescence and clinical improvement. However, liver enzymes were still markedly elevated with persistent anemia, even after immunosuppressive treatment. The patient is currently waiting for liver transplantation. This is the first description of vanishing bile duct syndrome combined with hemophagocytic lymphohistiocytosis, with underlying causes including infection, drug-induced factors and untreated autoimmune disorder.

Clinical and genetic characteristics of XIAP deficiency in Japan.

Abstract: Deficiency of X-linked inhibitor of apoptosis (XIAP) caused by XIAP/BIRC4 gene mutations is an inherited immune defect recognized as X-linked lymphoproliferative syndrome type 2. This disease is mainly observed in patients with hemophagocytic lymphohistiocytosis (HLH) often associated with Epstein–Barr virus infection. We described nine Japanese patients from six unrelated families with XIAP deficiency and studied XIAP protein expression, XIAP gene analysis, invariant natural killer T (iNKT) cell counts, and the cytotoxic activity of CD8+ alloantigen-specific cytotoxic T lymphocytes. Of the nine patients, eight patients presented with symptoms in infancy or early childhood. Five patients presented with recurrent HLH, one of whom had severe HLH and died after cord blood transplantation. One patient presented with colitis, as did another patient’s maternal uncle, who died of colitis at 4 years of age prior to diagnosis with XIAP deficiency. Interestingly, a 17-year-old patient was asymptomatic, while his younger brother suffered from recurrent HLH and EBV infection. Seven out of eight patients showed decreased XIAP protein expression. iNKT cells from patients with XIAP deficiency were significantly decreased as compared with age-matched healthy controls. These results in our Japanese cohort are compatible with previous studies, confirming the clinical characteristics of XIAP deficiency.

Secondary hemophagocytic lymphohistiocytosis in adults: an update on diagnosis and therapy.

Abstract: Hemophagocytic lymphohistiocytosis (HLH), also known as hemophagocytic syndrome (HPS), is a rare, life-threatening, hematologic disorder manifested by clinical findings of extreme inflammation and unregulated immune activation. In both its congenital (primary) and adult (secondary) forms, it is most often characterized by fevers, hepatomegaly or splenomegaly, and bi- or trilineage cytopenias. In addition, elevated liver enzymes, hyperferritinemia, hypertriglyceridemia, and hypofibrinogenemia are commonly seen in HLH patients. A high index of suspicion is necessary for early diagnosis. Furthermore, a thorough diagnostic evaluation is necessary, and prompt treatment of the underlying causes is key in order to prevent irreversible tissue damage. Here we discuss the clinical signs, diagnosis, and treatments associated with this rare and potentially lethal disorder as manifested in adults.

Protection from Inflammatory Organ Damage in a Murine Model of Hemophagocytic Lymphohistiocytosis Using Treatment with IL-18 Binding Protein

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition due to the association of an infectious agent with lymphocyte cytotoxicity defects, either of congenital genetic origin in children or presumably acquired in adults. In HLH patients, an excess of lymphocyte or macrophage cytokines, such as IFN-γ and TNFα is present in serum. In animal models of the disease, IFN-γ and TNF-α have been shown to play a central pathogenic role. In humans, unusually high concentrations of IL-18, an inducer of IFN-γ and TNF-α have been reported, and are associated with an imbalance between IL-18 and its natural inhibitor IL-18 binding protein (IL-18BP) resulting in an excess of free IL-18. Here we studied whether IL-18BP could reduce disease severity in an animal model of HLH. Mouse cytomegalovirus infection in perforin-1 knock-out mice induced a lethal condition similar to human HLH characterized by cytopenia with marked inflammatory lesions in the liver and spleen as well as the presence of hemophagocytosis in bone marrow. IL-18BP treatment decreased hemophagocytosis and reversed liver as well as spleen damage. IL-18BP treatment also reduced both IFN-γ and TNF-α production by CD8+ T and NK cells, as well as Fas ligand expression on NK cell surface. These data suggest that IL-18BP is beneficial in an animal model of HLH and in combination with anti-infectious therapy may be a promising strategy to treat HLH patients.

Central nervous system (CNS) involvement is a critical prognostic factor for hemophagocytic lymphohistiocytosis

Abstract: Background Hemophagocytic lymphohistiocytosis (HLH) is a rare multisystem disorder that frequently involves the central nervous system (CNS). We compared the clinical characteristics, treatment, and prognosis of patients with HLH according to the degree of CNS involvement.

Secondary Hemophagocytosis in 3 Patients With Organic Acidemia Involving Propionate Metabolism

Abstract: Hemophagocytic lymphohistiocytosis (HLH) may develop secondary to infections, malignancies, immune deficiency syndromes, and rheumatologic and metabolic disorders. Associations between HLH and inborn errors of metabolism, including lysinuric protein intolerance, multiple sulfatase deficiency, galactosemia, Gaucher disease, Pearson syndrome, and galactosialidosis, have previously been reported in the literature. In this report the authors present 3 children with disorders of propionate metabolism--1 with methylmalonic acidemia and 2 with propionic acidemia--who developed secondary HLH during their metabolic attacks. All patients fulfilled the 5 HLH criteria of the Histiocyte Society. Familial HLH was ruled out by molecular analysis. Plasma exchange was performed for 2 of them. Unfortunately 1 died of multiorgan failure despite intensive therapy. This is the first report of such an association.

Intravenous immunoglobulin treatment for macrophage activation syndrome complicating chronic granulomatous disease.

Abstract: Objectives Chronic granulomatous disease is a rare phagocyte disorder characterized by an increased susceptibility to infections and inflammatory complications. We describe two patients with chronic granulomatous disease (CGD) complicated by macrophage activation syndrome (MAS) (secondary hemophagocytic lymphohistiocytosis) treated with intravenous immunoglobulin (IVIG). Methods A report of two cases of CGD complicated by MAS who were successfully treated with IVIG was made, and a comparison was made with ten other cases reported in the literature. Results MAS is a severe potentially fatal complication of CGD. Most cases are associated with Burkholderia cepacia and leishmaniasis infection. The treatment of these patients varies between centers, and one example is the use of the HLH-2004 protocol. IVIG could be an effective first line option for this complication in CGD patients. Conclusions The exaggerated inflammatory response characteristic of CGD patients could play a role in the development of this complication. IVIG appears to be a safe and effective first line treatment in these patients.

What intensivists need to know about hemophagocytic syndrome: an underrecognized cause of death in adult intensive care units.

Abstract: Hemophagocytic syndrome, also known as hemophagocytic lymphohistiocytosis (HLH), is a rare and frequently fatal disorder caused by an uncontrollable and ineffective systemic immune response. Patients initially present with fever, cytopenia, and hepatosplenomegaly, and subsequently develop multiorgan failure (MOF). Hemophagocytosis can be found on biopsy specimen but is not required. Acquired forms of HLH can occur in apparently healthy adults, while children present more often with an inherited form of the disease. Since HLH often presents with sepsis-like symptoms and organ dysfunction, patients are usually treated for presumed sepsis, which inevitably leads to delayed diagnosis and treatment. Intensivists need to have a low threshold for suspecting this disorder when previously healthy individuals present with a fulminant sepsis-like syndrome, which are unresponsive to conventional treatment. We present 3 patients with HLH who were admitted to our adult medical intensive care unit (MICU) over a 2-year period with fatal outcomes and emphasize the diagnostic importance of markedly elevated serum ferritin levels and the need for tissue biopsy in making an accurate diagnosis in a timely manner.

Diagnosing and treating hemophagocytic lymphohistiocytosis in the tropics: systematic review from the Indian subcontinent.

Abstract: Background. Hemophagocytic lymphohistiocytosis (HLH) is a catastrophicsyndrome of unrestrained immune activation. Evaluationand management of HLH in the tropics is challenging. Objectives. Toexamine the reported etiologies and management of HLH reportedfrom the sub-continent. Methods. Systematic review of all publishedcases from the Indian sub-continent. Results. We found only 156 publishedcases of HLH from the sub-continent. HLH was reported fromthe immediate perinatal period to 46 years of age. Infection-associatedHLH (IAHS) constituted 46.8% of all cases of HLH (44% and 51%in children and adults respectively). In adults, tropical infections triggered51% of these cases of IAHS. Steroids were used in 47% of childrenand 10% of adults. Etoposide and/or cyclosporine were used in8% children and 8% of adults only. Intravenous immunoglobulin wasused in another 30% of children and 4% of the adults. HLH-relatedmortality occurred in 31.8% and 28% of children and adults respectively.Conclusions. HLH is under-reported in the sub-continentand has high mortality. Cyclosporine and etoposide are seldom administeredearly despite diagnosis of HLH. Larger cohorts with IAHStriggered by tropical infections are urgently needed to understand itsnatural history and implications of this differing prescription patternon mortality.

Griscelli syndrome types 1 and 3: analysis of four new cases and long-term evaluation of previously diagnosed patients.

Abstract: Griscelli syndrome (GS) is a rare autosomal recessive disorder characterized by partial albinism. Three different types are caused by defects in three different genes. Patients with GS type 1 have primary central nervous system dysfunction, type 2 patients commonly develop hemophagocytic lymphohistiocytosis, and type 3 patients have only partial albinism. While hematopoietic stem cell transplantation is life saving in type 2, no specific therapy is required for types 1 and 3. Patients with GS types 1 and 3 are very rare. To date, only 2 patients with type 3 and about 20 GS type 1 patients, including the patients described as Elejalde syndrome, have been reported. The neurological deficits in Elejalde syndrome were reported as severe neurodevelopmental delay, seizures, hypotonia, and ophthalmological problems including nystagmus, diplopia, and retinal problems. However, none of these patients' clinical progresses were reported. We described here our two new type 1 and two type 3 patients along with the progresses of our previously diagnosed patients with GS types 1 and 3. Our previous patient with GS type I is alive at age 21 without any other problems except severe mental and motor retardation, patients with type 3 are healthy at ages 21 and 24 years having only pigmentary dilution; silvery gray hair, eye brows, and eyelashes. Since prognosis, treatment options, and genetic counseling markedly differ among different types, molecular characterization has utmost importance in GS.

SAP and XIAP deficiency in hemophagocytic lymphohistiocytosis

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a multisystem inflammatory disorder due to cytokine overproduction from excessively activated lymphocytes and macrophages. HLH has been divided into two subgroups: primary HLH and secondary HLH. Primary HLH includes PRF1, UNC13D, STX11, STXBP2, RAB27A, LYST, SH2D1A and XIAP gene mutations; and secondary HLH is associated with infections, malignancies and autoimmune diseases. Among primary HLH-related genes, SH2D1A and XIAP are genetically responsible for X-linked lymphoproliferative syndrome (XLP) due to signaling-lymphocytic-activation-molecule-associated protein (SAP) and XIAP deficiencies, respectively. XLP is characterized by extreme vulnerability to Epstein-Barr virus infection. The major clinical manifestations of XLP consist of HLH (60%), lymphoproliferative disorder (30%) and dysgammaglobulinemia (30%). Analysis of clinical phenotypes of XLP patients suggests that XLP predominantly shows familial HLH phenotypes, whereas some XLP patients present sporadic HLH. For many decades, clinicians and investigators have been concerned with possible XLP in young boys presenting with Epstein-Barr-virus-associated HLH. This review aims to describe the new knowledge about XLP and to draw the attention of the pediatrician to XLP, which should be differentiated from other forms of HLH.

Hemophagocytic lymphohistiocytosis in pregnancy: a case report and review of treatment options

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening inflammatory disorder characterized by uncontrolled proliferation and activation of histiocytes with phagocytosis of normal hematopoietic cells. A 41-year-old woman, 19 weeks pregnant with twins, and a history of Still's disease, presented with rash, fever, and headache. Laboratory studies revealed transaminitis, hyperbilirubinemia, and eventually severe neutropenia as well as elevations in ferritin, lactate dehydrogenase, and C-reactive protein. A bone marrow biopsy confirmed HLH. She declined standard HLH-treatment but responded well to high-dose corticosteroids. Her blood counts remained stable following corticosteroid taper, and she delivered healthy twin girls at 30-week gestation. Few cases of HLH during pregnancy have been reported. In some cases, the condition has proved fatal. Therefore recognizing signs and symptoms of HLH is essential to avoid treatment delay. In our case, high-dose corticosteroids alone were a safe and effect...

Severe hemophagocytic lymphohistiocytosis in adults-experience from an intensive care unit from North India.

Abstract: Background: Hemophagocytic lymphohistiocytosis (HLH) has been reported to complicate fulminant tropical infections but data on severe HLH with multi-organ dysfunction (MODS) are scant. Materials and Methods: Retrospective review of medical electronic records of our intensive care unit (ICU) over a 2-year period. Results: We describe 10 adult patients with HLH and MODS. Patients had short symptom duration prior to presentation and had rapid deterioration during their hospitalization course. Fever, organomegaly, neurologic abnormalities, hepatic abnormalities, and cutaneous signs were very common. No patient had diagnosed HLH at ICU admission (median 4 criteria [Inter Quartile Range 2-4.25]). All patients required mechanical ventilation and 80% required vasopressors. Infection-associated HLH (IAHS) was the most common etiology (80%). Seventy percent (7/10) of patients were treated with steroids and 20% received intravenous immunoglobulin. Etoposide and/or cyclosporine were administered in 20% (2/10). Nosocomial infections occurred in 40% and the ICU mortality was 70%. Conclusions: Severe HLH with MODS has a very high mortality. Data on adult cohorts with IAHS in the tropics with defined treatment protocols are urgently needed.

Successful treatment of recurrent malignancy-associated hemophagocytic lymphohistiocytosis with a modified HLH-94 immunochemotherapy and allogeneic stem cell transplantation

Abstract: Acquired hemophagocytic lymphohistiocytosis (HLH) triggered by a known or still to be recognized malignancy is a life-threatening hyperinflammatory syndrome due to massive cytokine release from activated lymphocytes and macrophages. Malignancy-associated HLH (M-HLH) often impedes adequate treatment of malignancy and has the worst outcome compared with any other form of HLH. The incidence of M-HLH is unknown, and there are no published treatment recommendations addressed to this HLH form. Here, we report the case of a young woman with recurrent ALK1-positive anaplastic large T-cell lymphoma and M-HLH successfully treated with a modified HLH-94 protocol, allogeneic stem cell transplantation (alloSCT) and donor lymphocyte infusion (DLI). More than 3 years after DLI, the patient is alive, in complete remission from her malignancy and HLH-free, although suffering from extensive chronic graft-versus-host disease. AlloSCT and, if needed, DLI performed to consolidate remission of malignancy and HLH may have a curative impact on both entities. We propose that when discussing possible treatment options for patients with M-HLH, alloSCT should be considered in eligible individuals.

Flow Cytometric Findings in Hemophagocytic Lymphohistiocytosis

Abstract: Hemophagocytic lymphohistiocytosis (HLH) is an often fatal hyperinflammatory syndrome. HLH may be inherited, but it more commonly arises secondary to Epstein-Barr virus (EBV) or other infections, hematologic malignancies, or rheumatologic diseases. We identified 17 patients diagnosed with HLH who had flow cytometric analysis of peripheral blood or bone marrow performed at the time of diagnosis. Two patients had primary HLH, and the others had HLH secondary to EBV infection, hematologic malignancies, rheumatologic conditions, or tuberculosis. The marrow typically showed a reactive lymphocytosis and a marked left shift in myelopoiesis regardless of the etiology. Qualitative abnormalities were also found in several cases, including T-cell abnormalities in the majority of the EBV-associated HLH cases. While not specific, flow cytometric findings in HLH are different from the findings in uninvolved marrow samples, and care should be taken not to overinterpret immunophenotypic findings in these cases as indicative of a primary marrow disorder or lymphoma.

Treatment choice of immunotherapy or further chemotherapy for Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis.

Abstract: Background Epstein–Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) leads to an aggressive and often fatal course without appropriate treatment. Etoposide therapy is crucial for the better prognosis, although it remains unknown what patients need cytotoxic agents. Since we have complied with step-up strategy in a tertiary center, treatment outcomes were studied to search predictors for disease course. Methods The study enrolled 22 EBV-HLH patients treated between 1999 and 2010 in Kyushu University. Immunotherapy, chemotherapy and stem cell transplantation (SCT) proceeded in stages unless patients attained a consecutive >21 days-afebrile remission. Clinical and laboratory data and outcomes were retrospectively analyzed. Results Median age of 9 males and 13 females was 5 years (range: 9 months–41 years). Sixteen patients (73%) presented at age <15 years. Two patients remitted spontaneously, 12 attained remissions after immunotherapy, 5 after chemotherapy, and 1 after successful SCT. The remaining two patients died after chemotherapy and SCT, respectively. Median EBV load was 1 × 105 copies/ml of peripheral blood (range: 200–5 × 107). T-cells were exclusively targeted (94%; 15/16 examined) often with EBV/T-cell receptor clonality. EBV status indicated 19 primary infections and 3 reactivations. Either death occurred in EBV-reactivated patients who underwent chemotherapy ± SCT. Age at primary infection in pediatric patients increased in the last 5 years. Patients having prolonged fever (P = 0.017) or high soluble CD25 levels (P = 0.017) at diagnosis were at higher risk for requiring chemotherapy assessed by multivariate analyses. Conclusions No cytotoxic agents were needed for >60% of EBV-HLH patients. Early immunotherapy may modulate T-cell activation and reduce the chance of unnecessary chemotherapy. Pediatr Blood Cancer 2012;59:265–270. © 2011 Wiley Periodicals, Inc.

Hemophagocytic lymphohistiocytosis after hematopoietic stem cell transplantation in children: A nationwide survey in Japan

Abstract: Background Hemophagocytic lymphohistiocytosis (HLH) is associated with hypercytokinemia in children. Although HLH can be also observed after hematopoietic stem cell transplantation (HSCT), the incidence and clinical features of HLH after HSCT remain obscure. Procedure The clinical features of HLH after HSCT (post-HSCT HLH) were investigated in children with malignancies, immune deficiencies, or aplastic anemia. The HLH/Langerhans Cell Histiocytosis (LCH) Committee of the Japanese Society of Pediatric Hematology (JSPH) sent questionnaires to hospitals with JPSH members asking for details of cases in which HLH occurred after HSCT between 1998 and 2008. Results Among 42 children who were diagnosed with post-HSCT HLH between 1998 and 2008 in Japan, 37 fulfilled our inclusion criteria; of these, 26 were classified as early-onset (onset 30 days after HSCT). In the early-onset group, the presence of respiratory symptoms, high levels of total bilirubin, and triglycerides at onset and the lack of control of GVHD with tacrolimus were significantly associated with non-resolution of HLH (P < 0.05). The survival rate was significantly higher in patients with resolution of HLH than in those without resolution (59% vs. 14%, P < 0.05). Conclusions These findings suggest that early-onset post-HSCT HLH is a specific entity of HLH, and appropriate diagnosis and prompt management need to be established. Pediatr Blood Cancer 2012; 59: 110–114. © 2011 Wiley Periodicals, Inc.