Rate of decline of ferritin in patients with hemophagocytic lymphohistiocytosis as a prognostic variable for mortality

Hemophagocytic lymphohistiocytosis (HLH) is difficult to diagnose and treat. Highly elevated ferritin is strongly associated with HLH and levels may provide a prognostic marker. A comprehensive review of ferritin data from our patients during treatment was analyzed with respect to mortality. A patient was 17 times more likely to die when percent ferritin decrease was less than 50% as compared to a 96% or greater decrease as indicated with multivariate logistic modeling. Higher maximum ferritin levels in the first 3 weeks also contributed to the odds of death (OR = 5.6; 90% CI = 1.2–24.9). Regular ferritin measurements may be useful predicting outcomes in HLH patients. Pediatr Blood Cancer. 2010;56:154–155. © 2010 Wiley‐Liss, Inc.     

Ehrlichia-induced hemophagocytic lymphohistiocytosis in two children

Two children presented with a history of fever and rash. Lab values revealed pancytopenia, elevated ferritin, coagulopathy, and elevated triglycerides. Both children quickly developed respiratory distress and hypotension requiring admission to the ICU. Bone marrow biopsies revealed hemophagocytosis. Studies for Ehrlichia returned positive. The patients were started on doxycycline and treated for hemophagocytic lymphohistiocytosis (HLH). Each made a full recovery. In both patients, testing for MUNC and perforin genes were found to have no mutation. These two cases demonstrate the importance of considering Ehrlichiosis as a possible trigger of HLH.     

Salvage therapy for refractory hemophagocytic lymphohistiocytosis: A review of the published experience

Hemophagocytic lymphohistioytosis (HLH) is a severe, life‐threatening hyperinflammatory disorder that requires prompt diagnosis and treatment. Approximately, 25–50% of patients with HLH fail to achieve remission with established regimens that include dexamethasone and etoposide, or methylprednisolone and antithymocyte globulin (ATG). Some of these patients may require salvage or alternative therapeutic approaches. There is a paucity of literature regarding effective salvage therapies for patients with refractory HLH. In this review, we summarize the published experience of four therapeutics reported for using at least two patients with HLH refractory to dexamethasone and etoposide or methylprednisolone and ATG.     

Atypical varicella zoster infection associated with hemophagocytic lymphohistiocytosis

Two adolescents, on immunosuppressive therapy for graft‐versus‐host disease, developed hemophagocytic lymphohistiocytosis (HLH) after varicella zoster virus (VZV) reactivation. In the absence of dermatome restricted characteristic skin lesions, VZV reactivation was not immediately recognized and treatment with acyclovir was delayed. The first patient developed optical neuritis and died 2 months after the VZV episode due to massive intracranial hemorrhage. The second patient presented with severe abdominal pain and pancreatitis, followed by atypical skin eruptions, which prompted a faster diagnosis. Both patients recovered from their HLH, the first patient being successfully treated with immunosuppressive agents and the second with VZV treatment only. These two cases demonstrate the difficulties in recognizing VZV reactivation, and in order to start adequate and timely treatment, the need to consider VZV as a possible cause of HLH in severely immunocompromised patients. Pediatr Blood Cancer 2009;53:226–228. © 2009 Wiley‐Liss, Inc.     

Clinical assessment of Mycoplasma pneumoniae-associated hemophagocytic lymphohistiocytosis

Background: Mycoplasma pneumoniae has been reported to be an etiologic pathogen of infection-associated hemophagocytic lymphohistiocytosis (HLH), but few case reports have been available to date.
Methods: The clinical features of four childhood cases of M. pneumoniae -associated hemophagocytic lymphohistiocytosis (Mp-HLH) were retrospectively assessed to obtain data that might be useful for early diagnosis and effective management. The previous English-language literature pertaining to Mp-HLH was also reviewed.
Results: The patients were two boys and two girls, aged between 1 and 11 years of age. One patient was demonstrated to have concurrent infection with rubella. All the patients had typical radiographic features of M. pneumoniae pneumonia, and one patient also had encephalopathy as a complication. All the children underwent bone marrow examination because of antibiotic-refractory fever, mild hepatosplenomegaly, cytopenia, hyperferritinemia and elevated levels of urine β2-microglobulin. Cytopenia and hepatosplenomegaly in the present patients were relatively mild as compared to those in cases of other infection-associated HLH such as Epstein–Barr virus infection-associated HLH. Treatment with corticosteroids resulted in prompt and complete resolution in two cases, and i.v. high-dose gammaglobulin therapy achieved a complete response in another child. Spontaneous resolution under treatment with antibiotics alone was observed in one case.
Conclusion: Although Mp-HLH is a rare complication of M. pneumoniae infection, it should always be considered in patients with antibiotic-refractory M. pneumoniae infections with cytopenia. Mp-HLH might be effectively treated by corticosteroids or high-dose gammaglobulin. To clarify the diverse clinical manifestations of M. pneumoniae infections, immunological interactions between M. pneumoniae and the host immune system should be further investigated.     

感染相关噬血细胞淋巴组织增生症研究进展

噬血细胞淋巴组织增生症(HLH)是儿童期常见的免疫性疾病之一。细菌、EB病毒、原虫、真菌、衣原体等感染是HLH的常见病因。目前认为感染相关HLH的发病机制是由于NK细胞和细胞毒T细胞(CTL)介导的穿孔素依赖的细胞毒作用缺陷所导致的多系统炎症反应,感染激活巨噬细胞、树突状细胞、NK细胞和CTL,导致细胞因子风暴形成。不同的感染类型可针对其病因控制。研究证实4周内积极应用依托泊苷在内的化疗方案能够改善预后,化疗诱导阶段适当短期应用环孢素A有利于粒细胞减少症恢复。预后不良的因素包括高血清铁蛋白和乳酸脱氢酶、IL-2R和IFN-γ升高,EB病毒感染引起的HLH、年龄过小或年龄>30岁可能增加病死率。     

Familial hemophagocytic lymphohistiocytosis and viral infections

A retrospective study was performed in 32 children with hemophagocytic lymphohistiocytosis, 16 of whom had affected siblings. Altogether 22 of these children, of whom the majority (13/22) were familial cases, had clinical or laboratory signs of infection. Laboratory analysis demonstrated Epstein-Barr virus in five children, cytomegalovirus in three and human parvovirus in two. Two siblings with onset of familial hemophagocytic lymphohistiocytosis within one month of each other, both of whom demonstrated serological indications of a recent human parvoviral infection at onset, are described. It is concluded that a viral infection cannot serve as the sole criterion for distinguishing a virus-associated hemophagocytic syndrome as an entity separate from familial hemophagocytic lymphohistiocytosis. Instead, it is suggested that viral infections may elicit a bout of the familial hemophagocytic lymphohistiocytosis disorder in genetically predisposed individuals.     

Elevated circulating levels of interleukin-1 receptor antagonist but not IL-1 agonists in hemophagocytic lymphohistiocytosis

The familial form of hemophagocytic lymphohistiocytosis (HLH) is an inherited disease with disturbed immunomodulation and characterized by fever, hepatosplenomegaly, cytopenia, hypertriglyceridemia, and coagulopathy, i.e., findings which are similar to many of the reported biological effects of the inflammatory cytokines. Due to the previously shown hypercytokinemia in active HLH with elevated levels of interleukin (IL)-6, tumor necrosis factor-α, and interferon-gamma, it has been suggested that cytokine dysregulation may be of pathophysiological importance. Here we have assayed the serum levels of the members of the IL-1 ligand family, the two agonists IL-1α and IL-1β and the antagonist IL-1 receptor antagonist (IL-1ra), in nine children with HLH and cerebrospinal fluid (CSF) specimens from four children. Serum IL-1ra was elevated in all patients with active disease to a degree which correlated well with disease activity. Furthermore, the levels decreased day by day during treatment of a patient who suffered a relapse. Moreover, high levels of IL-1ra were also detected in CSF during active disease. However, IL-1β levels were all within normal limits and circulating IL-1α levels were normal in all but two patients. © 1996 Wiley-Liss, Inc.     

Challenges in the diagnosis of hemophagocytic lymphohistiocytosis: Recommendations from the North American Consortium for Histiocytosis (NACHO)

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation, often associated with genetic defects of lymphocyte cytotoxicity. Though a distinctive constellation of features has been described for HLH, diagnosis remains challenging as patients have diverse presentations associated with a variety of triggers. We propose two concepts to clarify how HLH is diagnosed and treated: within the broader syndrome of HLH, “HLH disease” should be distinguished from “HLH disease mimics” and HLH subtypes should be categorized by specific etiologic associations, not the ambiguous dichotomy of “primary” and “secondary.” We provide expert‐based advice regarding the diagnosis and initiation of treatment for patients with HLH, rooted in improved understanding of its pathophysiology.     

HLH-2004: Diagnostic and therapeutic guidelines for hemophagocytic lymphohistiocytosis

In HLH-94, the first prospective international treatment study for hemophagocytic lymphohistiocytosis (HLH), diagnosis was based on five criteria (fever, splenomegaly, bicytopenia, hypertriglyceridemia and/or hypofibrinogenemia, and hemophagocytosis). In HLH-2004 three additional criteria are introduced; low/absent NK-cell-activity, hyperferritinemia, and high-soluble interleukin-2-receptor levels. Altogether five of these eight criteria must be fulfilled, unless family history or molecular diagnosis is consistent with HLH. HLH-2004 chemo-immunotherapy includes etoposide, dexamethasone, cyclosporine A upfront and, in selected patients, intrathecal therapy with methotrexate and corticosteroids. Subsequent hematopoietic stem cell transplantation (HSCT) is recommended for patients with familial disease or molecular diagnosis, and patients with severe and persistent, or reactivated, disease. In order to hopefully further improve diagnosis, therapy and biological understanding, participation in HLH studies is encouraged.     

Immunosuppression: Preliminary results of alternative maintenance therapy for familial hemophagocytic lymphohistiocytosis (FHL)

Hemophagocytic lymphohistiocytosis (HLH) describes a group of disorders with similar clinical features that are associated with a very high mortality rate. Patients with HLH, and particularly the infantile form referred to as familial hemophagocytic lymphohistiocytosis (FHL), are often treated with multiple courses of epipodophyllotoxins, such as etoposide, for prolonged periods of time. Because of the concern regarding the risk of epipodophyllotoxin-induced acute myelogenous leukemia (AML) we have explored the use of immunosuppression as maintenance therapy for patients with FHL while they await the only known definitive treatment, i.e., bone marrow transplantation (BMT). We report 2 infants with FHL who had significant central nervous system involvement at diagnosis. Both were initially treated with etoposide, methotrexate, and glucocorticosteroids. Once clinical improvement was achieved these patients were successfully maintained in clinical remission of FHL on daily cyclosporine A (CSA) and glucocorticosteroids along with intermittent intrathecal methotrexate for 5 months until appropriate unrelated donors could be identified for BMT.     

Fatal hemophagocytic lymphohistiocytosis in X‐linked chronic granulomatous disease associated with a perforin gene variant

A patient with previously unrecognized X‐linked chronic granulomatous disease (X‐CGD) died of multi‐organ failure, secondary to ongoing infection and hemophagocytic lymphohistiocytosis (HLH). Post mortem histological investigations were compatible with X‐CGD, and a CYBB gene mutation was confirmed. No homozygous mutations in the genes encoding perforin (PRF1), MUNC 13‐4 or syntaxin‐11 (STX11) were found; however, there was a heterozygous alteration c.1471G>A in the PRF1 gene causing a p.Asp491Asn substitution. Although this substitution has not been reported to cause primary or secondary HLH, we speculate that it may have made the patient more susceptible for HLH under the circumstances of ongoing infection associated with X‐CGD. Pediatr Blood Cancer 2009;52:527–529. © 2008 Wiley‐Liss, Inc.