Diagnostic Criteria For Hemophagocytic Lymphohistiocytosis Research Articles

Abstract 193: Hemophagocytic lymphohistiocytosis following kawasaki disease:Differential Diagnosis in IVIG Refractory Kawasaki Disease

Introduction: Hemophagocytic lymphohistiocytosis(HLH) is a systemic inflammatory disorder characterized by uncontrolled histiocytic proliferation, hemophagocytosis and up-regulation of inflammatory cytokines. Thus, both HLH and Kawasaki disease(KD) are characterized by prolonged fever, and are diagnosed by a clinical and laboratory scoring system, concurrent manifestation of HLH and KD has been described in the literature. We describe two cases of children who diagnosed as KD initially, but after intravenous gamma globulin(IVIG) failed to produce clinical response, were found to have HLH. Case report: A 3-year-old boy who had previous KD history 5 months ago was admitted for 9day fever and skin rash. His symptoms were fulfilled KD criteria, and echocardiography showed dilated right coronary artery of 4.2mm. He was treated with 2 cycles of IVIG until fever subsided. However, 2 days later, he got fever again and cytopenia(Hb<9.0), hypertriglyceridemia, high level of ferritin was shown and had splenomegaly on physical examination. In the suspicion of HLH, bone marrow biopsy was done and revealed hemophagocytosis, consistent with HLH. A second case of 11-month-old boy admitted for 8-day fever with Kawasaki feature. Although, he showed incomplete feature(fever, skin rash, conjunctival injection, cervical lymphadenopathy), echocardiography showed dilated left main coronary artery(3.5mm) and treated with IVIG. However, 2days after IVIG administration, he was still pyrexial. The laboratory findings fulfilled 5 diagnostic criteria of HLH; bicytopenia(anemia, thrombocytopenia), hypofibrinogenemia, hyperferritinemia, hemophagocytosis in bone marrow, raised level of soluble IL-2 receptor. In both cases, the patients treated according to the HLH protocol 2004, and after that clinical symptoms and laboratory findings were improved. Several causes of febrile illness, EBV, CMV, rubella, parvo-viral infection, for example, were excluded. Comment: There is considerable overlap between the clinical syndromes of KD and HLH and early recognition and treatment of these two disease entity is imperative to avoid fatal outcomes in severe cases. Thus, these should both be considered and excluded in any child with unremitting fever and rash.

Ehrlichia-Induced Hemophagocytic Lymphohistiocytosis: A Case Series

Background: Hemophagocytic lymphohistiocytosis (HLH) is a rare potentially fatal hyperinflammatory syndrome. There are familial forms (primary HLH), typically presenting in childhood, and sporadic forms (secondary HLH), often presenting in adults. Many cases of HLH are in response to infectious pathogens. While Epstein Barr virus, HIV, and bacterial infections are the dominant non malignancy related causes linked with HLH, there are scattered case reports of other uncommon pathogens associated with HLH. We describe the clinical and laboratory findings from a series of 5 cases of Ehrlichia-induced HLH.Methods: We have reviewed diagnoses of HLH in adolescents and adults treated at Barnes-Jewish Hospital in St. Louis from June 2001 through June 2014. The diagnosis of Ehrlichia was made by PCR testing on peripheral blood. HLH diagnosis was based on the 2004 Histiocyte Society Criteria for HLH. Five of the following 8 criteria should be met: 1) fever ≥ 38.50C; 2) splenomegaly; 3) cytopenia of two or three lines: ANC < 1 × 103/µL, hemoglobin < 9 g/dL, platelet count < 100 × 103/µL; 4) hypertriglyceridemia ≥ 265 mg/dL or hypofibrinogenemia ≤ 150 mg/dL; 5) hyperferritinemia ≥ 500 µg/L; 6) increased soluble IL-2 receptor ≥ 2,400 U/mL; 7) low/absent natural killer (NK) cell activity; and 8) pathology showing hemophagocytosis (bone marrow, spleen, or lymph nodes).Results: Among 77 confirmed HLH cases, we identified Ehrlichia chaffeensis to be the causative agent of secondary HLH in 5 cases. Table 1 summarizes the initial characteristics of patients. All patients were Caucasian with a median age of 52 years (range, 16-62). Four patients were female and one male. All patients presented during summer time. Four patients reported recent history of tick bites. All patients were febrile on presentation. Hyperferritinemia was striking and median peak ferritin was 10002 µg/L (range, 2863-85517). Bone marrow biopsy was performed on 4 patients, 3 of which showed hemophagocytosis.Two patients had neurologic symptoms and they tested positive for Ehrlichia chaffeensis on cerebrospinal fluid. Doxycycline was administered on day 2, 1, 3, 1, and 1 of admission (respectively for patients 1 through 5). In addition to doxycycline, Patient 1 received rifampin and dexamethasone, Patient 2 received methyprednisolone, and Patients 4 and 5 received dexamethasone. After a median follow up of 7.3 months (range, 1.7-35.8), all patients were alive and none had recurrence of HLH.We identified an additional 4 cases of Ehrlichia infection presenting with fever, cytopenia(s), and high ferritin. These patients fulfilled 4 of the HLH diagnostic criteria. Al patients responded to doxycycline.Conclusion: Ehrlichia can trigger HLH and should be on the differential diagnosis of critically ill patients presenting with fever and hyperferritinemia, especially during warm weather when tick bites are more likely in areas endemic with Ehrlichia. Although HLH is often fatal, the prognosis of Ehrlichia-induced HLH is quite good with early diagnosis and prompt initiation of treatment.Table 1Initial characteristics of patientsCharacteristicPatient 1*Patient 2*Patient 3Patient 4Patient 5Age (years)5247591662GenderFFFFMFeverYYYYYSplenomegalyNNNNYANC (× 103/µL)0.112.10.60.43.9Hemoglobin (g/dL)7.98.610.611.98.8Platelets (× 103/µL)2565413720Triglycerides (mg/dL)650710307319516Fibrinogen (mg/dL)173178N/A187312Ferritin (µg/L)472901000228638551784676Hemophagocytosis^YNYYN/PSoluble IL-2 (U/mL)>65005873N/PN/PN/PLow/absent NK cell activityFailedN/PN/PN/PN/P* CNS involvement with Ehrlichia^ Patients 1, 2, 3 and 4 had bone marrow biopsy. Pathology testing was not performed on lymph node or spleen.Abbreviations: F, female; M, male, Y, yes; N, no; N/P, not performed; ANC, absolute neutrophil count DisclosuresNo relevant conflicts of interest to declare.

ABSTRACT 676

Background and aims: Hemophagocytic Lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation. HLH and sepsis-induced multiple organ failure share similar clinical features and biomarkers. The correct diagnosis is essential for strategizing the management including immune modulation. Ferritin is one of the 8 diagnostic criteria for HLH. Ferritin is made up of 2 types of polypeptide chains, heavy and light. Synthesis of heavy chain ferritin, specifically, is induced by tumor necrosis factor-alpha via the NF-KB pathway. Currently, there is no study on these ferritin subtypes in HLH and sepsis. Aims: The aim of this study is to describe the heavy and light chain ferritins in HLH and septic patients. Methods: Plasma samples of pediatric patients with severe sepsis were collected from a single center, and with HLH from a collaborative multicenter HLH study group. We analyzed light and heavy chain ferritins by using Western blotting, monoclonal antibodies, and radio optical densitometry. Results: We analyzed plasma from 11 severe sepsis and 8 HLH patients. We found the presence of light chain ferritin in the plasma of 2 severe sepsis and 4 HLH patients. We found the presence of heavy chain ferritin in the plasma of all severe sepsis and HLH patients. The concentration of heavy chain ferritin was 3.6 times more in HLH patients compared to severe sepsis patients. Conclusions: Heavy chain ferritin is present in both HLH and severe sepsis patients. Heavy chain ferritin seems to be more elevated in patients with HLH compared to severe sepsis. More studies are warranted.

Flow cytometry in the diagnosis of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis is a multisystem inflammation, generated by the uncontrolled and excessive activation of cytotoxic T lymphocytes and natural killer cells. Severe immunodeficiency and generalized macrophage activation can often be detected in the background of this life threatening disorder. It is classified as a primary immunodeficiency. Functional abnormalities of the perforin protein or defects in granule secretory mechanisms are caused by gene mutations in most cases. Diagnostic criteria of hemophagocytic lymphohistiocytosis are the following: fever, splenomegaly, cytopenias affecting at least two of the 3 lineages in peripheral blood, hypertriglyceridemia and hyperferritinemia, elevated serum level of soluble interleukin-2 receptor (sCD25), hypofibrinogenemia, hemophagocytosis in bone marrow and decreased cytotoxic T cell and natural killer cell activity. In this case report the authors summarize the utility of functional flow cytometry in the diagnosis of hemophagocytic lymphohistiocytosis. Using flow cytometry, elevated intracellular perforin content, decreased killing activity of cytotoxic T cells and natural killer cells, and impaired cell surface expression of CD107a (LAMP1 protein) from in vitro stimulated blood lymphocytes were detected. Abnormal secretion of perforin was also demonstrated. Genetic testing revealed mutation of the MUNC 13-4 gene, which confirmed the base of the abnormal flow cytometric findings. This case report demonstrates the value of functional flow cytometry in the rapid diagnosis of genetically determined hemophagocytic lymphohistiocytosis, a condition in which early diagnosis is critical for optimal management. The authors emphasize the significance of functional flow cytometry in the differential diagnosis of immunodeficiencies. Orv. Hetil., 2014, 155(10), 389–395.

Hemophagocytosis on bone marrow aspirate cytology: single center experience in north himalayan region of India.

Background:The differentiation of hemophagocytic lymphohistiocytosis (HLH) with other causes of hemophagocytosis is essential as HLH is life-threatening condition and requires definite clinical and biochemical criteria for its diagnosis.Aim:The present study was conducted to study hemophagocytosis on bone marrow aspirates and to observe if there is any difference on bone marrow examination between HLH and non HLH cases showing hemophagocytosis.Materials and Methods:The study reviewed all the cases of bone marrow aspirate for evidence of hemophagocytosis in which at least three smears and 500 nucleated cells were observed for every case. The cases were provisionally diagnosed as HLH according to the proposed HLH diagnostic criteria, 2009.Results:A total of 80 cases showed hemophagocytosis in the present study with infections followed by HLH being the most common cause. Pancytopenia and erythroid hyperplasis were common hematological presentation. Moderate to severe hemophagocytosis was observed in HLH cases while mild grade in non HLH cases.Conclusion:The study concludes that hemophagocytosis even if observed in single cell should always be documented in the bone marrow reports. It may be the only indicator of subtle infection in the marrow. Pancytopenia and higher grade of hemophagocytosis on bone marrow examination may be helpful in establishing an early differentiation of HLH and non HLH cases.

Hemophagocytic Lymphohistiocytosis Complicating T-Cell Lymphoma in a Patient with HIV Infection

Hemophagocytic lymphohistiocytosis (HLH), while uncommon, may be a devastating complication of lymphoma and/or human immunodeficiency virus (HIV) infection. While several of the diagnostic criteria for HLH are relatively nonspecific, particularly in the setting of a systemic inflammatory response, more diagnostic specificity may be achieved with marked elevations in serum ferritin (e.g., >100,000 ng/mL). Increased suspicion of HLH, particularly in the setting of persistent, unexplained fevers, pancytopenia, and transaminitis, should prompt consideration of HLH. Earlier diagnosis and initiation of therapy have the potential to alter the natural history and poor prognosis of this disorder. We present a patient with HIV infection who developed relapsed T-cell lymphoma complicated by hemophagocytic lymphohistiocytosis.

Haemophagocytic lymphohistiocytosis following culture-proven pneumococcal infective endocarditis of the tricuspid valve

We report a case of a 2-year-old boy presenting with persistent fever and splenomegaly who fulfilled the diagnostic criteria for haemophagocytic lymphohistiocytosis (HLH) according to the Histiocyte Society (2004). The persistence of a cardiac murmur despite multiple transfusions, and therapy which rendered him afebrile, led us to do an echocardiogram as part of surveillance for sepsis. This revealed tricuspid vegetation and a small ventricular septal defect. Blood culture and postoperative histology of the anterior leaflet of the tricuspid valve confirmed Streptococcus pneumoniae infection. The patient was successfully treated with intravenous antibiotic therapy for 6 weeks and dexamethasone for 8 weeks and remains well and in remission (from HLH) a year later with residual tricuspid regurgitation awaiting tricuspid valve replacement.

Specificity of cytokine abnormalities in HLH

Hemophagocytic lymphohistiocytosis (HLH) is both under-recognized and over-diagnosed currently. Despite the use of the revised criteria for diagnosis, established by the Histiocyte Society in 2004, it seems that patients with severe infections, as well as patients with severe underlying rheumatologic and oncologic conditions receiving modern therapies (in whom HLH, or macrophage activation syndrome, can indeed occur), can meet criteria without a convincing “fit” for the clinician (Pediatr Blood Cancer 2007;48:124-31). On the other hand, especially early in the course in previously healthy younger children, HLH sometimes seems to be the “best diagnosis” even though laboratory criteria are not met fully. Accuracy of diagnosis is critical because therapy for HLH is either extremely helpful in abrogating an abnormal inflammatory response if the diagnosis is correct, or extremely harmful in impeding an appropriate response if the diagnosis is incorrect, especially when infection is the sole or predominant pathology.In a particularly robust study, Xu et al evaluated 756 consecutive patients with fever hospitalized in the Hematology/Oncology Unit of the Children's Hospital of Zhejiang University School of Medicine between 2005 and 2010, categorized the etiologies of fever, and also studied three control groups of 202 patients with hematology/oncology conditions without fever, 100 healthy children, and 85 previously healthy children with confirmed bacterial sepsis. Multiplex Th1/Th2 cytokine kit assay was used to measure serum concentrations of defined interleukins (IL), tumor necrosis factors, and interferon.The 71 episodes of HLH showed a highly discriminating cytokine pattern of uniquely highly elevated IFN-γ level (94% sensitivity and 97% specificity for HLH using a cutoff point of 100 pg/mL) and IL-10 level, but only modestly elevated IL-6 level. Combined use of IFN-γ level >75 pg/mL plus IL-10 >60 pg/mL had sensitivity of 93% and specificity of 99% for HLH.The authors point out limitations of the study, as well as the heterogeneity of HLH itself, which probably encompasses multiple disorders, with a variety of etiologies and triggers, and a spectrum of severity. There is no question, however, that these results can help clinicians having to make weighty decisions and, with validation, can be considered by consensus groups for inclusion in diagnostic criteria for HLH.Article page 984▶ Hemophagocytic lymphohistiocytosis (HLH) is both under-recognized and over-diagnosed currently. Despite the use of the revised criteria for diagnosis, established by the Histiocyte Society in 2004, it seems that patients with severe infections, as well as patients with severe underlying rheumatologic and oncologic conditions receiving modern therapies (in whom HLH, or macrophage activation syndrome, can indeed occur), can meet criteria without a convincing “fit” for the clinician (Pediatr Blood Cancer 2007;48:124-31). On the other hand, especially early in the course in previously healthy younger children, HLH sometimes seems to be the “best diagnosis” even though laboratory criteria are not met fully. Accuracy of diagnosis is critical because therapy for HLH is either extremely helpful in abrogating an abnormal inflammatory response if the diagnosis is correct, or extremely harmful in impeding an appropriate response if the diagnosis is incorrect, especially when infection is the sole or predominant pathology. In a particularly robust study, Xu et al evaluated 756 consecutive patients with fever hospitalized in the Hematology/Oncology Unit of the Children's Hospital of Zhejiang University School of Medicine between 2005 and 2010, categorized the etiologies of fever, and also studied three control groups of 202 patients with hematology/oncology conditions without fever, 100 healthy children, and 85 previously healthy children with confirmed bacterial sepsis. Multiplex Th1/Th2 cytokine kit assay was used to measure serum concentrations of defined interleukins (IL), tumor necrosis factors, and interferon. The 71 episodes of HLH showed a highly discriminating cytokine pattern of uniquely highly elevated IFN-γ level (94% sensitivity and 97% specificity for HLH using a cutoff point of 100 pg/mL) and IL-10 level, but only modestly elevated IL-6 level. Combined use of IFN-γ level >75 pg/mL plus IL-10 >60 pg/mL had sensitivity of 93% and specificity of 99% for HLH. The authors point out limitations of the study, as well as the heterogeneity of HLH itself, which probably encompasses multiple disorders, with a variety of etiologies and triggers, and a spectrum of severity. There is no question, however, that these results can help clinicians having to make weighty decisions and, with validation, can be considered by consensus groups for inclusion in diagnostic criteria for HLH. Article page 984▶ Diagnostic Accuracy of a Specific Cytokine Pattern in Hemophagocytic Lymphohistiocytosis in ChildrenThe Journal of PediatricsVol. 160Issue 6PreviewThe study goal was to determine the diagnostic accuracy of a specific cytokine pattern including interferon-gamma (IFN-γ), interleukin (IL)-10, and IL-6 for hemophagocytic lymphohistiocytosis (HLH) in febrile children. Full-Text PDF

Novel mutation in STXBP2 prevents IL-2–induced natural killer cell cytotoxicity

We have identified dizygotic twins with a novel syntaxin-binding protein 2 (STXBP2) mutation, where cytotoxicity cannot be restored with IL-2. This defines STXBP2 as an absolute requirement for NK cell cytotoxic function.

Establishment of a reference interval for natural killer cell activity through flow cytometry and its clinical application in the diagnosis of hemophagocytic lymphohistiocytosis

Recently, the Histiocyte Society revised the diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH) to include low or absent natural killer (NK) cell activity, according to local laboratory reference. The aim of this study was to establish reference interval for functional NK-cell activity in 63 healthy Korean individuals using a flow-cytometric assay. We used peripheral blood mononuclear cells (PBMCs) as effector cells and Fluorescein isothiocyanate-labeled K562 cells as target cells. NK-cell activity was calculated using the following equation: NK-cell activity (%) = (test lysis - spontaneous lysis) x 100/(maximum lysis - spontaneous lysis). NK-cell activity was analyzed in 13 known HLH patients and 16 suspected non-HLH patients using a flow-cytometric assay. The mean (+/-SD) cytotoxicity of PBMCs from healthy individuals was 20.9 +/- 5.3% and the reference interval was 11.8-31.9%. The mean NK-cell activity of HLH patients (8.3 +/- 8.9%) was significantly lower (P = 0.001) than that of non-HLH patients (20.1 +/- 7.8%). The sequential changes in NK-cell activity in the HLH group corresponded to clinical and laboratory findings following treatment. We successfully developed a functional NK-cell activity test for use in the clinical laboratory and obtained a reference interval of NK-cell activity from healthy donors. This assay, and associated reference interval, was used to analyze 30 clinically relevant specimens and the results were shown to be well correlated.

Kawasaki disease preceding haemophagocytic lymphohistiocytosis: Challenges for developing world practitioners

Kawasaki disease (KD) is a recognised precipitant of haemophagocytic lymphohistiocytosis (HLH). Although KD has been previously described in the developing world, there are no reported cases of KD preceding HLH. We report a case of a child with a persistent rash and unremitting fever consistent with the diagnosis of KD, who was found to have HLH, after intravenous gamma globulin failed to produce a clinical response. The diagnosis was made using the revised diagnostic criteria for HLH from the Histiocyte Society (1994). She fulfilled six of the eight clinical and laboratory criteria needed to make the diagnosis.

Diagnostic challenges in a child with familial hemophagocytic lymphohistiocytosis type 3 (FHLH3) presenting with fulminant neurological disease

Familial hemophagocytic lymphohistiocytosis (FHLH) is an autosomal recessively inherited multisystem disease characterized by fever, rash, splenomegaly, cytopenias, and variable central nervous system (CNS) manifestations. We report the case of a 3-year-old boy who presented with splenomegaly and normocytic anemia 4 months after returning to the US from a region endemic for Leishmania infection. The child later developed progressive neurological impairment and had radiologic evidence of widespread demyelinating disease. Gene studies showed homozygosity for a mutation at Munc13-4, confirming FHLH type 3. The diagnostic uncertainty that accompanies FHLH was compounded by our patient's travel history and CNS disease mimicking acute disseminated encephalomyelitis (ADEM). Diagnostic criteria for hemophagocytic lymphohistiocytosis were not consistently met, despite aggressive disease. FHLH may present with fulminant demyelinating disease, mimicking ADEM, and without necessarily meeting previously defined clinical and laboratory criteria. We strongly recommend expeditious molecular testing and genetic counseling for FHLH mutations in cases of undiagnosed inflammatory CNS disease in the pediatric population.

The Outcome of 129 Korean Children with Hemophagocytic Lymphohistiocytosis.

Chemotherapy and immunotherapy based treatments improved survival of patients with hemophagocytic lymphohistiocytosis(HLH), but the outcome is still unsatisfactory. We analyzed the putative prognostic factors in a nationwide cohort of patients with HLH. Retrospective data recruitment for the patients diagnosed as HLH during the past 10-year period from 1996 to 2005 was carried out by the Histiocytosis Working Party of the Korean Society of Hematology. The HLH diagnostic criteria of the Histiocyte Society were strictly applied to confirm the eligibility of patients for this study. We analyzed the outcome of pediatric patients with HLH according to the age at diagnosis, sex, central nervous system(CNS) involvement, disease condition(familial or secondary), treatment modalities and disease state after 2 months of initial treatment. One hundred twenty nine patients from 19 centers fulfilled the diagnostic criteria(n=112) and/or had affected siblings together with some of the criteria(n=17). The male to female ratio was 0.95:1. The probability of 3 year overall survival(OS) in HLH patients was 41% with a median follow-up of 51 months. The 3 year OS in patients under 12 months of age at presentation(n=23) was 21.7%, and 44.3% in those over 12 months of age(n=106)(p=0.001). The 3 year OS in patients with CNS involvement(n=16) was 29.1%, and 44.4% in patients without CNS involvement(n=112)(p=0.01). The 3 year OS in patients with active state after 2 months of initial treatment(n=63) was 14.1% compared to 77.2% in those with inactive state(n=61)(p=0.0001). The 3 year OS in patients who received hematopoietic stem cell transplantation(HSCT)(n=17) was 82.3%, and 35.2% in patients treated with chemoimmunotherapy only(n=112)(p=0.03). Among the HSCT patients, complete remission was obtained in 14 patients except 3 other patients who died of infection and graft failure at early post-transplant period. The reasons for HSCT were active disease after chemoimmunotherapy(n=8), relapsed disease(n=5), and familial HLH(n=4). Other prognostic factors were not significantly correlated with outcome in our survey. The age and CNS involvement at diagnosis, disease state after 2 months of initial treatment were important prognostic factors which affected the outcome of HLH significantly in this cohort. This survey also demonstrated excellent outcome of familial or relapsed, persistent secondary HLH after HSCT compared to chemoimmunotherapy only.

Intermittent hemophagocytic lymphohistiocytosis is a regular feature of lysinuric protein intolerance

We describe 4 cases of lysinuric protein intolerance, which all fulfilled the diagnostic criteria for hemophagocytic lymphohistiocytosis. Mature histiocytes and neutrophil precursors participated in hemophagocytosis in the bone marrow. Moreover, serum levels of ferritin and lactate dehydrogenase were elevated, hypercytokinemia was present, and soluble interleukin-2 receptor levels were increased up to 18.6-fold. The diagnosis of lysinuric protein intolerance should therefore be considered in any patient presenting with hemophagocytic lymphohistiocytosis. (J Pediatr 1999;134:236-9)