Hemophagocytic syndromes (HPSs) including hemophagocytic lymphohistiocytosis (HLH) in adults: A systematic scoping review

Clinical characteristics, therapy response, and outcome of 51 adult patients with hematological malignancy-associated hemophagocytic lymphohistiocytosis: a single institution experience

Hemophagocytic lymphohistiocytosis (HLH) is an underdiagnosed but life-threatening syndrome of hyperinflammation often occurring in adults with hematological malignancies (hM-HLH). The aim of the study was to describe clinical characteristics, therapy response, and outcome of adults with hM-HLH. The study included 51 adults with hM-HLH aged 23-84 years. Hyperferritinemia ≥500 µg/L was present in 96% of patients. The serum concentration of sIL-2Rα ≥ 2400 U/mL was revealed in 94% of patients. Twenty-three patients (45%) responded to therapy and achieved remission of HLH. The probability of overall survival (OS) at 6, 12, 24, and 60 months after HLH diagnosis were 42, 20, 15, and 15%, respectively. Patients with HLH during chemotherapy showed longer OS (median 124 days) than the patients who had HLH solely attributed to malignancy (median 65 days), but this difference was not statistically significant. Awareness of HLH in lymphoid and myeloid malignancies is crucial for improved survival.

Clinical features and outcomes in secondary adult hemophagocytic lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome characterized by an infrequent but immune-mediated life-threatening disease, with confusing clinical manifestations, rapidly deteriorating health, high morbidity and mortality and challenging diagnosis.

AIM

The purpose of this study was to improve the recognition and understanding of HLH.

DESIGN

Retrospective observational cross-sectional study.

METHODS

Data were collected for all cases of adult patients diagnosed with HLH in a large cohort managed at a single medical center from January 2011 to December 2015.

RESULTS

The median age was 52 years (range 18-90 years) and 123 (60.0%) were male. Over 95% patients manifested fever, hyperferritinemia and elevated lactate dehydrogenase. Underlying triggers of HLH were as follows: 119 (58.0%) malignancies, 83 (40.5%) infections, 14 (6.8%) unknown triggers and 14 (6.8%) autoimmune disorders. The median overall survival was 55 days. And elderly patients (age ≥60 years) had a markedly worse survival compared with young patients (age <60 years) (median overall survival 24 days vs. 159 days, respectively; P <0.001). In a multivariable analysis, platelet <40 × 109/l (HR = 2.534; 95% CI 1.152-5.573; P = 0.021), PT prolonged >3 s (HR = 1.909; 95% CI 1.127-3.234; P = 0.016) and malignancy (HR = 1.614; 95% CI 1.008-2.582; P = 0.046) were correlated with poor survival.

CONCLUSION

HLH adult patients had very complex clinical manifestations as well as underlying diseases. Patients with PLT <40 ×109/l, PT prolonged >3 s and malignancy had inferior survival. It is of great importance to improve our understanding of this syndrome.

Soluble interleukin-2 receptor is a sensitive diagnostic test in adult HLH

Serum soluble interleukin-2 receptor (sIL-2r) is an important disease marker in hemophagocytic lymphohistiocytosis (HLH), but there are no published data on its diagnostic value in adults. We conducted a single-center retrospective study of 78 consecutive adults who had sIL-2r measured for suspected HLH. Serum sIL-2r levels were measured by enzyme-linked immunosorbent assay (adult reference range, 241-846 U/mL). There were 38 patients with HLH and 40 with a non-HLH diagnosis (such as sepsis, liver disease, histiocyte disorders, autoimmune disease, leukemia, or lymphoma). The receiver operating characteristic curve demonstrated that sIL-2r is a good to excellent diagnostic test for adult HLH, with an area under the curve (AUC) of 0.90 (95% confidence interval, 0.83-0.97) compared with AUC 0.78 (95% confidence interval, 0.67-0.88) for ferritin. The optimal threshold for sIL-2r was 2515 U/mL (sensitivity, 100%; specificity, 72.5%). Although there was a large indeterminate range for sIL-2r, a level of 2400 U/mL or less was helpful for ruling out HLH (sensitivity, 100%), and more than 10 000 U/mL was helpful for ruling in HLH (specificity, 93%). Higher mean sIL-2r levels were seen in malignancy-associated HLH (20 241 U/mL) compared with infection-associated HLH and macrophage activation syndrome (9720 and 5008 U/mL, respectively; P < .05). Levels above 10 000 U/mL were not associated with worse prognosis in patients with HLH. Serum sIL-2r is a sensitive test for diagnosis of adult HLH, but is not as specific as previously reported in children. Additional studies enriched with patients without HLH who have conditions associated with T-cell activation, such as lymphoma and autoimmune lymphoproliferative syndrome, are needed.

Safe usage of anakinra and dexamethasone to treat refractory hemophagocytic lymphohistiocytosis secondary to acute disseminated histoplasmosis in a patient with HIV/AIDS

Hemophagocytic lymphohistiocytosis (HLH) is a serious life-threatening disease if not recognised early. In patients with HIV/AIDS, this association has been reported following acute opportunistic infections, including histoplasmosis. However, optimal treatment is not known. We describe a male aged 46 years with AIDS who developed HLH following acute disseminated histoplasmosis. Presenting symptoms included fever, hepatosplenomegaly and pancytopenia. Bone marrow biopsy confirmed HLH. Initially, he was refractory to the treatment with amphotericin B, antiretroviral therapy and intravenous immunoglobulin (IVIG). Anakinra, an interleukin-1 receptor antagonist, and dexamethasone were initiated. He improved clinically, did not exhibit any harmful effects and ultimately was discharged from the hospital. This, we believe, is the first reported treatment of HLH with anakinra in a patient with AIDS and acute disseminated histoplasmosis.

Development and Initial Validation of the Macrophage Activation Syndrome/Primary Hemophagocytic Lymphohistiocytosis Score, a Diagnostic Tool that Differentiates Primary Hemophagocytic Lymphohistiocytosis from Macrophage Activation Syndrome

OBJECTIVE

To develop and validate a diagnostic score that assists in discriminating primary hemophagocytic lymphohistiocytosis (pHLH) from macrophage activation syndrome (MAS) related to systemic juvenile idiopathic arthritis.

STUDY DESIGN

The clinical, laboratory, and histopathologic features of 362 patients with MAS and 258 patients with pHLH were collected in a multinational collaborative study. Eighty percent of the population was assessed to develop the score and the remaining 20% constituted the validation sample. Variables that entered the best fitted model of logistic regression were assigned a score, based on their statistical weight. The MAS/HLH (MH) score was made up with the individual scores of selected variables. The cutoff in the MH score that discriminated pHLH from MAS best was calculated by means of receiver operating characteristic curve analysis. Score performance was examined in both developmental and validation samples.

RESULTS

Six variables composed the MH score: age at onset, neutrophil count, fibrinogen, splenomegaly, platelet count, and hemoglobin. The MH score ranged from 0 to 123, and its median value was 97 (1st-3rd quartile 75-123) and 12 (1st-3rd quartile 11-34) in pHLH and MAS, respectively. The probability of a diagnosis of pHLH ranged from <1% for a score of <11 to >99% for a score of  ≥123. A cutoff value of ≥60 revealed the best performance in discriminating pHLH from MAS.

CONCLUSION

The MH score is a powerful tool that may aid practitioners to identify patients who are more likely to have pHLH and, thus, could be prioritized for functional and genetic testing.

The emerging role of anti-CD25 directed therapies as both immune modulators and targeted agents in cancer

CD25 (also termed IL2RA) forms one component of the high-affinity heterotrimeric interleukin 2 (IL2) receptor on activated T cells. Its affinity for IL2 and cellular function are tightly regulated and vary in different cell types. The high frequency of CD25 on the surface of many different haematological tumour cells is now well established and, apart from its prognostic significance, CD25 may be present on leukaemic stem cells and enable oncogenic signalling pathways in leukaemic cells. Additionally, high CD25 expression in activated circulating immune cells and Tregs is a factor that has already been exploited by IL2 immunotherapies for treatment of tumours and autoimmune disease. The relative clinical safety and efficacy of administering anti-CD25 radioimmunoconjugates and immunotoxins in various haematological tumour indications has been established and clinical trials of a novel CD25-directed antibody drug conjugate are underway.

Hemophagocytosis lymphocytosis presenting as pulmonary-renal syndrome: a case report and literature review

Hemophagocytosis Lymphocytosis (HLH) is a rare and life-threatening illness that is more commonly seen in infants; however, its incidence in adults is becoming more common. Recognizing HLH in a complicated clinical scenario is key to early recognition, treatment, as well as improved morbidity and mortality.

Clinical utility of soluble interleukin-2 receptor in hemophagocytic syndromes: a systematic scoping review

The serum-soluble interleukin-2 receptor (sIL-2r) level is considered an important diagnostic test and disease marker in hemophagocytic syndromes/hemophagocytic lymphohistiocytosis (HPS/HLH). However, this cytokine receptor is rarely measured in clinical practice and has been excluded from recent diagnostic/classification criteria such as the HScore and macrophage activation syndrome (MAS) 16. We performed a systematic scoping review of 64 articles (1975-2016) examining the clinical utility of sIL-2r in HPS/HLH. Twenty-two articles describe sIL-2r as a sensitive diagnostic marker for HLH, but only three distinct datasets actually address sensitivity. The original HLH-2004 Guidelines reported sensitivity of 93% and specificity of 100% for sIL-2r ≥ 2400, based on a pediatric dataset (n = 152) which is published for the first time in this review. Two pediatric studies reported sensitivity of 89% for sIL-2r ≥ 2400 in diagnosis of MAS complicating juvenile idiopathic arthritis (JIA) (n = 27) and 88% for secondary HLH in acute liver failure (n = 9). Twenty articles described sIL-2r as a dynamic marker of disease activity that falls with response to treatment, and 15 described high initial sIL-2r levels >10,000 U/mL as a poor prognostic marker. The ability of sIL-2r to distinguish between subtypes of HPS/HLH was inconsistent. This review confirms the importance of soluble IL-2r as a diagnostic and disease marker in HPS/HLH, but also reveals the need for more primary data about its performance characteristics, particularly in adults. More emphasis should be made in including this simple, inexpensive test in clinical practice and studies of HPS/HLH.

Interleukin 1 Receptor Antagonist Anakinra, Intravenous Immunoglobulin, and Corticosteroids in the Management of Critically Ill Adult Patients With Hemophagocytic Lymphohistiocytosis

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) causes multiple organ dysfunction frequently leading to intensive care unit (ICU) referral and/or death. We report on a series of critically ill adult patients treated with a non-etoposide-based regimen including interleukin 1 antagonist anakinra, intravenous immunoglobulin (IVIG), and/or corticosteroids (CS) for HLH.

METHODS

Eight adult (≥18 years) ICU patients having received treatment with anakinra ± IVIG ± CS for HLH between March 2014 and March 2016 at a large tertiary care university hospital (Medical University of Vienna, Vienna, Austria) were retrospectively analyzed.

RESULTS

Eight patients (median age: 38 years; range: 20-58 years; 4 males and 4 females) received anakinra together with IVIG (n = 7) and/or high-dose CS (n = 5) for suspected reactive HLH (median H-score: 214; range: 171-288). Seven (88%) patients required vasopressors and invasive mechanical ventilation and 6 (75%) patients required renal replacement therapy (median Sequential Organ Failure Assessment [SOFA] score at HLH diagnosis: 9.5; range: 6-14). Six patients showed a significant decline in the SOFA score at 1 and 2 weeks following treatment initiation (P = .03), and the remainder 2 patients experienced early death. Five patients survived to ICU discharge, 4 of them could further be discharged from hospital (hospital survival rate: 50%). No overt treatment-related toxicity was noted.

CONCLUSION

Anakinra in combination with IVIG and/or CS resulted in a hospital survival rate of 50% in 8 critically ill adult patients with HLH despite a vast degree of organ dysfunction and the need for aggressive ICU treatment. Further research on non-etoposide-based treatment strategies for HLH in critically ill adults is warranted.

Proliferation through activation: hemophagocytic lymphohistiocytosis in hematologic malignancy

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of cytokine-driven immune activation. Cardinal features include fever, hemophagocytosis, hepatosplenomegaly, lymphocytic infiltration, and hypercytokinemia that result in multisystem organ dysfunction and failure. Familial HLH is genetically driven, whereas secondary HLH (SHL) is caused by drugs, autoimmune disease, infection, or cancer. SHL is associated with worse outcomes, with a median overall survival typically of less than 1 year. This reflects difficulty in both diagnostic accuracy and in establishing reliable treatments, especially in cases of malignancy-induced SHL, which have significantly worse outcomes. Malignancy-induced HLH is seen almost exclusively with hematologic malignancies, constituting 97% of cases in the literature over the past 2 years. In these situations, the native immune response driven by CD8 T cells produces an overabundance of T helper 1 cytokines, notably interferon-γ, tumor necrosis factor-α, and interleukin-6, which establish a positive feedback loop of inflammation, enhancing replication of hematologic malignancies while leaving the host immune system in disarray. In this paper, we present 2 case studies of secondary HLH driven by HM, followed by a review of the literature discussing the cytokines driving HLH, diagnostic criteria, and current treatments used or undergoing investigation.

A case report of novel mutation in PRF1 gene, which causes familial autosomal recessive hemophagocytic lymphohistiocytosis

Background

Hemophagocytic Lymphohistiocytosis (HLH) is a life-threatening immunodeficiency and multi-organ disease that affects people of all ages and ethnic groups. Common symptoms and signs of this disease are high fever, hepatosplenomegaly, and cytopenias. Familial form of HLH disease, which is an autosomal recessive hematological disorder is due to disease-causing mutations in several genes essential for NK and T-cell granule-mediated cytotoxic function. For an effective cytotoxic response from cytotoxic T lymphocyte or NK cell encountering an infected cell or tumor cell, different processes are required, including trafficking, docking, priming, membrane fusion, and entry of cytotoxic granules into the target cell leading to apoptosis. Therefore, genes involved in these steps play important roles in the pathogenesis of HLH disease which include PRF1, UNC13D (MUNC13-4), STX11, and STXBP2 (MUNC18-2).

Case presentation

Here, we report a novel missense mutation in an 8-year-old boy suffered from hepatosplenomegaly, hepatitis, epilepsy and pancytopenia. The patient was born to a first-cousin parents with no previous documented disease in his parents. To identify mutated gene in the proband, Whole Exome Sequencing (WES) utilizing next generation sequencing was used on an Illumina HiSeq 2000 platform on DNA sample from the patient. Results showed a novel deleterious homozygous missense mutation in PRF1 gene (NM_001083116: exon3: c. 1120 T > G, p.W374G) in the patient and then using Sanger sequencing it was confirmed in the proband and his parents. Since his parents were heterozygous for the identified mutation, autosomal recessive pattern of inheritance was confirmed in the family.

Conclusions

Our study identified a rare new pathogenic missense mutation in PRF1 gene in patient with HLH disease and it is the first report of mutation in PRF1 in Iranian patients with this disease.

Secondary hemophagocytic lymphohistiocytosis in the setting of metastatic renal cell carcinoma: a case report

Background

Hemophagocytic lymphohistiocytosis is a disease process characterized by unregulated hyperactivation of the immune system associated with multiorgan involvement and high mortality rates. Early recognition is crucial and a recently validated diagnostic schema, the H-Score, may facilitate diagnosis particularly in secondary hemophagocytic lymphohistiocytosis cases. We present a patient with secondary hemophagocytic lymphohistiocytosis in association with metastatic renal cell carcinoma in whom high-dose steroid therapy induced a remarkable response.

Case presentation

A 35-year-old Vietnamese man with quiescent systemic lupus erythematosus was diagnosed 5 months prior to admission with left-sided renal cell carcinoma metastatic to the pancreas and spine. Ten days prior to admission, a febrile illness (temperatures to 39 °C) associated with flu-like symptoms unresponsive to levofloxacin developed. He took only two doses of pazopanib prior to admission. High fevers unresponsive to antimicrobial therapy, cytopenias, disseminated intravascular coagulation, and progressive multiorgan failure led to intubation and intensive care unit stay. Extensive infectious disease workup showed only negative results, but elevation of interleukin-2 receptor, exceedingly high ferritin levels and other features earned an H-Score of 302, consistent with >99% diagnostic probability for secondary hemophagocytic lymphohistiocytosis. High-dose steroid therapy produced a rapid clinical and biochemical response.

Conclusions

Hemophagocytic lymphohistiocytosis is a life-threatening disorder which is likely to be under-recognized. Increased awareness of this disease entity and its diagnosis is crucial toward early recognition and treatment. To our knowledge, our patient is only the second reported with secondary hemophagocytic lymphohistiocytosis occurring in the setting of renal cell carcinoma.

From the Cradle to the Grave: The Role of Macrophages in Erythropoiesis and Erythrophagocytosis

Erythropoiesis is a highly regulated process where sequential events ensure the proper differentiation of hematopoietic stem cells into, ultimately, red blood cells (RBCs). Macrophages in the bone marrow play an important role in hematopoiesis by providing signals that induce differentiation and proliferation of the earliest committed erythroid progenitors. Subsequent differentiation toward the erythroblast stage is accompanied by the formation of so-called erythroblastic islands where a central macrophage provides further cues to induce erythroblast differentiation, expansion, and hemoglobinization. Finally, erythroblasts extrude their nuclei that are phagocytosed by macrophages whereas the reticulocytes are released into the circulation. While in circulation, RBCs slowly accumulate damage that is repaired by macrophages of the spleen. Finally, after 120 days of circulation, senescent RBCs are removed from the circulation by splenic and liver macrophages. Macrophages are thus important for RBCs throughout their lifespan. Finally, in a range of diseases, the delicate interplay between macrophages and both developing and mature RBCs is disturbed. Here, we review the current knowledge on the contribution of macrophages to erythropoiesis and erythrophagocytosis in health and disease.

The Maze of Diagnosing Hemophagocytic Lymphohistiocytosis: Single-Center Experience of a Series of 6 Clinical Cases

Clinical symptoms of hemophagocytic lymphohistiocytosis (HLH) are based on an excessive inflammatory response. Not only the diversity of the putative underlying etiologies of this rare syndrome but also the subsequent large variety of symptoms complicate the diagnosis of HLH in adult patients. However, early diagnosis and immediate treatment initiation are imperative for clinical outcome. In this article, we will review the diagnostic criteria of HLH and, in this context, discuss 6 cases, each of whom presented with a different clinical appearance causally associated with distinct malignant and nonmalignant diseases, exemplifying the spectrum of associations and manifestations of HLH.

Acute liver failure caused by hemophagocytic lymphohistiocytosis in adults: A case report and review of the literature

BACKGROUND

Hemophagocytic lymphohistiocytosis (HLH) is a rare condition that can be caused by a primary or acquired disorder of uncontrolled immune response. Liver injury is a common complication of HLH; however, HLH presenting as acute liver failure (ALF) has rarely been reported in adults.

CASE SUMMARY

A 34-year-old man was admitted to our hospital with nausea and fatigue persisting for 2 weeks and jaundice for 1 week. He had hyperthermia at the onset of disease. At admission, he had severe liver injury with unknown etiology. The laboratory data showed that he had hyperferritinemia, thrombocytopenia, anemia, hypertriglyceridemia, and hypofibrinogenemia. Finally, a bone marrow biopsy revealed hemophagocytic cells, and he was diagnosed with HLH. The patient was treated with prednisone and plasma exchange. However, the liver function of the patient deteriorated, and he finally died of multiorgan failure.

CONCLUSIONS

Reports of adult patients with ALF caused by HLH have increased, and HLH should be suspected in patients with ALF of indeterminate cause. Although the efficacy of the treatment strategy recommended by the HLH 2004 remains to be confirmed in adult patients with ALF caused by HLH, early diagnosis and prompt combined treatment with steroids and cyclosporin A or etoposide should be emphasized.

F4/80+ Host Macrophages Are a Barrier to Murine Embryonic Stem Cell-Derived Hematopoietic Progenitor Engraftment In Vivo

Understanding how embryonic stem cells and their derivatives interact with the adult host immune system is critical to developing their therapeutic potential. Murine embryonic stem cell-derived hematopoietic progenitors (ESHPs) were generated via coculture with the bone marrow stromal cell line, OP9, and then transplanted into NOD.SCID.Common Gamma Chain (NSG) knockout mice, which lack B, T, and natural killer cells. Compared to control mice transplanted with adult lineage-negative bone marrow (Lin⁻ BM) progenitors, ESHP-transplanted mice attained a low but significant level of donor hematopoietic chimerism. Based on our previous studies, we hypothesized that macrophages might contribute to the low engraftment of ESHPs in vivo. Enlarged spleens were observed in ESHP-transplanted mice and found to contain higher numbers of host F4/80⁺ macrophages compared to BM-transplanted controls. In vivo depletion of host macrophages using clodronate-loaded liposomes improved the ESHP-derived hematopoietic chimerism in the spleen but not in the BM. F4/80⁺ macrophages demonstrated a striking propensity to phagocytose ESHP targets in vitro. Taken together, these results suggest that macrophages are a barrier to both syngeneic and allogeneic ESHP engraftment in vivo.