T Cell-Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis (HLH) Occurs in Non-Asians and Is Associated with a T Cell Activation State that Is Comparable to Primary HLH.

PURPOSE: T cell-Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (T cell-EBV-HLH) is prevalent in East Asia and has poor prognosis. Understanding of this disease is limited, and literature regarding prevalence in North America is scarce. Herein, we summarize our experience. METHODS: A retrospective analysis of T cell-EBV-HLH patients admitted to Children's Healthcare of Atlanta (GA, USA) from 2010 to 2020 was conducted. Additional immune studies were completed in a subset of patients. RESULTS: We report 15 patients (10 months-19 years of age) diagnosed with T cell-EBV-HLH. Nine patients were Hispanic, and the majority did not have primary HLH (p-HLH) gene defects. Soluble interleukin-2 receptor levels in T cell-EBV-HLH were significantly higher than other forms of secondary-HLH but comparable to p-HLH, and it correlated with disease severity at presentation. Natural killer cell function was decreased in most patients despite a negative workup for p-HLH. Depending on disease severity, initial therapy included dexamethasone or dexamethasone and etoposide. Refractory patients were managed with blended regimens that included one or more of the following therapies: combination chemotherapy, alemtuzumab, emapalumab, and nivolumab. Rituximab did not appreciably decrease EBV viremia in most patients. Non-critically ill patients responded well to immunosuppressive therapy and are long-term survivors without undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Alemtuzumab resulted in inflammation flare in two of the three patients. Three patients underwent allogeneic HSCT, with disease relapse noted in one. At a median follow-up of 3 years, 10 of the 15 patients are alive. CONCLUSION: T cell-EBV-HLH occurs in the USA among the non-Asian populations, especially in those who are Hispanic.

Hemophagocytic lymphohistiocytosis and congenital factor VII deficiency: a case report.

BACKGROUND: Hemophagocytic lymfohistiocytosis (HLH) is a rare, life-threatening hyperinflammation, characterized by immune system over-activation resulting in hemophagocytosis. HLH could appear as a primary disease caused by mutations of immune-regulatory genes, or develop as a result of viral or bacterial infections, or malignancy. Congenital factor VII (FVII) deficiency is a rare autosomal recessive disorder characterized by prolonged prothrombin time (PT) and low FVII, which may increase bleeding risk. CASE PRESENTATION: A 50-year-old woman was admitted for a fever persisted for 20 days, presenting with cytopenia, high hyperferritinemia, low activity of NK cells. Bone marrow aspiration showed hemophagocytosis. CT scanning found pulmonary infection. EBV and CMV were not detected. Genetic scanning did not find pathogenic mutation of a HLH NGS panel including 26 genes. This patient was treated as recommended by the HLH 2004 Guidelines. Coagulation tests identified FVII deficiency. Genetic analysis of F7 gene in the patient and her family members identified recurrent compound heterozygous F7 c.64 + 5G > A and c.1224 T > G (p.His408Gln) mutations in this patient and her brother who showed postoperative hemorrhage after surgical resection of renal cell carcinoma. Heterozygotes in this family were asymptomatic. CONCLUSIONS: To our knowledge, this is the first report of HLH in combination with congenital FVII deficiency in Chinese population.

A Case Report of Primary Nasal Natural Killer (NK)/T-Cell Lymphoma in an African American Patient Presenting with Hemophagocytic Syndrome.

BACKGROUND Extranodal natural killer/T-cell lymphoma, nasal type (ENKTCL) is generally an aggressive and rare non-Hodgkin lymphoma. It is most common in East Asians, Native Americans, and South Americans, but is rarely reported in blacks. CASE REPORT A 55-year-old African American male born in Grenada presented with a left nostril mass with facial swelling and biopsy subsequently confirmed a diagnosis of extranodal NK/T-cell lymphoma, nasal type (ENKTCL). Immunochemistry was positive for CD2, cytoplasmic CD3, CD7, CD 43, CD 56, granzyme B, and TIA-1. In situ hybridization was positive for Epstein-Barr virus encoded ribonucleic acid (EBERs). Bone marrow aspiration did not show lymphoma involvement. The patient had progressive neutropenia upon presentation, with further investigations showing hepatomegaly, hyperferritinemia, and hemophagocytosis in the bone marrow. We reached a diagnosis of hemophagocytic syndrome. He was treated with a high-dose combination chemotherapy and radiation therapy; the neutropenia improved significantly with steroids as treatment for immune activation in the setting of hemophagocytic syndrome. CONCLUSIONS To the best of our knowledge, this is the only second report of extranodal NK/T-cell lymphoma, nasal type in a black patient, and it raises the awareness of early recognition of rare manifestations of NK/T-cell lymphoma such as hemophagocytic syndrome.

[A multicenter retrospective etiological analysis of 601 patients with hemophagocytic lymphohistiocytosis in China].

OBJECTIVE: To investigate the prevalence and etiology of hemophagocytic lymphohistiocytosis (HLH) in different age groups. METHODS: Clinical data of patients with HLH were retrospectively collected from June 2005 to March 2014 in 49 hospitals in China. These patients were divided into child, youth, middle-aged and elderly groups according to the age of onset; meanwhile divided into primary HLH group, infection-associated HLH group, tumor-associated HLH group, rheumatic disease-associated HLH group according to the etiology. Prevalence rates, gender and underlying diseases of each group were retrospectively analyzed. RESULTS: A total of 601 patients were included in the study, age ranging from 1 month to 82 years. The median age of onset was 27 years and 26 years respectively in males(316 cases) and females (285 cases) without statistical significance (P=0.622). There were 171 in child group (28.5%); 262 in youth group(43.6%); 104 in middle-aged group(17.3%); 64 in elderly group(10.6%). The most common causes were infections in child group, malignancies and infections in youth group, malignancies in middle-aged group as well as elderly group. There were 48 patients in primary HLH group(8.0%), 197 in infection-associated HLH group(32.78%), 208 in tumor-associated HLH group(34.61%), 56 in rheumatic disease-associated HLH group(9.32%). Patients with primary HLH were significantly younger than those with secondary HLH (P<0.001), however the tumor-associated HLH group was the eldest. Primary HLH, infection-associated HLH and tumor-associated HLH had more male patients but without statistical significance (P=0.196), while rheumatic disease-associated HLH was mostly female patients (P<0.001). CONCLUSIONS: HLH is not a disease peculiar to children, instead, it may occur in all ages. There are a variety of etiology in different age groups, and a possible link between sex and HLH development. In clinical practice, due attention should be paid to the patients with suspected HLH. Positive relevant inspections may aid in the final diagnosis.

The 253-kb inversion and deep intronic mutations in UNC13D are present in North American patients with familial hemophagocytic lymphohistiocytosis 3.

BACKGROUND: The mutations in UNC13D are responsible for familial hemophagocytic lymphohistiocytosis (FHL) type 3. A 253-kb inversion and two deep intronic mutations, c.118-308C > T and c.118-307G > A, in UNC13D were recently reported in European and Asian FHL3 patients. We sought to determine the prevalence of these three non-coding mutations in North American FHL patients and evaluate the significance of examining these new mutations in genetic testing. PROCEDURE: We performed DNA sequencing of UNC13D and targeted analysis of these three mutations in 1,709 North American patients with a suspected clinical diagnosis of hemophagocytic lymphohistiocytosis (HLH). RESULTS: The 253-kb inversion, intronic mutations c.118-308C > T and c.118-307G > A were found in 11, 15, and 4 patients, respectively, in which the genetic basis (bi-allelic mutations) explained 25 additional patients. Taken together with previously diagnosed FHL3 patients in our HLH patient registry, these three non-coding mutations were found in 31.6% (25/79) of the FHL3 patients. The 253-kb inversion, c.118-308C > T and c.118-307G > A accounted for 7.0%, 8.9%, and 1.3% of mutant alleles, respectively. Significantly, eight novel mutations in UNC13D are being reported in this study. To further evaluate the expression level of the newly reported intronic mutation c.118-307G > A, reverse transcription PCR and Western blot analysis revealed a significant reduction of both RNA and protein levels suggesting that the c.118-307G > A mutation affects transcription. CONCLUSIONS: These specified non-coding mutations were found in a significant number of North American patients and inclusion of them in mutation analysis will improve the molecular diagnosis of FHL3.

Causes and significance of markedly elevated serum ferritin levels in an academic medical center.

OBJECTIVE: A markedly elevated serum ferritin level has been associated with inflammatory conditions such as adult-onset Still's disease, systemic juvenile idiopathic arthritis, and hemophagocytic lymphohistiocytosis/macrophage activation syndrome. Hyperferritinemia, however, can also be caused by a wide variety of disparate conditions, often with impressively high serum levels. The objective of this analysis was to investigate the underlying etiology of markedly elevated ferritin levels in a large group of patients treated as outpatients and inpatients in a tertiary-care medical center. METHODS: Data of all adult patients from 2008 through 2010 with at least 1 serum ferritin level greater than 1000 µg/L were reviewed. If a patient had multiple qualifying levels, the highest one was used. For each case, the most likely cause of the elevated ferritin was assessed based on the available clinical data using a simple algorithmic approach. RESULTS: Six hundred twenty-seven patients were found. The average serum ferritin level was 2647 µg/L. The most frequent condition was malignancy (153/627), with iron-overload syndromes the second most common (136/627). There were 6 cases of adult-onset Still's disease, systemic juvenile idiopathic arthritis, or hemophagocytic lymphohistiocytosis/macrophage activation syndrome. The average ferritin level in these syndromes was 14242 µg/L. Seven patients appeared to have anemia of chronic inflammation, and in 5 patients, there was no clearly definable cause for hyperferritinemia. CONCLUSIONS: Although extremely elevated ferritin levels may be associated with rheumatologic diseases, more often they are found in patients with other conditions such as malignancy or infection. In addition, extremely high ferritin levels can be found in patients with seemingly indolent disease or levels of chronic inflammation.

Distinct mutations in STXBP2 are associated with variable clinical presentations in patients with familial hemophagocytic lymphohistiocytosis type 5 (FHL5).

Familial hemophagocytic lymphohistiocytosis (FHL) is a genetically determined hyperinflammatory syndrome caused by uncontrolled immune response mediated by T-lymphocytes, natural killer (NK) cells, and macrophages. STXBP2 mutations have recently been associated with FHL5. To better characterize the genetic and clinical spectrum of FHL5, we analyzed a cohort of 185 patients with suspected FHL for mutations in STXBP2. We detected biallelic mutations in 37 patients from 28 families of various ethnic origins. Missense mutations and mutations affecting 1 of the exon 15 splice sites were the predominant changes detectable in this cohort. Patients with exon 15 splice-site mutations (n = 13) developed clinical manifestations significantly later than patients with other mutations (median age, 4.1 year vs 2 months) and showed less severe impairment of degranulation and cytotoxic function of NK cells and CTLs. Patients with FHL5 showed several atypical features, including sensorineural hearing deficit, abnormal bleeding, and, most frequently, severe diarrhea that was only present in early-onset disease. In conclusion, we report the largest cohort of patients with FHL5 so far, describe an extended disease spectrum, and demonstrate for the first time a clear genotype-phenotype correlation.

The outcome of hematopoietic stem cell transplantation in Korean children with hemophagocytic lymphohistiocytosis.

Chemoimmunotherapy-based treatments have improved the survival of patients with HLH, but outcomes of the patients are still unsatisfactory. We report here the outcome of Korean children with HLH who underwent HSCT, which was analyzed from the data of a nation-wide HLH registry. Retrospective nation-wide data recruitment for the pediatric HLH patients diagnosed between 1996 and 2008 was carried out by the Histiocytosis Working Party of the Korean Society of Hematology. Nineteen patients who received HSCT among the total of 148 enrolled children with HLH were analyzed for the transplant-related variables and events. The probability of five-yr survival after HSCT was 73.3% with a median follow-up of 57. Two months compared to 54.3% for the patients who were treated with chemoimmunotherapy only (p = 0.05). The reasons for HSCT were active disease after eight wk of initial treatment (n = 9), relapsed disease (n = 5), and FHL (n = 5). Fourteen patients are currently alive without disease after HSCT, four patients died of treatment-related events (infection in two and graft failure in two) at early post-transplant period, and one patient died of relapse at one yr post transplantation. The survival of patients who were transplanted because of active disease after eight wk of initial treatment was worse compared to those patients who had inactive state at that time (60.6% vs. 100%, respectively, p = 0.06). Of the four patients who received transplants using cord blood, three died of graft failure (n = 2) and relapse (n = 1). The five-yr probability of survival after HSCT according to the donor type was 85.7% for the MRDs (n = 6), 87.5% for the MUDs (n = 8), and 40% for the MMUDs (n = 5) (p = 0.03). Other variables such as age, CNS involvement at the time of diagnosis, the etiology of HLH (familial or secondary), and the conditioning regimens had no influence on the five-yr OS of the HLH patients who underwent HSCT. HSCT improved the survival of the patients who had familial, relapsed, or severe and persistent SHLH in the Korean nation-wide HLH registry. Although numbers were small, these results are similar to other reports in the literature. The disease state after initial treatment, the stem cell source of the transplant, and the donor type were the important prognostic factors that affected the OS of the HLH patients who underwent HSCT.

Hemophagocytic lymphohistiocytosis in Texas: observations on ethnicity and race.

BACKGROUND: Early recognition and aggressive treatment of hemophagocytic lymphohistiocytosis (HLH) has changed a uniformly fatal disease to one 55% survive. We examined the diagnosis and treatment of pediatric patients with HLH from the three largest academic medical centers in Texas for information on modern non-study treatment and survival. In contrast with previously reported series, the racial and ethnic composition of Texas provided a unique opportunity to evaluate the impact of race and ethnicity on survival with HLH. PROCEDURE: A retrospective chart review of local oncology and pathology databases identified 70 patients with HLH from 1992 to 2007. Median age was 1.8 years (range 0.1-16.5 years) and 43% were Latino. RESULTS: We identified 70 patients with an overall survival of 67% after a median follow-up of 3 months (range 1-139 months). Twenty patients (29%) underwent stem cell transplant (SCT). Seven patients (18%) had mutations in the Perforin, Munc 13-4, or Syntaxin-11 genes, consistent with primary disease. Calculated cross-sectional prevalence of HLH in Texas from our study is 1 in 100,000 children. The effect of Latino ethnicity on survival was not statistically significant. CONCLUSION: HLH is a rare but potentially treatable illness with modern aggressive therapy. Though treatment is more standardized for HLH, the role of race and ethnicity as risk factors for development of disease and impact on outcome may warrant further investigation.

Infection of T lymphocytes in Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in children of non-Asian origin.

BACKGROUND: Epstein-Barr virus (EBV) is one of the most frequent triggers of hemophagocytic lymphohistiocytosis (HLH). EBV-associated HLH (EBV-HLH) and ectopic infection of T cells has been particularly described in patients from Far East Asia. PROCEDURE: In a cohort of 12 children with EBV-HLH treated in Germany, the EB viral load was detected by real-time polymerase chain reaction in plasma and peripheral blood mononuclear cells (PBMC). Virological and clinical data were analyzed retrospectively. RESULTS: Among the 12 mainly German patients, children with underlying immunodeficiencies as well as otherwise healthy individuals were affected. The clinical course ranged from a steroid-responding to a fatal disease despite intensive treatment. Increased EBV copy numbers in plasma and/or PBMC were found in all patients. Serial measurements reflected the course of the disease. Cell-type specific viral load was determined in seven patients and revealed EBV-infection of T cells in all of them. In contrast to the reported Asian patients a significant viral load was also found in B cells. CONCLUSIONS: T cell infection appears to be a typical feature of EBV-associated HLH irrespective of patients ethnic background and the clinical course. Evaluation of cell-type specific infection should be considered when targeted therapy is applied.

Characterization of PRF1, STX11 and UNC13D genotype-phenotype correlations in familial hemophagocytic lymphohistiocytosis.

Familial hemophagocytic lymphohistiocytosis (FHL) is a rare autosomal recessive lethal condition characterized by fever, cytopenia, hepatosplenomegaly and hemophagocytosis. The hallmark of FHL is defect apoptosis triggering and lymphocyte cellular cytotoxicity. Thus far three disease-causing genes (PRF1, UNC13D, STX11) have been identified. We performed a genotype-phenotype study in a large, multi-ethnic cohort of 76 FHL patients originating from 65 unrelated families. Biallelic mutations in PRF1, UNC13D and STX11 were demonstrated in 13/74 (18%), 6/61 (10%) and 14/70 (20%) patients, respectively. In 27/60 (45%) patients analyzed for all three genes, no molecular diagnosis was established. STX11 mutations were most common in Turkish families (7/28, 25%), whereas in Middle East families, PRF1 mutations were most frequent (6/13, 46%). No biallelic mutation was identified in most families of Nordic origin (13/14, 93%). Patients carrying PRF1 mutations had higher risk of early onset (age <6 months) compared to patients carrying STX11 mutations [adjusted odds ratio 8.23 (95% confidence interval [CI] = 1.20-56.40), P = 0.032]. Moreover, patients without identified mutations had increased risk of pathological cerebrospinal fluid (CSF) at diagnosis compared to patients with STX11 mutations [adjusted odds ratio 26.37 (CI = 1.90-366.82), P = 0.015]. These results indicate that the disease-causing mutations in FHL have different phenotypes with regard to ethnic origin, age at onset, and pathological CSF at diagnosis.

Genotype-phenotype study of familial haemophagocytic lymphohistiocytosis due to perforin mutations.

BACKGROUND: PRF1 gene mutations are associated with familial haemophagocytic lymphohistiocytosis type 2 (FHL2). Genotype-phenotype analysis, previously hampered by limited numbers of patients, was for the first time performed by data pooling from five large centres worldwide. PATIENTS AND METHODS: Members of the Histiocyte Society were asked to report cases of FHL2 on specific forms. Data were pooled in a common database and analysed. RESULTS: The 124 patients had 63 different mutations (including 15 novel mutations): 11 nonsense, 10 frameshift, 38 missense and 4 in-frame deletions. Some mutations were found more commonly: 1122 G-->A (W374X), associated with Turkish origin, in 32 patients; 50delT (L17fsX22) associated with African/African American origin, in 21 patients; and 1090-91delCT (L364fsX), in 7 Japanese patients. Flow cytometry showed that perforin expression was absent in 40, reduced in 6 and normal in 4 patients. Patients presented at a median age of 3 months (quartiles: 2, 3 and 13 months), always with fever, splenomegaly and thrombocytopenia. NK activity was absent in 36 (51%), 5% in 4 (6%), "reduced" in 2 (3%) (not reported, n = 54). Nonsense mutations were significantly associated with younger age at onset (p<0.001) and absent natural killer activity (p = 0.008). CONCLUSION: PRF1 mutations are spread over the functional domains. Specific mutations are strongly associated with Turkish, African American and Japanese ethnic groups. Later onset and residual cytotoxic function are observed in patients with at least one missense mutation.

Variations in clinical presentation, frequency of hemophagocytosis and clinical behavior of intravascular lymphoma diagnosed in different geographical regions.

BACKGROUND AND OBJECTIVES: This study explored variations in the clinical manifestations of intravascular lymphoma (IVL) on the bases of the association with hemophagocytosis and the country where the diagnosis was made. DESIGN AND METHODS: The clinical features of 50 Western patients with IVL were compared with those of 123 patients with IVL diagnosed in Eastern countries (87 diagnosed in Japan and 36 in other Asian countries), previously reported in English literature, and collected by an electronic bibliographic search. RESULTS: Hemophagocytosis was absent in Western patients, but reported in 38 (44%) Japanese patients (p=0.00001) and in seven (19%) patients from other Asian countries (p=0.002). No clinical differences were evident between patients with hemophagocytosis-negative IVL diagnosed in Western countries, Japan and other Asian Countries. Conversely, Japanese and non-Japanese patients with hemophagocytosis-related IVL more frequently had stage IV disease, fever, hepato-splenic involvement, marrow infiltration, dyspnea, anemia, and thrombocytopenia, and rarely exhibited cutaneous or central nervous system involvement. Lymph node and peripheral blood involvement was uncommon in all subgroups. In Western patients, anthracycline-based chemotherapy was associated with a 52% remission rate, and a 2-year overall survival of 46%. INTERPRETATION AND CONCLUSIONS: The clinical features of IVL vary according to the association with hemophagocytosis, regardless of the country in which the diagnosis is made. Western, Japanese and other Asian patients with hemophagocytosis-negative IVL display similar clinical characteristics and should be considered as having classical IVL. Patients with hemophagocytosis-related IVL show significantly different clinical features. Both forms have a poor prognosis. Extensive molecular studies are needed to explore whether these clinical differences might reflect discordant biological entities within IVL.

Patients of African ancestry with hemophagocytic lymphohistiocytosis share a common haplotype of PRF1 with a 50delT mutation.

Mutations of the perforin gene (PRF1) are present in a proportion of patients with hemophagocytic lymphohistiocytosis (HLH). We found that all identified infants with HLH of African descent (17 from USA, 4 from Europe) have 50delT-PRF1 (16 homozygotes, 5 compound heterozygotes), accounting for the most frequently observed PRF1 mutation. Two additional patients with HLH, self-reporting as Hispanic, carried 50delT, but no Caucasians were identified with 50delT. To test the hypothesis that this mutation represents a single haplotype, DNA from 23 patients with HLH and 30 African-American control subjects was sequenced for the PRF1 gene, including portions of the intron containing known single nucleotide polymorphisms (SNPs). The same groups were genotyped at 3 microsatellites proximal to PRF1. The SNP profiles of patients with 50delT-PRF1 were identical, and 5 novel SNPs were identified among African-American control subjects. Patients with 50delT-PRF1 were also found to have had an earlier age of disease onset than patients with other PRF1 mutations. Extent of haplotype sharing and variability of microsatellite alleles in 50delT-PRF1 chromosomes suggest that this mutation arose approximately 1000 to 4000 years ago and is restricted to patients of African descent.