Patients with early relapse of primary hemophagocytic syndromes or with persistent CNS involvement may benefit from immediate hematopoietic stem cell transplantation

Hemophagocytic lymphohistiocytosis in Egyptian children: diagnosis, treatment challenges, and outcome

BACKGROUND

Hemophagocyticlymphohistiocytosis (HLH) is a spectrum of immune activation which could be genetically determined, or secondary to an underlying illness. Our aim was to present the clinico-genetic aspects of HLH among Egyptian children and to evaluate the patterns of reactivation and outcome with illustrations of overlap manifestations.

RESEARCH DESIGNAND METHODS

We retrospectively collected the data of 55 patients with HLH, registered at Ain Shams University Children's Hospital,Cairo, Egypt.

RESULTS

Median age at diagnosis was 19 months (range 2-180), 33 patients (60%) fulfilled the diagnostic HLH criteria at presentation. Fourteen (25.45%) patients had secondary HLH, 15 (27.27%) patients had genetically documented familial HLH (11 had variants in UNC13D gene and one in PRF1 gene), 3 had Griscelli and Chediak-Higashi syndromes. Sixteen patients (29.1%) had reactivations, 8 (50%) of them had molecularly confirmed HLH. We report the death of 40 patients, the median duration from the diagnosis to death of 5 months mostly due to disease activity.

CONCLUSIONS

This study confirms that the nonspecific signs and symptoms of HLH are challenging. Genetic testing, though expensive and sophisticated, is integral for the diagnosis. The difficulty in finding non-related donors for stem cell transplantation and the early reactivations are the causes of the inferior outcome.

Ruxolitinib-based regimen in children with primary hemophagocytic lymphohistiocytosis

Primary hemophagocytic lymphohistiocytosis (pHLH) is a rare immune disorder and hematopoietic stem cell transplan- tation (HSCT) is the only potentially curative treatment. Given the high pre-HSCT mortality of pHLH patients reported in the HLH-2004 study (17%), more regimens to effectively control the disease and form a bridge with HSCT are needed. We conducted a retrospective study of pHLH children treated by ruxolitinib (RUX)-based regimen. Generally, patients received RUX until HSCT or unacceptable toxic side-effect. Methylprednisolone and etoposide were added sequentially when the disease was suboptimally controlled. The primary end point was 1-year overall survival. Twenty-one pHLH patients (12 previously treated and 9 previously untreated) were included with a median follow-up of 1.4 years. At last follow-up, 17 (81.0%) patients were alive with a 1-year overall survival of 90.5% (95% confidence interval: 84.1-96.9). Within the first 8 weeks, all patients had an objective response, of which 19 (90.5%) achieved complete response (CR) and two (9.5%) achieved partial response (PR) as a best response. Seventeen (81.0%) patients received HSCT, of which 13 (76.5%) had CR, three (17.6%) had PR and one (5.9%) had disease reactivation at the time of HSCT. Fifteen (88.2) patients were alive post- HSCT. Notably, eight (38.1%) patients received zero doses of etoposide, suggesting the potential of RUX-based regimen to reduce chemotherapy intensity. Patients tolerated RUX-based regimen well and the most frequently observed adverse events were hematologic adverse events. Overall, RUX-based regimen was effective and safe and could be used as a bridge to HSCT for pHLH children.

Treatment Strategies for Central Nervous System Effects in Primary and Secondary Haemophagocytic Lymphohistiocytosis in Children

Purpose of Review

This review presents an appraisal of current therapeutic options for the treatment of central nervous system haemophagocytic lymphohistiocytosis (CNS-HLH) in the context of systemic disease, as well as when CNS features occur in isolation. We present the reader with a diagnostic approach to CNS-HLH and commonly used treatment protocols. We discuss and evaluate newer treatments on the horizon.

Recent Findings

Mortality is high in patients who do not undergo HSCT, and while larger studies are required to establish benefit in many treatments, a number of new treatments are currently being evaluated. Alemtuzumab is being used as a first-line treatment for CNS-HLH in a phase I/II multicentre prospective clinical trial as an alternative to traditional HLH-1994 and 2004 protocols. It has also been used successfully as a second-line agent for the treatment of isolated CNS-HLH that is refractory to standard treatment. Ruxolitinib and emapalumab are new immunotherapies that block the Janus kinase—Signal Transducer and Activator of Transcription (JAK-STAT) pathway that have shown efficacy in refractory HLH, including for CNS-HLH disease.

Summary

Treatment of CNS-HLH often requires HLH-94 or 2004 protocols followed by haematopoietic stem cell transplantation (HSCT) to maintain remission, although relapse can occur, particularly with reduced intensity conditioning if donor chimerism falls. CNS features have been shown to improve or stabilise following HSCT in CNS-HLH in the context of systemic disease and in isolated CNS-HLH. Encouraging reports of early cohort studies suggest alemtuzumab and the Janus kinase (JAK) inhibitor ruxolitinib offer potential salvage therapy for relapsed and refractory CNS-HLH. Newer immunotherapies such as tocilizumab and natalizumab have been shown to be beneficial in sporadic cases. CNS-HLH due to primary gene defects may be amenable to gene therapy in the future.

Stem cell transplantation for children with hemophagocytic lymphohistiocytosis: results from the HLH-2004 study

We report the largest prospective study thus far on hematopoietic stem cell transplantation (HSCT) in hemophagocytic lymphohistiocytosis (HLH), a life-threatening hyperinflammatory syndrome comprising familial/genetic HLH (FHL) and secondary HLH. Although all patients with HLH typically need intensive anti-inflammatory therapy, patients with FHL also need HSCT to be cured. In the international HLH-2004 study, 187 children aged <18 years fulfilling the study inclusion criteria (5 of 8 diagnostic criteria, affected sibling, or molecular diagnosis in FHL-causative genes) underwent 209 transplants (2004-2012), defined as indicated in patients with familial/genetic, relapsing, or severe/persistent disease. Five-year overall survival (OS) post-HSCT was 66% (95% confidence interval [CI], 59-72); event-free survival (EFS) was 60% (95% CI, 52-67). Five-year OS was 81% (95% CI, 65-90) for children with a complete response and 59% (95% CI, 48-69) for those with a partial response (hazard ratio [HR], 2.12; 95% CI, 1.06-4.27; P = .035). For children with verified FHL (family history/genetically verified, n = 134), 5-year OS was 71% (95% CI, 62-78) and EFS was 62% (95% CI, 54-70); 5-year OS for children without verified FHL (n = 53) was significantly lower (52%; 95% CI, 38-65) (P = .040; HR, 1.69; 95% CI, 1.03-2.77); they were also significantly older. Notably, 20 (38%) of 53 patients without verified FHL had natural killer cell activity reported as normal at diagnosis, after 2 months, or at HSCT, suggestive of secondary HLH; and in addition 14 (26%) of these 53 children had no evidence of biallelic mutations despite having 3 or 4 FHL genes analyzed (natural killer cell activity not analyzed after 2 months or at HSCT). We conclude that post-HSCT survival in FHL remains suboptimal, and that the FHL diagnosis should be carefully investigated before HSCT. Pretransplant complete remission is beneficial but not mandatory to achieve post-HSCT survival. This trial was registered at www.clinicaltrials.gov as #NCT00426101.

Central Nervous System Involvement in Hemophagocytic Lymphohistiocytosis in Adults: A Retrospective Analysis of 96 Patients in a Single Center

Background

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome. Central nervous system (CNS) involvement is a severe complication, which can lead to rapid disease development and higher morality. However, this has not been given enough attention in adult HLH. Therefore, we carried out this study to analyze the clinical features, laboratory findings, treatment outcomes, and other characteristics of adult HLH with CNS involvement.

Methods

A retrospective analysis of 96 adult patients with HLH combined with CNS involvement between June 2003 and December 2016 was conducted. Clinical features, cerebrospinal fluid (CSF) features, image changes, and therapeutic outcomes were analyzed.

Results

Among the 96 patients, 86 had various CNS symptoms and 33 (38.4%) had already presented symptoms before the HLH diagnosis was confirmed. A total of 59 patients received CSF examinations and showed abnormalities in 23 patients (39.0%). Seventy patients received imaging examinations and the results showed fifty patients with imaging changes (71.4%). Fifty-seven patients received multiple rounds of repeated intrathecal injection therapy and 35 patients improved (61.4%). As for the multiple analyses of effective factors on survival time, the results showed that the effects of combined Epstein-Barr virus (EBV) infection (P = 0.026, Exp(B) = 2.309, 95% confidence interval [CI] [1.108, 4.823) and intrathecal injection therapy (P = 0.013, Exp(B) = 0.422, 95% CI [0.214, 0.831]) on the survival time of the CNS-HLH patients were significant.

Conclusions

Complication with EBV infection is a risk factor, and intrathecal injection is a protective factor. CNS involvement in HLH is not rare, which can result in a poor prognosis. Multiple rounds of repeated intrathecal injection therapy can improve the prognosis of CNS-HLH patients.

Periodontal and other oral manifestations of immunodeficiency diseases

The list of immunodeficiency diseases grows each year as novel disorders are discovered, classified, and sometimes reclassified due to our ever-increasing knowledge of immune system function. Although the number of patients with secondary immunodeficiencies (SIDs) greatly exceeds those with primary immunodeficiencies (PIDs), the prevalence of both appears to be on the rise probably because of scientific breakthroughs that facilitate earlier and more accurate diagnosis. Primary immunodeficiencies in adults are not as rare as once thought. Globally, the main causes of secondary immunodeficiency are HIV infection and nutritional insufficiencies. Persons with acquired immune disorders such as AIDS caused by the human immunodeficiency virus (HIV) are now living long and fulfilling lives as a result of highly active antiretroviral therapy (HAART). Irrespective of whether the patient's immune-deficient state is a consequence of a genetic defect or is secondary in nature, dental and medical practitioners must be aware of the constant potential for infections and/or expressions of autoimmunity in these individuals. The purpose of this review was to study the most common conditions resulting from primary and secondary immunodeficiency states, how they are classified, and the detrimental manifestations of these disorders on the periodontal and oral tissues.

How to Treat Involvement of the Central Nervous System in Hemophagocytic Lymphohistiocytosis?

OPINION STATEMENT

Central nervous system (CNS)-hemophagocytic lymphohistiocytosis (HLH) is not a disease in itself, but it is part of a systemic immune response. The vast majority of patients with CNS-HLH also have systemic HLH and a large number of patients with primary and secondary HLH have CNS involvement. Reactivations within the CNS are frequent during the course of HLH treatment and may occur concomitant with or independent of systemic relapses. It is also important to consider primary HLH as an underlying cause of "unknown CNS inflammation" as these patients may present with only CNS disease. To initiate proper treatment, a correct diagnosis must be made. A careful review of the patient's history and a thorough neurological examination are essential. In addition to the blood tests required to make a diagnosis of HLH, a lumbar puncture with cerebrospinal fluid (CSF) analysis and magnetic resonance imaging (MRI) should always be done in all cases regardless of the presence or absence of neurological signs or symptom. Treatment options for CNS-HLH include, but are not limited to, those commonly used in systemic HLH, including corticosteroids, etoposide, cyclosporine A, alemtuzumab, and ATG. In addition, intrathecal treatment with methotrexate and corticosteroids has become a standard care and is likely to be beneficial. Therapy must be initiated without inappropriate delay to prevent late effects in HLH. An interesting novel approach is an anti-IFN-gamma antibody (NI-0501), which is currently being tested. Hematopoietic stem cell transplantation (HSCT) also represents an important CNS-HLH treatment; patients with primary HLH may benefit from immediate HSCT even if there is active disease at time of transplantation, though care should be taken to monitor CNS inflammation through HSCT and treat if needed. Since CNS-HLH is a condition leading to the most severe late effects of HLH, early expert consultation is recommended.

Allogeneic hematopoietic stem-cell transplantation for adult and adolescent hemophagocytic lymphohistiocytosis: a single center analysis

Myeloablative conditioning-based allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in the treatment of adult and adolescent hemophagocytic lymphohistiocytosis (HLH) is rarely reported. We conducted a retrospective study of 30 adult and adolescent HLH transplanted for primary HLH (n = 4), tumor-HLH (n = 8), EBV-HLH (n = 14), and underlying disease-unknown (UDU)-HLH (n = 4). Peripheral blood stem cells (PBSCs) were the stem-cell source in all patients. Twenty-three patients were transplanted from HLA-haploidentical family donors, six from HLA-identical sibling donors, and one from a matched unrelated donor. Four patients appeared with mixed chimerism (MC), and no patient presented with graft failure. There was a high risk for EBV reactivation with an incidence of 47 %. Two patients developed post-transplant lymphoproliferative disorder (PTLD) and three were considered primary disease recurrent. With a median follow-up of 26 months, 19 patients survived and 11 patients died. The estimated 2-year overall survival (OS) was 63.3 ± 8.8 % in all patients, 100 % in primary HLH, 64.3 ± 12.8 % in EBV-HLH, 50.0 ± 17.7 % in tumor-HLH, and 50.0 ± 25.0 % in UDU-HLH. Myeloablative conditioning-based allo-HSCT is an effective treatment for adult and adolescent HLH to achieve complete remission and long-term survival.

Hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis: recent advances and controversies

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory clinical syndrome of uncontrolled immune response which results in hypercytokinemia due to underlying primary or secondary immune defect. A number of genetic defects in transport, processing and function of cytotoxic granules which result in defective granule exocytosis and cytotoxicity of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells have been well identified at the cellular and molecular level. Important advances have been made during the last 20 years in the diagnosis and treatment of HLH. The Histiocyte Society has proposed diagnostic guideline using both clinical and laboratory findings in HLH-2004 protocol, and this has been modified partly in 2009. HLH used to be a fatal disease, but the survival of HLH patients has improved to more than 60% with the use of chemoimmunotherapy combined with hematopoietic cell transplantation (HCT) over the past 2 decades. However, HCT is still the only curative option of treatment for primary HLH and refractory/relapsed HLH after proper chemoimmunotherapy. The outcome of HCT for HLH patients was also improved steadily during last decades, but HCT for HLH still carries significant mortality and morbidity. Moreover, there remain ongoing controversies in various aspects of HCT including indication of HCT, donor selection, timing of HCT, conditioning regimen, and mixed chimerism after HCT. This review summarized the important practical issues which were proven by previous studies on HCT for HLH, and tried to delineate the controversies among them.

Towards the targeted management of Chediak-Higashi syndrome

Chediak-Higashi syndrome (CHS) is a rare, autosomal recessive congenital immunodeficiency caused by mutations in CHS1, a gene encoding a putative lysosomal trafficking protein. In the majority of patients, this disorder is typically characterized by infantile-onset hemophagocytic lymphohistiocytosis (HLH), which is lethal unless allogeneic transplantation is performed. A small number of individuals have the attenuated form of the disease and do not benefit from transplant. Improved outcomes of transplantation have been reported when performed before the development of HLH, thus it is important to quickly differentiate patients that present with the childhood form of disease and to prematurely enroll them into a transplantation protocol. In addition, this would also preclude those that exhibit clinical phenotypes of adolescent and adult CHS from this treatment. Patients with an absence of cytotoxic T lymphocyte (CTL) function have a high risk for developing HLH, and could therefore benefit the most from early hematopoietic stem cell transplantation (HSCT). However, although normal CTL cytotoxicity or bi-allelic missense mutations do not exclude the occurrence of HLH in childhood, a more conservative approach is justified. This article summarizes recent advances in the clinical characterization of CHS patients, provides updates on promising new testing methods, and focuses on specific therapeutic approaches.

Chediak-Higashi Syndrome and Premature Exfoliation of Primary Teeth

The Chediak-Higashi syndrome (CHS) is a rare hereditary fatal disease, if not treated. These changes are associated with various diseases and syndromes that mainly cause periodontal disease and thus the premature loss of teeth. This paper describes the monitoring of premature loss of primary teeth that began when the child was 5 years old. On presentation his teeth were mobile and there was a history of gingival bleeding. Panoramic radiography revealed generalized and severe bone loss, and the teeth showed no bony support enough for their stability. Blood test was ordered to assess the overall health of the child and giant cells with cytoplasmic granules were found, confirming the diagnosis of CHS. The management of periodontal disease focused on the control of infection and bacterial plaque by mechanical and chemical methods.

Hemophagocytic lymphohistiocytosis (HLH): a review of literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease in children and an exceptionally rare occurrence in adults. It is categorized broadly into primary (familial) or the secondary types; the latter being associated most commonly with an underlying malignancy. HLH carries a high rate of mortality, and the treatment itself is associated with significant morbidity and risk of mortality. A high degree of suspicion for the diagnosis, early treatment and aggressive supportive care is critical for management. We present a comprehensive review of literature describing the clinical features, diagnosis, management and outcome of HLH.

Familial hemophagocytic lymphohistiocytosis type 5 (FHL-5) is caused by mutations in Munc18-2 and impaired binding to syntaxin 11

Rapid intracellular transport and secretion of cytotoxic granules through the immunological synapse requires a balanced interaction of several proteins. Disturbance of this highly regulated process underlies familial hemophagocytic lymphohistiocytosis (FHL), a genetically heterogeneous autosomal-recessive disorder characterized by a severe hyperinflammatory phenotype. Here, we have assigned FHL-5 to a 1 Mb region on chromosome 19p by using high-resolution SNP genotyping in eight unrelated FHL patients from consanguineous families. Subsequently, we found nine different mutations, either truncating or missense, in STXBP2 in twelve patients from Turkey, Saudi Arabia, and Central Europe. STXBP2 encodes syntaxin binding protein 2 (Munc18-2), involved in the regulation of vesicle transport to the plasma membrane. We have identified syntaxin 11, a SNARE protein mutated in FHL-4, as an interaction partner of STXBP2. This interaction is eliminated by the missense mutations found in our FHL-5 patients, which leads to a decreased stability of both proteins, as shown in patient lymphocytes. Activity of natural killer and cytotoxic T cells was markedly reduced or absent, as determined by CD107 degranulation. Our findings thus identify a key role for STXBP2 in lytic granule exocytosis.