Wiskott-Aldrich syndrome: a study of 577 patients defines the genotype as a biomarker for disease severity and survival.

ABSTRACT: Wiskott-Aldrich syndrome (WAS) is a multifaceted monogenic disorder with a broad disease spectrum and variable disease severity and a variety of treatment options including allogeneic hematopoietic stem cell transplantation (HSCT) and gene therapy (GT). No reliable biomarker exists to predict disease course and outcome for individual patients. A total of 577 patients with a WAS variant from 26 countries and a median follow-up of 8.9 years (range, 0.3-71.1), totaling 6118 patient-years, were included in this international retrospective study. Overall survival (OS) of the cohort (censored at HSCT or GT) was 82% (95% confidence interval, 78-87) at age 15 years and 70% (61-80) at 30 years. The type of variant was predictive of outcome: patients with a missense variant in exons 1 or 2 or with the intronic hot spot variant c.559+5G>A (class I variants) had a 15-year OS of 93% (89-98) and a 30-year OS of 91% (86-97), compared with 71% (62-81) and 48% (34-68) in patients with any other variant (class II; P < .0001). The cumulative incidence rates of disease-related complications such as severe bleeding (P = .007), life-threatening infection (P < .0001), and autoimmunity (P = .004) occurred significantly later in patients with a class I variant. The cumulative incidence of malignancy (P = .6) was not different between classes I and II. It confirms the spectrum of disease severity and quantifies the risk for specific disease-related complications. The class of the variant is a biomarker to predict the outcome for patients with WAS.

Recommendations for the management of acute immune thrombocytopenia in children. A Consensus Conference from the Italian Association of Pediatric Hematology and Oncology.

BACKGROUND: Immune thrombocytopenia (ITP) is an acquired immune-mediated bleeding disorder characterized by isolated thrombocytopenia. Its estimated yearly incidence in the pediatric population is 1.9-6.4/100,000. ITP in children is usually a self-limiting and benign disorder. The clinical management of children with ITP often remains controversial, as robust randomized trials on the management of this disorder are lacking. Treatments vary widely in clinical practice and existing guidelines from hematology societies on clinical management offer indications based largely on expert opinion rather than strong evidence. MATERIALS AND METHODS: The Coagulative Disorder Working Group of the Italian Association of Pediatric Hematology and Oncology (AIEOP) developed this document to collect shared expert opinions on the management of newly diagnosed ITP, updating previous guidelines and providing recommendations to pediatricians. Each statement has been given a score expressing the strength of evidence, appropriateness and agreement among participants. RESULTS: Clear-cut definitions of the clinical phases of the disease and clinical response are stated. Recommendations are given regarding the classification of bleeding symptoms, evaluation of bleeding risk, diagnosis, and prognostic factors. Specific recommendations for treatment include indications for first-line (intravenous immunoglobulins, steroids) and second-line (combined therapy, thrombopoietin receptor agonists, immunosuppressive drugs, rituximab) therapeutic agents, as well as hemorrhagic emergency and supportive treatment, including emergency splenectomy. The optimal follow-up schedule, the relation between ITP and vaccines and health-related quality-of-life issues are also discussed. DISCUSSION: The panel achieved broad consensus on issues related to how to treat children with newly diagnosed ITP, providing a comprehensive review of all relevant clinical aspects.

Neonatal alloimmune neutropenia: diagnosis and management of 31 Italian patients.

BACKGROUND: In neonates, antibody-mediated destruction of neutrophils may occur as a consequence of auto- or isoimmune disorders. There are few studies on this topic, and particularly on neonatal alloimmune neutropenia (NAN). MATERIALS AND METHODS: We retrospectively evaluated the clinical and molecular/serological findings of 83 neutropenic infants referred to our Reference Laboratory for diagnostic evaluation of NAN, from 2008 to 2021. We also genotyped 260 Italian healthy subjects for the four principal human neutrophil antigens (HNA). RESULTS: The diagnosis of NAN was confirmed in 31 cases. The other 52 cases were autoimmune neutropenia (n=21), neutropenia caused by maternal neutrophil autoantibodies (n=8), neutropenia of non-immune origin (n=17), and cases in which a diagnosis could not be reached (n=6). The median age at neutropenia onset and absolute neutrophil count (ANC) were significantly lower in NAN than in non-NAN cases (1 vs 30 days, p<0.005; 330 vs 580/µL, p=0.003, respectively). About 74% of NAN cases developed neutropenia within the first week of life and laboratory investigations were required within 2 weeks. In five patients the neutropenia was discovered at the end of the first month of life and they were referred to our laboratory 1-2 months later when neutropenia had already resolved. Infections were seen in 19% of NAN cases. The median time to resolution of NAN was 31 days. About 50% of NAN cases were due to alloantibodies against HNA-1b, the most frequent allele of HNA-1 in the Italian population (allele frequency 0.63). In five cases of NAN the mothers had an HNA-1 null phenotype, a frequency higher than that observed in our Italian cohort. DISCUSSION: NAN should be considered by clinicians in infants with neutropenia onset within 5-7 days of life, even though there can be other reasons for a low ANC. If neutropenia is detected later, benign neutropenia seems more likely, although persistence of maternal alloantibodies cannot be ruled out.

Transfusional Approach in Multi-Ethnic Sickle Cell Patients: Real-World Practice Data From a Multicenter Survey in Italy.

Sickle cell disease (SCD) is a worldwide distributed hereditary red cell disorder characterized by recurrent acute vaso-occlusive crises (VOCs and anemia). Gold standard treatments are hydroxycarbamide (HC) and/or different red blood cell (RBC) transfusion regimens to limit disease progression. Here, we report a retrospective study on 1,579 SCD patients (median age 23 years; 802 males/777 females), referring to 34 comprehensive Italian centers for hemoglobinopathies. Although we observed a similar proportion of Caucasian (47.9%) and African (48.7%) patients, Italian SCD patients clustered into two distinct overall groups: children of African descent and adults of Caucasian descent. We found a subset of SCD patients requiring more intensive therapy with a combination of HC plus chronic transfusion regimen, due to partial failure of HC treatment alone in preventing or reducing sickle cell-related acute manifestations. Notably, we observed a higher use of acute transfusion approaches for SCD patients of African descent when compared to Caucasian subjects. This might be related to (i) age of starting HC treatment; (ii) patients' low social status; (iii) patients' limited access to family practitioners; or (iv) discrimination. In our cohort, alloimmunization was documented in 135 patients (8.5%) and was more common in Caucasians (10.3%) than in Africans (6.6%). Alloimmunization was similar in male and female and more frequent in adults than in children. Our study reinforces the importance of donor-recipient exact matching for ABO, Rhesus, and Kell antigen systems for RBC compatibility as a winning strategy to avoid or limit alloimmunization events that negatively impact the clinical management of SCD-related severe complications. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT03397017.

Management strategies for newly diagnosed immune thrombocytopenia in Italian AIEOP Centres: do we overtreat? Data from a multicentre, prospective cohort study.

BACKGROUND: The aim of the present study was to assess management strategies for immune thrombocytopenia (ITP) among Italian paediatric haematologists, and to compare these with those of recent international guidelines. Predictors of early remission or disease chronicity were also evaluated. MATERIALS AND METHODS: During a period of 1 year, 205 children (age: 1 month-18 years) with newly diagnosed ITP were prospectively enrolled by 16 centres belonging to the Italian Association of Paediatric Haematology and Oncology (AIEOP). We collected the subjects demographic data, history, clinical symptoms, platelet count and treatment at presentation and at subsequent visits. RESULTS: Of the 205 patients, 47 (23%) were initially managed with a wait-and-see approach. Compared to these patients, children administered platelet-enhancing therapies were significantly younger (median age: 4.75 vs 7.96 years; p<0.001) and had lower platelet counts. At the 3-month follow-up, 92/202 patients (46%) had persistent ITP. Recovery within 3 months was predicted by younger median age (5.3 vs 7.8 years; p<0.001), and recent viral infection (p<0.001) . At 1 year, 56 patients had chronic ITP, which was associated with older median age (7.54 vs 5.35 years; p<0.001), and a family history of autoimmunity (p<0.05; relative risk: 1.81; 95% confidence interval: 1.09-2.98). In total, 357 pharmacological treatments were recorded (216 intravenous immunoglobulins, 80 steroids). Response to intravenous immunoglobulins did not have an effect on remission rate at 12 months. DISCUSSION: Pediatric hematologists in Italian Centre treat over three-quarters of patients with newly diagnosed ITP, despite recent international guidelines. Almost 80% of patients with mild clinical symptoms received pharmacological treatment at diagnosis, which was significantly associated with younger age. Chronicity at 12 months was not affected by different therapeutic approaches at diagnosis or response to therapy.

Physical activity improved by adherence to prophylaxis in an Italian population of children, adolescents and adults with severe haemophilia A: the SHAPE Study.

BACKGROUND: Physical activity in people with haemophilia (PWH) reduces the development of severe arthropathy, but it must be performed after regular, proper prophylaxis. Strict adherence to treatment is crucial to achieving effectiveness and established outcomes. The primary aim of this study was to collect prospective data on adherence to prophylaxis for over 36 months. A secondary aim was to verify whether adherence correlates with physical activity. MATERIALS AND METHODS: Italian patients with severe haemophilia A treated on prophylaxis with octocog alfa were included in the study. Physical findings were assessed by the Haemophilia and Exercise Project (HEP)-Test-Q and the Early Prophylaxis Immunologic Challenge (EPIC)-Norfolk Physical Activity Questionnaire; orthopaedic status was assessed by the Hemophilia Joint Health Score (HJHS). Adherence was measured as percentage of empty vials returned with respect to the prescribed amount. RESULTS: Forty-two PWH were enrolled: 31% children, 21.4% adolescents, and 47.6% adults. Type, frequency and impact of physical activities differed among the three groups. The HEP-Test-Q showed the highest impairments in the domains "endurance" and "strength/co-ordination". Eight percent of patients were classified as adherent to prophylaxis. Among them, 50% had at least one bleeding episode in the year before enrolment; this percentage dropped during the three years of the study. While remaining stable in the "non-adherent" group, the HJHS score decreased in the "adherent" patients. The mean number of school/work days lost was lower in adherent patients (from 3.4±6.8 to 0.2±0.9) than in non-adherent ones. DISCUSSION: PWH with better orthopaedic scores reported better physical performance. Adherence to long-term prophylaxis proved to be high and correlated with a reduction in bleeds, target joints, school/work days lost, and with a performance improvement in endurance sports activities over time.

Emergency management in patients with haemophilia A and inhibitors on prophylaxis with emicizumab: AICE practical guidance in collaboration with SIBioC, SIMEU, SIMEUP, SIPMeL and SISET.

Emicizumab has been approved in several countries for regular prophylaxis in patients with congenital haemophilia A and FVIII inhibitors because it substantially reduces their bleeding risk and improves quality of life. However, although significantly less frequent, some breakthrough bleeds may still occur while on emicizumab, requiring treatment with bypassing or other haemostatic agents. Thrombotic complications have been reported with the associated use of activated prothrombin complex concentrates. In addition, when surgery/invasive procedures are needed while on emicizumab, their management requires multidisciplinary competences and direct supervision by experts in the use of this agent. Given this, and in order to expand the current knowledge on the use of emicizumab and concomitant haemostatic agents, and reduce the risk of complications in this setting, the Italian Association of Haemophilia Centres (AICE) here provides guidance on the management of breakthrough bleeds and surgery in emergency situations in patients with haemophilia A and inhibitors on emicizumab prophylaxis. This paper has been shared with other National Scientific Societies involved in the field.

Human Fibrinogen Concentrate and Fresh Frozen Plasma in the Management of Severe Acquired Hypofibrinogenemia in Children With Acute Lymphoblastic Leukemia: Results of a Retrospective Survey.

OBJECTIVE OF THE STUDY: In this study we aimed to retrospectively evaluate how centers, belonging to the Associazione Italiana Ematologia e Oncologia Pediatrica (AIEOP), manage severe acquired hypofibrinogenemia in children with acute lymphoblastic leukemia, particularly evaluating the therapeutic role of human fibrinogen concentrate (HFC) and fresh frozen plasma (FFP). METHODS: We conducted a survey among AIEOP centers; thereafter, we collected and analyzed data with regard to the treatment of episodes of severe acquired hypofibrinogenemia occurring during the induction and reinduction phases of the AIEOP-BFM ALL 2009 protocol. RESULTS: In total, 15 of the 37 AIEOP centers invited to join the survey agreed to collect the data, with 10 and 5 centers declaring to react to severe acquired hypofibrinogenemia (<70 mg/dL) by administering HFC or FFP, respectively. Of the 150 episodes of severe hypofibrinogenemia occurring in 101 patients, 47.3% were treated with HFC and 52.7% with FFP, with a normalization of fibrinogen levels achieved in greater proportion and in a shorter amount of time in the HFC group as compared with the FFP group. None of the patients presented with bleeding or thrombosis during the observation period. CONCLUSIONS: Even with the limitations of the retrospective nature of this study, HFC seems to be a safe and effective alternative to FFP for replacement therapy in case of severe hypofibrinogenemia in children with acute lymphoblastic leukemia.

Metagenomic Discovery of 83 New Human Papillomavirus Types in Patients with Immunodeficiency.

Several immunodeficiencies are associated with high susceptibility to persistent and progressive human papillomavirus (HPV) infection leading to a wide range of cutaneous and mucosal lesions. However, the HPV types most commonly associated with such clinical manifestations in these patients have not been systematically defined. Here, we used virion enrichment, rolling circle amplification, and deep sequencing to identify circular DNA viruses present in skin swabs and/or wart biopsy samples from 48 patients with rare genetic immunodeficiencies, including patients with warts, hypogammaglobulinemia, infections, myelokathexis (WHIM) syndrome, or epidermodysplasia verruciformis (EV). Their profiles were compared with the profiles of swabs from 14 healthy adults and warts from 6 immunologically normal children. Individual patients were typically infected with multiple HPV types; up to 26 different types were isolated from a single patient (multiple anatomical sites, one time point). Among these, we identified the complete genomes of 83 previously unknown HPV types and 35 incomplete genomes representing possible additional new types. HPV types in the genus Gammapapillomavirus were common in WHIM patients, whereas EV patients mainly shed HPVs from the genus Betapapillomavirus. Preliminary evidence based on three WHIM patients treated with plerixafor, a leukocyte mobilizing agent, suggest that longer-term therapy may correlate with decreased HPV diversity and increased predominance of HPV types associated with childhood skin warts.IMPORTANCE Although some members of the viral family Papillomaviridae cause benign skin warts (papillomas), many human papillomavirus (HPV) infections are not associated with visible symptoms. For example, most healthy adults chronically shed Gammapapillomavirus (Gamma) virions from apparently healthy skin surfaces. To further explore the diversity of papillomaviruses, we performed viromic surveys on immunodeficient individuals suffering from florid skin warts. Our results nearly double the number of known Gamma HPV types and suggest that WHIM syndrome patients are uniquely susceptible to Gamma HPV-associated skin warts. Preliminary results suggest that treatment with the drug plerixafor may promote resolution of the unusual Gamma HPV skin warts observed in WHIM patients.

Interleukin-12 and Interleukin-23 Blockade in Leukocyte Adhesion Deficiency Type 1.

A patient with leukocyte adhesion deficiency type 1 (LAD1) had severe periodontitis and an intractable, deep, nonhealing sacral wound. We had previously found a dominant interleukin-23-interleukin-17 signature at inflamed sites in humans with LAD1 and in mouse models of the disorder. Blockade of this pathway in mouse models has resulted in resolution of the immunopathologic condition. We treated our patient with ustekinumab, an antibody that binds the p40 subunit of interleukin-23 and interleukin-12 and thereby blocks the activity of these cytokines, inhibiting interleukin-23-dependent production of interleukin-17. After 1 year of therapy, our patient had resolution of his inflammatory lesions without serious infections or adverse reactions. Inhibition of interleukin-23 and interleukin-17 may have a role in the management of LAD1. (Funded by the National Institute of Allergy and Infectious Diseases and others.).

Diagnosis and management of newly diagnosed childhood autoimmune haemolytic anaemia. Recommendations from the Red Cell Study Group of the Paediatric Haemato-Oncology Italian Association.

Autoimmune haemolytic anaemia is an uncommon disorder to which paediatric haematology centres take a variety of diagnostic and therapeutic approaches. The Red Cell Working Group of the Italian Association of Paediatric Onco-haematology (Associazione Italiana di Ematologia ed Oncologia Pediatrica, AIEOP) developed this document in order to collate expert opinions on the management of newly diagnosed childhood autoimmune haemolytic anaemia.The diagnostic process includes the direct and indirect antiglobulin tests; recommendations are given regarding further diagnostic tests, specifically in the cases that the direct and indirect antiglobulin tests are negative. Clear-cut definitions of clinical response are stated. Specific recommendations for treatment include: dosage of steroid therapy and tapering modality for warm autoimmune haemolytic anaemia; the choice of rituximab as first-line therapy for the rare primary transfusion-dependent cold autoimmune haemolytic anaemia; the indications for supportive therapy; the need for switching to second-line therapy. Each statement is provided with a score expressing the level of appropriateness and the agreement among participants.

Alterations in the brain adenosine metabolism cause behavioral and neurological impairment in ADA-deficient mice and patients.

Adenosine Deaminase (ADA) deficiency is an autosomal recessive variant of severe combined immunodeficiency (SCID) caused by systemic accumulation of ADA substrates. Neurological and behavioral abnormalities observed in ADA-SCID patients surviving after stem cell transplantation or gene therapy represent an unresolved enigma in the field. We found significant neurological and cognitive alterations in untreated ADA-SCID patients as well as in two groups of patients after short- and long-term enzyme replacement therapy with PEG-ADA. These included motor dysfunction, EEG alterations, sensorineural hypoacusia, white matter and ventricular alterations in MRI as well as a low mental development index or IQ. Ada-deficient mice were significantly less active and showed anxiety-like behavior. Molecular and metabolic analyses showed that this phenotype coincides with metabolic alterations and aberrant adenosine receptor signaling. PEG-ADA treatment corrected metabolic adenosine-based alterations, but not cellular and signaling defects, indicating an intrinsic nature of the neurological and behavioral phenotype in ADA deficiency.

Diagnosis, Treatment and Long-Term Follow Up of Patients with ADA Deficiency: a Single-Center Experience.

PURPOSE: We carried out a retrospective analysis of 27 patients with Adenosine Deaminase (ADA) deficiency diagnosed in a single center from 1997 to the 2013, for evaluating whether data regarding types of disease-inducing mutations, biochemical and immunological features as well as clinical outcomes of patients treated with enzyme replacement or transplantation, were comparable to those obtained in multicenter studies. METHODS: The ADA deficiency diagnosis was performed with biochemical, immunological and molecular techniques. Ten patients treated with hematopoietic stem cell transplantation and three in treatment with enzyme replacement were followed up in our center. RESULTS: Twenty-four different mutations were identified and five were not previously reported. Identical mutations were found among patients from the same Romani ethnic group or from the same geographical region. A more rapid recovery was observed in enzyme replacement treated patients in comparison with those transplanted that, however, showed a continuous and long-lasting improvement both in terms of immune and metabolic recovery. CONCLUSION: The data obtained in our single center are comparable with those that have been reported in multicenter surveys.

Are all cases of paediatric essential thrombocythaemia really myeloproliferative neoplasms? Analysis of a large cohort.

Sporadic essential thrombocythaemia (ET) is rare in paediatrics, and the diagnostic and clinical approach to paediatric cases cannot be simply copied from experience with adults. Here, we assessed 89 children with a clinical diagnosis of ET and found that 23 patients (25·8%) had a clonal disease. The JAK2 V617F mutation was identified in 14 children, 1 child had the MPL W515L mutation, and 6 had CALR mutations. The monoclonal X-chromosome inactivation pattern was seen in six patients (two with JAK2 V617F and two with CALR mutations). The other 66 patients (74·2%) had persistent thrombocytosis with no clonality. There were no clinical or haematological differences between the clonal and non-clonal patients. The relative proportion of ET-specific mutations in the clonal children was much the same as in adults. The higher prevalence of non-clonal cases suggests that some patients may not have myeloproliferative neoplasms, with significant implications for their treatment.

Cardiomyopathy in a male patient with neutropenia and growth delay.

Neutropenia encompasses a family of neutropenic disorders, both permanent and intermittent, ranging from severe (<500 neutrophils/mm(3)) to mild (500-1500 neutrophils/mm(3)), which may also affect other organ systems such as the pancreas, central nervous system, heart, muscle and skin. Neutropenia can lead to life-threatening pyogenic infections whose severity is roughly inversely proportional to the circulating neutrophil counts.When neutropenia is detected, an attempt should be made to establish the etiology, and to distinguish acquired forms (the most frequent, including post viral neutropenia and autoimmune neutropenia) and congenital forms (rare disorders) that may be either isolated or part of a complex rare genetic disease. We report on a male patient initially diagnosed with isolated neutropenia who later turned out to be affected with Barth syndrome, a rare complex inherited disorder.

Occurrence of nodular lymphocyte-predominant hodgkin lymphoma in hermansky-pudlak type 2 syndrome is associated to natural killer and natural killer T cell defects.

Hermansky Pudlak type 2 syndrome (HPS2) is a rare autosomal recessive primary immune deficiency caused by mutations on ß3A gene (AP3B1 gene). The defect results in the impairment of the adaptor protein 3 (AP-3) complex, responsible for protein sorting to secretory lysosomes leading to oculo-cutaneous albinism, bleeding disorders and immunodeficiency. We have studied peripheral blood and lymph node biopsies from two siblings affected by HPS2. Lymph node histology showed a nodular lymphocyte predominance type Hodgkin lymphoma (NLPHL) in both HPS2 siblings. By immunohistochemistry, CD8 T-cells from HPS2 NLPHL contained an increased amount of perforin (Prf) + suggesting a defect in the release of this granules-associated protein. By analyzing peripheral blood immune cells we found a significant reduction of circulating NKT cells and of CD56(bright)CD16(-) Natural Killer (NK) cells subset. Functionally, NK cells were defective in their cytotoxic activity against tumor cell lines including Hodgkin Lymphoma as well as in IFN-γ production. This defect was associated with increased baseline level of CD107a and CD63 at the surface level of unstimulated and IL-2-activated NK cells. In summary, these results suggest that a combined and profound defect of innate and adaptive effector cells might explain the susceptibility to infections and lymphoma in these HPS2 patients.