Wiskott-Aldrich Syndrome: A study on 577 patients defining the genotype as a predictive biomarker for disease severity.

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 (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% CI 78-87) at 15 years and 70% (61-80) at 30 years of age. The type of variant was predictive of outcome: patients with a missense variant in exons 1 or 2 or with the intronic hotspot 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 to 71% (62-81) and 48% (34-68) in patients with any other variant (class II; p<0.0001). The cumulative incidence rates of disease-related complications such as severe bleeding (p=0.007), life-threatening infection (p<0.0001), and autoimmunity (p=0.004) occurred significantly later in patients with a class I variant. The cumulative incidence of malignancy (p=0.6) was not different between classes I and II. This study represents the largest cohort of WAS patients studied so far. It confirms the spectrum of disease severity and quantifies the risk for specific disease-related complications. The class of variant is a biomarker to predict the outcome for WAS patients.

Long-term and real-world safety and efficacy of retroviral gene therapy for adenosine deaminase deficiency.

Adenosine deaminase (ADA) deficiency leads to severe combined immunodeficiency (SCID). Previous clinical trials showed that autologous CD34+ cell gene therapy (GT) following busulfan reduced-intensity conditioning is a promising therapeutic approach for ADA-SCID, but long-term data are warranted. Here we report an analysis on long-term safety and efficacy data of 43 patients with ADA-SCID who received retroviral ex vivo bone marrow-derived hematopoietic stem cell GT. Twenty-two individuals (median follow-up 15.4 years) were treated in the context of clinical development or named patient program. Nineteen patients were treated post-marketing authorization (median follow-up 3.2 years), and two additional patients received mobilized peripheral blood CD34+ cell GT. At data cutoff, all 43 patients were alive, with a median follow-up of 5.0 years (interquartile range 2.4-15.4) and 2 years intervention-free survival (no need for long-term enzyme replacement therapy or allogeneic hematopoietic stem cell transplantation) of 88% (95% confidence interval 78.7-98.4%). Most adverse events/reactions were related to disease background, busulfan conditioning or immune reconstitution; the safety profile of the real world experience was in line with premarketing cohort. One patient from the named patient program developed a T cell leukemia related to treatment 4.7 years after GT and is currently in remission. Long-term persistence of multilineage gene-corrected cells, metabolic detoxification, immune reconstitution and decreased infection rates were observed. Estimated mixed-effects models showed that higher dose of CD34+ cells infused and younger age at GT affected positively the plateau of CD3+ transduced cells, lymphocytes and CD4+ CD45RA+ naive T cells, whereas the cell dose positively influenced the final plateau of CD15+ transduced cells. These long-term data suggest that the risk-benefit of GT in ADA remains favorable and warrant for continuing long-term safety monitoring. Clinical trial registration: NCT00598481 , NCT03478670 .

Hemophagocytic inflammatory syndrome in ADA-SCID: report of two cases and literature review.

Hemophagocytic inflammatory syndrome (HIS) is a rare form of secondary hemophagocytic lymphohistiocytosis caused by an impaired equilibrium between natural killer and cytotoxic T-cell activity, evolving in hypercytokinemia and multiorgan failure. In the context of inborn errors of immunity, HIS occurrence has been reported in severe combined immunodeficiency (SCID) patients, including two cases of adenosine deaminase deficient-SCID (ADA-SCID). Here we describe two additional pediatric cases of ADA-SCID patients who developed HIS. In the first case, HIS was triggered by infectious complications while the patient was on enzyme replacement therapy; the patient was treated with high-dose corticosteroids and intravenous immunoglobulins with HIS remission. However, the patient required HLA-identical sibling donor hematopoietic stem cell transplantation (HSCT) for a definitive cure of ADA-SCID, without HIS relapse up to 13 years after HSCT. The second patient presented HIS 2 years after hematopoietic stem cell gene therapy (GT), secondarily to Varicella-Zoster vaccination and despite CD4+ and CD8+ lymphocytes' reconstitution in line with other ADA SCID patients treated with GT. The child responded to trilinear immunosuppressive therapy (corticosteroids, Cyclosporine A, Anakinra). We observed the persistence of gene-corrected cells up to 5 years post-GT, without HIS relapse. These new cases of children with HIS, together with those reported in the literature, support the hypothesis that a major dysregulation in the immune system can occur in ADA-SCID patients. Our cases show that early identification of the disease is imperative and that a variable degree of immunosuppression could be an effective treatment while allogeneic HSCT is required only in cases of refractoriness. A deeper knowledge of immunologic patterns contributing to HIS pathogenesis in ADA-SCID patients is desirable, to identify new targeted treatments and ensure patients' long-term recovery.

Diagnosis and management of neutropenia in children: The approach of the Study Group on Neutropenia and Marrow Failure Syndromes of the Pediatric Italian Hemato-Oncology Association (Associazione Italiana Emato-Oncologia Pediatrica - AIEOP).

Neutropenia refers to a group of diseases characterized by a reduction in neutrophil levels below the recommended age threshold. The present study aimed to review the diagnosis and management of neutropenia, including a diagnostic toolkit and candidate underlying genes. This study also aimed to review the progress toward the definition of autoimmune and idiopathic neutropenia rising in infancy or in late childhood but without remission, and provide suggestions for efficient diagnostics, including indications for the bone marrow and genetic testing. The management and treatment protocols for common and unique presentations are also reviewed, providing evidence tailored to a single patient.

Fatigue perception in a cohort of children with chronic immune thrombocytopenia and their caregivers using the PedsQL MFS: Real-life multicenter experience of the Italian Association of Pediatric Hematology and Oncology (AIEOP).

BACKGROUND: Fatigue is an important clinical and psychological aspect for a significant number of children affected by immune thrombocytopenia (ITP). To date, few studies have explored fatigue and its relationship with chronic ITP in pediatric age. The aim of the present multicentric pilot study is to determine fatigue perception in a large group of children with chronic ITP and their caregivers using the PedsQL Multidimensional Fatigue Scale (PedsQL MFS), and to compare the results with those of healthy control subjects. PROCEDURE: Children with chronic ITP aged 5-18 years and/or caregivers of children aged 2-18 years were enrolled. Child/adolescent self-report was used for patients aged 5-18 years, and parent proxy-report for patients aged 2-18 years. The questionnaire was offered as online survey. PedsQL MFS is composed of 18 items covering three dimensions: General Fatigue Scale, Sleep/Rest Fatigue Scale, and Cognitive Fatigue Scale. RESULTS: One hundred ninety-one patients affected by chronic ITP and 248 caregivers answered the PedsQL MFS. We have highlighted that lower values of PedsQL MFS scores are obtained in the 13-18 age group. Moreover, sleep/rest fatigue domain appears to be more compromised in all age groups. For all PedsQL MFS scores, pediatric patients with chronic ITP and their caregivers reported statistically significant worse fatigue than healthy children. CONCLUSIONS: This study suggests that fatigue is relevant among children and adolescents affected by chronic ITP. The PedsQL MFS represents an adequate instrument for measuring fatigue in patients with chronic ITP. Therefore, symptoms of fatigue should be routinely assessed in clinical practice.

Use of Eltrombopag in Children With Chronic Immune Thrombocytopenia (ITP): A Real Life Retrospective Multicenter Experience of the Italian Association of Pediatric Hematology and Oncology (AIEOP).

Background: The thrombopoietin receptor agonist eltrombopag has been shown to be safe and effective for children with chronic immune thrombocytopenia (ITP). The aim of the present study was to characterize eltrombopag use in current clinical practice. Material and Methods: This is a retrospective multicenter study conducted in 17 centers affiliated to the Italian Association of Pediatric Hematology and Oncology (AIEOP). The primary objective of the study was to determine the prevalence of eltrombopag use in Italian children affected by chronic ITP, after EMA authorization for pediatric age. The secondary objective was to assess efficacy in the first 6 months and safety during the whole period of eltrombopag treatment in current clinical practice. A total of 386 children with chronic ITP were retrospectively enrolled and eligible for analysis. Among these patients, 71 received eltrombopag. Results: The prevalence of eltrombopag use was 19% (95% CI 0.15-0.23). Thirty-one patients (44%) were male and 40 patients (56%) were female. The median age at the first dose of eltrombopag was 12 years (3-17 years). The median duration of eltrombopag treatment was 11 months (1-32 months) and the median starting dose was 50 mg/day (12, 5-75 mg/day). Thirty-two patients (45%) required one or more concomitant ITP medications during the first 6 months of treatment with eltrombopag. Thirty-nine patients (55%) never required concomitant medications. Median platelet counts and proportion of patients achieving the target platelet count of at least 30 × 109/L and 100 × 109/L significantly increased during the first 6 months of treatment (p < 0.0001). Additionally, eltrombopag has been proved effective in the absence of concomitant therapies. The most common Adverse Events were headache (7%) and thrombocytosis (6%). Conclusion: Our study highlighted the crucial role of eltrombopag as second line treatment in children with chronic ITP.

Monitoring oral iron therapy in children with iron deficiency anemia: an observational, prospective, multicenter study of AIEOP patients (Associazione Italiana Emato-Oncologia Pediatrica).

Oral ferrous salts are standard treatment for children with iron deficiency anemia (IDA). The objective of our study was to monitor oral iron therapy in children, aged 3 months-12 years, with IDA. We prospectively collected clinical and hematological data of children with IDA, from 15 AIEOP (Associazione Italiana di Ematologia ed. Oncologia Pediatrica) centers. Response was measured by the increase of Hb from baseline. Of the 107 analyzed patients, 18 received ferrous gluconate/sulfate 2 mg/kg (ferrous 2), 7 ferrous gluconate/sulfate 4 mg/kg (ferrous 4), 7 ferric iron salts 2 mg/kg (ferric), 62 bis-glycinate iron 0.45 mg/kg (glycinate), and 13 liposomal iron 0.7-1.4 mg/kg (liposomal). Increase in reticulocytes was evident at 3 days, while Hb increase appeared at 2 weeks. Gain of Hb at 2 and 8 weeks revealed a higher median increase in both ferrous 2 and ferrous 4 groups. Gastro-intestinal side effects were reported in 16% (ferrous 2), 14% (ferrous 4), 6% (glycinate), and 0 (ferric and liposomal) patients. The reticulocyte counts significantly increased after 3 days from the start of oral iron supplementation. Bis-glycinate iron formulation had a good efficacy/safety profile and offers an acceptable alternative to ferrous iron preparations.

Primary Immunodeficiencies and Oncological Risk: The Experience of the Children's Hospital of Brescia.

Background and aims: Primary immunodeficiencies (PID) are characterized by recurrent infections and increased risk of malignancies because of the reduced immunological surveillance against cancer cells and oncogenic viruses. Methods: We report the incidence of tumors among 690 patients with PID, diagnosed from 1990 until 2017 in Brescia. Results: Out of 690 patients, 25 patients (3.6%) developed 33 tumors. Of the 25 affected patients, 8 patients suffered from common variable immunodeficiency (CVID), 5 from combined immunodeficiency (CID), 3 from Ataxia-telangectasia (AT), 2 from Hermanksy-Pudlak type 2 (HSP2), 2 from gammaglobulinemia X-linked (XLA), 2 from Wiskott-Aldrich syndrome (WAS), 2 from Hyper IgE syndrome (HIES), 1 from severe combined immunodeficiency (SCID). The age at diagnosis ranged from 1 to 52 years, with a median age of 19.6 years. The time between the diagnosis of PID and onset of tumor was short, often <1 year between diagnosis and the appearance of cancer in the case of CID. Moreover, in two cases of CID, the diagnosis of cancer was made before the diagnosis of PID, so cancer was the onset clinical manifestation. Hematological malignancies were prevalent (22/33, 66.7%) with a minority of solid tumors (11/33, 33.33%). In particular Non-Hodgkin lymphomas were the most frequent (16/33, 48.48%). In total 13 patients survived (52%) and tumor was the main cause of death (7 cases). Two patients underwent BMT once the disease was in remission. Conclusions: Therefore, the correct management of tumors that arise in patients with primitive immunodeficiency still represents a challenge in the pediatric field. For this reason now it is mandatory to collect in a unique international registry the cases of malignancies in PID that could lead to a better understanding of the etiopathogenesis and of the biological and clinical characteristics of these tumors, with the aim of defining adequate preventive measures and guaranteeing an early diagnosis which also creating a shared and specific therapeutic strategy, with the prospect of obtaining a better prognosis for these patients.

Congenital Hypopigmentary Disorders with Multiorgan Impairment: A Case Report and an Overview on Gray Hair Syndromes.

The term congenital hypopigmentary disorders refers to a wide group of heterogeneous hereditary diseases, clinically characterized by inborn pigmentary defects of the iris, hair, and/or skin. They include Gray Hair Syndromes (GHSs), a rare group of autosomal recessive genodermatosis hallmarked by inborn silvery gray hair. GHSs encompass Griscelli, Chediak⁻Higashi, Elejalde, and Cross syndromes, which are all characterized by a broad spectrum of severe multisystem disorders, including neurological, ocular, skeletal, and immune system impairment. In this manuscript, we describe in detail the clinical, trichoscopic, and genetic features of a rare case of Griscelli syndrome; moreover, we provide an overview of all the GHSs known to date. Our report highlights how an accurate clinical examination with noninvasive methods, like trichoscopy, may play a crucial rule in diagnosis of rare and potentially lethal genetic syndromes such as Griscelli syndrome, in which timely diagnosis and therapy may modify the clinical course, quality of life, and likelihood of survival.

Lentiviral gene therapy corrects platelet phenotype and function in patients with Wiskott-Aldrich syndrome.

BACKGROUND: Thrombocytopenia is a serious issue for all patients with classical Wiskott-Aldrich syndrome (WAS) and X-linked thrombocytopenia (XLT) because it causes severe and life-threatening bleeding. Lentiviral gene therapy (GT) for WAS has shown promising results in terms of immune reconstitution. However, despite the reduced severity and frequency of bleeding events, platelet counts remain low in GT-treated patients. OBJECTIVE: We carefully investigated platelet defects in terms of phenotype and function in untreated patients with WAS and assessed the effect of GT treatment on platelet dysfunction. METHODS: We analyzed a cohort of 20 patients with WAS/XLT, 15 of them receiving GT. Platelet phenotype and function were analyzed by using electron microscopy, flow cytometry, and an aggregation assay. Platelet protein composition was assessed before and after GT by means of proteomic profile analysis. RESULTS: We show that platelets from untreated patients with WAS have reduced size, abnormal ultrastructure, and a hyperactivated phenotype at steady state, whereas activation and aggregation responses to agonists are decreased. GT restores platelet size and function early after treatment and reduces the hyperactivated phenotype proportionally to WAS protein expression and length of follow-up. CONCLUSIONS: Our study highlights the coexistence of morphologic and multiple functional defects in platelets lacking WAS protein and demonstrates that GT normalizes the platelet proteomic profile with consequent restoration of platelet ultrastructure and phenotype, which might explain the observed reduction of bleeding episodes after GT. These results are instrumental also from the perspective of a future clinical trial in patients with XLT only presenting with microthrombocytopenia.

Cerebellar involvement in warts Hypogammaglobulinemia immunodeficiency myelokathexis patients: neuroimaging and clinical findings.

BACKGROUND: Warts Hypogammaglobulinemia Immunodeficiency Myelokathexis (WHIM) syndrome is a primary immunodeficiency characterized by recurrent bacterial infections, severe chronic neutropenia, with lymphopenia, monocytopenia and myelokathexis which is caused by heterozygous gain of functions mutations of the CXC chemokine receptor 4 (CXCR4). WHIM patients display an increased incidence of non-hematopoietic conditions, such as congenital heart disease suggesting that abnormal CXCR4 may put these patients at increased risk of congenital anomalies. Studies conducted on CXCR4 and SDF-1-deficient mice have demonstrated the role of CXCR4 signaling in neuronal cell migration and brain development. In particular, CXCR4 conditional knockout mice display abnormal cerebellar morphology and poor coordination and balance on motor testing. RESULTS: In order to evaluate a possible neurological involvement in WHIM syndrome subjects, we performed neurological examination, including International Cooperative Ataxia Rating Scale, cognitive and psychopathological assessment and brain Magnetic Resonance Imaging (MRI) in 6 WHIM patients (age range 8-51 years) with typical gain of functions mutations of CXCR4 (R334X or G336X). In three cases (P3, P5, P6) neurological evaluation revealed fine and global motor coordination disorders, balance disturbances, mild limb ataxia and excessive talkativeness. Brain MRI showed an abnormal orientation of the cerebellar folia involving bilaterally the gracilis and biventer lobules together with the tonsils in four subjects (P3, P4, P5, P6). The neuropsychiatric evaluation showed increased risk of internalizing and/or externalizing problems in four patients (P2, P3, P4, P6). CONCLUSIONS: Taken together, these observations suggest CXCR4 gain of function mutations can be associated with cerebellar malformation, mild neuromotor and psychopathological dysfunction in WHIM patients.

Long-Term Outcome of WHIM Syndrome in 18 Patients: High Risk of Lung Disease and HPV-Related Malignancies.

BACKGROUND: In the warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome, variable phenotypic expression may delay diagnosis. Panleukopenia, malignancy, and chronic lung disease all affect morbidity and mortality risks. Routinely used treatments include immunoglobulins, granulocyte-colony stimulating factor (G-CSF), and antibiotics; recent trials with a target C-X-C chemokine receptor type 4 (CXCR4) antagonist show promising results. OBJECTIVE: We sought to characterize the largest cohort of patients with WHIM and evaluate their diagnostic and therapeutic management. METHODS: Data were collected from an international cohort of 18 patients with CXCR4 mutations. RESULTS: The clinical features manifested at 2.2 ± 2.6 years of age, whereas the disease diagnosis was delayed until 12.5 ± 10.4 years of age. Patients with WHIM commonly presented with a severe bacterial infection (78%). Pneumonia recurrence was observed in 61% of patients and was complicated with bronchiectasis in 27%. Skin warts were observed in 61% of patients at a mean age of 11 years, whereas human papilloma virus (HPV)-related malignancies manifested in 16% of patients. All the patients had severe neutropenia (195 ± 102 cells/mm3 at onset), whereas lymphopenia and hypogammaglobulinemia were detected in 88% and 58% of patients, respectively. Approximately 50% of patients received antibiotic prophylaxis, whereas G-CSF and immunoglobulin treatments were used in 72% and 55% of patients, respectively. CONCLUSIONS: The WHIM syndrome onsets early in life and should be suspected in patients with chronic neutropenia. Patients with WHIM need careful monitoring and timely intervention for complications, mainly lung disease and HPV-related malignancies. We suggest that immunoglobulin therapy should be promptly considered to control the frequency of bacterial infections and prevent chronic lung damage.

Role of antithyroid autoimmunity as a predictive biomarker of chronic immune thrombocytopenia.

BACKGROUND: Immune thrombocytopenia (ITP) is an acquired immune-mediated disorder characterized by isolated thrombocytopenia. Pediatric ITP patients are prone to develop autoantibodies such as antithyroglobulin (TG) and antithyroperoxidase (TPO), even in the absence of clinical signs of autoimmune disease. The aim of this multicenter retrospective study was to evaluate (1) the prevalence of positivity of antithyroid antibodies (TPO and TG) in a large cohort of pediatric patients with chronic ITP; (2) the role of autoimmune thyroiditis as a prognostic factor for chronicity of ITP. PROCEDURE: For this retrospective study, we collected data from patients diagnosed as affected by chronic ITP between 2011 and 2014 in six centers belonging to the Italian Association of Pediatric Haematology and Oncology (AIEOP). RESULTS: From the analysis of data, we found a significantly higher prevalence of antithyroid antibodies in children with chronic ITP (11.6%) than in the pediatric population (1.2%-1.3%). No correlation has been found between the platelet count and the prevalence of positive antithyroid antibodies at any detection time of the study. CONCLUSIONS: The results of our study demonstrated that (1) the prevalence of positivity for antithyroid antibodies (anti-TPO and anti-TG) in pediatric patients with chronic ITP results is significantly higher than in the pediatric population; (2) autoimmune thyroiditis does not seem to play a role as a prognostic factor for chronicity of ITP in pediatric patients.

Idiopathic neutropenia of infancy: Data from the Italian Neutropenia Registry.

Autoimmune neutropenia of infancy (AIN) is characterized by low risk of severe infection, tendency to spontaneously resolve and typically onset at ≤4-5 years of age; it is due to auto-antibodies whose detection is often difficult. In case of negativity of 4 antineutrophils autoantibody tests, after having excluded ethnic, postinfection, drug induced, or congenital neutropenia, according to the Italian guidelines the patients will be defined as affected by "idiopathic neutropenia" (IN). We describe the characteristics of 85 IN patients enrolled in the Italian neutropenia registry: they were compared with 336 children affected by AIN. The 2 groups were clinically very similar and the main differences were detection age (later in IN), length of disease (longer in IN) and, among recovered patients, age of spontaneous recovery: the median age at resolution was 2.13 years in AINs and 3.03 years in INs (P = .00002). At bivariate analysis among AIN patients earlier detection age (P = .00013), male sex (P = .000748), absence of leucopenia (P = .0045), and absence of monocytosis (P = .0419) were significantly associated with earlier recovery; in the IN group only detection age (P = .013) and absence of monocytosis (P = .0333) were significant. At multivariate analysis detection age and absence of monocytosis were independently significant (P = 6.7e-05 and 4.4e-03, respectively) in the AIN group, whereas in the IN group only detection age stayed significant (P = .013).

Long term outcome of eight patients with type 1 Leukocyte Adhesion Deficiency (LAD-1): Not only infections, but high risk of autoimmune complications.

Leukocyte Adhesion Deficiency type 1 (LAD-1) is a rare primary immunodeficiency due to mutations in the gene encoding for the common ß-chain of the ß2 integrin family (CD18). Herein, we describe clinical manifestations and long-term complications of eight LAD-1 patients. Four LAD-1 patients were treated with hematopoietic stem cell transplantation (HSCT), while the remaining four, including two with moderate LAD-1 deficiency, received continuous antibiotic prophylaxis. Untreated patients presented numerous infections and autoimmune manifestations. In particular, two of them developed renal and intestinal autoimmune diseases, despite the expression of Beta-2 integrin was partially conserved. Other two LAD-1 patients developed type 1 diabetes and autoimmune cytopenia after HSCT, suggesting that HSCT is effective for preventing infections in LAD-1, but does not prevent the risk of the autoimmune complications.

Maternal T-cell engraftment impedes with diagnosis of a SCID-ADA patient.

We describe the case of a child affected by severe combined immunodeficiency (SCID) with adenosine deaminase (ADA) deficiency showing a maternal T-cell engraftment, a finding that has never been reported before. The presence of engrafted maternal T cells was misleading. Although ADA enzymatic levels were suggestive of ADA-SCID, the child did not present the classical signs of ADA deficiency; therefore, the initial diagnosis was of a conventional SCID. However, ADA toxic metabolites and molecular characterization confirmed this diagnosis. Polyethylene glycol-modified bovine (PEG) ADA therapy progressively decreased the number of maternal engrafted T cells. The child was grafted with full bone marrow from a matched unrelated donor, after a reduced conditioning regimen, and the result was the complete immunological reconstitution.

Long-term follow-up of IPEX syndrome patients after different therapeutic strategies: An international multicenter retrospective study.

BACKGROUND: Immunodysregulation polyendocrinopathy enteropathy x-linked (IPEX) syndrome is a monogenic autoimmune disease caused by FOXP3 mutations. Because it is a rare disease, the natural history and response to treatments, including allogeneic hematopoietic stem cell transplantation (HSCT) and immunosuppression (IS), have not been thoroughly examined. OBJECTIVE: This analysis sought to evaluate disease onset, progression, and long-term outcome of the 2 main treatments in long-term IPEX survivors. METHODS: Clinical histories of 96 patients with a genetically proven IPEX syndrome were collected from 38 institutions worldwide and retrospectively analyzed. To investigate possible factors suitable to predict the outcome, an organ involvement (OI) scoring system was developed. RESULTS: We confirm neonatal onset with enteropathy, type 1 diabetes, and eczema. In addition, we found less common manifestations in delayed onset patients or during disease evolution. There is no correlation between the site of mutation and the disease course or outcome, and the same genotype can present with variable phenotypes. HSCT patients (n = 58) had a median follow-up of 2.7 years (range, 1 week-15 years). Patients receiving chronic IS (n = 34) had a median follow-up of 4 years (range, 2 months-25 years). The overall survival after HSCT was 73.2% (95% CI, 59.4-83.0) and after IS was 65.1% (95% CI, 62.8-95.8). The pretreatment OI score was the only significant predictor of overall survival after transplant (P = .035) but not under IS. CONCLUSIONS: Patients receiving chronic IS were hampered by disease recurrence or complications, impacting long-term disease-free survival. When performed in patients with a low OI score, HSCT resulted in disease resolution with better quality of life, independent of age, donor source, or conditioning regimen.

Diagnostic value of cell bound and circulating neutrophil antibody detection in pediatric neutropenia.

BACKGROUND: Chronic benign neutropenia of infancy includes primary autoimmune neutropenia (pAIN) and chronic idiopathic neutropenia (CIN). A diagnosis of CIN is supported by the absence of free and/or cell-bound neutrophil autoantibodies, which can be detected by flow cytometry with the indirect-granulocyte immunofluorescence test (I-GIFT) and direct-granulocyte immunofluorescence test (D-GIFT), respectively. Conclusive evidence is lacking on the diagnostic value of the D-GIFT, whose performance requires specific laboratory expertise, may be logistically difficult, and hampered by very low neutrophil count in patient samples. This study investigated whether the evaluation of D-GIFT improves the diagnostic accuracy of pediatric neutropenia. PROCEDURE: I-GIFT and D-GIFT were performed in 174 pAIN, 162 CIN, 81 secondary AIN, 51 postinfection neutropenic, and 65 nonautoimmune neutropenic children referred to this laboratory during 2002-2014. RESULTS: Using 90% specific median fluorescence intensity cut-off values calculated by receiver operating characteristic curves, D-GIFT was positive in 49% of CIN patients, who showed similar clinical features as those with pAIN. In 44 (27%) of 162 CIN patients, I-GIFT was repeated two to three times in a year, resulting positive in 12 and two patients at second and third screening, respectively. Interestingly, 10 of the latter 14 patients showed a positive D-GIFT at the first serological screening. False positive D-GIFT was shown by 12% and 22% of nonneutropenic and nonautoimmune neutropenic patients, respectively. CONCLUSIONS: D-GIFT evaluation improves the diagnostic accuracy of pediatric neutropenia, but improvement of cell-bound antibody detection is needed to decrease false positive results.