Quality of Life of Patients with Wiskott Aldrich Syndrome and X-Linked Thrombocytopenia: a Study of the Primary Immune Deficiency Consortium (PIDTC), Immune Deficiency Foundation, and the Wiskott-Aldrich Foundation

Health-related quality of life in patients with inborn errors of immunity: A systematic review and meta-analysis

BACKGROUND

Inborn Errors of Immunity (IEI) significantly affect patients' health-related quality of life (HRQOL), presenting greater challenges than those faced by the healthy population and other chronic disease sufferers. Current research lacks comprehensive integration of this critical issue.

OBJECTIVE

This study explores HRQOL in IEI patients, identifies impacting factors, and advocates for increased research focus on their quality of life.

METHODS

Following systematic review and meta-analysis guidelines, a search of Scopus and PubMed until November 15, 2023, yielded 1633 publications. We evaluated the literature, assessed study quality, and compared the HRQOL of IEI patients to that of healthy individuals and other chronic disease patients.

RESULTS

Of 90 articles and 10,971 IEI patients analyzed, study quality varied (nine good, 63 moderate, and 18 poor). The Short Form-36 (SF-36) and Pediatric Quality of Life Inventory generic core scales (PedsQL) were the primary generic instruments used among adults and children, respectively, with 12 studies each using the disease-specific instruments. Meta-analysis showed IEI patients have significantly lower scores in general health, physical and mental health, and social and emotional roles compared to healthy populations. We noted significant differences between self and proxy reports, indicating caregiver anxiety and perception disparities.

CONCLUSION

Despite limitations like small sample sizes and reliance on generic instruments, this research underscores the substantially lower HRQOL among IEI patients, emphasizing the need for a patient-centered, multidisciplinary approach to improve their life quality and calling for more focused attention on IEI patients and their caregivers' HRQOL.

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.

Too much of a good thing: a review of primary immune regulatory disorders

Primary immune regulatory disorders (PIRDs) are inborn errors of immunity caused by a loss in the regulatory mechanism of the inflammatory or immune response, leading to impaired immunological tolerance or an exuberant inflammatory response to various stimuli due to loss or gain of function mutations. Whilst PIRDs may feature susceptibility to recurrent, severe, or opportunistic infection in their phenotype, this group of syndromes has broadened the spectrum of disease caused by defects in immunity-related genes to include autoimmunity, autoinflammation, lymphoproliferation, malignancy, and allergy; increasing focus on PIRDs has thus redefined the classical 'primary immunodeficiency' as one aspect of an overarching group of inborn errors of immunity. The growing number of genetic defects associated with PIRDs has expanded our understanding of immune tolerance mechanisms and prompted identification of molecular targets for therapy. However, PIRDs remain difficult to recognize due to incomplete penetrance of their diverse phenotype, which may cross organ systems and present to multiple clinical specialists prior to review by an immunologist. Control of immune dysregulation with immunosuppressive therapies must be balanced against the enhanced infective risk posed by the underlying defect and accumulated end-organ damage, posing a challenge to clinicians. Whilst allogeneic hematopoietic stem cell transplantation may correct the underlying immune defect, identification of appropriate patients and timing of transplant is difficult. The relatively recent description of many PIRDs and rarity of individual genetic entities that comprise this group means data on natural history, clinical progression, and treatment are limited, and so international collaboration will be needed to better delineate phenotypes and the impact of existing and potential therapies. This review explores pathophysiology, clinical features, current therapeutic strategies for PIRDs including cellular platforms, and future directions for research.

Health-Related Quality of Life of Patients and Families with Primary Immunodeficiency in Malaysia: a Cross-Sectional Study

PURPOSE

Primary immunodeficiency disease (PID) affects various aspects of a patient's life. However, the health-related quality of life (HRQOL) of PID among Malaysian patients is poorly described. This study aimed to determine the quality of life of PID patients and their respective parents.

METHOD

This cross-sectional study was performed from August 2020 to November 2020. Patients with PID and their families were invited to answer the PedsQL Malay version (4.0) questionnaire, the tool used to assess the HRQOL. A total of 41 families and 33 patients with PID answered the questionnaire. A comparison was performed with the previously published value of healthy Malaysian children.

RESULT

Parents of respondents recorded a lower mean of total score than the parents of healthy children (67.26 ± 16.73 vs. 79.51 ± 11.90, p-value = 0.001, respectively). PID patients reported lower mean total score to healthy children (73.68 ± 16.38 vs. 79.51 ± 11.90, p-value = 0.04), including the psychosocial domain (71.67 ± 16.82 vs. 77.58 ± 12.63, p-value = 0.05) and school functioning (63.94 ± 20.87 vs. 80.00 ± 14.40, p-value = 0.007). No significant difference of reported HRQOL when comparing between subgroup of PID on immunoglobulin replacement therapy and those without immunoglobulin replacement (56.96 ± 23.58 vs. 65.83 ± 23.82, p-value 0.28). Socioeconomic status was found to be predictive of the lower total score of PedsQL in both parent and children reports.

CONCLUSION

Parents and children with PID, especially those from middle socioeconomic status, have lower HRQOL and school function impairment than healthy children.

Síndrome de Wiskott-Aldrich en España: incidencia, mortalidad y sesgo de género durante 21 años

Antecedentes

El síndrome de Wiskott-Aldrich (SWA) es un raro trastorno ligado al cromosoma X que se considera que afecta predominantemente a varones.

Objetivo

El objetivo de este estudio consistía en investigar la incidencia y la mortalidad intrahospitalaria del SWA en España, así como el sesgo de género.

Métodos

Se llevó a cabo un estudio epidemiológico retrospectivo poblacional en 97 pacientes con SWA diagnosticados en hospitales españoles entre 1997 y 2017, utilizando para ello datos del Sistema Nacional de Vigilancia de Datos Hospitalarios.

Resultados

Nuestros resultados revelaron que la incidencia anual media del SAW en España fue de 1,1 caso por cada 10 millones de habitantes (IC del 95 %, 0,45-2,33). El riesgo relativo fue mayor en los varones que en las mujeres (2,42). El diagnóstico de SWA se establece a una edad más avanzada en las mujeres (mediana de 47 años) que en los varones (mediana de 5,5 años). Únicamente los varones ingresaron en el hospital en al menos 10 ocasiones diferentes y todas las muertes se detectaron en varones. La tasa de mortalidad intrahospitalaria fue del 9,28 % en el SAW y la mayoría de las muertes se asociaron a hemorragia cerebral o infección.

Conclusiones

El SWA, una enfermedad rara, se diagnostica a una edad más avanzada en las mujeres y la mortalidad se observó exclusivamente en varones, asociada en la mayoría de los casos a hemorragia cerebral e infección.

Congenital Athymia: Unmet Needs and Practical Guidance

Inborn errors of thymic stromal cell development and function which are associated with congenital athymia result in life-threatening immunodeficiency with susceptibility to infections and autoimmunity. Athymic patients can be treated by thymus transplantation using cultured donor thymus tissue. Outcomes in patients treated at Duke University Medical Center and Great Ormond Street Hospital (GOSH) over the past three decades have shown that sufficient T-cell immunity can be recovered to clear and prevent infections, but post-treatment autoimmune manifestations are relatively common. Whilst thymus transplantation offers the chance of long-term survival, significant challenges remain to optimise the outcomes for the patients. In this review, we will discuss unmet needs and offer practical guidance based on the experience of the European Thymus Transplantation programme at GOSH. Newborn screening (NBS) for severe combined immunodeficiency (SCID) and routine use of next-generation sequencing (NGS) platforms have improved early recognition of congenital athymia and increasing numbers of patients are being referred for thymus transplantation. Nevertheless, there remain delays in diagnosis, in particular when the cause is genetically undefined, and treatment accessibility needs to be improved. The majority of athymic patients have syndromic features with acute and chronic complex health issues, requiring life-long multidisciplinary and multicentre collaboration to optimise their medical and social care. Comprehensive follow up after thymus transplantation including monitoring of immunological results, management of co-morbidities and patient and family quality-of-life experience, is vital to understanding long-term outcomes for this rare cohort of patients. Alongside translational research into improving strategies for thymus replacement therapy, patient-focused clinical research will facilitate the design of strategies to improve the overall care for athymic patients.

Hematopoietic stem cell transplantation for adolescents and adults with inborn errors of immunity: an EBMT IEWP study

Allogeneic hematopoietic stem cell transplantation (HSCT) is the gold standard curative therapy for infants and children with many inborn errors of immunity (IEI), but adolescents and adults with IEI are rarely referred for transplant. Lack of published HSCT outcome data outside small, single-center studies and perceived high risk of transplant-related mortality have delayed the adoption of HSCT for IEI patients presenting or developing significant organ damage later in life. This large retrospective, multicenter HSCT outcome study reports on 329 IEI patients (age range, 15-62.5 years at HSCT). Patients underwent first HSCT between 2000 and 2019. Primary endpoints were overall survival (OS) and event-free survival (EFS). We also evaluated the influence of IEI-subgroup and IEI-specific risk factors at HSCT, including infections, bronchiectasis, colitis, malignancy, inflammatory lung disease, splenectomy, hepatic dysfunction, and systemic immunosuppression. At a median follow-up of 44.3 months, the estimated OS at 1 and 5 years post-HSCT for all patients was 78% and 71%, and EFS was 65% and 62%, respectively, with low rates of severe acute (8%) or extensive chronic (7%) graft-versus-host disease. On univariate analysis, OS and EFS were inferior in patients with primary antibody deficiency, bronchiectasis, prior splenectomy, hepatic comorbidity, and higher hematopoietic cell transplant comorbidity index scores. On multivariable analysis, EFS was inferior in those with a higher number of IEI-associated complications. Neither age nor donor had a significant effect on OS or EFS. We have identified age-independent risk factors for adverse outcome, providing much needed evidence to identify which patients are most likely to benefit from HSCT.

Diagnosis and clinical management of Wiskott-Aldrich syndrome: current and emerging techniques

INTRODUCTION

Wiskott-Aldrich syndrome (WAS) serves as the prototype of how variants in a gene which encodes a protein central to actin cytoskeletal homeostasis can manifest clinically in a variety of ways including infection, atopy, autoimmunity, inflammation, bleeding, neutropenia, non-malignant lymphoproliferation, and malignancy. Despite the discovery of the WAS gene almost 30 years ago, our understanding of the pathophysiological mechanisms underlying WAS continues to unfold.

AREAS COVERED

This review will provide an overview of the approach to the diagnosis of WAS as well as the management of its associated complications. Advances in the use of allogeneic hematopoietic stem cell transplantation (HSCT) and gene therapy as well as the associated challenges unique to WAS will be discussed.

EXPERT OPINION

Basic research, combined with clinical research focusing on longitudinal analysis of WAS patients, will help clarify determinants that influence WAS pathogenesis as well as clinical complications and outcomes. Advances in curative approaches including the use of alternative donor HSCT for WAS continue to evolve. Gene therapy employing safer and more effective protocols ensuring full correction of WAS will provide life-saving benefit to WAS patients that are unable to undergo HSCT.

Hematopoietic stem cell transplantation for Wiskott-Aldrich syndrome: an EBMT inborn errors working party analysis

Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for patients affected by Wiskott-Aldrich syndrome (WAS). Reported HSCT outcomes have improved over time with respect to overall survival, but some studies have identified older age and HSCT from alternative donors as risk factors predicting poorer outcome. We analyzed 197 patients transplanted at EBMT centers between 2006 and 2017, who received conditioning as recommended by the inborn errors working party (IEWP): either busulfan (n=103) or treosulfan (n=94) combined with fludarabine ± thiotepa. After a median follow-up after HSCT of 44.9 months, 176 patients were alive, resulting in a 3-year overall survival of 88.7%, and chronic GVHD-free survival (CRFS; events: death, graft failure, severe chronic GVHD) of 81.7%. Overall survival and CRFS were not significantly impacted by conditioning regimen (busulfan- versus treosulfan-based), donor type (MSD/MFD vs MUD/MMUD vs. MMFD), and period of HSCT (2006-2013 vs. 2014-2017). Patients younger than 5 years at HSCT had a significantly better overall survival. The overall cumulative incidences of grade III-IV acute GVHD and extensive/moderate/severe chronic GVHD were 6.6% and 2.1%, respectively. Patients receiving treosulfan-based conditioning had a higher incidence of graft failure, mixed donor chimerism and more frequently received secondary procedures (2nd HSCT, unconditioned stem cell boost, donor lymphocyte infusion, or splenectomy). In summary, HSCT for WAS with conditioning regimens currently recommended by IEWP results in excellent survival and low rates of GVHD, regardless of donor or stem cell source, but age ≥5 years remains a risk factor for overall survival.

Being the Pillar for Children with Rare Diseases-A Systematic Review on Parental Quality of Life

Parents caring for children with rare diseases fear the long-term progression of the child's disease. The current study aims to systematically investigate the quality of life (QoL) in parents of children with different rare diseases. We performed a systematic literature search including quantitative studies on QoL of parents caring for children and adolescents with rare diseases in five databases (APA PsycArticles, APA PsycInfo, MEDLINE, PSYNDEXplus, and PubMed) published between 2000-2020. Of the 3985 titles identified, 31 studies met the inclusion criteria and were selected for narrative review. Studies were included if they investigated predictors of parental QoL or reported QoL compared to normative samples, parents of healthy children, or children with other chronic diseases. We used the Newcastle-Ottawa Scale to assess methodological quality. The systematic review revealed that parents of children with rare diseases experience reduced QoL compared to parents with healthy children and norm values. Psychosocial factors, beyond disease-specific predictors, were shown to influence parental QoL substantially and may thus present an essential aspect within interventions for this highly burdened group. Health care professionals should consider and address the impairment of parental QoL due to the child's rare disease. We discuss insights into existing research gaps and improvements for subsequent work.

Excellent outcomes following hematopoietic cell transplantation for Wiskott-Aldrich syndrome: a PIDTC report

Wiskott-Aldrich syndrome (WAS) is an X-linked disease caused by mutations in the WAS gene, leading to thrombocytopenia, eczema, recurrent infections, autoimmune disease, and malignancy. Hematopoietic cell transplantation (HCT) is the primary curative approach, with the goal of correcting the underlying immunodeficiency and thrombocytopenia. HCT outcomes have improved over time, particularly for patients with HLA-matched sibling and unrelated donors. We report the outcomes of 129 patients with WAS who underwent HCT at 29 Primary Immune Deficiency Treatment Consortium centers from 2005 through 2015. Median age at HCT was 1.2 years. Most patients (65%) received myeloablative busulfan-based conditioning. With a median follow-up of 4.5 years, the 5-year overall survival (OS) was 91%. Superior 5-year OS was observed in patients <5 vs ≥5 years of age at the time of HCT (94% vs 66%; overall P = .0008). OS was excellent regardless of donor type, even in cord blood recipients (90%). Conditioning intensity did not affect OS, but was associated with donor T-cell and myeloid engraftment after HCT. Specifically, patients who received fludarabine/melphalan-based reduced-intensity regimens were more likely to have donor myeloid chimerism <50% early after HCT. In addition, higher platelet counts were observed among recipients who achieved full (>95%) vs low-level (5%-49%) donor myeloid engraftment. In summary, HCT outcomes for WAS have improved since 2005, compared with prior reports. HCT at a younger age continues to be associated with superior outcomes supporting the recommendation for early HCT. High-level donor myeloid engraftment is important for platelet reconstitution after either myeloablative or busulfan-containing reduced intensity conditioning. (This trial was registered at www.clinicaltrials.gov as #NCT02064933.).