Clinical outcome in children with chronic granulomatous disease managed conservatively or with hematopoietic stem cell transplantation

Inborn errors of immunity and invasive fungal infections: presentation and management

PURPOSE OF REVIEW

We review the clinical presentations of invasive fungal infections in a selection of inborn errors of immunity. In addition, we review the particularities of their management, including antifungal therapy, prophylaxis, and immunomodulatory treatments.

RECENT FINDINGS

Patients with chronic granulomatous disease and with signal transducer and activator of transcription 3 (STAT3) deficiency are particularly prone to aspergillosis. Mold-active antifungal prophylaxis should be prescribed to all patients with chronic granulomatous disease, and in patients with STAT3 deficiency and underlying parenchymal lung disease. Invasive fungal infections are rare in patients with STAT1 gain-of-function mutations, while the clinical phenotype of caspase-associated recruitment domain-containing protein 9 deficiency encompasses a wide range of superficial and invasive fungal infections. Most patients with inborn errors of immunity and invasive fungal infections require prolonged durations of antifungals. Hematopoietic stem cell transplantation should be considered early for patients with chronic granulomatous disease, but results have been more mixed for other inborn errors of immunity with active invasive fungal infections.

SUMMARY

Inborn errors of immunity can confer increased susceptibility to a variety of invasive fungal infections, which can present with specific clinical and radiological features. Management of fungal infections in these patients is often challenging, and relies on a combination of antimicrobial prophylaxis, antifungal treatments, and immunomodulation.

Clinical presentation, diagnosis, and treatment of chronic granulomatous disease

Chronic granulomatous disease (CGD) is caused by an impaired respiratory burst reaction in phagocytes. CGD is an X-linked (XL) (caused by pathogenic variants in CYBB) or autosomal recessive inborn error of immunity (caused by pathogenic variants in CYBA, NCF1, NCF2, or CYBC1). Female carriers of XL-CGD and unfavorable lyonization may present with the partial or full picture of CGD. Patients with CGD are at increased risk for invasive bacterial and fungal infections of potentially any organ, but especially the lymph nodes, liver, and lungs. Pathogens most frequently isolated are S. aureus and Aspergillus spp. Autoinflammation is difficult to control with immunosuppression, and patients frequently remain dependent on steroids. To diagnose CGD, reactive oxygen intermediates (O2 - or H2O2) generated by the NADPH oxidase in peripheral blood phagocytes are measured upon in vitro activation with either phorbol-12-myristate-13-acetate (PMA) and/or TLR4 ligands (E. coli or LPS). Conservative treatment requires strict hygienic conduct and adherence to antibiotic prophylaxis against bacteria and fungi, comprising cotrimoxazole and triazoles. The prognosis of patients treated conservatively is impaired: for the majority of patients, recurrent and/or persistent infections, autoinflammation, and failure to thrive remain lifelong challenges. In contrast, cellular therapies (allogeneic stem cell transplantation or gene therapy) can cure CGD. Optimal outcomes in cellular therapies are observed in individuals without ongoing infections or inflammation. Yet cellular therapies are the only curative option for patients with persistent fungal infections or autoinflammation.

An Ethical Framework for Allergy and Immunology

Ethical dilemmas routinely occur in the clinical practice of allergy and immunology. These ethical questions stem from the range of conditions and the different populations cared for by Allergists/Immunologists. Hence, medical ethics is not an esoteric concept, but a practical skill physicians exercise regularly. Moreover, an ethics-centered approach may improve patient safety and outcomes. This article describes key principles of bioethics and illustrates an ethical framework that physicians can use in their conversations with patients. Utilization of this ethical framework is demonstrated through applying it to 4 unique clinical scenarios encountered by Allergists/Immunologists from different practice settings. The ethical framework for allergy and immunology is a technique to navigate ethically complex decisions that arise in routine clinical practice.

Inborn Errors of Immunity and Cytokine Storm Syndromes

Inborn errors of immunity (IEI) are a diverse and growing category of more than 430 chronic disorders that share susceptibilities to infections. Whether the result of a genetic lesion that causes defective granule-dependent cytotoxicity, excessive lymphoproliferation, or an overwhelming infection represents a unique antigenic challenge, IEIs can display a proclivity for cytokine storm syndrome (CSS) development. This chapter provides an overview of CSS pathophysiology as it relates to IEIs. For each IEI, the immunologic defect and how it promotes or discourages CSS phenomena are reviewed. The IEI-associated molecular defects in pathways that are postulated to be critical to CSS physiology (i.e., toll-like receptors, T regulatory cells, the IL-12/IFNγ axis, IL-6) and, whenever possible, review strategies for treating CSS in IEI patients with molecularly directed therapies are highlighted.

Allogeneic HSCT for Symptomatic Female X-linked Chronic Granulomatous Disease Carriers

X-linked chronic granulomatous disease (XL-CGD) is an inherited disorder of superoxide production, causing failure to generate the oxidative burst in phagocytes. It is characterized by invasive bacterial and fungal infections, inflammation, and chronic autoimmune disease. While XL-CGD carriers were previously assumed to be healthy, a range of clinical manifestations with significant morbidity have recently been described in a subgroup of carriers with impaired neutrophil oxidative burst due to skewed lyonization. Allogeneic hematopoietic stem cell transplantation (HSCT) is the standard curative treatment for CGD but has rarely been reported in individual symptomatic carriers to date. We undertook a retrospective international survey of outcome of HSCT for symptomatic XL-CGD carriers. Seven symptomatic female XL-CGD carriers aged 1-56 years underwent HSCT in four centers, indicated for severe and recurrent infection, colitis, and autoimmunity. Two patients died from transplant-related complications, following donor engraftment and restoration of oxidative burst. All surviving patients demonstrated resolution of their neutrophil oxidative burst defect with concordant reduction in infection and inflammatory symptoms and freedom from further immunosuppressive therapy. In conclusion, allogeneic HSCT may cure the phagocyte defect in symptomatic XL-CGD carriers and improve their recurrent and disabling infective and inflammatory symptoms but risks transplant-related complications.

Haematopoietic Stem Cell Transplantation for Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) is an inborn error of immunity due to defects in the transport or function of subunits of nicotinamide adenine dinucleotide phosphate oxidase, the enzyme that generates the phagocyte respiratory burst responsible for intracellular killing of engulfed micro-organisms. Patients present with infectious or inflammatory complications. Common bacterial pathogens include Staphylococcus aureus and Burkholderia cepacia complex. Fungal pathogens include Aspergillus species, particularly Aspergillus fumigatus. Inflammatory complications most commonly manifest as inflammatory bowel disease or lung disease. Granulomata are the distinguishing histological feature. Haematopoietic stem cell transplantation (HSCT) was first considered for CGD in the early 1970's. Since then, refinements in transplant technique, donor selection, conditioning regimens, and graft engineering have widened the option of HSCT to most patients with CGD. This review charts the progress made in HSCT for CGD.

Guardians of Immunity: Advances in Primary Immunodeficiency Disorders and Management

Primary immunodeficiency disorders (PIDs) are a heterogeneous group of genetic conditions profoundly impacting immune function. The investigation spans various PID categories, offering insights into their distinct pathogenic mechanisms and clinical manifestations. Within the adaptive immune system, B-cell, T-cell, and combined immunodeficiencies are dissected, emphasizing their critical roles in orchestrating effective immune responses. In the realm of the innate immune system, focus is directed toward phagocytes and complement deficiencies, underscoring the pivotal roles of these components in initial defense against infections. Furthermore, the review delves into disorders of immune dysregulation, encompassing hemophagocytic lymphohistiocytosis (HLH), autoimmune lymphoproliferative syndrome (ALPS), immune dysregulation, polyendocrinopathy, enteropathy, and X-linked(IPEX), and autoimmunity polyendocrinopathy candidiasis-ectodermal dystrophy(APECED), elucidating the intricate interplay between immune tolerance and autoimmunity prevention. Diagnostic strategies for PIDs are explored, highlighting advancements in genetic and molecular techniques that enable precise identification of underlying genetic mutations and alterations in immune function. We have also outlined treatment modalities for PIDs, which often entail a multidisciplinary approach involving immunoglobulin replacement, antimicrobial prophylaxis, and, in select cases, hematopoietic stem cell transplantation. Emerging therapies, including gene therapy, hold promise for targeted interventions. In essence, this review encapsulates the complexity of PIDs, emphasizing the critical importance of early diagnosis and tailored therapeutic interventions. As research advances, a clearer understanding of these disorders emerges, fostering optimism for enhanced patient care and management in the future.

Impact of Graft Function on Health Status and Quality of Life in Very Long-Term Survivors Who Received an HSCT for Inborn Errors of Immunity, a Prospective Study of the CEREDIH

The overall survival rate after hematopoietic stem cell transplantation (HSCT) for inborn errors of immunity (IEI) has improved considerably, and its indications have broadened. As a consequence, addressing the issue of long-term health-related quality of life (HRQoL) has become crucial. Our study focuses on the health and HRQoL of post-HSCT survivors. We conducted a multicenter prospective follow-up study enrolling IEI patients who underwent transplantation in childhood before 2009. Self-reported data from the French Childhood Immune Deficiency Long-term Cohort and the 36-item Short Form questionnaires were compiled. One hundred twelve survivors were included with a median duration period from HSCT of 15 years (range 5-37), of whom 55 underwent transplantation for a combined immunodeficiency. We show that in patients evaluated at least 5 years after HSCT, 55% are still affected by a poor or very poor health status. Poor and very poor health status correlated with an abnormal graft function, defined as host or mixed chimerism, abnormal CD3+ count, or diagnosis of chronic graft-versus-host disease (poor health: odds ratio [OR] = 2.6, 95% confidence interval [CI], 1.1-5.9, P = .028; very poor health: OR = 3.6, 95% CI, 1.1-13, P = .049). Poor health was directly linked to a poorer HRQoL. Significant improvements in graft procedures have translated into better survival rates, but we show here that about half of the transplanted patients remain affected by an altered health status with a correlation to both abnormal graft function and impaired HRQoL. Additional studies are needed to confirm the impact of those improvements on long-term health status and HRQoL.

The Treatment of Primary Immune Deficiencies: Lessons Learned and Future Opportunities

Primary immunodeficiency is a group of disorders associated with susceptibility to infectious agents and the development of various comorbidities. Many primary immunodeficiencies are complicated by immune dysregulation, autoinflammation, or autoimmunity which impacts multiple organ systems. Major advances in the treatment of these disorders have occurred over the last half-century, and deeper molecular understanding of many disorders combined with clinically available genetic testing is allowing for use of precision therapy for several primary immunodeficiencies. Patients with antibody deficiencies who rely on immunoglobulin replacement therapy now have many treatment options with products that are much safer and better tolerated compared to the past. Newborn screening for severe combined immunodeficiency, now implemented throughout the USA and in many countries worldwide, has lowered the age at which many patients are diagnosed with these diseases. Early diagnosis of severe combined immunodeficiency allows infants to proceed to definitive therapy such as stem cell transplantation or gene therapy prior to facing potentially life-threatening infections. While stem cell transplantation continues to carry significant risks, knowledge gained over recent decades is allowing for improved survival with less toxicity and less graft versus host disease.

Genomic diagnosis and care co-ordination for monogenic inflammatory bowel disease in children and adults: consensus guideline on behalf of the British Society of Gastroenterology and British Society of Paediatric Gastroenterology, Hepatology and Nutrition

Genomic medicine enables the identification of patients with rare or ultra-rare monogenic forms of inflammatory bowel disease (IBD) and supports clinical decision making. Patients with monogenic IBD frequently experience extremely early onset of treatment-refractory disease, with complex extraintestinal disease typical of immunodeficiency. Since more than 100 monogenic disorders can present with IBD, new genetic disorders and variants are being discovered every year, and as phenotypic expression of the gene defects is variable, adaptive genomic technologies are required. Monogenic IBD has become a key area to establish the concept of precision medicine. Clear guidance and standardised, affordable applications of genomic technologies are needed to implement exome or genome sequencing in clinical practice. This joint British Society of Gastroenterology and British Society of Paediatric Gastroenterology, Hepatology and Nutrition guideline aims to ensure that testing resources are appropriately applied to maximise the benefit to patients on a national scale, minimise health-care disparities in accessing genomic technologies, and optimise resource use. We set out the structural requirements for genomic medicine as part of a multidisciplinary team approach. Initiation of genomic diagnostics should be guided by diagnostic criteria for the individual patient, in particular the age of IBD onset and the patient's history, and potential implications for future therapies. We outline the diagnostic care pathway for paediatric and adult patients. This guideline considers how to handle clinically actionable findings in research studies and the impact of consumer-based genomics for monogenic IBD. This document was developed by multiple stakeholders, including UK paediatric and adult gastroenterology physicians, immunologists, transplant specialists, clinical geneticists, scientists, and research leads of UK genetic programmes, in partnership with patient representatives of several IBD and rare disease charities.

Severe hematopoietic stem cell inflammation compromises chronic granulomatous disease gene therapy

X-linked chronic granulomatous disease (CGD) is associated with defective phagocytosis, life-threatening infections, and inflammatory complications. We performed a clinical trial of lentivirus-based gene therapy in four patients (NCT02757911). Two patients show stable engraftment and clinical benefits, whereas the other two have progressively lost gene-corrected cells. Single-cell transcriptomic analysis reveals a significantly lower frequency of hematopoietic stem cells (HSCs) in CGD patients, especially in the two patients with defective engraftment. These two present a profound change in HSC status, a high interferon score, and elevated myeloid progenitor frequency. We use elastic-net logistic regression to identify a set of 51 interferon genes and transcription factors that predict the failure of HSC engraftment. In one patient, an aberrant HSC state with elevated CEBPβ expression drives HSC exhaustion, as demonstrated by low repopulation in a xenotransplantation model. Targeted treatments to protect HSCs, coupled to targeted gene expression screening, might improve clinical outcomes in CGD.

Case report: Challenges in immune reconstitution following hematopoietic stem cell transplantation for CTLA-4 insufficiency-like primary immune regulatory disorders

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) haploinsufficiency is a T-cell hyperactivation disorder that can manifest with both immunodeficiency and immune dysregulation. Approximately one-third of patients may present mild symptoms and remain stable under supportive care. The remaining patients may develop severe multiorgan autoimmunity requiring lifelong immunosuppressive treatment. Hematopoietic stem cell transplantation (HSCT) is potentially curable for patients with treatment-resistant immune dysregulation. Nevertheless, little experience is reported regarding the management of complications post-HSCT. We present case 1 (CTLA-4 haploinsufficiency) and case 2 (CTLA-4 insufficiency-like phenotype) manifesting with severe autoimmunity including cytopenia and involvement of the central nervous system (CNS), lung, and gut and variable impairment of humoral responses. Both patients underwent HSCT for which the main complications were persistent mixed chimerism, infections, and immune-mediated complications [graft-versus-host disease (GVHD) and nodular lung disease]. Detailed management and outcomes of therapeutic interventions post-HSCT are discussed. Concretely, post-HSCT abatacept and human leukocyte antigen (HLA)-matched sibling donor lymphocyte infusions may be used to increase T-cell donor chimerism with the aim of correcting the immune phenotype of CTLA-4 haploinsufficiency.

Conditioning regimens for inborn errors of immunity: current perspectives and future strategies

Inborn errors of immunity (IEI) are caused by germline genetic mutations, resulting in defects of innate or acquired immunity. Hematopoietic cell transplantation (HCT) is indicated for curative therapy especially in patients with IEI who develop fatal opportunistic infections or severe manifestations of immune dysregulation. The first successful HCT for severe combined immunodeficiency (SCID) was reported in 1968. Since then, the indications for HCT have expanded from SCID to various non-SCID IEI. In general, HCT for IEI differs from that for other hematological malignancies in that the goal is not to eradicate certain immune cells but to achieve immune reconstitution. European Society for Blood and Marrow Transplantation/European Society for Immunodeficiencies guidelines recommend reduced-intensity conditioning to avoid treatment-related toxicity, and the optimal conditioning regimen should be considered for each IEI. We review conditioning regimens for some representative IEI disorders in Japanese and worldwide cohort studies, and future strategies for treating IEI.

Gastrointestinal symptoms as the first sign of chronic granulomatous disease in a neonate: A case report

BACKGROUND

Chronic granulomatous disease (CGD) characterized by recurrent and severe bacterial and fungal infections is most common in childhood.

CASE SUMMARY

We reported a 24-d-old male infant who developed gastrointestinal symptoms as the first sign of CGD.

CONCLUSION

Gastrointestinal symptoms representing the first sign of CGD are very rare, and prompt diagnosis and treatment with broad-spectrum antibiotics were of crucial importance.

Effects of voriconazole on population pharmacokinetics and optimization of the initial dose of tacrolimus in children with chronic granulomatous disease undergoing hematopoietic stem cell transplantation

Background

This study aimed to explore the effects of voriconazole on population pharmacokinetics and optimization of the initial dose of tacrolimus in children with chronic granulomatous disease (CGD) undergoing hematopoietic stem cell transplantation (HSCT).

Methods

Thirty-four children with CGD undergoing HSCT were assessed to establish a population pharmacokinetic model (PPM) using the non-linear mixed effect. Tacrolimus concentrations were simulated by the Monte Carlo method in children weighing <25 kg at different doses.

Results

In the final model, weight and concomitant use of voriconazole were included as covariates. With the same weight, the relative value of tacrolimus clearance was 1:0.388 in children not taking voriconazole: children taking voriconazole. Compared with children not taking voriconazole, the measured tacrolimus concentrations were all higher in children taking voriconazole (P<0.01); however, these were not corrected by dose or body weight for concentration differences. Thus, we simulated the tacrolimus concentrations using different body weights (5–25 kg) and different dose regimens (0.1–0.8 mg/kg/day) for the same body weight and dose. Tacrolimus concentrations in children taking voriconazole were higher than those in children not taking voriconazole (P<0.01). Also, in children with CGD undergoing HSCT who were not taking voriconazole, the initial dose regimen of 0.5 mg/kg/day was recommended for body weights of 5–10 kg, and 0.4 mg/kg/day was recommended for body weights of 10–25 kg. In children with CGD undergoing HSCT who were taking voriconazole, an initial dose regimen of 0.3 mg/kg/day was recommended for body weights of 5–25 kg.

Conclusions

We established, for the first time, a PPM of tacrolimus in children with CGD undergoing HSCT in which voriconazole significantly increased tacrolimus concentrations. In addition, the initial dose of tacrolimus in children with CGD undergoing HSCT was recommended.

Outcome of chronic granulomatous disease - Conventional treatment vs stem cell transplantation

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) can cure chronic granulomatous disease (CGD), but it remains debated whether all conventionally treated CGD patients benefit from HSCT.

METHODS

We retrospectively analyzed 104 conventionally treated CGD patients, of whom 50 patients underwent HSCT.

RESULTS

On conventional treatment, seven patients (13%) died after a median time of 16.2 years (interquartile range [IQR] 7.0-18.0). Survival without severe complications was 10 ± 3% (mean ± SD) at the age of 20 years; 85% of patients developed at least one infection, 76% one non-infectious inflammation. After HSCT, 44 patients (88%) were alive at a median follow-up of 2.3 years (IQR 0.8-4.9): Six patients (12%) died from infections. Survival after HSCT was significantly better for patients transplanted ≤8 years (96 ± 4%) or for patients without active complications at HSCT (100%). Eight patients suffered from graft failure (16%); six (12%) developed acute graft-vs-host disease requiring systemic treatment. Conventionally treated patients developed events that required medical attention at a median frequency of 1.7 (IQR 0.8-3.2) events per year vs 0 (IQR 0.0-0.5) in patients beyond the first year post-HSCT. While most conventionally treated CGD patients failed to thrive, catch-up growth after HSCT in surviving patients reached the individual percentiles at the age of diagnosis of CGD.

CONCLUSION

Chronic granulomatous disease patients undergoing HSCT until 8 years of age show excellent survival, but young children need more intense conditioning to avoid graft rejection. Risks and benefits of HSCT for adolescents and adults must still be weighed carefully.

Hematopoietic Cell Transplantation for Chronic Granulomatous Disease in Japan

Hematopoietic cell transplantation (HCT) is established as a curative treatment for severe chronic granulomatous disease (CGD). However, outcomes of HCT for CGD in Japan had not been precisely reported. We evaluated the outcome of HCT for CGD in Japan by means of a nationwide survey. A total of 91 patients (86 males and 5 females) with CGD who received HCT between 1992 and 2013 was investigated. Their median age at HCT was 11 years (0–39). Sixty-four patients had X-linked CGD caused by CYBB gene mutations, 13 had autosomal recessive CGD (7 CYBA and 6 NCF2), and 14 were genetically undetermined. Seventy patients are still alive at a median follow-up of 38.9 (3.7–230) months. Three-year OS and EFS was 73.7 and 67.6%, respectively. Twenty-one patients died mainly from transplant-related mortality. The cumulative incidence of grade II to IV acute GVHD and extensive chronic GVHD was 27.2 and 17.9%, respectively. Risk factors for EFS after HCT for CGD were age >30 years (P < 0.01), non-CYBB gene mutations (P < 0.01) and CBT (P < 0.01). Regarding the reduced intensity conditioning (RIC) regimen, risk factors for EFS included anti-thymocyte globulin (P = 0.048) and not using low-dose irradiation therapy (P < 0.01), in addition to the preceding risk factors. We report outcomes of HCT for CGD in Japan. Future studies are needed to improve such outcomes, especially for patients harboring non-CYBB gene mutations and suffering from adult CGD. A RIC regimen including low-dose irradiation may be a good option to explore further.

Geographic Variability and Pathogen-Specific Considerations in the Diagnosis and Management of Chronic Granulomatous Disease

Chronic granulomatous disease (CGD) is a rare but serious primary immunodeficiency with varying prevalence and rates of X-linked and autosomal recessive disease worldwide. Functional defects in the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex predispose patients to a relatively narrow spectrum of bacterial and fungal infections that are sometimes fastidious and often difficult to identify. When evaluating and treating patients with CGD, it is important to consider their native country of birth, climate, and living situation, which may predispose them to types of infections that are atypical to your routine practice. In addition to recurrent and often severe infections, patients with CGD and X-linked female carriers are also susceptible to developing many non-infectious complications including tissue granuloma formation and autoimmunity. The DHR-123 oxidation assay is the gold standard for making the diagnosis and it along with genetic testing can help predict the severity and prognosis in patients with CGD. Disease management focuses on prophylaxis with antibacterial, antifungal, and immunomodulatory medications, prompt identification and treatment of acute infections, and prevention of secondary granulomatous complications. While hematopoietic stem-cell transplantation is the only widely available curative treatment for patients with CGD, recent advances in gene therapy may provide a safer, more direct alternative.

Assessment of weight and height of patients with primary immunodeficiency disorders and group of children with recurrent respiratory tract infections

BACKGROUND

Primary immunodeficiences (PIDs) are a group of chronic, serious disorders in which the immune response is insufficient. In consequence, it leads to an increased susceptibility to infections. Up to date, there are about 350 different disorders classified in that group. There are also patients suffering from recurrent respiratory tract infections (RRTI), however that group doesn't present any abnormalities in terms of conducted immunological tests. Many factors, including medical, can have an impact on physical development of a child. Data such as birth weight and length, also weight, height, BMI during admission to the hospital were collected from 195 patients' medical histories from their hospitalization at Clinical Immunology and Paediatrics Ward of J. Gromkowski Hospital in Wrocław. Investigated groups included patients with PIDs, RRTI and a control group of healthy children. Our purpose was to evaluate the physical growth of children with PID and children with RRTI by assessment of their height and weight. All of parameters were evaluated using centile charts, suitable best for the Polish population.

RESULTS

The lowest mean birth weight and height was found among the PIDs patients group. Children with PIDs during hospitalization had statistically relevant lower mean weight than the control group and almost 18% of them had their height situated below 3rd percentile. The statistically relevant differences have been found between them and RRTI group in terms of weight, height and nutritional status. The statistically significant difference was detected between the nutritional status of PID and control group.

CONCLUSIONS

There is a higher percentage of PID patients with physical growth abnormalities in comparison to healthy children. Our findings indicate a need for further investigation of immune system irregularities and their influence on physical growth of children.

Progress in treating chronic granulomatous disease

Chronic granulomatous disease is a primary immunodeficiency due to a defect in one of six subunits that make up the nicotinamide adenine dinucleotide phosphate oxidase complex. The most commonly defective protein, gp91^phox , is inherited in an X-linked fashion; other defects have autosomal recessive inheritance. Bacterial and fungal infections are common presentations, although inflammatory complications are increasingly recognized as a significant cause of morbidity and are challenging to treat. Haematopoietic stem cell transplantation offers cure from the disease with improved quality of life; overall survival in the current era is around 85%, with most achieving long-term cure free of medication. More recently, gene therapy is emerging as an alternative approach. Results using gammaretroviral vectors were disappointing with genotoxicity and loss of efficacy, but preliminary results using lentiviral vectors are extremely encouraging.

Hematopoietic Stem Cell Transplantation Beyond Severe Combined Immunodeficiency: Seeking a Cure for Primary Immunodeficiency

Hematopoietic stem cell transplantation (HSCT) can provide definitive therapy for patients with primary immunodeficiency disease (PIDD). Modern HSCT techniques and supportive care have significantly improved outcomes for patients with PIDD. This review examines current HSCT practice for PIDD other than severe combined immunodeficiency, and explores indications, risks, and long-term outcomes for this group of challenging diseases.

Recent advances in primary immunodeficiency: from molecular diagnosis to treatment

The technological advances in diagnostics and therapy of primary immunodeficiency are progressing at a fast pace. This review examines recent developments in the field of inborn errors of immunity, from their definition to their treatment. We will summarize the challenges posed by the growth of next-generation sequencing in the clinical setting, touch briefly on the expansion of the concept of inborn errors of immunity beyond the classic immune system realm, and finally review current developments in targeted therapies, stem cell transplantation, and gene therapy.

Cellular Therapies in Chronic Granulomatous Disease

Allogeneic hematopoietic stem cell transplantation (HSCT) has become the main curative treatment in patients with chronic granulomatous disease (CGD). CGD is caused by inherited defects of the phagolysomal NADPH-oxidase, leading to a lifelong propensity for invasive infections and granulomatous inflammation. After successful allogeneic HSCT, chronic infections and inflammation resolve and quality-of-life improves. Favorable long-term outcome after HSCT is dependent on the prevention of primary and secondary graft failure (GF), including falling myeloid donor chimerism (DC) below 10 %, and chronic graft-vs.-host-disease (cGVHD). The risk of GF and GvHD increases with the use of HLA-incompatible donors and this may outweigh the benefits of HSCT, mainly in patients with severe co-morbidities and in asymptomatic patients with residual NADPH-oxidase function. Seventeen scientific papers have reported on a total of 386 CGD-patients treated by HSCT with HLA-matched family/sibling (MFD/MSD), 9/10-/10/10-matched-unrelated volunteer (MUD) and cord blood donors. The median OS/EFS-rate of these 17 studies was 91 and 82%, respectively. The median rates of GF, cGVHD and de-novo autoimmune diseases were 14, 10, and 12%, respectively. Results after MFD/MSD and 10/10-MUD-transplants were rather similar, but outcome in adults with significant co-morbidities and after transplants with 9/10 HLA-MUD were less successful, mainly due to increased GF and chronic GVHD. Transplantation protocols using T-cell depleted haploidentical donors with post-transplant cyclophosphamide or TCR-alpha/beta depletion have recently reported promising results. Autologous gene-therapy after lentiviral transduction of HSC achieved OS/EFS-rates of 78/67%, respectively. Careful retrospective and prospective studies are mandatory to ascertain the most effective cellular therapies in patients with CGD.

Health-Related Quality of Life and Emotional Difficulties in Chronic Granulomatous Disease: Data on Adult and Pediatric Patients from Italian Network for Primary Immunodeficiency (IPINet)

Chronic granulomatous disease (CGD) is a primary immunodeficiency characterized by life-threatening infections, inflammation, and autoimmunity with an impact on health-related quality of life (HRQoL). Few data are available for children, whereas no study has been conducted in adults. Here, we investigated HRQoL and emotional functioning of 19 children and 28 adults enrolled in Italian registry for CGD. PEDsQL and SDQ were used for children and their caregivers, and adults completed the SF-12 questionnaire. Mean scores were compared with norms and with patients affected by chronic diseases. Comparisons were made for CGD patients who underwent or not hematopoietic stem cell transplantation (HSCT). When compared with norms, CGD children exhibited higher difficulties in social/school areas, peer relationship, and conduct/emotional problems (< 5 years of age), as scored by proxies. Differently, CGD adults reported higher difficulties both in mental and physical area than norms. Only for children, clinical status had a damaging effect on psychosocial and school dimensions, whereas age had a negative impact on social areas. No significant difference was observed between patients treated or not with HSCT. When compared with patients affected by chronic diseases, CGD children and adults both displayed fewer physical disabilities. Differently, in mental scale adults scored lower than those with rheumatology diseases and had similar impairment in comparison with patients with diabetes mellitus and cancer. This study emphasized the impact of CGD on HRQoL since infancy and its decline in adulthood, with emotional difficulties occurring early. HRQoL impairment should be considered in clinical picture of CGD and pro-actively assessed and managed by clinicians.

The extended understanding of chronic granulomatous disease

PURPOSE OF REVIEW

We briefly address the advances in genetics, pathophysiology, and phenotypes of chronic granulomatous disease (CGD). This is one of the most studied primary immunodeficiencies, which comprise mutations in genes encoding the different subunits of the NADPH oxidase system. Those mutations lead to defective reactive oxygen species production, and consequently a failure to eliminate pathogens.

RECENT FINDINGS

Patients with CGD are susceptible to fungal, bacterial, and parasitic infections. Other symptoms, as systemic adverse effects to BCG vaccine and hyperinflammation, are also important clinical conditions in this disease. This wide-ranging clinical spectrum of CGD comes from heterogeneity of mutations, X-linked-CGD or autosomal recessive inheritance, and diverse environmental pressure factors. Early accurate diagnosis and prompt treatment are necessary to diminish the consequences of the disease. The most used diagnostic tests are dihydrorhodamine, cytochrome c reduction, and luminol-enhanced chemiluminescence assay.

SUMMARY

The determination of mutations is essential for diagnosis confirmation and genetic counseling. CGD treatment usually includes prophylactic antibiotics and antifungals. Prophylactic recombinant human interferon-γ, immunosuppressors or immune modulators may be, respectively, indicated for preventing infections or inflammatory manifestations. Hematopoietic stem cell transplantation and gene therapy are currently the available options for curative treatment of CGD.

High Levels of IL-18 and IFN-γ in Chronically Inflamed Tissue in Chronic Granulomatous Disease

Background: Chronic granulomatous disease (CGD) is caused by a malfunctioning nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex in phagocytes, leading to impaired bacterial and fungal killing and hyperinflammation.

Objective: To characterize macrophage subsets and cytokine/chemokine signaling loops involved in CGD tissue hyperinflammation.

Methods: Cytokine/chemokine production and surface marker expression were analyzed in inflamed tissue of four CGD patients and compared to cytokine/chemokine released by CGD macrophages upon priming to different macrophage subpopulations. Furthermore, the re-priming capacity of CGD pro-inflammatory M1 to M2a anti-inflammatory macrophages was evaluated.

Results: In human CGD inflammatory tissue, IL-18 and IFN-γ were detected in significant quantity. Immunofluorescence analysis identified macrophages as one source of IL-18 in inflamed tissue. In vitro, CGD macrophages could be primed and re-primed into all inflammatory/anti-inflammatory macrophage subpopulations. IL-18 was also released by M1 CGD and control macrophages.

Conclusion: CGD pro-inflammatory M1 macrophages remain M1 primed in vivo. As CGD M1 macrophages can be re-primed to anti-inflammatory M2a phenotype in vitro, macrophages are kept in M1 state in vivo by a persistent pro-inflammatory environment. Our results suggest a paracrine signaling loop between M1 macrophage derived IL-18 and non-macrophage derived IFN-γ maintaining macrophage pro-inflammatory activity in CGD tissue.

[A clinical study of haploid hematopoietic stem cells combined with third-party umbilical cord blood transplantation in the treatment of chronic granulomatous disease]

OBJECTIVE

To investigate the clinical efficacy of haploid hematopoietic stem cells (haplo-HSC) combined with third-party umbilical cord blood (tpCB) transplantation in the treatment of X-linked chronic granulomatous disease (X-CGD).

METHODS

The clinical data of 26 boys with X-CGD were retrospectively analyzed who were admitted to the Sixth Medical Center of PLA General Hospital between April 2014 and March 2018. All the patients were treated with haplo-HSC combined with tpCB transplantation. The median age of the patients was 3.5 years. The donor was the father in 25 cases and an aunt in 1 case. Transplantation was 5/6 HLA-matched in 9 cases, 4/6 in 12 cases, and 3/6 in 5 cases. The patients received busulfan, cyclophosphamide, fludarabine, or anti-thymocyte globulin for myeloablative preconditioning. Cyclosporine A and mycophenolate mofetil were used for prevention of acute graft-versus-host disease (aGVHD). Then the patients were treated with haploid bone marrow hematopoietic stem cells combined with tpCB transplantation on day 1 and haploid peripheral hematopoietic stem cells on day 2. The counts of median donor total nucleated cells, CD34⁺ cells, and CD3⁺ cells were 14.6×10⁸/kg, 5.86×10⁶/kg, and 2.13×10⁸/kg respectively.

RESULTS

The median time to neutrophil and platelet engraftment was 12 and 23 days after transplantation respectively. Full donor hematopoietic chimerism was observed on day 30. Twenty-five cases were from haplo-HSC and 1 was from cord blood. No primary implant failure and implant dysfunction occurred, and secondary implant failure occurred in one case. The NADPH oxidase activity returned to normal one month after transplantation. The incidence of grade I-II aGVHD and grade III-IV aGVHD was 35% and 15% respectively. Chronic GVHD (cGVHD) of the skin occurred in one case, and no progression was observed after steroid administration. During the follow-up period of 6-51 months, 25 patients survived, of whom 24 were disease-free (23 patients without cGVHD and 1 with cGVHD of the skin) and NADPH oxidase activity returned to normal; one patient developed secondary implant failure but survived; one patient died of viral interstitial pneumonia 16 months after transplantation. The 5-year event-free survival rate and overall survival rate were 81%±12% and 89%±10% respectively.

CONCLUSIONS

Haplo-HSC combined with tpCB transplantation is one of the effective methods for the treatment of X-CGD in children.

Health-Related Quality of Life and Emotional Health in X-Linked Carriers of Chronic Granulomatous Disease in the United Kingdom

X-linked chronic granulomatous disease (XL-CGD), a rare primary immunodeficiency due to a defect in the gp91^phox NADPH oxidase subunit, results in recurrent, severe infection, inflammation, and autoimmunity. Patients have an absent, or significantly reduced, neutrophil oxidative burst. Due to lyonization, XL-CGD carriers have a dual population of functional and non-functional phagocytes and experience a range of symptoms including increased risk of autoimmunity, fatigue, and infection. Patients with CGD have poorer quality of life (QoL) than normal controls. We evaluated QoL and psychological health in UK XL-CGD carriers. Recruited participants completed the Medical Outcomes Study Short Form 36 version 2 (SF-36 V2), providing an overall score for mental and physical health. Psychological health was assessed using the Hospital Anxiety and Depression Scale (HADS) questionnaire. Seventy-five XL-CGD carriers were recruited from 62 families, median age 43 years (range 3-77). Fifty-six were mothers, 6 grandmothers, and 13 siblings. Sixty-two completed the SF36v2 and had reduced QoL scores compared with adult CGD patients and a UK age-matched female control cohort, indicating a reduced QoL. Sixty-one completed a HADS questionnaire. Over 40% experienced moderate or greater levels of anxiety with only one third being classified as normal. Higher anxiety scores significantly correlated with higher depression scores, lower self-esteem, presence of joint or bowel symptoms, and higher levels of fatigue (p < 0.05). This is the first study to evaluate QoL of XL-CGD carriers, and demonstrates high rates of anxiety and significantly reduced QoL scores. XL-CGD carriers should be considered as potential patients and pro-actively assessed and managed.

Genetic and Clinical Profiles of Disseminated Bacillus Calmette-Guérin Disease and Chronic Granulomatous Disease in China

Background: Disseminated Bacillus Calmette-Guérin disease (D-BCG) in children with chronic granulomatous disease (CGD) can be fatal, while its clinical characteristics remain unclear because both diseases are extremely rare. The patients with CGD receive BCG vaccination, because BCG vaccination is usually performed within 24 h after delivery in China.

Methods: We prospectively followed-up Chinese patients with CGD who developed D-BCG to characterize their clinical and genetic characteristics. The diagnoses were based on the patients' clinical, genetic, and microbiological characteristics.

Results: Between September 2009 and September 2016, we identified 23 patients with CGD who developed D-BCG. Their overall 10-year survival rate was 34%. We created a simple dissemination score to evaluate the number of infected organ systems and the survival probabilities after 8 years were 62 and 17% among patients with simple dissemination scores of ≤3 and >3, respectively (p = 0.0424). Survival was not significantly associated with the CGD stimulation index or interferon-γ treatment. Eight patients underwent umbilical cord blood transplantation and 5 of them were successfully treated. The genetic analyses found mutations in CYBB (19 patients), CYBA (1 patient), NCF1 (1 patient), and NCF2 (1 patient). We identified 6 novel highly likely pathogenic mutations, including 4 mutations in CYBB and 2 mutations in NCF1.

Conclusions: D-BCG is a deadly complication of CGD. The extent of BCG spreading is strongly associated with clinical outcomes, and hematopoietic stem cell transplantation may be a therapeutic option for this condition.

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiency Diseases: Current Status and Future Perspectives

Primary immunodeficiencies (PID) are disorders that for the most part result from mutations in genes involved in immune host defense and immunoregulation. These conditions are characterized by various combinations of recurrent infections, autoimmunity, lymphoproliferation, inflammatory manifestations, atopy, and malignancy. Most PID are due to genetic defects that are intrinsic to hematopoietic cells. Therefore, replacement of mutant cells by healthy donor hematopoietic stem cells (HSC) represents a rational therapeutic approach. Full or partial ablation of the recipient's marrow with chemotherapy is often used to allow stable engraftment of donor-derived HSCs, and serotherapy may be added to the conditioning regimen to reduce the risks of graft rejection and graft versus host disease (GVHD). Initially, hematopoietic stem cell transplantation (HSCT) was attempted in patients with severe combined immunodeficiency (SCID) as the only available curative treatment. It was a challenging procedure, associated with elevated rates of morbidity and mortality. Overtime, outcome of HSCT for PID has significantly improved due to availability of high-resolution HLA typing, increased use of alternative donors and new stem cell sources, development of less toxic, reduced-intensity conditioning (RIC) regimens, and cellular engineering techniques for graft manipulation. Early identification of infants affected by SCID, prior to infectious complication, through newborn screening (NBS) programs and prompt genetic diagnosis with Next Generation Sequencing (NGS) techniques, have also ameliorated the outcome of HSCT. In addition, HSCT has been applied to treat a broader range of PID, including disorders of immune dysregulation. Yet, the broad spectrum of clinical and immunological phenotypes associated with PID makes it difficult to define a universal transplant regimen. As such, integration of knowledge between immunologists and transplant specialists is necessary for the development of innovative transplant protocols and to monitor their results during follow-up. Despite the improved outcome observed after HSCT, patients with severe forms of PID still face significant challenges of short and long-term transplant-related complications. To address this issue, novel HSCT strategies are being implemented aiming to improve both survival and long-term quality of life. This article will discuss the current status and latest developments in HSCT for PID, and present data regarding approach and outcome of HSCT in recently described PID, including disorders associated with immune dysregulation.

Hematopoietic Stem Cell Transplantation for Primary Immunodeficiencies

The field of primary immunodeficiencies has pioneered many of the advances in haematopoietic stem cell transplantation and cellular therapies over the last 50 years. The first patients to demonstrate sustained benefit and prolonged cure from the primary genetic defect following allogeneic haematopoietic stem cell transplantation were patients with primary immunodeficiencies. Although primary immunodeficiency patients began the modern era of haematopoietic stem cell transplantation, the history is nevertheless short-in answer to the question "what is the long term outcome of patients transplanted for primary immunodeficiencies?" we often have to say that we do not know. We believe that most patients who undergo haematopoietic stem cell transplantation for primary immunodeficiencies should live a normal lifespan with a fully corrected immune system. We are now beginning to understanding long term outcomes, the relationship to the underlying genetic defect, age, and pre-morbid condition of the patient at time of transplantation, stem cell source and donor, and effect of pre-transplant cytoreductive chemotherapy conditioning. The long term consequences of post-transplant complications such as graft vs. host disease, veno-occlusive disease, or immune dysregulation are also being recognized. Additionally, some genetic defects have a systemic distribution, and we are learning the natural history of these defects once the immunodeficiency has been removed.

Chronic Granulomatous Disease

Chronic granulomatous disease is a clinical condition that stems from inactivating mutations in NOX2 and its auxiliary proteins. Together, these proteins form the phagocyte NADPH oxidase enzyme that generates superoxide. Superoxide (O₂^ċ-) and its reduced product hydrogen peroxide (H₂O₂) give rise to several additional reactive oxygen species (ROS), which together are necessary for adequate killing of pathogens. Thus, CGD patients, with a phagocyte NADPH oxidase that is not properly functioning, suffer from recurrent, life-threatening infections with certain bacteria, fungi, and yeasts. Here, I give a short survey of the genetic mutations that underlie CGD, the effect of these mutations on the activity of the leukocyte NADPH oxidase, the clinical symptoms of CGD patients, and the treatment options for these patients.

Long Term Outcome and Immune Function After Hematopoietic Stem Cell Transplantation for Primary Immunodeficiency

Transplantation techniques for patients with primary immunodeficiencies have improved so that survival from the procedure in many cases is >80%. However, long term complications may arise due to the use or not of conditioning agents. This may result in variable immune reconstitution, the long term effects of chemotherapy, particularly on fertility, and complications relating to the genetic disorder, unresolved by transplantation. For patients with severe combined immunodeficiency (SCID), long term T- and B-lymphocyte immune reconstitution is best achieved after pre-transplant chemotherapy. For patients who receive an unconditioned infusion of donor stem cells, the quality of immune reconstitution depends on the SCID genotype. Long term effects include chemotherapy-induced impaired fertility, and sequelae specific to the genotype. For patients with other primary immunodeficiencies, conditioning is required-sequelae related to direct effects of chemotherapy may be observed. Additional long term effects may be observed due to partial donor chimerism resulting in incomplete eradication of disease, and other geno-specific effects.

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiencies Beyond Severe Combined Immunodeficiency

Hematopoietic stem cell transplantation (HSCT) has been the standard of care for infants with severe combined immunodeficiency (SCID) for several decades due to the dismal prognosis early in life without immune reconstitution. In recent years, as HSCT conditioning regimens and supportive care have greatly improved, HSCT is gaining in acceptance for more non-SCID primary immunodeficiencies (PIDs) and outside the early childhood period. In addition, potential donor options for non-SCID PIDs are expanding with increasing success for haploidentical donor transplants. In this brief report of a presentation at the PIDS-St. Jude 2018 conference, PIDs for which transplants are increasingly performed outside of early childhood will be discussed.

Haploidentical stem cell transplantation in a boy with chronic granulomatous disease

Chronic granulomatous disease is a primary immunodeficiency caused by mutations in any one of the five components of the NADPH oxidase in phagocytic leucocytes. This causes impaired microbial killing, which leads to severe life-threatening bacterial and fungal infections. Currently, allogenic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for chronic granulomatous disease, although gene therapy may provide a new therapeutic option for the treatment of patients with CGD. Haploidentical HSCT provides a potentially curative treatment option for patients who lack a suitably HLA-matched donor, but only a few cases have been reported in the literature. Herein, we report a boy with X-linked chronic granulomatous disease treated successfully by haploidentical HSCT with post-transplant cyclophosphamide using a treosulfan-based conditioning regimen.

Chronic Granulomatous Disease First Diagnosed in Adulthood Presenting With Spinal Cord Infection

Chronic granulomatous disease (CGD) is a rare genetic immunodeficiency, which is characterized by recurrent severe bacterial and fungal infections caused by a defect in phagocytic cells due to loss of superoxide production. The disease usually manifests within the first years of life. Early diagnosis allows therapeutic intervention to improve the limited life expectancy. Nevertheless, only half of the patients exceed the age of 25. Here, we present the case of a 41-year old female patient who presented with an extensive spinal cord infection and atypical pneumonia mimicking tuberculosis. The medical history with recurrent granulomatous infections and microbiological findings with multiple unusual opportunistic pathogens was the key to the diagnosis of CGD, which is exceptionally rare first diagnosed in patients in the fifth decade of life. The late diagnosis in this case was likely due to the lack of knowledge of the disease by the treating teams before but not because the patient did not have typical CGD infections along her life. The extensive progressive developing granulomas in our patient with fatal outcome raise the question of early immunosuppressive therapy in addition to anti-infectious treatment. We recommend appropriate CGD diagnostics in adult patients with unclear granulomatous diseases of the nervous system.

Future of Care for Patients With Chronic Granulomatous Disease: Gene Therapy and Targeted Molecular Medicine

Chronic granulomatous disease is a rare and potentially fatal disorder of neutrophil function. Beyond current medical management and hematopoietic stem cell transplantation, new methods of gene therapy that use lentiviral vectors or gene editing might extend curative therapies to patients who lack a suitable transplantation donor while eliminating the risk of graft-versus-host disease. Furthermore, new therapies focused on altering the biology of phagolysosomes might offer novel targeted treatments for inflammatory complications in patients with chronic granulomatous disease.

Allogeneic Hematopoietic Cell Transplantation for Chronic Granulomatous Disease: Controversies and State of the Art

Chronic granulomatous disease (CGD) is a congenital disorder characterized by recurrent life-threatening bacterial and fungal infections and development of severe inflammation secondary to a congenital defect in 1 of the 5 phagocyte oxidase (phox) subunits of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Hematopoietic cell transplant (HCT) is a curative treatment for patients with CGD that provides donor neutrophils with functional NADPH and superoxide anion production. Many characteristics of CGD, including preexisting infection and inflammation and the potential for cure with mixed-donor chimerism, influence the transplant approach and patient outcome. Because of the dangers of short-term death, graft-versus-host disease, and late effects from chemotherapy, HCT historically has been reserved for patients with high-risk disease and a matched donor. However, as advances in CGD and HCT treatments have evolved, recommendations on transplant eligibility also must be amended, but the development of modern guidelines has proven difficult. In this review, we provide an overview of HCT in patients with CGD, including the debate over HCT indications in them, the unique aspects of CGD that can complicate HCT, and a summary of transplant outcomes.

Clinical considerations in the hematopoietic stem cell transplant management of primary immunodeficiencies

INTRODUCTION

Primary immunodeficiencies (PID) are genetic immune disorders causing increased predisposition to infections and autoimmunity. The only curative procedure is hematopoietic stem cell transplantation (HSCT), results from which have improved dramatically since 2000. Complications remain a serious issue, especially in HLA non-identical transplantation. In PID patients, persistent infection and autoimmunity with end-organ damage cause particular problems with approach to transplantation. This article examines these, emphasising approach to management and consequences. Areas covered: It is challenging to know which patients should be offered HSCT. As new diseases are discovered, data are required to determine natural history, and HSCT outcomes. Treatment of adults can be challenging, although HSCT outcomes are encouraging. New methods of T-lymphocyte depletion show results comparable to those of matched sibling donor transplants. New cellular therapies to treat viral infections show promising results, and immunomodulatory methods are successful in treating acute graft-versus-host disease. Expert commentary: New T-lymphocyte depletion methods are a paradigm shift in approach to HSCT for PID. In combination with new cellular approaches to treating viral infection, immunomodulatory approaches to acute graft-versus-host disease and better understanding of endothelial activation syndromes, survival approaches 90%. Widespread introduction of newborn screening for severe combined immunodeficiencies will improve survival further.

Burden of Poor Health Conditions and Quality of Life in 656 Children with Primary Immunodeficiency

OBJECTIVE

To gain insight into how primary immunodeficiencies (PIDs) affect children's health status and quality of life.

STUDY DESIGN

The French Reference Center for PIDs conducted a prospective multicenter cohort that enrolled participants who met all criteria: patients included in the French Reference Center for PIDs registry, children younger than18 years, and living in France. Participants were asked to complete both a health questionnaire and a health-related quality of life (HR-QoL) questionnaire. A severity score was assigned to each health condition: grade 1 (mild) to grade 4 (life-threatening). HR-QoL in children was compared with age- and sex-matched French norms.

RESULTS

Among 1047 eligible children, 656 were included in the study, and 117 had undergone hematopoietic stem cell transplantation; 40% experienced at least one grade 4 condition, and 83% experienced at least one grade 3 or 4 condition. Compared with the French norms, children with PID scored significantly lower for most HR-QoL domains. Low HR-QoL scores were associated strongly with burden of poor conditions.

CONCLUSIONS

Our results quantify the magnitude of conditions in children with PID and demonstrate that the deleterious health effects borne by patients already are evident in childhood. These results emphasize the need to closely monitor this vulnerable population and establish multidisciplinary healthcare teams from childhood.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02868333 and EudraCT 2012-A0033-35.

Hematopoietic cell transplantation in primary immunodeficiency - conventional and emerging indications

INTRODUCTION

Hematopoietic stem cell transplantation (HSCT) is an established curative treatment for many primary immunodeficiencies. Advances in donor selection, graft manipulation, conditioning and treatment of complications, mean that survival for many conditions is now around 90%. Next generation sequencing is identifying new immunodeficiencies, many of which are treatable with HSCT. Challenges remain however with short and long-term sequalae. This article reviews latest developments in HSCT for conventional primary immunodeficiencies and presents data on outcome for emerging diseases, Areas covered: This article reviews recently published literature detailing advances, particularly in conditioning regimens and new methods of T-lymphocyte depletion, as well as new information regarding approach and out come of transplanting patients with conventional primary immunodeficiencies. The article reviews data regarding transplant outcomes for newly described primary immunodeficiencies, particularly those associated with gain-of-function mutations. Expert commentary: New methods of graft manipulation have had significant impact on HSCT outcomes, with the range of PIDs treated using T-lymphocyte depletion significantly expanded. Outcomes for newly described diseases with variable phenotypes and clinical features, transplanted when the diagnosis was unknown are beginning to be described, and will improve as patients are identified earlier, and targeted therapies such as JAK inhibitors are used as a bridge to transplantation.