Initial presenting manifestations in 16,486 patients with inborn errors of immunity include infections and noninfectious manifestations

The paradox of autoimmune thrombocytopenia in common variable immunodeficiency

Common variable immunodeficiency (CVID) is the most common primary immunodeficiency requiring medical intervention and is heterogeneous in clinical presentation and outcome. Beyond susceptibility to infections, many patients with CVID develop chronic lung disease, enteropathy, granulomatous disease, lymphoproliferation and autoimmunity. Immune thrombocytopenia (ITP) is the most common autoimmune condition associated with CVID, impacting 4%-19% of CVID patients, while CVID is found in 1%-2% of ITP patients. Given that CVID is defined by decreased antibody production, the underlying pathophysiology of CVID-associated ITP remains elusive.

Chronic Kidney Disease in Common Variable Immunodeficiency: a Multicenter Study

PURPOSE

There are few reports of renal involvement in Common Variable Immunodeficiencies (CVID) and, when present, is due to infections, inflammation, or treatments. The aim of this study was evaluating the prevalence of chronic kidney disease (CKD) and to identify CVID-related clinical, laboratory and therapeutic features inducing it.

METHODS

A multicenter observational retrospective study on 367 adult CVID patients from five Italian Referral Centers for Primary Immunodeficiency.

RESULTS

CKD was identified in 23 (6.27%) patients that were older (p < 0.001), had arterial hypertension (p < 0.001), diabetes (p = 0.002), dyslipidemia (p = 0.002), presented different ultrasound abnormalities (p < 0.001) and received predominantly intravenous immunoglobulins (IVIG) (p = 0.016). Regarding CVID infectious and non-infectious manifestations, CKD patients presented a higher frequency of COPD (p = 0.008). In the CKD group, the median absolute count of total lymphocytes (p = 0.015), the percentage of total B (p = 0.028) and transitional B cells (p = 0.008) were lower. By binomial logistic regression analysis adjusted for age, CKD patients tend to develop autoimmune cytopenia, had lower B cells percentage, increased Neutrophil-to-lymphocyte ratio and received more frequently trimethoprim-sulfamethoxazole antibiotic prophylaxis. By multivariate analysis, only autoimmune cytopenia was independently associated with CKD.

CONCLUSION

The prevalence of CKD in CVID is due to aging, age-related comorbidities, disease-related immune dysregulation and inflammation. Our results suggest evaluating renal function in all CVID patients, and mostly in those with a higher "inflammatory" burden.

Rhinosinusitis: Evidence and experience - 2024

It has been 10-years since the publication of Rhinosinusitis: evidence and experience, and since then a lot has changed in our understanding of the disease. Advances in pathophysiology, endotyping and new treatments such as biologics brought a new era in the management of our patients. This new guideline, developed jointly by ABR and ABORL-CCF, with the help of ASBAI presents an updated, evidence-based approach to the different forms of rhinosinusitis that aims to improve the diagnosis and treatment of this complex disease. The document covers a wide range of topics, including clear definitions of the different stages of acute sinusitis. It also introduces a new term called Prolonged Acute Viral Rhinosinusitis. Reviews phenotypes and endotypes of chronic rhinosinusitis, recommending methods for clinical and laboratory investigation, clinical and surgical treatment. We also discuss in detail fungal sinusitis and pediatric sinusitis. The objective of this updated Consensus is to clarify some already established and recent concepts, highlighting the importance of an accurate diagnosis to promote treatment approaches that reflect the best practices based on solid evidence. Therefore, we seek not only to improve the results of patients care, but also to guide thealth professionals through a clinical panorama that is in constant transformation.

International multidisciplinary consensus on the definition and clinical approach for monogenic inflammatory immune dysregulation disorders

OBJECTIVE

To achieve consensus on the definition and clinical approach of Monogenic Inflammatory Immune Dysregulation Disorders (MIIDDs), a collective term for rare conditions marked by inflammation, immune dysregulation, and infection susceptibility. These consensus guidelines specifically apply to pathogenic (or likely pathogenic) gene mutations affecting both innate and adaptive immunity, excluding variants of unknown significance (VUS).

METHODS

A multi-step, evidence-based, multidisciplinary consensus process was employed, consisting of: (1) a systematic literature review across four electronic databases (Cochrane Library, Web of Science, Scopus, and MEDLINE via PubMed), updated through December 31, 2024; (2) a pre-Delphi electronic survey completed by 95 international adult and pediatric immunologists and rheumatologists; and (3) a modified online Delphi process with an international multidisciplinary expert panel, where statements were iteratively analyzed and refined until achieving consensus (≥ 80% agreement among panelists).

RESULTS

Fifteen experts from 12 countries participated in two rounds of the Delphi process, resulting in the development of eight overarching principles and 10 consensus statements. These were categorized into five domains: (1) definitions and conceptual framework, (2) diagnostic and monitoring considerations, (3) treatment and therapeutic strategies, (4) multidisciplinary and collaborative care, and (5) patient education and support.

CONCLUSION

This consensus defines MIIDDs and provides a structured clinical framework to streamline research efforts and improve patient outcomes.

Prevalence of Ophthalmological Manifestations in Patients with Inborn Errors of Immunity: A Systematic Review and Meta-Analysis

BACKGROUND

Although some reports indicate ocular involvement in Inborn Errors of Immunity (IEI) patients, the characteristics of this association remain unclear. Increased awareness can facilitate early diagnosis and prevention of visual complications.

OBJECTIVE

To determine the prevalence and characterize ophthalmological manifestations in patients with IEI.

METHODS

A systematic literature search was performed across Embase, PubMed, and Lilacs. Observational studies with at least 10 IEI patients exhibiting ophthalmological manifestations were reviewed. A meta-analysis using a random effects model, weighted proportion, and 95% confidence intervals were reported as appropriate.

RESULTS

Sixty-two articles out of the 6,884 studies were included. The pooled prevalence of ocular manifestations in IEI patients was 54% (95%CI = 39-69), with a mean age of 11.1 ± 7.8 years and male predominance. Regarding the type of IEI with ocular involvement, the most frequently affected group was the Combined immunodeficiencies with associated or syndromic features (82%, 95%CI = 66-91), followed by the diseases of immune dysregulation (73%, 95%CI = 27-95), auto-inflammatory disorders (48%, 95%CI = 10-88), and congenital defects of phagocytes (39%, 95%CI = 11-76). Europe had the highest prevalence of patients with ocular manifestations (68%, 95%CI = 32-90). The most common ocular manifestations observed in IEI patients were those affecting ocular mobility, followed by those that involved the anterior segment, posterior segment, eyelids, and adnexal structures.

CONCLUSIONS

These results highlight a significant burden of ocular involvement in IEI patients, mainly during childhood and associated with amblyogenic factors. Therefore, ophthalmologists, pediatricians, and immunologists must be involved in early detection to prevent ocular complications and overall well-being.

Diagnostic disparities in inborn errors of immunity: From clinical suspicion to diagnosis

Background

Emerging evidence suggests that inborn errors of immunity (IEI) are underdiagnosed among underserved populations. However, there remains a lack of national studies evaluating diagnostic disparities in IEI.

Objective

We examined disparities in the timely IEI diagnosis and related health outcomes.

Methods

A retrospective analysis was performed of a US national claims database (years 2007 to 2021). Participants included patients diagnosed with an "unspecified immune deficiency" (uID) and presented with IEI-related symptoms, who later received an IEI diagnosis (n = 1429). We quantified the diagnostic interval from clinical suspicion (uID) to IEI diagnosis and examined its association with sociodemographic factors and related health outcomes.

Results

The median (interquartile range) diagnostic interval was 369 (126-808) days. Diagnostic interval was 14% longer among patients residing in predominantly non-White neighborhoods, compared with those in predominantly White neighborhoods (P = .04), despite having more severe IEI-related symptoms at uID diagnosis and significantly more health care encounters for pneumonia (incidence rate ratio, 2.24; 95% confidence interval, 1.40-3.70) and sepsis (incidence rate ratio, 2.15; 95% confidence interval, 1.21-3.99) in the year after uID diagnosis. Residence in neighborhoods with greater deprivation was also associated with more severe IEI-related symptoms and greater health care utilization in the year after uID diagnosis. Older age was associated with longer diagnostic interval (P < .001). Longer diagnostic interval was associated with a longer interval to receiving IgR therapy (hazard ratio, 0.64; 95% confidence interval, 0.49-0.83).

Conclusion

We observed significant racial and socioeconomic disparities in the timeliness of IEI diagnosis and IEI-related outcomes. Further studies are needed to address the underlying factors contributing to diagnostic inequity.

Letermovir-inclusive combination therapy for a refractory and resistant infection by cytomegalovirus with UL54 mutation following a hematopoietic stem cell transplant for MHC class II deficiency

Cytomegalovirus (CMV) infection remains one of the most common and challenging post-transplant infections. Children with inborn errors of immunity (IEI) and T-cell dysfunction are at high risk for CMV infection, which can be complicated by refractory and/or resistant cases. This case describes a Nepalese girl with MHC class II deficiency, who presented at 3 months of age with CMV and Pneumocystis jirovecii pneumonia. Hematopoietic stem cell transplantation (HSCT) was planned as a curative treatment for IEI. Initial antiviral therapy with ganciclovir, followed by foscarnet, achieved undetectable CMV viral loads. However, the viral load rebounded during foscarnet therapy. HSCT was performed at 7 months of age using peripheral blood stem cells from her CMV-seropositive father, despite the recipient's high CMV viral load. Empiric combination therapy with cidofovir (an unapproved drug in Japan), foscarnet, leflunomide, and artesunate was initiated. CMV genetic testing revealed UL54 mutations conferring high-level resistance to foscarnet and moderate-level resistance to ganciclovir. The regimen was adjusted to letermovir, ganciclovir, leflunomide, and artesunate, which successfully suppressed the viral load following engraftment. At three months post-HSCT, combination therapy was discontinued after sustained undetectable CMV viral loads. Although CMV infection was controlled, the patient died from idiopathic pulmonary hemorrhage at five months post-HSCT. This case highlights the potential efficacy of a letermovir-inclusive therapy regimen in managing drug-resistant CMV with UL54 mutations in a pediatric HSCT recipient.

Genomic profiling at a single center cracks the code in inborn errors of immunity

Inborn errors of immunity (IEI) entail a diverse group of disorders resulting from hereditary or de novo mutations in single genes, leading to immune dysregulation. This study explores the clinical utility of next-generation sequencing (NGS) techniques in diagnosing monogenic immune defects. Eight patients attending the immunodeficiency clinic and with unclassified antibody deficiency were included in the analysis. Clinical records, immune characteristics, and family histories were reviewed, and a target gene panel (TGP) sequencing was performed to identify pathogenic variants. TGPs identified seven variants in TNFRSF13B (TACI), CARMIL2, STAT1, STAT3, and ORAI1 genes. These findings provided definitive diagnoses and proper prognostic assessment. Patients exhibited a wide range of clinical manifestations, including recurrent infections, autoimmune cytopenias, and organ-specific complications. The genetic diversity observed highlights the importance of genetic testing in diagnosing IEIs and tailoring treatments. This study underscores the role of TGPs in diagnosing IEIs, revealing significant genetic heterogeneity and phenotypic variability. They offer a precise tool for identifying underlying genetic defects, facilitating personalized medicine approaches, and eventually improving patient outcomes. The findings emphasize the need for comprehensive genetic testing to uncover novel pathogenic variants, enhancing our understanding of immune system dysfunction. NGS is a critical tool for the management of IEI, enabling precise diagnosis and personalized treatment strategies. Despite resource limitations, the progressive affordability is likely to expand its clinical utility, ultimately improving patient care and advancing the field of immunology. In the meantime, accurate phenotypic assessment is essential for resource optimization and case prioritization.

Consensus of the Italian Primary Immunodeficiency Network on the use and interpretation of genetic testing for diagnosing inborn errors of immunity

BACKGROUND

Inborn errors of immunity (IEIs) comprise more than 500 different rare congenital disorders of the immune system and are characterized by susceptibility to infection and immune dysregulation. The significant overlap of the clinical features among the different forms may lead to diagnostic delay. High-throughput sequencing techniques may allow a timely genetic definition. Guidelines for the use and the interpretation of genetic testing produced by the American College of Medical Genetics and Genomics (ACMG) and the European Society of Human Genetics (ESHG) do not cover specifics for their application to IEIs.

OBJECTIVE

The aim of this consensus study was to define the best approach to genetic testing for IEIs.

METHODS

A panel of experts in the context of the Italian Primary Immunodeficiency Network (IPINet) composed a list of statements that were evaluated by the Delphi method.

RESULTS

The experts recommend that genetic testing for IEIs should be offered to selected patients with warning signs for IEIs and highlight the crucial role of thorough phenotyping and functional tests for the conclusive diagnosis of IEI. Comprehensive educational programs targeted to health care professionals and the public should be developed to increase IEIs awareness and reduce diagnostic delay. Ethical issues should be pondered over the diagnostic advantages of genetic tests requested for diagnostic purposes.

CONCLUSION

Adherence to guidelines on the use and interpretation of genetic tests for diagnosing IEIs should help limit the inappropriate use of these techniques, thereby reducing the risk of misdiagnosis and patient apprehension regarding inconclusive genetic results.

Keeping up with recent developments in immunodeficiency

Inborn errors of immunity (IEIs) are a rapidly expanding group of monogenetic disorders affecting the immune system. Advancements in genetic testing and functional validation studies have accelerated the pace of IEI gene discovery and mechanism of disease, particularly in the past 5 years. To keep up with this rapid expansion, the International Union of Immunological Societies Expert Committee has periodically, since 1999, released updated IEI classifications with corresponding genotypic and phenotypic catalogues with its most recent update in 2022. Now, there are more than 485 monogenetic disorders of the immune system described among 10 main groups of classification. This article reviews recent clinical developments in IEI, including a closer look at some of the more recently described IEI disorders. In particular, we highlight a few disorders with the following clinical phenotypes of IEI: severe atopy, immunodeficiency with immune dysregulation, immune dysregulation with lymphoproliferation, autoinflammation, and innate phenotype. To aid the clinician, we also provide a diagnostic approach to use when there is suspicion of IEI and a discussion of management and treatment.

Monogenic Common Variable Immunodeficiency (Mo-CVID) Score for Optimizing the Genetic Diagnosis in Pediatric CVID Cohort

Common variable immunodeficiency (CVID) represents an "umbrella" diagnosis due to its clinical and immunological heterogeneity. The primary objective of this study was to describe a cohort of CVID pediatric subjects from clinical, immunological, and genetic viewpoints. Secondary, we propose a model for prioritizing genetic investigations in these patients. Thirty-four patients with CVID followed at Meyer Children's Hospital, IRCSS, were enrolled. Whole exome sequencing was performed according to the latest International Union of Immunological Societies 2022 update. Genetic variants were identified in 16 patients (47%), including known variants in SLC39A7, PRKCD, STAT3, NFKB1, PIK3R1, PLCG2, RFXANK, PRKDC, TNFRSF13B, and novel variants in SPI1, NFKB1, NFKB2. Comparing the Gene+ and Gene- cohorts, we demonstrated that a monogenic cause is more likely to be found in cases of early disease onset, positive family history, autoimmunity, lymphoproliferation, and specific immunological alterations. Using these criteria, we developed a pediatric monogenic CVID (Mo-CVID) score to hypothesize when a CVID pediatric patient is more likely to carry a genetic mutation. A scoring system such as the Mo-CVID score could help physicians prioritize genetic testing. Genetic analysis in CVID patients can help stratify patients into different disease entities to predict complications and prognosis, ensure appropriate genetic counseling, and personalize treatment.

If and When to Consider Prophylactic Immunoglobulin Replacement Therapy in Secondary Hypogammaglobulinemia

Secondary hypogammaglobulinemia (SHG), or decreased IgG levels due to reduced production or increased loss caused by medications or underlying conditions, can be associated with increased infection risk. Although immunoglobulin replacement therapy (IgRT) is generally accepted as a strategy to help prevent recurrent bacterial infections in SHG, controversy exists as to whether it should be initiated to prevent the first occurrence of infection. This question has been raised particularly in the setting of anti-CD20 therapy, solid organ transplant, and B-cell malignancies and their treatments once IgG levels fall below 300 to 400 mg/dL. This article reviews the evidence for and against initiating IgRT in these settings, as well as associated considerations for evaluation and monitoring. Although it is relatively clear that infection risk increases with decreasing IgG levels, the exact contribution of SHG to overall infection risk and the protective benefit of IgRT in the absence of infections remain unclear. In the absence of clear consensus, shared decision-making is often needed to determine if and when to initiate IgRT.

Clinical manifestations, disease penetrance, and treatment in individuals with SOCS1 insufficiency: a registry-based and population-based study

BACKGROUND

Suppressor of cytokine signalling 1 (SOCS1) insufficiency is an inborn error of immunity affecting the negative regulation of cytokine and growth factor signalling. We aimed to enhance the understanding of clinical manifestations, disease trajectories, disease penetrance, and the effect of Janus kinase (JAK) inhibition in individuals with SOCS1 insufficiency.

METHODS

This study used data from two independent cohorts: the European Society for Immunodeficiencies (ESID) registry and the UK Biobank. Participants from the ESID registry were from nine European countries (Austria, Belgium, France, Germany, Ireland, Italy, Portugal, Sweden, and Ukraine), China, Taiwan, and the USA. Participants from the ESID registry were eligible if they had heterozygous, functionally validated SOCS1 variants; participants from the UK Biobank were included if they had any SOCS1 variant detected in the ESID registry cohort or any other SOCS1 variant that was classed as high-impact. Clinical manifestations of the underlying SOCS1 insufficiency were documented and summarised into nine subgroups, with ICD-10 diagnosis codes collected for participants from the UK Biobank. Participants from the ESID registry were tested for relevant autoantibodies in their local laboratory. Responses to JAK inhibitor treatment in participants from the ESID registry were assessed by the treating physician using a visual analogue scale. Descriptive statistics were used for analysis. People with lived experience were not involved in the study design.

FINDINGS

We included 119 participants with SOCS1 insufficiency: 67 from the ESID registry, enrolled between Feb 15, 2021, and Dec 31, 2023, and 52 from the UK Biobank. Of the 67 participants from the ESID registry, 39 (58%) were female, 28 (42%) were male, and the median age was 28 years (IQR 15-44, range 2-85). 27 different monoallelic SOCS1 variants were identified in these participants. 62 (93%) of the 67 participants in the ESID registry cohort were symptomatic and five (7%) were asymptomatic family members; of the 62 participants with symptoms, allergy (33 [50%]), inflammatory gastrointestinal (22 [36%]) and skin (18 [29%]) manifestations, autoimmune cytopenia (24 [39%]), and lymphoproliferation (23 [37%]) were most frequent. Rheumatological manifestations (23 [37%]) included systemic lupus erythematosus, Sjögren's disease, and rheumatoid arthritis, with typical autoantibody profiles. 42 (68%) of the 62 symptomatic participants had at least three different manifestations. In the UK Biobank we found 52 participants carrying high-impact SOCS1 variants; 29 (56%) were female, 23 (44%) were male, and the median age was 72 years (65-78, 57-86). Only 30 (58%) of these participants had developed manifestations that were potentially related to SOCS1 insufficiency. Allergy and rheumatological manifestations were more common in participants from the UK Biobank than the ESID registry. Female predominance (21 [70%] of 30 participants were female and nine [30%] were male) was also found among symptomatic participants from the UK Biobank. Treatment with JAK inhibitors showed promising results in 12 (92%) of 13 participants in the ESID registry.

INTERPRETATION

SOCS1 insufficiency differs from other genetic autoimmune lymphoproliferative disorders by the presence of frequent atopic and rheumatological manifestations. Penetrance is incomplete and is higher in females than in males. JAK inhibition is a promising targeted therapy for patients with SOCS1 insufficiency.

FUNDING

German Research Foundation (DFG).

Use of Immunoglobulin Replacement Therapy in Clinical Practice: A Review

Immunoglobulins (Igs) are produced by B lymphocytes and play a key role in humoral immunity. Igs are classified into five isotypes (IgG, IgA, IgM, IgE, and IgD). Their primary function is to recognize and bind to foreign antigens. When Igs bind to antigens, they facilitate phagocytosis and promote clearance mediated by other immune cells. It is an essential component in protecting the host from outside pathogens. Hypogammaglobulinemia predisposes an individual to severe and recurrent infections. Therefore, replacement therapy is recommended to maintain optimal Ig level. In addition, Igs can modulate immune responses by to neutralizing proteins such as endotoxins or receptor-binding antibodies. They can be used to manage excessive immune reactions and autoimmune-related diseases. In this review, we aimed to summarize the clinical indications for Ig therapy for practicing oncologists.

[Retrospective analysis in children with vaccination granuloma]

BACKGROUND

Vaccine granulomas are a common (0.3-1%) adverse event (AE) of (accidentally) subcutaneously administered vaccines and specific immunotherapies containing aluminum conjugates. The clinical symptoms with persistent itching subcutaneous nodules, predominantly affect infants and young children on the lateral thigh.

AIM

To sensitize dermatologists to recognize this common and harmless vaccination AE, in order to prevent invasive diagnostics and confusion among parents and physicians.

MATERIALS AND METHODS

Retrospective analysis of 13 children consulting pediatric dermatology between 2019 and 2023. Identification of diagnostic criteria and guidelines for action, based on the literature.

RESULTS AND CONCLUSION

In all, 13 children (9 boys, 4 girls) with subcutaneous indolent but itching nodules at the vaccination sites (11 on the thighs, 2 on the upper arms) with a latency of weeks to months were retrospectively evaluated. The children were vaccinated according to German STIKO ("Ständige Impfkommission") recommendations. Only inactivated vaccines contain aluminum. The documented occurrence of the first vaccination granulomas was between the 12th and 36th month of life. Regarding the STIKO vaccination calendar, the third immunization with the hexavalent inactivated vaccine coincides with the first administration of the live measles, mumps and rubella (MMR) vaccine (varicella (V)). This may incorrectly lead to the assumption that the live vaccine was the cause of granuloma development. Aluminum conjugation appears to be a central trigger of the granulomas; further susceptibility factors are largely unknown. Diagnosis of sensitization to aluminum through epicutaneous testing has no practical impact and is, therefore, not routinely recommended. After weeks to years, granulomas spontaneously regress.

Expanding the diagnostic toolbox for complex genetic immune disorders

Laboratory-based immunology evaluation is essential to the diagnostic workup of patients with complex immune disorders, and is as essential, if not more so, depending on the context, as genetic testing, because it enables identification of aberrant pathways amenable to therapeutic intervention and clarifies variants of uncertain significance. There have been considerable advances in techniques and instrumentation in the clinical laboratory in the past 2 decades, although there are still "miles to go." One of the goals of the clinical laboratory is to ensure advanced diagnostic testing is widely accessible to physicians and thus patients, through reference laboratories, particularly in the context of academic medical centers. This ensures a greater likelihood of translating research discoveries into the diagnostic laboratory, on the basis of patient care needs rather than a sole emphasis on commercial utility. However, these advances are under threat from burdensome regulatory oversight that can compromise, at best, and curtail, at worst, the ability to rapidly diagnose rare immune disorders and ensure delivery of precision medicine. This review discusses the clinical utility of diagnostic immunology tools, beyond cellular immunophenotyping of lymphocyte subsets, which can be used in conjunction with clinical and other laboratory data for diagnosis as well as monitoring of therapeutic response in patients with genetic immunologic diseases.

Comparative efficacy of leniolisib (CDZ173) versus standard of care on rates of respiratory tract infection and serum immunoglobulin M (IgM) levels among individuals with activated phosphoinositide 3-kinase delta (PI3Kδ) syndrome (APDS): an externally controlled study

Leniolisib, an oral, targeted phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, was well-tolerated and efficacious versus placebo in treating individuals with activated PI3Kδ syndrome (APDS), an ultra-rare inborn error of immunity (IEI), in a 12-week randomised controlled trial. However, longer-term comparative data versus standard of care are lacking. This externally controlled study compared the long-term effects of leniolisib on annual rate of respiratory tract infections and change in serum immunoglobulin M (IgM) levels versus current standard of care, using data from the leniolisib single-arm open-label extension study 2201E1 (NCT02859727) and the European Society for Immunodeficiencies (ESID) registry. The endpoints were chosen following feasibility assessment considering comparability and availability of data from both sources. Baseline characteristics between groups were balanced through inverse probability of treatment weighting. The leniolisib-treated group included 37 participants, with 62 and 49 participants in the control group for the respiratory tract infections and serum IgM analyses, respectively. Significant reductions in the annual rate of respiratory tract infections (rate ratio: 0.34; 95% confidence interval [CI]: 0.19, 0.59) and serum IgM levels (treatment effect: -1.09 g/L; 95% CI: -1.78, -0.39, P = 0.002) were observed in leniolisib-treated individuals versus standard of care. The results were consistent across all sensitivity analyses, regardless of censoring, baseline infection rate definition, missing data handling, or covariate selection. These novel data provide an extended comparison of leniolisib treatment versus standard of care, highlighting the potential for leniolisib to deliver long-term benefits by restoring immune system function and reducing infection rate, potentially reducing complications and treatment burden.

Nutritional status in pediatric patients with predominant antibody deficiency

Introduction

Predominant antibody deficiency is the most frequent group of innate immunity errors, but information about patients’ nutritional status is scarce.

Objectives

To characterize the nutritional status of Colombian patients with predominant antibody deficiencies.

Material and methods

Material and methods. We analyzed medical charts of patients with predominant antibody deficiency in a pediatric hospital in Bogotá.

Results

We analyzed 55 medical charts. The most frequent diagnoses were specific deficiencies of polysaccharide antibodies and immunoglobulin A, common variable immunodeficiency, and agammaglobulinemia. More than 70% of the patients had sinopulmonary infections, with pneumonia being the most frequent, followed by otitis and sinusitis. In children under five years, 45% had adequate weight for their height, 18% had a risk of malnutrition, and 18% had moderate acute malnutrition. Four-point-five percent had obesity, 4.5% showed overweight, and 9% had a risk of being overweight. Of those older than five years, 54% had an adequate body mass index, 22.5% showed overweight, 9.6% were at risk of thinness, and 9.6% were thin. We found that the risk of short stature and short stature per se were more frequent than the expected height in these patients. The percentages of patients with short stature were higher than those reported nationally.

Conclusions

Due to the epidemic of childhood obesity, it will be more frequent to find overweight or obesity in children above five years. Therefore, finding short stature could be a more sensitive alarm sign for predominant antibody deficiency.

Second part

.

Unmasking inborn errors of immunity: identifying the red flags of immune dysregulation

Inborn errors of immunity (IEI) are rare diseases that affect the immune system. According to the latest International Union of Immunological Societies (IUIS) classification, 485 different IEI have been identified. Even if increased susceptibility to infections is the best-known symptom, IEI are no longer defined by the higher likelihood of infections alone. Immune dysregulation with autoimmune disease and hyperinflammation, lymphoproliferation, and malignancy are common manifestations and could be the only symptoms of IEI that must be recognized. An exclusive focus on infection-centered warning signs would miss around 25% of patients with IEI who initially present with other manifestations. Timely and appropriate diagnosis and treatment are essential to enhance the quality of life (QoL) and, in some cases, survival, as patients are susceptible to life-threatening infections or autoimmunity. In addition, the advantage of early diagnosis in IEI with immune dysregulation (i.e. CTLA4 deficiency, LRBA deficiency, NF-kB1/NF-kB2 deficiency, activated phosphoinositide 3-kinase delta syndrome -APDS-) is the initiation of targeted therapies with precise re-balancing of the dysregulated immune pathways (i.e., biologicals, selective inhibitors) or definitive therapy (i.e., HSCT).

Practical considerations in diagnosing inborn errors of immunity according to the Middle East and North Africa guidelines

PURPOSE OF REVIEW

The rate of inborn errors of immunity (IEI) in the Middle East and North Africa (MENA) region is generally higher than in other parts of the world. IEI patients in MENA exhibit more severe disease phenotypes. One of the most important reasons for this is delayed diagnosis. In this review, we examine issues pertinent to primary, secondary, and tertiary physicians in diagnosing IEI in children and discuss the key points for pediatricians according to the MENA guideline.

RECENT FINDINGS

Protocols and stepwise approaches designed by a panel of clinical immunologists included in the MENA-IEI registry network can help physicians facilitate the diagnosis of patients with IEI by providing recommendations. These recommendations for diagnostic approaches improve the care of patients within the MENA region and can also be applied to IEI patients in other parts of the world other regions.

SUMMARY

Physicians in the MENA region should be aware of IEI, obtain a detailed family history, request tests that can be ordered in primary care when IEI is suspected, and refer patients to clinical immunologists without delay. Primary and secondary care physicians should be aware that patients with IEI may present with noninfectious manifestations and increased infection frequency, severity, and atypical infections.

Association of paediatric autoimmune cytopenia and inflammatory bowel disease suggests a common genetic origin

The association of autoimmune cytopenia (AIC) and inflammatory bowel disease (IBD) has been reported in small series, but the incidence of and risk factors for IBD in children with AIC are not known. One thousand six hundred nine children with chronic immune thrombocytopenic purpura, autoimmune haemolytic anaemia or Evans syndrome from the prospective OBS'CEREVANCE cohort are included in this study. Overall, 15 children were diagnosed with IBD, including 14 who developed IBD after AIC diagnosis (median delay: 21 months). The only risk factor for IBD development is age at AIC over 10 years. Out of 10 children genetically tested, germline variants associated with autoimmune disorders were identified in three (CTLA4: two, DOCK11: one). In children and adolescents monitored for AIC or past history of AIC, especially children over 10 years, gastro-intestinal (GI) symptoms (recurrent abdominal pains, GI bleeding, chronic diarrhoea, weight loss) should suggest IBD and deserve specific work-up and genetic studies. Identification of a causal germline variant will allow targeted therapy.

Delineating the Clinical and Immunologic Characteristics: A Comparative Study of Inborn Errors of Immunity in Adult versus Pediatric Diagnosed

INTRODUCTION

Inborn errors of immunity (IEIs) are rare genetic disorders primarily identified in children due to their significant effects on immune system functionality. However, an increasing number of IEI cases are being diagnosed in adults, attributed to delayed presentation or advancements in diagnostic capabilities. This study explores the clinical and immunologic distinctions between IEIs diagnosed in adulthood versus childhood, shedding light on their differential presentations, the impact of diagnostic delays, and treatment outcomes.

METHODS

This study focused on 122 adult patients with IEI above 17 years old, diagnosed in adulthood or childhood. We collected comprehensive data on demographics, clinical presentations, genetic mutations, and therapeutic interventions.

RESULTS

The study revealed that 72.9% of participants were diagnosed in adulthood, facing a median diagnostic delay of 96 months. Diagnostic delays were longer in adults (132 months vs. 24 months) than in children. The most common clinical manifestations at onset were recurrent infections (46.7%) and autoimmunity (18%). Predominantly antibody deficiency was the most frequently diagnosed immunodeficiency (54.9%), followed by immunodysregulation at a rate of 26.2%. A higher incidence of immune thrombocytopenia or other complications, such as hepatomegaly and enteropathy, was observed in adult-diagnosed patients with IEI. Malignancies were more prevalent in patients with adult-onset IEI compared to those with childhood-onset (18.1% vs. 5.2%). Overall, 15 different malignancies were recorded in 13 patients (10.6%), including lymphomas and cancers of the stomach, thymus, skin, breast, and colon.

CONCLUSIONS

The findings highlight a considerable diagnostic delay in recognizing IEI, especially in adults, and illustrate distinct differences in disease manifestation and progression between adult-onset and delayed-diagnosis groups.

Inborn Errors of Immunity in Early Childhood: Essential Insights for the Neonatologist

BACKGROUND

Inborn errors of immunity (IEI), formerly referred to as primary immunodeficiencies, manifest with a wide range of symptoms such as increased susceptibility to infections, immune dysregulation, and autoinflammation. Although most cases manifest in childhood, onset during the neonatal period is rare but potentially critical.

SUMMARY

In this review, we discuss the diverse clinical presentations of IEI and the specific challenges they pose to neonatologists. Rather than detailing every molecular defect, we focus on common clinical scenarios in neonates and young infants, providing practical diagnostic strategies to ensure timely and effective therapeutic interventions.

KEY MESSAGES

Clinical presentations of IEI in neonates may include delayed separation of the umbilical cord, skin rashes such as eczema and erythroderma, and recurrent episodes of inflammation. We also highlight immunological emergencies that require urgent medical attention, such as hyperinflammatory activity mimicking acute neonatal liver failure, sometimes seen in hemophagocytic lymphohistiocytosis. We also discuss appropriate medical action in the case of a positive newborn screening for severe T-cell defects. Early medical intervention in such circumstances may significantly improve outcomes.

IPINeT Ped-unPAD Study: Goals, Design, and Preliminary Results

Background: An unclassified primary antibody deficiency (unPAD) is a widely heterogeneous clinical entity, recently identified within the spectrum of Inborn Errors of Immunity (IEIs). Since unPAD has been traditionally considered as a mild condition, it has incorrectly received little attention, resulting in the paucity of extensive and comparable studies describing its natural history. To address the gaps in characterizing, understanding, and managing pediatric unPAD patients, the Italian Primary Immunodeficiency Network (IPINet) Ped-unPAD study has recently been launched. Methods: Seventeen IPINeT Centers have expressed interest to participate, and data collection is still on-going. Hereby, we anticipate preliminary key issues emerging from the first 110 enrolled patients, attending three IPINet Centers. Results: A proportion of unPAD patients have experienced a severe infectious phenotype, which required hospitalization in a quarter of patients and antibiotic prophylaxis or Immunoglobulin Replacement Therapy in approximately 10% of patients. In this partial cohort, a mean follow-up (FU) of 5 years confirmed unPAD diagnosis in fifty percent of cases, with the remaining being reclassified as the Transient Hypogammaglobulinemia of Infancy (25%) and other IEIs (25%), such as a Common Variable Immunodeficiency, Selective IgA deficiency, Selective IgM deficiency, and IgG3 subclass deficiency. Conclusions: Despite a phenotype overlap at diagnosis, clinicians should be aware that unPAD is a mutable condition that deserves comprehensive evaluation and long-term monitoring to dissect the final diagnosis for optimal treatment.

Primary immunodeficiency diseases of adults: a review of pulmonary complication imaging findings

Our objective in this review is to familiarize radiologists with the spectrum of initial and progressive CT manifestations of pulmonary complications observed in adult patients with primary immunodeficiency diseases, including primary antibody deficiency (PAD), hyper-IgE syndrome (HIES), and chronic granulomatous disease (CGD). In patients with PAD, recurrent pulmonary infections may lead to airway remodeling with bronchial wall-thickening, bronchiectasis, mucus-plugging, mosaic perfusion, and expiratory air-trapping. Interstitial lung disease associates pulmonary lymphoid hyperplasia, granulomatous inflammation, and organizing pneumonia and is called granulomatous-lymphocytic interstitial lung disease (GLILD). The CT features of GLILD are solid and semi-solid pulmonary nodules and areas of air space consolidation, reticular opacities, and lymphadenopathy. These features may overlap those of mucosa-associated lymphoid tissue (MALT) lymphoma, justifying biopsies. In patients with HIES, particularly the autosomal dominant type (Job syndrome), recurrent pyogenic infections lead to permanent lung damage. Secondary infections with aspergillus species develop in pre-existing pneumatocele and bronchiectasis areas, leading to chronic airway infection. The complete spectrum of CT pulmonary aspergillosis may be seen including aspergillomas, chronic cavitary pulmonary aspergillosis, allergic bronchopulmonary aspergillosis (ABPA)-like pattern, mixed pattern, and invasive. Patients with CGD present with recurrent bacterial and fungal infections leading to parenchymal scarring, traction bronchiectasis, cicatricial emphysema, airway remodeling, and mosaicism. Invasive aspergillosis, the major cause of mortality, manifests as single or multiple nodules, areas of airspace consolidation that may be complicated by abscess, empyema, or contiguous extension to the pleura or chest wall. CLINICAL RELEVANCE STATEMENT: Awareness of the imaging findings spectrum of pulmonary complications that can occur in adult patients with primary immunodeficiency diseases is important to minimize diagnostic delay and improve patient outcomes. KEY POINTS: • Unexplained bronchiectasis, associated or not with CT findings of obliterative bronchiolitis, should evoke a potential diagnosis of primary autoantibody deficiency. • The CT evidence of various patterns of aspergillosis developed in severe bronchiectasis or pneumatocele in a young adult characterizes the pulmonary complications of hyper-IgE syndrome. • In patients with chronic granulomatous disease, invasive aspergillosis is relatively frequent, often asymptomatic, and sometimes mimicking or associated with non-infectious inflammatory pulmonary lesions.

Inborn Errors of Immunity in Jordan: First Report from a Tertiary Referral Center

PURPOSE

Inborn errors of immunity (IEI) are a heterogeneous group of diseases with variable clinical phenotypes. This study was conducted to describe the epidemiology, clinical presentations, treatment, and outcome of IEI in Jordanian children.

METHODS

A retrospective data analysis was conducted for children under 15 years diagnosed with IEI from the pediatric Allergy, Immunology, and Rheumatology Division-based registry at Queen Rania Children's Hospital, Amman, Jordan, between 2010 and 2022.

RESULTS

A total of 467 patients, 263 (56.3%) males and 204 (43.7%) females, were diagnosed with IEI. The mean age at symptom onset was 18 months (1 week to 144 months), a positive family history of IEI was reported in 43.5%, and the consanguinity rate was 47.9%. The most common IEI category was immunodeficiencies affecting cellular and humoral immunity at 33.2%, followed by predominantly antibody deficiencies at 16.9%. The overall median diagnostic delay (range) was 6 (0-135) months; patients with a positive family history of IEI had a statistically significant shorter diagnostic delay. Pulmonary and gastrointestinal clinical features were the most common at 55.2% and 45.6%, respectively. The overall mortality was 33.2%; the highest rate was reported in severe combined immunodeficiency at 56.2%.

CONCLUSIONS

The high minimal estimated IEI prevalence at 16.2/100,000 Jordanian children compared to the regional and worldwide data, with the diversities in clinical presentation and distribution of IEI categories in our cohort point to unique features of IEI in Jordanian children, call for national registry establishment, regional and international collaborative networks.

A large deletion in a non-coding regulatory region leads to NFKB1 haploinsufficiency in two adult siblings

Mutations in NFkB pathway genes can cause inborn errors of immunity (IEI), with NFKB1 haploinsufficiency being a significant etiology for common variable immunodeficiency (CVID). Indeed, mutations in NFKB1 are found in 4 to 5% of in European and United States CVID cohorts, respectively; CVID representing almost ¼ of IEI patients in European countries registries. This case study presents a 49-year-old patient with respiratory infections, chronic diarrhea, immune thrombocytopenia, hypogammaglobulinemia, and secondary lymphoma. Comprehensive genetic analysis, including high-throughput sequencing of 300 IEI-related genes and copy number variation analysis, identified a critical 2.6-kb deletion spanning the first untranslated exon and its upstream region. The region's importance was confirmed through genetic markers indicative of enhancers and promoters. The deletion was also found in the patient's brother, who displayed similar but milder symptoms. Functional analysis supported haploinsufficiency with reduced mRNA and protein expression in both patients. This case underscores the significance of copy number variation (CNV) analysis and targeting noncoding exons within custom gene panels, emphasizing the broader genomic approaches needed in medical genetics.

The autoimmune rheumatological presentation of Common Variable Immunodeficiency Disorders with an overview of genetic testing

Primary immunodeficiency Disorders (PIDS) are rare, mostly monogenetic conditions which can present to a number of specialties. Although infections predominate in most PIDs, some individuals can manifest autoimmune or inflammatory sequelae as their initial clinical presentation. Identifying patients with PIDs can be challenging, as some can present later in life. This is often seen in patients with Common Variable Immunodeficiency Disorders (CVID), where symptoms can begin in the sixth or even seventh decades of life. Some patients with PIDs including CVID can initially present to rheumatologists with autoimmune musculoskeletal manifestations. It is imperative for these patients to be identified promptly as immunosuppression could lead to life-threatening opportunistic infections in these immunocompromised individuals. These risks could be mitigated by prior treatment with subcutaneous or intravenous (SCIG/IVIG) immunoglobulin replacement or prophylactic antibiotics. Importantly, many of these disorders have an underlying genetic defect. Individualized treatments may be available for the specific mutation, which may obviate or mitigate the need for hazardous broad-spectrum immunosuppression. Identification of the genetic defect has profound implications not only for the patient but also for affected family members, who may be at risk of symptomatic disease following an environmental trigger such as a viral infection. Finally, there may be clinical clues to the underlying PID, such as recurrent infections, the early presentation of severe or multiple autoimmune disorders, as well as a relevant family history. Early referral to a clinical immunologist will facilitate appropriate diagnostic evaluation and institution of treatment such as SCIG/IVIG immunoglobulin replacement. This review comprises three sections; an overview of PIDs, focusing on CVID, secondly genetic testing of PIDs and finally the clinical presentation of these disorders to rheumatologists.

Clinical updates in inborn errors of immunity: a focus on the noninfectious clinical manifestations

PURPOSE OF REVIEW

In the last 5 years, several new inborn errors of immunity (IEI) have been described, especially in the areas of immune dysregulation and autoinflammation. As a result, the clinical presentation of IEIs has broadened. We review the heterogeneous presentation of IEIs and detail several of the recently described IEIs with a focus on the noninfectious manifestations commonly seen.

RECENT FINDINGS

IEIs may present with early onset and/or multiple autoimmune manifestations, increased risk for malignancy, lymphoproliferation, severe atopy, autoinflammation and/or hyperinflammation. Because of this, patients can present to a wide array of providers ranging from primary care to various pediatric subspecialists. The International Union of Immunological Societies (IUIS) expert committee has created a phenotypic classification of IEIs in order to help clinicians narrow their evaluation based on the laboratory and clinical findings.

SUMMARY

Both primary care pediatricians and pediatric subspecialists need to be aware of the common clinical features associated with IEI and recognize when to refer to allergy-immunology for further evaluation. Early diagnosis can lead to earlier treatment initiation and improve clinical outcomes for our patients.

Infections in Disorders of Immune Regulation

Primary immune regulatory disorders (PIRDs) constitute a spectrum of inborn errors of immunity (IEIs) that are primarily characterized by autoimmunity, lymphoproliferation, atopy, and malignancy. In PIRDs, infections are infrequent compared to other IEIs. While susceptibility to infection primarily stems from antibody deficiency, it is sometimes associated with additional innate immune and T or NK cell defects. The use of immunotherapy and chemotherapy further complicates the immune landscape, increasing the risk of diverse infections. Recurrent sinopulmonary infections, particularly bacterial infections such as those associated with staphylococcal and streptococcal organisms, are the most reported infectious manifestations. Predisposition to viral infections, especially Epstein-Barr virus (EBV)-inducing lymphoproliferation and malignancy, is also seen. Notably, mycobacterial and invasive fungal infections are rarely documented in these disorders. Knowledge about the spectrum of infections in these disorders would prevent diagnostic delays and prevent organ damage. This review delves into the infection profile specific to autoimmune lymphoproliferative syndrome (ALPS), Tregopathies, and syndromes with autoimmunity within the broader context of PIRD. Despite the critical importance of understanding the infectious aspects of these disorders, there remains a scarcity of comprehensive reports on this subject.

Inborn errors of immunity: A field without frontiers

The study of primary immunodeficiencies or inborn errors of immunity continues to drive our knowledge of the function of the human immune system. From the outset, the study of inborn errors has focused on unraveling genetic etiologies and molecular mechanisms. Aided by the continuous growth in genetic diagnostics, the field has moved from the study of an infection dominated phenotype to embrace and unravel diverse manifestations of autoinflammation, autoimmunity, malignancy, and severe allergy in all medical disciplines. It has now moved from the study of ultrarare presentations to producing meaningful impact in conditions as diverse as inflammatory bowel disease, neurological conditions, and hematology. Beyond offering immunogenetic diagnosis, the study of underlying inborn errors of immunity in these conditions points to targeted treatment which can be lifesaving.

Multilayer concept of autoimmune mechanisms and manifestations in inborn errors of immunity: Relevance for precision therapy

Autoimmunity in inborn errors of immunity (IEIs) has a multifactorial pathogenesis and develops subsequent to a genetic predisposition in conjunction with gene regulation, environmental modifiers, and infectious triggers. On the basis of incremental data availability owing to upfront application of omics technologies, a more granular and dynamic view of mechanisms and manifestations is warranted. Here, we present a comprehensive novel concept of autoimmunity in IEIs that considers multiple layers of interdependent elements and connects 101 causative genes or deletions according to the quality of the allelic variants with 47 molecular pathways and 22 immune effector mechanisms. Furthermore, we list 50 resulting manifestations together with the corresponding Human Phenotype Ontology terms and review the types and frequencies of the most relevant clinical presentations. When all of its elements are taken together, this concept (1) extends the historical anatomic view of central versus peripheral tolerance toward multiple interdependent mechanisms of immune tolerance, (2) delineates the mechanisms underlying the protean clinical manifestations, and thereby, (3) points toward the most suitable precision therapy for autoimmunity in IEIs. The multilayer concept of autoimmune mechanisms and manifestations in IEIs will facilitate research design and provide clinical guidance on the use of precision medicine irrespective of the data depth available in each health care scenario.

Enrichment of Immune Dysregulation Disorders in Adult Patients with Human Inborn Errors of Immunity

Human inborn errors of immunity (IEI) comprise a group of diseases resulting from molecular variants that compromise innate and adaptive immunity. Clinical features of IEI patients are dominated by susceptibility to a spectrum of infectious diseases, as well as autoimmune, autoinflammatory, allergic, and malignant phenotypes that usually appear in childhood, which is when the diagnosis is typically made. However, some IEI patients are identified in adulthood due to symptomatic delay of the disease or other reasons that prevent the request for a molecular study. The application of next-generation sequencing (NGS) as a diagnostic technique has given rise to an ever-increasing identification of IEI-monogenic causes, thus improving the diagnostic yield and facilitating the possibility of personalized treatment. This work was a retrospective study of 173 adults with IEI suspicion that were sequenced between 2005 and 2023. Sanger, targeted gene-panel, and whole exome sequencing were used for molecular diagnosis. Disease-causing variants were identified in 44 of 173 (25.43%) patients. The clinical phenotype of these 44 patients was mostly related to infection susceptibility (63.64%). An enrichment of immune dysregulation diseases was found when cohorts with molecular diagnosis were compared to those without. Immune dysregulation disorders, group 4 from the International Union of Immunological Societies Expert Committee (IUIS), were the most prevalent among these adult patients. Immune dysregulation as a new item in the Jeffrey Model Foundation warning signs for adults significantly increases the sensitivity for the identification of patients with an IEI-producing molecular defect.

Novel Genetic and Phenotypic Expansion in Ameliorated PUF60-Related Disorders

Heterozygous variants in the Poly(U) Binding Splicing Factor 60kDa gene (PUF60) have been associated with Verheij syndrome, which has the key features of coloboma, short stature, skeletal abnormalities, developmental delay, palatal abnormalities, and congenital heart and kidney defects. Here, we report five novel patients from unrelated families with PUF60-related disorders exhibiting novel genetic and clinical findings with three truncating variants, one splice-site variant with likely reduced protein expression, and one missense variant. Protein modeling of the patient's missense variant in the PUF60 AlphaFold structure revealed a loss of polar bonds to the surrounding residues. Neurodevelopmental disorders were present in all patients, with variability in speech, motor, cognitive, social-emotional and behavioral features. Novel phenotypic expansions included movement disorders as well as immunological findings with recurrent respiratory, urinary and ear infections, atopic diseases, and skin abnormalities. We discuss the role of PUF60 in immunity with and without infection based on recent organismic and cellular studies. As our five patients showed less-severe phenotypes than classical Verheij syndrome, particularly with the absence of key features such as coloboma or palatal abnormalities, we propose a reclassification as PUF60-related neurodevelopmental disorders with multi-system involvement. These findings will aid in the genetic counseling of patients and families.

Diagnostic evaluation of paediatric autoimmune lymphoproliferative immunodeficiencies (ALPID): a prospective cohort study

BACKGROUND

Lymphoproliferation and autoimmune cytopenias characterise autoimmune lymphoproliferative syndrome. Other conditions sharing these manifestations have been termed autoimmune lymphoproliferative syndrome-like diseases, although they are frequently more severe. The aim of this study was to define the genetic, clinical, and immunological features of these disorders to improve their diagnostic classification.

METHODS

In this prospective cohort study, patients were referred to the Center for Chronic Immunodeficiency in Freiburg, Germany, between Jan 1, 2008 and March 5, 2022. We enrolled patients younger than 18 years with lymphoproliferation and autoimmune cytopenia, lymphoproliferation and at least one additional sign of an inborn error of immunity (SoIEI), bilineage autoimmune cytopenia, or autoimmune cytopenia and at least one additional SoIEI. Autoimmune lymphoproliferative syndrome biomarkers were determined in all patients. Sanger sequencing followed by in-depth genetic studies were recommended for patients with biomarkers indicative of autoimmune lymphoproliferative syndrome, while IEI panels, exome sequencing, or genome sequencing were recommended for patients without such biomarkers. Genetic analyses were done as decided by the treating physician. The study was registered on the German Clinical Trials Register, DRKS00011383, and is ongoing.

FINDINGS

We recruited 431 children referred for autoimmune lymphoproliferative syndrome evaluation, of whom 236 (55%) were included on the basis of lymphoproliferation and autoimmune cytopenia, 148 (34%) on the basis of lymphoproliferation and another SoIEI, 33 (8%) on the basis of autoimmune bicytopenia, and 14 (3%) on the basis of autoimmune cytopenia and another SoIEI. Median age at diagnostic evaluation was 9·8 years (IQR 5·5-13·8), and the cohort comprised 279 (65%) boys and 152 (35%) girls. After biomarker and genetic assessments, autoimmune lymphoproliferative syndrome was diagnosed in 71 (16%) patients. Among the remaining 360 patients, 54 (15%) had mostly autosomal-dominant autoimmune lymphoproliferative immunodeficiencies (AD-ALPID), most commonly affecting JAK-STAT (26 patients), CTLA4-LRBA (14), PI3K (six), RAS (five), or NFκB (three) signalling. 19 (5%) patients had other IEIs, 17 (5%) had non-IEI diagnoses, 79 (22%) were unresolved despite extended genetics (ALPID-U), and 191 (53%) had insufficient genetic workup for diagnosis. 16 (10%) of 161 patients with a final diagnosis had somatic mutations. Alternative classification of patients fulfilling common variable immunodeficiency or Evans syndrome criteria did not increase the proportion of genetic diagnoses.

INTERPRETATION

The ALPID phenotype defined in this study is enriched for patients with genetic diseases treatable with targeted therapies. The term ALPID might be useful to focus diagnostic and therapeutic efforts by triggering extended genetic analysis and consideration of targeted therapies, including in some children currently classified as having common variable immunodeficiency or Evans syndrome.

FUNDING

Deutsche Forschungsgemeinschaft under Germany's Excellence Strategy.

TRANSLATION

For the German translation of the abstract see Supplementary Materials section.

Predicting valuable missense variants with AlphaMissense in a multiple pulmonary infection patient

AlphaMissense is proficient in predicting the clinical classification of missense variants. we utilized AlphaMissense to find disease-relevant variants within a polymicrobial pulmonary infection case. Exome sequencing was performed in this patient, and AlphaMissense and Phenolyzer were combined to investigate disease-relevant variants screening from exome sequencing results.

New primary immunodeficiencies 2023 update

PURPOSE OF REVIEW

Primary immunodeficiency diseases (PIDs), also called inborn errors of immunity (IEI), are genetic disorders characterized by increased susceptibility to infection and/or aberrant regulation of immunological pathways. This review summarizes and highlights the new IEI disorders in the International Union of Immunological Societies (IUIS) 2022 report and current trends among new PIDs.

RECENT FINDINGS

Since the 2019 IUIS report and the 2021 IUIS interim update, the IUIS IEI classification now includes 485 validated IEIs. Increasing utilization of genetic testing and advances in the strategic evaluation of genetic variants has continued to drive the identification of, not only novel IEI disorders, but additional genetic etiologies for known IEI disorders and phenotypes.

SUMMARY

The recognition of new IEIs continues to advance at a rapid pace, which is due in part to increased performance and application of genetic modalities as well as expansion of the underlying science that is applied to convincingly establish causality. These disorders, as a whole, continue to emphasize the specificity of immunity, complexity of immune mechanisms, and the fine balance that defines immune homeostasis.

Inborn Errors of Immunity Contribute to the Burden of Skin Disease and Create Opportunities for Improving the Practice of Dermatology

Opportunities to improve the clinical management of skin disease are being created by advances in genomic medicine. Large-scale sequencing increasingly challenges notions about single-gene disorders. It is now apparent that monogenic etiologies make appreciable contributions to the population burden of disease and that they are underrecognized in clinical practice. A genetic diagnosis informs on molecular pathology and may direct targeted treatments and tailored prevention strategies for patients and family members. It also generates knowledge about disease pathogenesis and management that is relevant to patients without rare pathogenic variants. Inborn errors of immunity are a large class of monogenic etiologies that have been well-studied and contribute to the population burden of inflammatory diseases. To further delineate the contributions of inborn errors of immunity to the pathogenesis of skin disease, we performed a set of analyses that identified 316 inborn errors of immunity associated with skin pathologies, including common skin diseases. These data suggest that clinical sequencing is underutilized in dermatology. We next use these data to derive a network that illuminates the molecular relationships of these disorders and suggests an underlying etiological organization to immune-mediated skin disease. Our results motivate the further development of a molecularly derived and data-driven reorganization of clinical diagnoses of skin disease.

Clinical and Treatment History of Patients with Partial DiGeorge Syndrome and Autoimmune Cytopenia at Multiple Centers

BACKGROUND

Patients with partial DiGeorge syndrome (pDGS) can present with immune dysregulation, the most common being autoimmune cytopenia (AIC). There is a lack of consensus on the approach to type, combination, and timing of therapies for AIC in pDGS. Recognition of immune dysregulation early in pDGS clinical course may help individualize treatment and prevent adverse outcomes from chronic immune dysregulation.

OBJECTIVES

Objectives of this study were to characterize the natural history, immune phenotype, and biomarkers in pDGS with AIC.

METHODS

Data on clinical presentation, disease severity, immunological phenotype, treatment selection, and response for patients with pDGS with AIC were collected via retrospective chart review. Flow cytometric analysis was done to assess T and B cell subsets, including biomarkers of immune dysregulation.

RESULTS

Twenty-nine patients with the diagnosis of pDGS and AIC were identified from 5 international institutions. Nineteen (62%) patients developed Evan's syndrome (ES) during their clinical course and twenty (69%) had antibody deficiency syndrome. These patients demonstrated expansion in T follicular helper cells, CD19hiCD21lo B cells, and double negative cells and reduction in CD4 naïve T cells and regulatory T cells. First-line treatment for 17/29 (59%) included corticosteroids and/or high-dose immunoglobulin replacement therapy. Other overlapping therapies included eltrombopag, rituximab, and T cell immunomodulators.

CONCLUSIONS

AIC in pDGS is often refractory to conventional AIC treatment paradigms. Biomarkers may have utility for correlation with disease state and potentially even response to therapy. Immunomodulating therapies could be initiated early based on early immune phenotyping and biomarkers before the disease develops or significantly worsens.

The Inborn Errors of Immunity-Virtual Consultation System Platform in Service for the Italian Primary Immunodeficiency Network: Results from the Validation Phase

PURPOSE

Inborn errors of immunity (IEI) represent a heterogeneous group of rare genetically determined diseases. In some cases, patients present with complex or atypical phenotypes, not fulfilling the accepted diagnostic criteria for IEI and, thus, at high risk of misdiagnosis or diagnostic delay. This study aimed to validate a platform that, through the opinion of immunologist experts, improves the diagnostic process and the level of care of patients with atypical/complex IEI.

METHODS

Here, we describe the functioning of the IEI-Virtual Consultation System (VCS), an innovative platform created by the Italian Immunodeficiency Network (IPINet).

RESULTS

In the validation phase, from January 2020 to June 2021, 68 cases were entered on the IEI-VCS platform. A final diagnosis was achieved in 35/68 cases (51%, 95% CI 38.7 to 64.2). In 22 out of 35 solved cases, the diagnosis was confirmed by genetic analysis. In 3/35 cases, a diagnosis of secondary immunodeficiency was made. In the remaining 10 cases, an unequivocal clinical and immunological diagnosis was obtained, even though not substantiated by genetic analysis.

CONCLUSION

From our preliminary study, the VCS represents an innovative and useful system to improve the diagnostic process of patients with complex unsolved IEI disorders, with benefits both in terms of reduction of time of diagnosis and access to the required therapies. These results may help the functioning of other international platforms for the management of complex cases.

Distinct Immunophenotypic Features in Patients Affected by 22q11.2 Deletion Syndrome with Immune Dysregulation and Infectious Phenotype

The clinical expression of 22q11.2 deletion syndrome (22q11.2 DS) is extremely variable, as patients can present with recurrent or severe infections, immune dysregulation, atopic diseases, or extra-immunological manifestations. The immunological background underlying the different disease manifestations is not completely elucidated. The aim of this study was to identify the immunophenotypic peculiarities of 22q11.2 DS patients presenting with different disease expressions. This study included 34 patients with 22q11.2 DS, divided into three groups according to the clinical phenotype: isolated extra-immunological manifestations (G1), infectious phenotype with increased/severe infections (G2), and immune dysregulation (G3). The patients underwent extended immunophenotyping of the T and B lymphocytes and analysis of the circulating dendritic cells (DCs). In patients with an infectious phenotype, a significant reduction in CD3+ and CD4+ cells and an expansion of CD8 naïve cells was evidenced. On the other hand, the immunophenotype of the patients with immune dysregulation showed a skewing toward memory T cell populations, and reduced levels of recent thymic emigrants (RTEs), while the highest levels of RTEs were detected in the patients with isolated extra-immunological manifestations. This study integrates the current literature, contributing to elucidating the variability in the immune status of patients with 22q11.2DS with different phenotypic expressions, particularly in those with infectious phenotype and immune dysregulation.

Cluster analysis of flowcytometric immunophenotyping with extended T cell subsets in suspected immunodeficiency

BACKGROUND

Patients with immunodeficiencies commonly experience diagnostic delays resulting in morbidity. There is an unmet need to identify patients earlier, especially those with high risk for complications. Compared to immunoglobulin quantification and flowcytometric B cell subset analysis, expanded T cell subset analysis is rarely performed in the initial evaluation of patients with suspected immunodeficiency. The simultaneous interpretation of multiple immune variables, including lymphocyte subsets, is challenging.

OBJECTIVE

To evaluate the diagnostic value of cluster analyses of immune variables in patients with suspected immunodeficiency.

METHODS

Retrospective analysis of 38 immune system variables, including seven B cell and sixteen T cell subpopulations, in 107 adult patients (73 with immunodeficiency, 34 without) evaluated at a tertiary outpatient immunology clinic. Correlation analyses of individual variables, k-means cluster analysis with evaluation of the classification into "no immunodeficiency" versus "immunodeficiency" and visual analyses of hierarchical heatmaps were performed.

RESULTS

Binary classification of patients into groups with and without immunodeficiency was correct in 54% of cases with the full data set and increased to 69% and 75% of cases, respectively, when only 16 variables with moderate (p < .05) or 7 variables with strong evidence (p < .01) for a difference between groups were included. In a cluster heatmap with all patients but only moderately differing variables and a heatmap with only immunodeficient patients restricted to T cell variables alone, segregation of most patients with common variable immunodeficiency and combined immunodeficiency was observed.

CONCLUSION

Cluster analyses of immune variables, including detailed lymphocyte flowcytometry with T cell subpopulations, may support clinical decision making for suspected immunodeficiency in daily practice.

Screening for Antibody Deficiencies in Adults by Serum Electrophoresis and Calculated Globin

PURPOSE

This study aimed to investigate the correlation between calculated globulin (CG, total protein level minus albumin level) and the gamma globulin fraction (Gamma), obtained from serum protein electrophoresis with serum IgG levels in adults (≥ 18 years).

METHODS

Using linear regression models, analyses of CG and Gamma levels correlation with IgG levels in adults were performed. Receiver-operator curves were created to determine cutoff values and the respective sensitivity and specificity measures.

RESULTS

A total of 886 samples were analyzed. CG and Gamma were positively and statistically correlated with IgG levels (r2 = 0.4628 for CG, and = 0.7941 for Gamma, p < 0.0001 for both analyses). For the detection of hypogammaglobulinemia, i.e., IgG level below the reference value (6 g/L), a CG cutoff value of 24 g/L showed a sensitivity of 86.2% (95% CI 69.4-94.5) and a specificity of 92% (90.0-93.6). A Gamma cutoff value of 7.15 g/L yielded a sensitivity of 100% (88.3-100) and a specificity of 96.8 (95.3-97.8).

CONCLUSION

Both CG and Gamma levels determined by protein electrophoresis analysis may be used to screen for antibody deficiencies in adults, enabling earlier diagnosis of antibody deficiencies in a routine clinical setting.

Mycophenolate mofetil for autoimmune cytopenias in children: high rates of response in inborn errors of immunity

Second-line treatments of autoimmune cytopenias (AC) are not well-defined in children. Mycophenolate mofetil (MMF) is an immunosuppressant agent that has been demonstrated to be safe and effective in this setting. A retrospective observational study was conducted in 18 children with prolonged AC who received MMF, in order to describe clinical and biological markers of response. The overall response rate of MMF at 20-30 mg/kg per day was 73.3%. All patients with Evans syndrome (n = 9) achieved complete response. Among the patients with monolineage AC (n = 9), those with an underlying inborn errors of immunity (IEI), tended to respond better to MMF. No biological markers related to treatment response were found. Rather, lymphocyte subpopulations proved useful for patient selection as a marker suggestive of IEI along with immunoglobulin-level determination.

Decline of gastric cancer mortality in common variable immunodeficiency in the years 2018-2022

Introduction

In patients with Common Variable Immunodeficiency, malignancy has been reported as the leading cause of death in adults, with a high risk of B-cell lymphomas and gastric cancer.

Methods

We conducted a five-year prospective study aiming to update the incidence and mortality of gastric cancer and the incidence of gastric precancerous lesions in 512 CVID patients who underwent a total of 400 upper gastrointestinal endoscopies.

Results

In the pre-pandemic period, 0.58 endoscopies were performed per patient/year and in the COVID-19 period, 0.39 endoscopies were performed per patient/year. Histology revealed areas with precancerous lesions in about a third of patients. Patients who had more than one gastroscopy during the study period were more likely to have precancerous lesions. Two patients received a diagnosis of gastric cancer in the absence of Helicobacter pylori infection. The overall prevalence of Helicobacter pylori infection in biopsy specimens was 19.8% and related only to active gastritis. Among patients who had repeated gastroscopies, about 20% progressed to precancerous lesions, mostly independent of Helicobacter pylori.

Discussion

While gastric cancer accounted for one in five deaths from CVID in our previous survey, no gastric cancer deaths were recorded in the past five years, likely consistent with the decline in stomach cancer mortality observed in the general population. However, during the COVID-19 pandemic, cancer screening has been delayed. Whether such a delay or true decline could be the reason for the lack of gastric cancer detection seen in CVID may become clear in the coming years. Due to the high incidence of precancerous lesions, we cannot rely on observed and predicted trends in gastric cancer mortality and strongly recommend tailored surveillance programs.

Activated phosphoinositide 3-kinase δ syndrome: Update from the ESID Registry and comparison with other autoimmune-lymphoproliferative inborn errors of immunity

BACKGROUND

Activated phosphoinositide-3-kinase δ syndrome (APDS) is an inborn error of immunity (IEI) with infection susceptibility and immune dysregulation, clinically overlapping with other conditions. Management depends on disease evolution, but predictors of severe disease are lacking.

OBJECTIVES

This study sought to report the extended spectrum of disease manifestations in APDS1 versus APDS2; compare these to CTLA4 deficiency, NFKB1 deficiency, and STAT3 gain-of-function (GOF) disease; and identify predictors of severity in APDS.

METHODS

Data was collected from the ESID (European Society for Immunodeficiencies)-APDS registry and was compared with published cohorts of the other IEIs.

RESULTS

The analysis of 170 patients with APDS outlines high penetrance and early onset of APDS compared to the other IEIs. The large clinical heterogeneity even in individuals with the same PIK3CD variant E1021K illustrates how poorly the genotype predicts the disease phenotype and course. The high clinical overlap between APDS and the other investigated IEIs suggests relevant pathophysiological convergence of the affected pathways. Preferentially affected organ systems indicate specific pathophysiology: bronchiectasis is typical of APDS1; interstitial lung disease and enteropathy are more common in STAT3 GOF and CTLA4 deficiency. Endocrinopathies are most frequent in STAT3 GOF, but growth impairment is also common, particularly in APDS2. Early clinical presentation is a risk factor for severe disease in APDS.

CONCLUSIONS

APDS illustrates how a single genetic variant can result in a diverse autoimmune-lymphoproliferative phenotype. Overlap with other IEIs is substantial. Some specific features distinguish APDS1 from APDS2. Early onset is a risk factor for severe disease course calling for specific treatment studies in younger patients.

Paediatric-onset Evans syndrome: Breaking away from refractory immune thrombocytopenia

Since its first description by Evans in 1951, this syndrome has been linked to chronic immune thrombocytopenia with the concurrent or delayed onset of autoimmune haemolytic anaemia or neutropenia. For decades, the evolution of Evans syndrome (ES) has carried a poor prognosis and often resulted in chronic steroid exposure, multiple immune suppressing medications directed against T or B lymphocytes, and splenectomy. This paper presents a new view of ES based on recent advances in genomics which begin to classify patients based on their underlying molecular variants in previously described primary immune disorders. This has opened up new avenues of targeted therapy or bone marrow transplant at rather than broad long-term immune suppression or splenectomy. Importantly, recent studies of the full lifespan of ES suggest that at least 80% of those paediatric patients will progress to various clinical or biological immunopathological manifestations with age despite the resolution of their cytopenias. Those patients merit long-term follow-up and monitoring in dedicated transition programs to improve outcome at the adult age.