A Nationwide Study of the Delayed Diagnosis and the Clinical Manifestations of Predominantly Antibody Deficiencies and CTLA4-Mediated Immune Dysregulation Syndrome in Greece.

Background and Objectives: Predominantly antibody deficiencies (PAD) represent the most common type of primary immunodeficiencies in humans, characterized by a wide variation in disease onset, clinical manifestations, and outcome. Considering that the prevalence of PAD in Greece is unknown, and there is limited knowledge on the clinical and laboratory characteristics of affected patients, we conducted a nationwide study. Materials and Methods: 153 patients (male/female: 66/87; median age: 43.0 years; range: 7.0-77.0) diagnosed, and followed-up between August 1979 to September 2023. Furthermore, we classified our cohort into five groups according to their medical history, immunoglobulin levels, and CTLA4-mutational status: 123 had common variable immunodeficiency (CVID), 12 patients with "secondary" hypogammaglobulinemia due to a previous B-cell depletion immunotherapy for autoimmune or malignant disease several years ago (median: 9 years, range 6-14) displaying a typical CVID phenotype, 7 with combined IgA and IgG subclass deficiencies, 5 patients with CVID-like disease due to CTLA4-mediated immune dysregulation syndrome, and 6 patients with unclassified hypogammaglobulinemia. Results: We demonstrated a remarkable delay in PAD diagnosis, several years after the onset of related symptoms (median: 9.0 years, range: 0-43.0). A family history of PAD was only present in 11.8%, with the majority of patients considered sporadic cases. Most patients were diagnosed in the context of a diagnostic work-up for recurrent infections, or recurrent/resistant autoimmune cytopenias. Interestingly, 10 patients (5.6%) had no history of infection, diagnosed due to either recurrent/resistant autoimmunity, or during a work-up of their medical/family history. Remarkable findings included an increased prevalence of lymphoproliferation (60.1%), while 39 patients (25.5%) developed bronchiectasis, and 16 (10.5%) granulomatous disease. Cancer was a common complication in our cohort (25 patients, 16.3%), with B-cell malignancies representing the most common neoplasms (56.7%). Conclusion: Our findings indicate the necessity of awareness about PAD and their complications, aiming for early diagnosis and the appropriate management of affected patients.

Cancer Prevalence in Children with Inborn Errors of Immunity: Report from a Single Institution.

BACKGROUND: Inborn Errors of Immunity (IEI) comprise several genetic anomalies that affect different components of the innate and adaptive responses, predisposing to infectious diseases, autoimmunity and malignancy. Different studies, mostly in adults, have reported a higher prevalence of cancer in IEI patients. However, in part due to the rarity of most of these IEI subtypes (classified in ten categories by the Primary Immunodeficiency Committee of the International Union of Immunological Societies), it is difficult to assess the risk in a large number of patients, especially during childhood. OBJECTIVE: To document the cancer prevalence in a pediatric cohort from a single referral institution, assessing their risk, together with the type of neoplasia within each IEI subgroup. METHOD: An extensive review of clinical records from 1989 to 2022 of IEI patients who at some point developed cancer before the age of sixteen. RESULTS: Of a total of 1642 patients with IEI diagnosis, 34 developed cancer before 16 years of age, showing a prevalence (2.1%) significantly higher than that of the general age matched population (0.22). Hematologic neoplasms (mostly lymphomas) were the most frequent malignancies. CONCLUSION: This study represents one of the few reports focused exclusively in pediatric IEI cases, describing not only the increased risk of developing malignancy compared with the age matched general population (a fact that must be taken into account by immunologists during follow-up) but also the association of the different neoplasms with particular IEI subtypes, thus disclosing the possible mechanisms involved.

Association between serum IgG concentrations and the incidence of infections in patients with chronic lymphocytic leukemia and secondary immunodeficiency under treatment with Privigen.

OBJECTIVE: To investigate the association between serum immunoglobulin G (IgG) concentrations and the incidence of infections in patients with chronic lymphocytic leukemia (CLL) and secondary immunodeficiency receiving treatment with Privigen. MATERIALS AND METHODS: Data was analyzed from a non-interventional study conducted in 31 centers in Germany and 1 in Austria. Adult CLL patients with hypogammaglobulinemia and recurrent infections were allowed to enter the study upon signing informed consent, if a prior decision for treatment with Privigen had been made. All infections requiring an antimicrobial treatment were subject to analysis. Patients were stratified according to their mean post-baseline serum IgG trough levels in a group with lower IgG trough levels (≤ 5.0 g/L), and a group with higher IgG trough levels (> 5.0 g/L). RESULTS: Overall, 89 patients and 840 treatment cycles were analyzed. Up to 11 treatment cycles (average duration 29 days) were documented in each patient. In the group with higher IgG trough levels (> 5.0 g/L, N = 72), significantly fewer infections were observed than in the group with lower IgG trough levels (≤ 5.0 g/L, N = 17), including fewer severe and serious infections. The Privigen dosage was a major determinant of the post-baseline serum IgG levels. Overall tolerability of Privigen was assessed as very good or good in 91% of patients. CONCLUSION: This analysis confirms the association of serum IgG trough levels with the incidence of infections and highlights the importance of careful monitoring of IgG levels during treatment of secondary immunodeficiencies in CLL patients.

Evaluation of the Effectiveness of the 6 Warning Signs of the European Society for Immunodeficiencies for Primary Immunodeficiencies in Older Adults.

INTRODUCTION: Diagnostic delay in cases of primary immunodeficiency (PID) is a significant problem for clinicians, and most do not have sufficient awareness of this uncommon disorder. The European Society for Immunodeficiencies (ESID) has developed 6 warning signs to increase awareness of adult PIDs. The aim of this study was to determine the prevalence of PID in older adults regardless of the reason for presentation and to evaluate the effectiveness of the 6 warning signs of ESID in the diagnosis of PIDs. METHODS: The study included 1,331 patients aged ≥65 years who presented at our clinic for any reason and were questioned about the ESID 6 warning signs for PIDs. After the exclusion of reasons for secondary immunodeficiency (SID), all the patients underwent immunological evaluation for the diagnosis of potential underlying PIDs. RESULTS: After excluding 6 patients diagnosed with SID, PID was diagnosed in 16 (1.2%) of 1,325 older adults using ESID warning signs. The most common reasons for presentation were infection (69%) in the PID group and urticaria and/or angioedema (41.5%) in the non-PID group. The most common PID subgroup was common variable immunodeficiency (50%). In 12 of the patients diagnosed with PID, there was at least 1 positive ESID warning sign. In 4 patients, PID was determined despite negative ESID warning signs. The patients diagnosed with PID showed a significant, minimal level of agreement with questions 1 and 4 of the ESID warning signs (p < 0.001, ĸ = 0.204, p = 0.005, ĸ = 0.208, respectively). CONCLUSION: The ESID warning signs do not encompass all the symptoms and findings of PIDs. There is a need for more infection-centered questions to determine PIDs in older adults. Therefore, the ESID warning signs should be further developed.

The Association Between Malignancy, Immunodeficiency, and Atopy in IgE-Deficient Patients.

BACKGROUND: Studies show that IgE-deficient patients (IgE <2.5 kU/L) have a high prevalence of malignancy, but relevant clinical and laboratory characteristics associated with this susceptibility have never been well characterized. OBJECTIVE: To evaluate if there is an association between a malignancy diagnosis and other immunological parameters (atopy or other immune abnormalities) in IgE-deficient patients. METHODS: We retrospectively analyzed medical records of 408 IgE-deficient adults seen at our institution between 2005 and 2020. RESULTS: A malignancy diagnosis was found in 23.5% (96 of 408) of IgE-deficient patients. Among those who had allergy skin testing performed for allergic rhinitis-like symptoms, the nonatopic IgE-deficient patients (negative environmental skin tests) were more likely to have a malignancy diagnosis than the atopic group (odds ratio [OR] = 4.36, 95% confidence interval [CI]: 1.11-17.13, P = .03). The IgE-deficient individuals with an additional non-common variable immunodeficiency (non-CVID) humoral abnormality (n = 75; with low IgG, IgA, or IgM without meeting criteria for CVID) were more likely to have a malignancy diagnosis than those with only a selective IgE deficiency (n = 134; with normal IgA, IgM, and IgG) (OR = 2.79, 95% CI: 1.37-5.68, P = .005). Among the IgE-deficient patients, certain less well-defined immune abnormalities such as IgM deficiency (OR = 2.46, 95% CI: 1.13-5.36, P = .02), IgG2 deficiency (OR = 10.14, 95% CI: 1.9-54.1, P = .007), and CD4 lymphopenia (OR = 7.81, 95% CI: 2.21-27.63, P = .001) were associated with higher malignancy odds than those without these abnormalities. CONCLUSION: The odds of a malignancy diagnosis are not shared equally by all IgE-deficient patients. Prospective studies are needed to determine the utility of performing skin testing and measuring additional immunological parameters in assessing the long-term malignancy risk in IgE-deficient patients.

Characteristics and Outcomes of Anti-interferon Gamma Antibody-Associated Adult Onset Immunodeficiency.

PURPOSE: Anti-interferon gamma antibody (AIGA) is a rare cause of adult onset immunodeficiency, leading to severe disseminated opportunistic infections with varying outcomes. We aimed to summarize the disease characteristics and to explore factors associated with disease outcome. METHODS: A systematic literature review of AIGA associated disease was conducted. Serum-positive cases with detailed clinical presentations, treatment protocols, and outcomes were included. The patients were categorized into controlled and uncontrolled groups based on their documented clinical outcome. Factors associated with disease outcome were analyzed with logistic regression models. RESULTS: A total of 195 AIGA patients were retrospectively analyzed, with 119(61.0%) having controlled disease and 76 (39.0%) having uncontrolled disease. The median time to diagnosis and disease course were 12 months and 28 months, respectively. A total of 358 pathogens have been reported with nontubercular mycobacterium (NTM) and Talaromyces marneffei as the most common pathogens. The recurrence rate was as high as 56.0%. The effective rates of antibiotics alone, antibiotics with rituximab, and antibiotics with cyclophosphamide were 40.5%, 73.5%, and 75%, respectively. In the multivariate logistic analysis, skin involvement, NTM infection, and recurrent infections remained significantly associated with disease control, with ORs of 3.25 (95% CI 1.187 ~ 8.909, P value = 0.022), 4.74 (95% CI 1.300 ~ 17.30, P value = 0.018), and 0.22 (95% CI 0.086 ~ 0.551, P value = 0.001), respectively. The patients with disease control had significant AIGA titer reduction. CONCLUSIONS: AIGA could cause severe opportunistic infections with unsatisfactory control, particularly in patients with recurrent infections. Efforts should be made to closely monitor the disease and regulate the immune system.

Poliovirus surveillance in patients with primary immunodeficiencies, India.

Individuals with primary immunodeficiencies who are infected with vaccine-derived polioviruses may continue to shed poliovirus for months and go undetected by surveillance programmes of acute flaccid paralysis. These patients therefore pose a risk of initiating poliovirus outbreaks that jeopardize efforts towards global polio eradication. To identify these individuals, we designed a study protocol for the establishment of a network for surveillance of immunodeficiency-related vaccine-derived poliovirus in India. In the first step we identified recognized centres in India that could diagnose and enrol patients with primary immunodeficiency disorder into the study. Stool sample collection from study sites, culture, isolation, characterization of enteroviruses and reporting to study sites was carried out at the National Institute of Virology Mumbai Unit, as per the WHO national polio surveillance project protocol. In the first phase of the study from January 2020 to December 2021, we implemented the protocol at seven study sites at different medical institutes to determine the proportion of poliovirus infections in primary immunodeficiency disorder patients of India. We later expanded the study by including an additional 14 medical institutes across the country in the second phase running from January 2022 to December 2023. We believe this study protocol will help other countries to initiate immunodeficiency-related vaccine-derived poliovirus surveillance to identify and follow up patients who are long-term excretors of vaccine-derived poliovirus. Integration of immunodeficiency-related poliovirus surveillance with acute flaccid paralysis surveillance of the existing poliovirus network will enhance continuous screening of patients with primary immunodeficiency disorder in the future.

Certains individus qui présentent des immunodéficiences primaires et sont infectés par des poliovirus dérivés d'une souche vaccinale pourraient continuer à excréter le poliovirus pendant des mois sans que ce dernier ne soit détecté par le biais d'une surveillance de la paralysie flasque aiguë. Ces patients risquent donc de déclencher des épidémies de poliovirus qui mettent en péril les efforts visant à éradiquer la poliomyélite dans le monde. En vue d'identifier ces individus, nous avons élaboré un protocole d'étude pour établir, en Inde, un réseau de surveillance du poliovirus d'origine vaccinale lié à une immunodéficience. Au cours de la première étape, nous avons repéré des centres reconnus dans le pays, capables de diagnostiquer des patients atteints d'un syndrome d'immunodéficience primaire et de les recruter dans le cadre de l'étude. Le prélèvement des échantillons de selles auprès des sites participant à l'étude, la culture, l'isolement, la caractérisation des entérovirus et la communication des résultats à ces sites ont été pris en charge par le National Institute of Virology Mumbai Unit, conformément au protocole du Projet national de surveillance de la poliomyélite de l'OMS. Nous avons consacré la première phase de l'étude, qui s'est déroulée entre janvier 2020 et décembre 2021, à la mise en œuvre du protocole au sein de différents établissements médicaux sur sept sites participants, afin de déterminer le nombre d'infections au poliovirus chez les patients souffrant d'un syndrome d'immunodéficience primaire en Inde. Nous avons ensuite, durant la deuxième phase comprise entre janvier 2022 et décembre 2023, élargi l'étude en incluant 14 établissements supplémentaires à travers le pays. Nous sommes convaincus que ce protocole d'étude aidera d'autres pays à instaurer une surveillance du poliovirus dérivé d'une souche vaccinale et lié à une immunodéficience, qui leur servira à identifier et suivre les patients responsables d'une excrétion prolongée du poliovirus d'origine vaccinale. L'intégration, au sein du réseau existant dédié au poliovirus, d'une surveillance de ce type couplée à une surveillance de la paralysie flasque aiguë améliorera le dépistage systématique des patients atteints d'un syndrome d'immunodéficience primaire à l'avenir.

Las personas con inmunodeficiencias primarias infectadas por los poliovirus de origen vacunal pueden seguir excretando poliovirus durante meses sin que la vigilancia de la parálisis flácida aguda los detecte. Por lo tanto, estos pacientes suponen un riesgo de iniciar brotes de poliovirus que pongan en peligro los esfuerzos hacia la erradicación mundial de la poliomielitis. Para identificar a estas personas, diseñamos un protocolo de estudio para el establecimiento de una red de vigilancia de poliovirus de origen vacunal relacionados con inmunodeficiencias en la India. En el primer paso identificamos centros reconocidos en la India que pudieran diagnosticar e inscribir en el estudio a pacientes con trastorno de inmunodeficiencia primaria. La recogida de muestras de heces de los centros de estudio, el cultivo, el aislamiento, la caracterización de los enterovirus y la notificación a los centros de estudio se llevaron a cabo en el Instituto Nacional de Virología, Unidad de Mumbai, según el protocolo del Proyecto Nacional de Vigilancia de la Poliomielitis de la OMS. En la primera fase del estudio, de enero de 2020 a diciembre de 2021, aplicamos el protocolo en siete centros de estudio de diferentes institutos médicos para determinar la proporción de infecciones por poliovirus en pacientes con trastorno de inmunodeficiencia primaria de la India. A continuación, ampliamos el estudio con la inclusión de otros 14 institutos médicos de todo el país en la segunda fase, de enero de 2022 a diciembre de 2023. Creemos que este protocolo de estudio ayudará a otros países a iniciar la vigilancia de poliovirus de origen vacunal relacionados con la inmunodeficiencia para identificar y hacer un seguimiento de los pacientes que son excretores a largo plazo de poliovirus de origen vacunal. La integración de la vigilancia del poliovirus asociado a la inmunodeficiencia con la vigilancia de la parálisis flácida aguda de la red de poliovirus existente mejorará el cribado continuo de pacientes con trastorno por inmunodeficiencia primaria en el futuro.

Pregnancy in primary immunodeficiency diseases: The PREPI study.

BACKGROUND: Primary immunodeficiencies (PID) are a heterogeneous group of rare inborn immunity defects. As management has greatly improved, morbidity and mortality are reduced in this population, while our knowledge on pregnancy's unfolding and outcome remains scarce. OBJECTIVE: We conducted a retrospective monocentric study to study pregnancy outcomes in women with PID. METHODS: The study cohort consisted of women over 18 included in the national registry for PID (CEREDIH), living in the greater Paris area, reporting ≥1 pregnancy. Data were collected through a standardized questionnaire and medical records. We analyzed PID features, pregnancy course and outcome, and neonatal features (NCT04581460). RESULTS: We studied 93 women with PID (27 combined immunodeficiencies, 51 predominantly antibody deficiencies, and 15 innate immunodeficiencies) and their 222 pregnancies (67, 119, and 36 in each group, respectively). One hundred fifty-four (69%) of 222 pregnancies led to 157 live births, including 4 severe preterm births (3%), in the range of pregnancy outcome in the French general population. In a multivariate model, poor obstetrical outcome (fetal loss or pregnancy termination) was associated with history of severe infection (adjusted odds ratio 0.28, 95% confidence interval 0.11-0.67, P = .005). Only 59% pregnancies were led with optimal anti-infective prophylaxis; severe infections were reported in only 2 pregnancies (1%). One infant died during the neonatal period. CONCLUSION: Pregnancy is achievable in women with a wide group of PID. Prematurity is increased and history of severe infection is associated with significant increase of fetal loss/pregnancy termination. Adjustment of care during pregnancy needs to be better delivered.

Allogeneic Hematopoietic Stem Cell Transplantation Activity in Inborn Errors of Immunity in Russian Federation.

PURPOSE: Allogeneic hematopoietic stem cell transplantation (HSCT) is an established therapy for many inborn errors of immunity (IEI). The indications for HSCT have expanded over the last decade. The study aimed to collect and analyze the data on HSCT activity in IEI in Russia. METHODS: The data were collected from the Russian Primary Immunodeficiency Registry and complemented with information from five Russian pediatric transplant centers. Patients diagnosed with IEI by the age of 18 years and who received allogeneic HSCT by the end of 2020 were included. RESULTS: From 1997 to 2020, 454 patients with IEI received 514 allogeneic HSCT. The median number of HSCTs per year has risen from 3 in 1997-2009 to 60 in 2015-2020. The most common groups of IEI were immunodeficiency affecting cellular and humoral immunity (26%), combined immunodeficiency with associated/syndromic features (28%), phagocyte defects (21%), and diseases of immune dysregulation (17%). The distribution of IEI diagnosis has changed: before 2012, the majority (65%) had severe combined immunodeficiency (SCID) and hemophagocytic lymphohistiocytosis (HLH), and after 2012, only 24% had SCID and HLH. Of 513 HSCTs, 48.5% were performed from matched-unrelated, 36.5% from mismatched-related (MMRD), and 15% from matched-related donors. In 349 transplants T-cell depletion was used: 325 TCRαß/CD19+ depletion, 39 post-transplant cyclophosphamide, and 27 other. The proportion of MMRD has risen over the recent years. CONCLUSION: The practice of HSCT in IEI has been changing in Russia. Expanding indications to HSCT and SCID newborn screening implementation may necessitate additional transplant beds for IEI in Russia.

Reactive Neutrophilic Dermatoses in Adult-Onset Immunodeficiency due to Interferon-Gamma Autoantibody and Their Associated Factors.

BACKGROUND: Adult-onset immunodeficiency (AOID) due to interferon-gamma autoantibody is a rare, acquired immunodeficiency disease. Reactive neutrophilic dermatoses (RND), predominantly Sweet syndrome (SS), and generalized pustular eruption have been reported repeatedly. OBJECTIVES: The aims of this study were to describe the cutaneous manifestations in AOID patients and determine the incidence of RND and associated factors using a larger population size than have been previously reported. METHODS: A retrospective chart review of all confirmed AOID cases in Chiang Mai University Hospital from January 2006 to June 2020 was conducted. The demographics and characteristics of RND including type, onset, and laboratory information in every episode of cutaneous manifestations were collected. Generalized estimating equations of binary logistic regression were used to determine the indicators of RND. RESULTS: A total of 146 patients with confirmed AOID were identified. Of these, 57 cases (39%) developed at least one episode of RND. Thirteen cases (23%) of the patients experienced RND twice during the follow-up period. All recurrence of RND displayed the same cutaneous phenotype, with the exception of 2 cases who had both SS and generalized pustular eruption. Finally, 49 episodes of SS and 22 episodes of generalized pustular eruption were included in the analysis. All patients with RND had concomitant active opportunistic infections, of which most were non-tuberculous mycobacterium (NTM) infection. NTM infection (prevalence odds ratio [POR] 2.87), lymphadenopathy (POR 3.30) as well as lower serum alkaline phosphatase (ALP) level (POR 0.71 for every 100-unit increment in ALP) were found to be significantly associated with RND occurrence. CONCLUSIONS: 39% of our AOID patients experienced RND once during the course of the disease. Notable factors associated with RND occurrence were concomitant NTM infection, lymphadenopathy, and lower level of ALP.

How do nuclear factor kappa B (NF-κB)1 and NF-κB2 defects lead to the incidence of clinical and immunological manifestations of inborn errors of immunity?

INTRODUCTION: Genetic defects affect the manner of the immune system's development, activation, and function. Nuclear factor-kappa B subunit 1 (NF-κB1) and NF-κB2 are involved in different biological processes, and deficiency in these transcription factors may reveal clinical and immunological difficulties. AREAS COVERED: This review article gathers the most frequent clinical and immunological remarkable characteristics of NF-κB1 and NF-κB2 deficiencies. Afterward, an effort is made to describe the biological mechanism, which is likely to be the cause of these clinical and immunological abnormalities. EXPERT OPINION: The present review article has explained the mechanism of contributions of the NF-κB1 and NF-κB2 deficiency in revealing immunodeficiency symptoms, specifically immunological and clinical manifestations. These mechanisms demonstrate the importance of NF-κB1 and NF-κB2 signaling pathways for B and T cell development, activation, antibody production, and immunotolerance. The manifestation of a mutation can range from no symptoms to severe complications in a family.

NF-κB1 and NF-κB2 are the transcription factors that have an essential role in the development and function of the immune system. Several mutations in the NF-κBs could lead to inborn errors of immune manifestations.There are different reports of NF-κB mutations with various clinical and immunological manifestations, whereas the mechanisms behind the appearance of these have been less discussed. We collected frequent clinical and immunological manifestations from the literature and discussed the likely biological cause of their occurrence. Here we clarify the potential mechanism that defects in NF-κB1 and NF-κB2 signaling lead to inadequate B and T cells function, specifically, insufficient switched memory B cells and class-switched antibodies and autoimmunity. We also focused on the straight correlation between deficiencies in immune system responses caused by defects in NF-κB and susceptibility to recurrent infections and other clinical problems.Since our understanding of the mechanisms of signaling pathways such as NF-κB deficiencies from genetic mutations to clinical manifestations in PIDs is limited, further in vitro and animal model studies are necessary to assess these pathways' comprehensive roles in immunodeficiency more accurately. [Figure: see text].

Current Transition Practice for Primary Immunodeficiencies and Autoinflammatory Diseases in Europe: a RITA-ERN Survey.

BACKGROUND: Due to the absence of curative treatments for inborn errors of immunity (IEI), children born with IEI require long-term follow-up for disease manifestations and related complications that occur over the lifespan. Effective transition from pediatric to adult services is known to significantly improve adherence to treatment and long-term outcomes. It is currently not known what transition services are available for young people with IEI in Europe. OBJECTIVE: To understand the prevalence and practice of transition services in Europe for young people with IEI, encompassing both primary immunodeficiencies (PID) and systemic autoinflammatory disorders (AID). METHODS: A survey was generated by the European Reference Network on immunodeficiency, autoinflammatory, and autoimmune diseases Transition Working Group and electronically circulated, through professional networks, to pediatric centers across Europe looking after children with IEI. RESULTS: Seventy-six responses were received from 52 centers, in 45 cities across 17 different countries. All services transitioned patients to adult services, mainly to specialist PID or AID centers, typically transferring up to ten patients to adult care each year. The transition process started at a median age of 16-18 years with transfer to the adult center occurring at a median age of 18-20 years. 75% of PID and 68% of AID centers held at least one joint appointment with pediatric and adult services prior to the transfer of care. Approximately 75% of PID and AID services reported having a defined transition process, but few centers reported national disease-specific transition guidelines to refer to. CONCLUSIONS: Transition services for children with IEI in Europe are available in many countries but lack standardized guidelines to promote best practice.

High Frequency of Specific Polysaccharide Antibody Deficiency in Adults With Unexplained, Recurrent and/or Severe Infections With Encapsulated Bacteria.

BACKGROUND: Primary immunodeficiencies (PIDs) in adults are mainly revealed by recurrent and/or severe bacterial infections. The objective of this study was to evaluate a systematic research strategy of PIDs in adults with unexplained bacterial infections, with a special focus on specific polysaccharide antibody deficiency (SPAD). METHODS: In this prospective multicenter study, inclusion criteria were recurrent benign upper and lower respiratory tract infections (RTIs) for at least two years (group 1), at least one upper or lower RTI requiring hospitalization (group 2), and/or at least one invasive infection documented with encapsulated bacteria (group 3). Main exclusion criteria were all local and general conditions that could explain infections. If no PID diagnosis was made, response to polysaccharide antigens was assessed using a pneumococcal polysaccharide vaccine. RESULTS: From March 2015 to March 2020, 118 patients were included (37 males, median age of 41 years): 73, 17, and 28 in groups 1, 2, and 3, respectively. Forty-seven PIDs were diagnosed, giving an estimated frequency of 39.8% (95% confidence interval [CI] [30.4, 48.8]). SPAD was the most frequent diagnosis by far (n = 37/47, 78.7%), and was made in 23, 5, and 9 patients from groups 1 to 3, respectively. All SPAD patients received conjugate vaccines and, according to their infectious history, were on surveillance or treated with preventive antibiotics (n = 6) and/or with immunoglobulins replacement therapy (n = 10), the latter being dramatically efficient in all cases. CONCLUSIONS: Considering its high prevalence among adults with unexplained recurrent and/or severe bacterial infections, SPAD should be screened in those patients. CLINICAL TRIALS REGISTRATION: NCT02972281.

The spectrum of inborn errors of immunity: a single tertiary center retrospective study in Alborz, Iran.

Summary: Background. Inborn errors of immunity (IEIs) are a group of heterogeneous disorders with inherited faults in the immune system that increase susceptibility to infections, malignancies, lymphoproliferation, and autoimmune/autoinflammatory disorders. Methods. We retrospectively studied the demographic characteristics, clinical features, and immunological profiles of the 90 IEIs patients, who were diagnosed and classified according to the European Society for Immunodeficiencies (ESID) and International Union of Immunological Societies (IUIS) criteria from July 2010 to June 2021. The study was carried out in the Non-communicable Diseases Research Center, Imam Ali Hospital, Alborz, Iran. Results. Within a period of 11 years, 53 (58.9%) males and 37 (41.1%) females were diagnosed and followed up for 20 IEI disorders. The median (IQR) age of onset, age of clinical diagnosis and diagnostic delay was 0.7 (0.08-2.0), 3.18 (1.0-8.0) and 1.5 (0.17-5.0) years, respectively. Twelve patients (36.4%) had a positive family history of IEI, and the majority of patients (84.5%) had recurrent infections. Pneumonia (51.7%) was the most common clinical manifestation among IEI patients, followed by skin complications (46.2%). The most frequently diagnosed IEI was immunoglobulin A deficiency (IgAD) (14.4%) and severe combined immunodeficiency (SCID) (11.1%). Predominantly antibody deficiencies group (36.7%) was the most common category, followed by combined immunodeficiencies with associated or syndromic features group (27.8%). Conclusions. IEIs have different patterns within populations with high consanguinity. There is a need to search for underlying genetic and epigenetic factors in most common IEIs in Alborz.

Knowledge, awareness, and perception on genetic testing for primary immunodeficiency disease among parents in Malaysia: a qualitative study.

Background: Primary Immunodeficiency Disease (PID), also known as Inborn Errors of Immunity (IEI), comprises a group of rare genetic disorders that impair the body's immune responses. These conditions result from monogenic germline mutations that affect the function of genes governing the innate and adaptive immune system. Therefore, individuals with PID are more susceptible to infectious diseases, allergies, and autoimmune and autoinflammatory conditions. The prevalence of PID has been on the rise, with the number of classified diseases reaching 404, and 430 genetic defects reported to cause these conditions. However, in Malaysia, genetic testing for PID is currently limited and needs to be outsourced to overseas laboratories, posing financial challenges for families. Moreover, limited research has focused on the knowledge and awareness of genetic testing among parents of children with PID in Malaysia. This study aims to address this gap and provide valuable insights into the knowledge, awareness, and perception of genetic testing among this specific population. Method: This qualitative cross-sectional study utilised online open-ended, semi-structured focus group interviews to explore the perceptions and experiences of parents of children with Primary Immunodeficiency (PID). Participants were recruited through convenience sampling from the Malaysian Patient Organisation for Primary Immunodeficiencies (MyPOPI), a non-governmental organisation dedicated to providing support and raising awareness about PID. The study spanned from May 2023 to July 2023 and included participants from diverse regions of Malaysia who had undergone different diagnostic journeys in various hospitals. Result: The focus group discussions yielded 11 sub-themes that highlighted the experiences, understanding and challenges of the participants regarding genetic testing based on the semi-structured questions. These sub-themes were then grouped into four main themes that are awareness and understanding of genetic testing, the journey towards diagnosis and treatment, emotional impact and psychological factors, and the importance of medical experts in diagnosing and managing PID, as well as public perception and awareness. Conclusion: In conclusion, this study highlights the diverse knowledge, awareness, and perception surrounding genetic testing for PID. Factors such as access to services, family history, and personal circumstances shape individuals' understanding of genetic testing. The importance of healthcare professionals, along with the need for improved accessibility and targeted communication strategies, is underscored to enhance understanding and reduce stigma surrounding genetic testing for rare diseases like PID.

Disease Progression of WHIM Syndrome in an International Cohort of 66 Pediatric and Adult Patients.

Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome (WS) is a combined immunodeficiency caused by gain-of-function mutations in the C-X-C chemokine receptor type 4 (CXCR4) gene. We characterize a unique international cohort of 66 patients, including 57 (86%) cases previously unreported, with variable clinical phenotypes. Of 17 distinct CXCR4 genetic variants within our cohort, 11 were novel pathogenic variants affecting 15 individuals (23%). All variants affect the same CXCR4 region and impair CXCR4 internalization resulting in hyperactive signaling. The median age of diagnosis in our cohort (5.5 years) indicates WHIM syndrome can commonly present in childhood, although some patients are not diagnosed until adulthood. The prevalence and mean age of recognition and/or onset of clinical manifestations within our cohort were infections 88%/1.6 years, neutropenia 98%/3.8 years, lymphopenia 88%/5.0 years, and warts 40%/12.1 years. However, we report greater prevalence and variety of autoimmune complications of WHIM syndrome (21.2%) than reported previously. Patients with versus without family history of WHIM syndrome were diagnosed earlier (22%, average age 1.3 years versus 78%, average age 5 years, respectively). Patients with a family history of WHIM syndrome also received earlier treatment, experienced less hospitalization, and had less end-organ damage. This observation reinforces previous reports that early treatment for WHIM syndrome improves outcomes. Only one patient died; death was attributed to complications of hematopoietic stem cell transplantation. The variable expressivity of WHIM syndrome in pediatric patients delays their diagnosis and therapy. Early-onset bacterial infections with severe neutropenia and/or lymphopenia should prompt genetic testing for WHIM syndrome, even in the absence of warts.

[Antibodydeficiencies Epidemiology, Clinical manifestation, Diagnostics and Therapy]. / Antikörpermangelsyndrome.

Antibodydeficiencies Epidemiology, Clinical manifestation, Diagnostics and Therapy Abstract. Primary Immune Deficiencies (PID) are caused by a genetically induced malformation/dysfunction of the immune system. Leading symptoms include susceptibility to infection, autoimmune diseases, lymphoproliferative, allergic as well as malignant diseases. They can be divided into ten main groups, including the primary antibody deficiency syndromes (PAD) in adults. The most well-known PADs include the variable immunodeficiency syndrome (CVID), Bruton's agammaglobulinaemia, IgG subclass deficiencies, immunoglobulin A deficiency, Antibody deficiency and transient childhood hypogammaglobulinaemia. Secondary hypogammaglobulinaemia by medicinal products, haematological diseases, malignancies and infections should be excluded. Delayed diagnosis of CVID is associated with a significant increase in morbidity and an increase in mortality. In addition to vaccinations, immunoglobulin replacement therapy is used therapeutically.

Risk Factors of Pneumonia in Primary Antibody Deficiency Patients Receiving Immunoglobulin Therapy: Data from the US Immunodeficiency Network (USIDNET).

BACKGROUND: Despite immunoglobulin replacement (IgRT) therapy, some patients with primary antibody deficiency (PAD) continue to develop respiratory infections. Recurrent and severe respiratory infections, particularly pneumonia, can lead to significant morbidity and mortality. Therefore, we sought to determine the risk factors of developing pneumonia in PAD patients, already receiving IgRT. METHODS: We evaluated clinical and laboratory features of PAD patients enrolled in the US Immune Deficiency Network (USIDNET) registry by April 2017. Patients were included if they met the following criteria: (1) PAD diagnosis (common variable immunodeficiency (CVID), agammaglobulinemia, hypogammaglobinemia, and specific antibody deficiency (SAD) and (2) available data on infections before and after IgRT. Patients were excluded if they were not receiving IgRT, or if no pre/post infections data were available. Descriptive and multivariable logistic regression analyses were used to identify factors associated with pneumonia post-IgRT. RESULTS: A total of 1232 patients met the inclusion criteria. Following IgRT, 218 patients (17.7%) were reported to have at least one pneumonia episode. Using multivariate logistic regression analysis, we found a statistically significant increased risk of pneumonia in patients with asthma (OR: 2.55, 95% CI (1.69-3.85), p < 0.001) bronchiectasis (OR: 3.94, 95% CI (2.29-6.80), p < 0.001), interstitial lung disease (ILD) (OR: 3.28, 95%CI (1.43-7.56), p < 0.005), splenomegaly (OR: 2.02, 95%CI (1.08-3.76), p < 0.027), allergies (OR: 2.44, 95% CI [1.44-4.13], p = 0.001), and patients who were not on immunosuppressives (OR: 1.61; 95%CI [1.06-2.46]; p = 0.027). For every 50 unit increase in IgA, the odds of reporting pneumonia post IgRT decreased (OR: 0.86, 95% CI [0.73-1.02], p = 0.062). Infectious organisms were reported in 35 of 218 patients who reported pneumonia after IgRT. Haemophilus influenzae was the most frequently reported (n = 11, 31.43%), followed by Streptococcus pneumoniae (n = 7, 20.00%). CONCLUSION: Our findings suggest PAD patients with chronic and structural lung disease, splenomegaly, and allergies were associated with persistent pneumonia. However, our study is limited by the cross-sectional nature of the USIDNET database and limited longitudinal data. Further studies are warranted to identify susceptible causes and explore targeted solutions for prevention and associated morbidity and mortality. CLINICAL IMPLICATIONS: Patients with primary antibody deficiency with structural lung disease, allergies, and splenomegaly are associated with persistent pneumonia post-IgRT.

Algerian Registry for Inborn Errors of Immunity in Children: Report of 887 Children (1985-2021).

INTRODUCTION: Inborn errors of immunity (IEI) represent a heterogeneous large group of genetic disorders characterized by susceptibility of affected individuals to recurrent infections, autoimmune/inflammatory diseases, allergy, and malignancy. We aimed to report for the first time the Algerian registry for IEI in children. METHODS: We described the characteristics of IEI in Algerian children from the data collected in the Algerian registry for IEI between 1985 and 2021. RESULTS: Over a period of 37 years, we included 887 children (530 male, 59.6%) with a mean age at diagnosis of 3.23 years and a mean diagnosis delay of 2 years. The prevalence rate was estimated at 1.97/100,000 inhabitants or 5.91/100,000 children. The parental consanguinity was found in 52.6%. The most prevalent category was combined immunodeficiencies (CID) (35.5%), followed by predominantly antibody deficiencies (24.5%) and CID with syndromic features (18.3%). The most predominant diseases were severe CID (134 cases), MHC II deficiency (99 cases), agammaglobulinemia (82 cases), common variable immunodeficiency (78 cases), hyper IgE syndromes (61 patients), ataxia-telangiectasia (46 patients), Wiskott-Aldrich syndrome (40 patients) and chronic granulomatous disease (39 cases). The clinical presentation was dominated by lower respiratory tract infections (69%), failure to thrive (38.3%), and chronic diarrhea (35.2%). Genetic analysis was performed in 156 patients (17.6%). The global mortality rate was 28.4% mainly caused by CID. CONCLUSION: This is the first report of the Algerian registry for IEI in children. Data is globally similar to that of the Middle East and North African (MENA) registries with high consanguinity, predominance of CID, and significant mortality. This registry highlights the weak points that should be improved in order to provide better patient care.