Advances in primary immunodeficiency diseases in Latin America: epidemiology, research, and perspectives

Facing the challenges to shorten the diagnostic odyssey: first Whole Genome Sequencing experience of a Colombian cohort with suspected rare diseases

Exome and genome sequencing (ES/GS) are routinely used for the diagnosis of genetic diseases in developed countries. However, their implementation is limited in countries from Latin America. We aimed to describe the results of GS in patients with suspected rare genetic diseases in Colombia. We studied 501 patients from 22 healthcare sites from January to December 2022. GS was performed in the index cases using dried blood spots on filtercards. Ancestry analysis was performed under iAdmix. Multiomic testing was performed when needed (biomarker, enzymatic activity, RNA-seq). All tests were performed at an accredited genetic laboratory. Ethnicity prediction data confirmed that 401 patients (80%) were mainly of Amerindian origin. A genetic diagnosis was established for 142 patients with a 28.3% diagnostic yield. The highest diagnostic yield was achieved for pathologies with a metabolic component and syndromic disorders (p < 0.001). Young children had a median of 1 year of diagnostic odyssey, while the median time for adults was significantly longer (15 years). Patients with genetic syndromes have spent more than 75% of their life without a diagnosis, while for patients with neurologic and neuromuscular diseases, the time of the diagnostic odyssey tended to decrease with age. Previous testing, specifically karyotyping or chromosomal microarray were significantly associated with a longer time to reach a definitive diagnosis (p < 0.01). Furthermore, one out of five patients that had an ES before could be diagnosed by GS. The Colombian genome project is the first Latin American study reporting the experience of systematic use of diagnostic GS in rare diseases.

CD40 Ligand Deficiency in Latin America: Clinical, Immunological, and Genetic Characteristics

CD40 ligand (CD40L) deficiency is a rare inborn error of immunity presenting with heterogeneous clinical manifestations. While a detailed characterization of patients affected by CD40L deficiency is essential to an accurate diagnosis and management, information about this disorder in Latin American patients is limited. We retrospectively analyzed data from 50 patients collected by the Latin American Society for Immunodeficiencies registry or provided by affiliated physicians to characterize the clinical, laboratory, and molecular features of Latin American patients with CD40L deficiency. The median age at disease onset and diagnosis was 7 months and 17 months, respectively, with a median diagnosis delay of 1 year. Forty-seven patients were genetically characterized revealing 6 novel mutations in the CD40LG gene. Pneumonia was the most common first symptom reported (66%). Initial immunoglobulin levels were variable among patients. Pneumonia (86%), upper respiratory tract infections (70%), neutropenia (70%), and gastrointestinal manifestations (60%) were the most prevalent clinical symptoms throughout life. Thirty-five infectious agents were reported, five of which were not previously described in CD40L deficient patients, representing the largest number of pathogens reported to date in a cohort of CD40L deficient patients. The characterization of the largest cohort of Latin American patients with CD40L deficiency adds novel insights to the recognition of this disorder, helping to fulfill unmet needs and gaps in the diagnosis and management of patients with CD40L deficiency.

Awareness of primary immunodeficiency diseases at a national pediatric reference center in Peru

Objective

To investigate the level of awareness of primary immunodeficiency diseases among physicians working at Instituto Nacional de Salud del Niño.

Methods

Cross-sectional study including pediatric residents and pediatricians working at the Instituto Nacional de Salud del Niño during the study period (2017-2019). Physicians working at the immunology unit and surgery departments were excluded. Three aspects of awareness of primary immunodeficiency diseases were investigated: education, general knowledge, and diagnostic suspicion and actions taken in the face of suspicion.

Results

This sample comprised 83 physicians with a median age of 33 years. Most physicians were women (71.1%) and half were pediatric residents. During their undergraduate studies, 43.1% had taken primary immunodeficiency disease courses, and 39.2% had attended conferences on this topic. During their residency training, 25.9% had taken primary immunodeficiency disease courses, and 60.3% had participated in conferences on this topic. Among pediatricians, 50% had taken primary immunodeficiency disease courses, and 53.1% had attended conferences on this topic. Only 39.8% of physicians reported being familiar with the list of 10 warning signs developed by the Jeffrey Modell Foundation. More than half of physicians considered the lack of access to laboratory tests the major challenge in making diagnosis of primary immunodeficiency diseases.

Conclusion

This study revealed limited awareness of primary immunodeficiency diseases among physicians working at Instituto Nacional de Salud del Niño. Although most physicians suspected primary immunodeficiency diseases in patients with a history of recurrent infections and frequent use of antibiotics, not all of them were familiar with the list of 10 warning signs proposed by the Jeffrey Modell Foundation, nor were they able to describe ancillary tests requested in suspected cases.

Primary Immunodeficiencies in India: Molecular Diagnosis and the Role of Next-Generation Sequencing

Primary immunodeficiency diseases (PIDs) are a group of clinically and genetically heterogeneous disorders showing ethnic and geographic diversities. Next-generation sequencing (NGS) is a comprehensive tool to diagnose PID. Although PID is common in India, data on the genetic spectrum of PIDs are limited due to financial restrictions. The study aims to characterize the clinical and genetic spectrum of PID patients in India and highlight the importance of a cost-effective targeted gene panel sequencing approach for PID in a resource-limited setting. The study includes 229 patients with clinical and laboratory features suggestive of PIDs. Mutation analysis was done by Sanger sequencing and NGS targeting a customized panel of genes. Pathogenic variants were identified in 97 patients involving 42 different genes with BTK and IL12RB1 being the most common mutated genes. Autosomal recessive and X-linked recessive inheritance were seen in 51.6% and 23.7% of patients. Mendelian susceptibility to mycobacterial diseases (MSMD) and IL12RB1 mutations was more common in our population compared to the Western world and the Middle East. Two patients with hypomorphic RAG1 mutations and one female with skewed CYBB mutation were also identified. Another 40 patients had variants classified as variants of uncertain significance (VUS). The study shows that targeted NGS is an effective diagnostic strategy for PIDs in countries with limited diagnostic resources. Molecular diagnosis of PID helps in genetic counseling and to make therapeutic decisions including the need for a stem cell transplantation.

Availability of secondary healthcare data for conducting pharmacoepidemiology studies in Colombia: A systematic review

Real-world evidence (RWE) is emerging as a fundamental component of the post-marketing evaluation of medicinal products. Even though the focus on RWE studies has increased in Colombia, the availability of secondary data sources to perform this type of research is not well documented. Thus, we aimed at identifying and characterizing secondary data sources available in Colombia. We performed a systematic literature review on PubMed, EMBASE, and VHL using a combination of controlled vocabulary and keywords for the concepts of electronic health records, epidemiologic studies and Colombia. A total of 323 publications were included. These comprised 123 identified secondary data sources including pharmacy dispensing databases, government datasets, disease registries, insurance databases, and electronic heath records, among others. These data sources were mostly used for cross-sectional studies focused on disease epidemiology in a specific population. Almost all databases (95%) contained demographic information, followed by pharmacological treatment (44%) and diagnostic tests (39%). Even though the database owner was identifiable in 94%, access information was only available in 44% of the articles. Only a pharmacy-dispensing database, local cancer registries, and government databases included a description regarding the quality of the information available. The diversity of databases identified shows that Colombia has a high potential to continue enhancing its RWE strategy. Greater efforts are required to improve data quality and accessibility. The linkage between databases will expand data pooling and integration to boost the translational potential of RWE.

Frequency and Manifestations of Autoimmunity Among Children Registered in the Kuwait National Primary Immunodeficiency Registry

Objectives: To present a prospective report on the characteristics of autoimmune manifestations in patients with primary immunodeficient children registered in the Kuwait National PIDs Registry (KNPIDR).

Methods: The data were obtained from the Kuwait National Primary Immunodeficiency Disorders Registry during the period of January 2004 to December 2019.

Results: A total of 286 PID children were registered in KNPIDR during the study period with a predominance of immunodeficiencies affecting cellular and humoral immunity followed by combined immunodeficiencies with associated syndromic features and diseases of immune dysregulation. Fifty-seven (19.9%) patients presented with a total of 107 autoimmune manifestations. There was no significant statistical association between autoimmune manifestations and gender. Patients with autoimmune manifestations were older at onset of PID symptoms compared to those with no such manifestations, but this did not reach level of significance. The diagnosis delay was longer in patients with autoimmune manifestations compared to those with no such manifestations (p = 0.038). Forty-seven percent of these manifestations were among the presenting symptoms while 53% were documented later during the course of the disease. Fifty-seven percent of the patients developed 1 autoimmune manifestation, 30% developed 2 such manifestations, and 16% had ≥3 autoimmune manifestations. The most common autoimmune manifestation was cytopenia, followed by gastrointestinal manifestations and manifestations of the skin, hair, and nails. Autoimmune cytopenia were more common in patients with immune dysregulation syndromes, while gastrointestinal and skin manifestations predominate in patients with immunodeficiencies affecting cellular and humoral immunity and endocrine manifestations were more common in immune dysregulation syndromes. There were significant statistical associations between developing autoimmune manifestations and death as well as PID categories, being more common in patients with immune dysregulation. The frequency of autoimmunity was high among patients with RAG, WAS, STAT5b, NF-κB2, Fas, FasL, LRBA, APECED, IL-10, and C4 deficiencies.

Conclusions: Autoimmunity is frequent in patients with PIDs in Kuwait. This should prompt the suspicion of a PID in patients who present initially with autoimmunity, especially autoimmune cytopenia. Such patients should be managed with extra care since they are at a higher risk of death.

Association between primary immunodeficiency and asthma exacerbation in adult asthmatics

BACKGROUND/AIMS

Primary immunodef iciency (PID) is a serious comorbid condition in adult asthmatics that have frequent exacerbations, which requires monthly replacement of intravenous immunoglobulin (IVIG). However, the prevalence and clinical significance of PID in adult asthmatics in Korea have not yet been reported. The aim of this study is to assess the prevalence of PID and its association with asthma exacerbation in Korean adult asthmatics.

METHODS

A total of 2,866 adult asthmatics were enrolled in this study. The PID group was defined as subjects who had lower levels of immunoglobulin G (IgG)/ A/M and/or IgG subclass presenting with recurrent respiratory infections. Serum samples were assayed for total IgG/A/M by immunoturbidimetry, and IgG subclasses by nephelometry.

RESULTS

Of the 2,866 asthmatic patients enrolled, 157 (5.49%) had PID (classified as the PID group), while those without PID was classified as the non-PID group. IgG subclass deficiency (58%) is most prevalent, among which IgG3 subclass deficiency was most common (58%). The relative risk of asthma exacerbation was 1.70 times higher in the PID group compared to the non-PID group (1.696; 95% confidence interval, 1.284 to 2.239; p < 0.001); the prevalence of severe asthma was significantly higher in the PID group than in the non-PID group (32.48% vs. 13.00%, p < 0.001). Thirty-five among 157 patients in the PID group d maintained IVIG to prevent asthma exacerbation.

CONCLUSION

It is suggested that PID, especially IgG3 subclass deficiency, is a significant risk factor for asthma exacerbation. Screening of IgG subclass levels and IVIG replacement should be considered in the management in adult asthmatics.

Selection of Blood, Blood Components, and Blood Products as Essential Medicines in 105 Low- and Middle-Income Countries

Blood products of human origin are essential treatment options for several diseases, for example, hemophilia. We studied the alignment of national essential medicines lists (NEMLs) of low- and middle-income countries (LMICs) with the World Health Organization (WHO) Model List for the selection of blood products of human origin. The most recent versions of NEMLs from all LMICs were studied for the inclusion of blood products of human origin (blood and blood components, plasma products, and immunoglobulins). Data obtained from 105 NEMLs were compared to the 2017 WHO Model List. The median number of blood products of human origin on the NEMLs was 4 (range: 0-10). Immunoglobulins were most frequently included (73%). Blood and blood components were the least selected products (15%). The uptake of plasma products was around 50%. Nine countries did not have any blood products of human origin on their NEMLs. Some NEMLs included blood products not listed on the WHO Model List (albumin, hepatitis A immunoglobulin, and cryoprecipitate). We observed variation in selection according to WHO region, income level, and year of NEML update. Alignment of NEMLs with the WHO Model List varied greatly for different groups of blood products, ranging from good uptake for immunoglobulins, reasonable uptake for plasma products, to poor uptake for blood and blood components. This heterogeneity in selection and inclusion of blood products of human origin on NEMLs may be partly explained as being due to specific country characteristics, but some of it may not be explained. Policy makers need to rely on evidence in making decisions about which blood products to select, include, and remove on their NEMLs.

The Kuwait National Primary Immunodeficiency Registry 2004-2018

Objective: To present the report from the Kuwait National Primary Immunodeficiency Registry between 2004 and 2018. Methods: The patients were followed prospectively between January 2004 and December 2018 and their collected data included sociodemographic, diagnosis, clinical presentation, laboratory tests, and treatment. Results: A total of 314 PID patients (165 males and 149 females) were registered during the study period. Most of the patients (n = 287, 91.4%) were Kuwaiti nationals and the prevalence among Kuwaitis was 20.27/100,000 with a cumulative incidence of 24.96/100,000 Kuwaitis. The distribution of the patients according to PID categories was as follow: immunodeficiencies affecting cellular and humoral immunity, 100 patients (31.8%); combined immunodeficiencies with associated syndromic features, 68 patients (21.7%); predominantly antibody deficiencies, 56 patients (17.8%); diseases of immune dysregulation, 47 patients (15%); congenital defects of phagocyte number or function, 20 patients (6.4%); autoinflammatory disorders, 1 patient (0.3%); and complement deficiencies, 22 patients (7%). The mean age of the patients at onset of symptoms was 26 months while the mean age at diagnosis was 53 months and the mean delay in diagnosis was 27 months. Most of the patients (n = 272, 86%) had onset of symptoms before the age of 5 years. Parental consanguinity rate within the registered patients was 78% and a positive family history of PID was noticed in 50% of the patients. Genetic testing was performed in 69% of the patients with an overall diagnostic yield of 90%. Mutations were identified in 46 different genes and more than 90% of the reported genetic defects were transmitted by an autosomal recessive pattern. Intravenous immunoglobulins and stem cell transplantation were used in 58% and 25% of the patients, respectively. There were 81 deaths (26%) among the registered patients with a mean age of death of 25 months. Conclusions: PID is not infrequent in Kuwait and the reported prevalence is the highest in the literature with increased proportion of more severe forms. Collaborative efforts including introduction of newborn screening should be implemented to diagnose such cases earlier and improve the quality of life and prevent premature deaths.

Comprehensive Genetic Results for Primary Immunodeficiency Disorders in a Highly Consanguineous Population

Objective: To present the genetic causes of patients with primary immune deficiencies (PIDs) in Kuwait between 2004 and 2017.

Methods: The data was obtained from the Kuwait National Primary Immunodeficiency Disorders Registry. Genomic DNA from patients with clinical and immunological features of PID was sequenced using Sanger sequencing (SS), next generation sequencing (NGS) of targeted genes, whole exome sequencing (WES), and/or whole genome sequencing (WGS). Functional assays were utilized to assess the biologic effect of identified variants. Fluorescence in situ hybridization (FISH) for 22q11.2 deletion and genomic hybridizations arrays were performed when thymic defects were suspected.

Results: A total of 264 patients were registered during the study period with predominance of patients with immunodeficiencies affecting cellular and humoral immunity (35.2%), followed by combined immunodeficiencies with associated syndromic features (24%). Parental consanguinity and family history suggestive of PID were reported in 213 (81%) and 145 patients (55%), respectively. Genetic testing of 206 patients resulted in a diagnostic yield of 70%. Mutations were identified in 46 different genes and more than 90% of the reported genetic defects were transmitted by in an autosomal recessive pattern. The majority of the mutations were missense mutations (57%) followed by deletions and frame shift mutations. Five novel disease-causing genes were discovered.

Conclusions: Genetic testing should be an integral part in the management of primary immunodeficiency patients. This will help the delivery of precision medicine and facilitate proper genetic counseling. Studying inbred populations using sophisticated diagnostic methods can allow better understanding of the genetics of primary immunodeficiency disorders.

Primary immunodeficiency diseases in a tuberculosis endemic region: challenges and opportunities

While individual primary immunodeficiency diseases (PIDs) are rare, collectively they represent a significant burden of disease. Recent estimates show that about one million people in Africa suffer from a PID. However, data from African PID registries reflect only a small percentage of the estimated prevalence. This disparity is partly due to the lack of PID awareness and the masking of PIDs by the endemic pathogens. Over three million tuberculosis (TB) cases were reported in Africa in 2016, with many of these from southern Africa. Despite concerted efforts to address this high burden of disease, the underlying genetic correlates of susceptibility to TB remain poorly understood. High penetrance mutations in immune system genes can cause PIDs that selectively predispose individuals to TB and other mycobacterial diseases. Additionally, the identification of individuals at a heightened risk of developing TB or of presenting with severe or disseminated TB due to their genetic ancestry is crucial to promote a positive treatment outcome. The screening for and identification of PID mutations in TB-endemic regions by next-generation sequencing (NGS) represents a promising approach to improve the understanding of what constitutes an effective immune response to TB, as well as the range of associated PIDs and phenotypes.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies

In the last few years, new primary immunodeficiencies and genetic defects have been described. Recently, immunoglobulin products with improved compositions and for subcutaneous use have become available in Brazil. In order to guide physicians on the use of human immunoglobulin to treat primary immunodeficiencies, based on a narrative literature review and their professional experience, the members of the Primary Immunodeficiency Group of the Brazilian Society of Allergy and Immunology prepared an updated document of the 1^st Brazilian Consensus, published in 2010. The document presents new knowledge about the indications and efficacy of immunoglobulin therapy in primary immunodeficiencies, relevant production-related aspects, mode of use (routes of administration, pharmacokinetics, doses and intervals), adverse events (major, prevention, treatment and reporting), patient monitoring, presentations available and how to have access to this therapeutic resource in Brazil.

Severe Enteropathy and Hypogammaglobulinemia Complicating Refractory Mycobacterium tuberculosis Complex Disseminated Disease in a Child with IL-12Rβ1 Deficiency

PURPOSE

Mendelian susceptibility to mycobacterial disease is a rare clinical condition characterized by a predisposition to infectious diseases caused by poorly virulent mycobacteria. Other infections such as salmonellosis and candidiasis are also reported. The purpose of this article is to describe a young boy affected with various infectious diseases caused by Mycobacterium tuberculosis complex, Salmonella sp, Klebsiella pneumonie, Citrobacter sp., and Candida sp, complicated with severe enteropathy and transient hypogammaglobulinemia.

METHODS

We reviewed medical records and performed flow cytometry staining for lymphocyte populations, lymphocyte proliferation in response to PHA, and intracellular IFN-γ production in T cell PHA blasts in the patient and a healthy control. Sanger sequencing was used to confirm the genetic variants in the patient and relatives.

RESULTS

Genetic analysis revealed a bi-allelic mutation in IL12RB1 (C291Y) resulting in complete IL-12Rβ1 deficiency. Functional analysis demonstrated the lack of intracellular production of IFN-γ in CD3+ T lymphocytes from the patient in response to rhIL-12p70.

CONCLUSIONS

To our knowledge, this is the third patient with MSMD due to IL-12Rβ1 deficiency complicated with enteropathy and hypogammaglobulinemia and the first case of this disease to be described in Colombia.

Uses of Next-Generation Sequencing Technologies for the Diagnosis of Primary Immunodeficiencies

Primary immunodeficiencies (PIDs) are genetic disorders impairing host immunity, leading to life-threatening infections, autoimmunity, and/or malignancies. Genomic technologies have been critical for expediting the discovery of novel genetic defects underlying PIDs, expanding our knowledge of the complex clinical phenotypes associated with PIDs, and in shifting paradigms of PID pathogenesis. Once considered Mendelian, monogenic, and completely penetrant disorders, genomic studies have redefined PIDs as a heterogeneous group of diseases found in the global population that may arise through multigenic defects, non-germline transmission, and with variable penetrance. This review examines the uses of next-generation DNA sequencing (NGS) in the diagnosis of PIDs. While whole genome sequencing identifies variants throughout the genome, whole exome sequencing sequences only the protein-coding regions within a genome, and targeted gene panels sequence only a specific cohort of genes. The advantages and limitations of each sequencing approach are compared. The complexities of variant interpretation and variant validation remain the major challenge in wide-spread implementation of these technologies. Lastly, the roles of NGS in newborn screening and precision therapeutics for individuals with PID are also addressed.

Primary immunodeficiencies in Chile evaluated through ICD-10 coded hospital admissions

BACKGROUND

The epidemiology and hospitalisation trends of primary immunodeficiency (PID) in Chile are unknown. We aimed to evaluate hospitalisation trends and demographic characteristics of PID admissions in Chile.

METHODS

PID admissions between 2001 and 2010 (ICD-10 codes D70.0, D70.4, D71, 72.0, D76.1, D80-D84, E70.3, G11.3) were reviewed using national hospital discharge databases.

RESULTS

During the study period, 5486 admissions due to PID were registered (0.03% of total). 58.5% of patients were male and 66.3% were under 18 years. Median length of stay was one day (range 1-403 days). The most frequent diagnoses were hypogammaglobulinaemia (27.6%), unspecified immunodeficiency (21.9%), haemophagocytic lymphohystiocytosis (18.3%) and common variable immunodeficiency (11.2%). There was a significant increase in PID admission rate and in one-day hospitalisations during this period (β=0.2; P=0.001 and β=33; P≤0.001, respectively), however no significant variation was found for longer admissions (β=4.8; P=0.175). The increasing trend in PID admission rate was significant in patients with private, but not public insurance (β=0.53; P≤0.001 vs. β=0.08; P=0.079, respectively).

CONCLUSIONS

We report an increasing trend in admissions due to PID in Chile over a 10-year period. Increase is mainly due to short hospitalisations, possibly accounting for improvements in IVIG access. Higher admission rates in patients with private vs. public insurance suggest socioeconomic disparities in access to PID treatment. ICD-10 coded hospitalisation databases may be useful to determine hospitalisation trends and demographic characteristics of PID admissions worldwide.

Variations of B cell subpopulations in peripheral blood of healthy Mexican population according to age: Relevance for diagnosis of primary immunodeficiencies

BACKGROUND

Peripheral blood B cells include lymphocytes at various stages of differentiation, each with a specific function in the immune response. All these stages show variations in percentage and absolute number throughout human life. The numbers and proportions of B subpopulation are influenced by factors such as gender, age, ethnicity, and lifestyle. This study establishes reference values according to age of peripheral blood B cell subtypes in healthy Mexican population.

METHODS

Peripheral blood from healthy new-borns and adults were analysed for total B cell subpopulations, using surface markers such as CD19, IgM, IgD, CD21, CD24, CD27, and CD38, to identify naïve, memory with and without isotype switch, double-negative, transitional, and plasmablast cells.

RESULTS

We observed a significant variation in terms of frequency and absolute counts between all groups analysed. Values from each B cell subpopulation show variations according to age.

CONCLUSIONS

In order to attempt to elucidate reference values for B cell subpopulation, the present study evaluated a population sample of healthy blood donors from this region. Values reported here can also be used as a tool for diagnosis of diseases in which B cell maturation is affected.

Clinical and Genotypic Spectrum of Chronic Granulomatous Disease in 71 Latin American Patients: First Report from the LASID Registry

AIM

We analyzed data from 71 patients with chronic granulomatous disease (CGD) with a confirmed genetic diagnosis, registered in the online Latin American Society of Primary Immunodeficiencies (LASID) database.

RESULTS

Latin American CGD patients presented with recurrent and severe infections caused by several organisms. The mean age at disease onset was 23.9 months, and the mean age at CGD diagnosis was 52.7 months. Recurrent pneumonia was the most frequent clinical condition (76.8%), followed by lymphadenopathy (59.4%), granulomata (49.3%), skin infections (42%), chronic diarrhea (41.9%), otitis (29%), sepsis (23.2%), abscesses (21.7%), recurrent urinary tract infection (20.3%), and osteomyelitis (15.9%). Adverse reactions to bacillus Calmette-Guérin (BCG) vaccination were identified in 30% of the studied Latin American CGD cases. The genetic diagnoses of the 71 patients revealed 53 patients from 47 families with heterogeneous mutations in the CYBB gene (five novel mutations: p.W361G, p.C282X, p.W483R, p.R226X, and p.Q93X), 16 patients with the common deletion c.75_76 del.GT in exon 2 of NCF1 gene, and two patients with mutations in the CYBA gene.

CONCLUSION

The majority of Latin American CGD patients carry a hemizygous mutation in the CYBB gene. They also presented a wide range of clinical manifestations most frequently bacterial and fungal infections of the respiratory tract, skin, and lymph nodes. Thirty percent of the Latin American CGD patients presented adverse reactions to BCG, indicating that this vaccine should be avoided in these patients.

Primary Immunodeficiency Diseases in Saudi Arabia: a Tertiary Care Hospital Experience over a Period of Three Years (2010-2013)

PURPOSE

Primary immunodeficiencies (PID) are a group of heterogeneous diseases. Epidemiological studies from databases worldwide show geographical variation. In this study the objective is to determine the spectrum of PID in Saudi Arabia by analyzing the database in a referral tertiary hospital.

METHODS

This is a prospective data collection by interviews and medical chart review for all PID patients followed at the King Faisal Specialist Hospital & Research Center (KFSH&RC) from May 2010 to April 2013.

RESULTS

A total of 502 patients presented (53 % male and 47 % female). Combined immunodeficiencies were the most common (59.7 %), followed by predominantly antibody deficiencies (12.3 %), congenital defects of phagocyte (9.4 %), combined immunodeficiencies with associated or syndromic features (6.2 %), disease of immune dysregulation (6 %), complement deficiencies (5.8), and defects in innate immunity (0.6 %). The most common combined immunodeficiencies phenotype was T-B-SCID (17 %). The patients' ages ranged from less than 1 year old to 78 years, and 394 patients (78.2 %) are in the paediatrics age group (<14 years). The overall mean age of symptoms onset was 17 months and the overall mean delay in diagnosis was 21.6 months. Recurrent infections were the most common occurring clinical presentation (66 %), followed by family history (26 %). Consanguinity was found in 75 % of the patients. A total of 308 (61 %) patients had undergone stem cell transplantation (SCT).

CONCLUSION

The study revealed that combined immunodeficiencies are not uncommon and are the most frequent occurring diagnosis in our patient population. This study is a prerequisite to establish a national registry of primary immunodeficiency in Saudi Arabia.

Current state and future perspectives of the Latin American Society for Immunodeficiencies (LASID)

Primary immunodeficiencies (PID) are genetic diseases that affect the immune system and for the last 20 years, the Latin American Society for Immunodeficiencies (LASID) has been promoting initiatives in awareness, research, diagnosis, and treatment for the affected patients in Latin America. These initiatives have resulted in the development of programmes such as the LASID Registry (with 4900 patients registered as of January 2014), fellowships in basic and clinical research, PID summer schools, biannual meetings, and scientific reports, amongst others. These achievements highlight the critical role that LASID plays as a scientific organisation in promoting science, research and education in this field in Latin America. However, challenges remain in some of these areas and the Society must envision additional strategies to tackle them for the benefit of the patients. In June 2013, a group of experts in the field met to discuss the contributions of LASID to the initiatives of PID in Latin America, and this article summarises the current state and future perspectives of this society and its role in the advance of PIDs in Latin America.

The use of databases in primary immunodeficiencies

PURPOSE OF REVIEW

We provide an overview on the latest developments in primary immunodeficiency registries worldwide, on the basis of the recent literature amended by some older references to achieve completeness.

RECENT FINDINGS

New primary immunodeficiency registries are emerging worldwide, although existing databases continue to thrive and provide valuable insights for clinicians and researchers.

SUMMARY

In the area of rare disease research, data on a meaningful number of patients can only be achieved via collaboration. Registries for primary immunodeficiency are organized on different geographic levels and appear in various technical forms. Some registries are operated within single departments or hospitals, whereas others collect data from a country in the form of a national registry. With modern information technology and networks, it has become feasible to easily extend documentation to the transnational level. Most patient registries cover similar but not identical sets of data, whereas some have a special focus on, for example, genetics or incorporate only data from patients who have undergone a specific form of treatment. This review shows the usefulness and power of international immunodeficiency registries, as well as possible hurdles and limitations.

Doctors' awareness concerning primary immunodeficiencies in Brazil

BACKGROUND

PIDs are a heterogeneous group of genetic illnesses, and delay in their diagnosis is thought to be caused by a lack of awareness among physicians concerning PIDs. The latter is what we aimed to evaluate in Brazil.

METHODS

Physicians working at general hospitals all over the country were asked to complete a 14-item questionnaire. One of the questions described 25 clinical situations that could be associated with PIDs and a score was created based on percentages of appropriate answers.

RESULTS

A total of 4026 physicians participated in the study: 1628 paediatricians (40.4%), 1436 clinicians (35.7%), and 962 surgeons (23.9%). About 67% of the physicians had learned about PIDs in medical school or residency training, 84.6% evaluated patients who frequently took antibiotics, but only 40.3% of them participated in the immunological evaluation of these patients. Seventy-seven percent of the participating physicians were not familiar with the warning signs for PIDs. The mean score of correct answers for the 25 clinical situations was 48.08% (±16.06). Only 18.3% of the paediatricians, 7.4% of the clinicians, and 5.8% of the surgeons answered at least 2/3 of these situations appropriately.

CONCLUSIONS

There is a lack of medical awareness concerning PIDs, even among paediatricians, who have been targeted with PID educational programmes in recent years in Brazil. An increase in awareness with regard to these disorders within the medical community is an important step towards improving recognition and treatment of PIDs.

Medical awareness concerning primary immunodeficiency diseases in the city of São Paulo, Brazil

OBJECTIVE

To evaluate medical knowledge of primary immunodeficiency in the city of São Paulo (SP).

METHODS

A 14-item questionnaire about primary immunodeficiency was applied to physicians who worked at general hospitals. One of the questions presented 25 clinical situations that could be associated or not with primary immunodeficiency, and the percentage of appropriate answers generated a knowledge indicator.

RESULTS

Seven hundred and forty-six participated in the study, among them 215 pediatricians (28.8%), 244 surgeons (32.7%), and 287 clinicians (38.5%). About 70% of the physicians responded that they had learned about primary immunodeficiency in graduate school or in residency training. Treatment of patients that use antibiotics frequently was reported by 75% dos physicians, but only 34.1% had already investigated a patient and 77.8% said they did not know the ten warning signs for primary immunodeficiency. The knowledge indicator obtained showed a mean of 45.72% (±17.87). Only 26.6% if the pediatricians and 6.6% of clinicians and surgeons showed a knowledge indicator of at least 67% (equivalent to an appropriate answer in two thirds of the clinical situations).

CONCLUSION

There is a deficit in medical knowledge of primary immunodeficiency in the city of São Paulo, even among pediatricians, despite having greater contact with the theme over the last few years. The improvement of information on primary immunodeficiency in the medical community is an important step towards the diagnosis and treatment process of these diseases.

Gene correction of induced pluripotent stem cells derived from a murine model of X-linked chronic granulomatous disorder

Gene therapy presents an attractive alternative to allogeneic haematopoietic stem cell transplantation (HSCT) for treating patients suffering from primary immunodeficiency disorder (PID). The conceptual advantage of gene correcting a patient's autologous HSCs lies in minimizing or completely avoiding immunological complications arising from allogeneic transplantation while conferring the same benefits of immune reconstitution upon long-term engraftment. Clinical trials targeting X-linked chronic granulomatous disorder (X-CGD) have shown promising results in this context. However, long-term clinical benefits in these patients have been limited by issues of poor engraftment of gene-transduced cells coupled with transgene silencing and vector induced clonal proliferation. Novel vectors incorporating safety features such as self-inactivating (SIN) mutations in the long terminal repeats (LTRs) along with synthetic promoters driving lineage-restricted sustainable expression of the gp91phox transgene are expected to resolve the current pitfalls and require rigorous preclinical testing. In this chapter, we have outlined a protocol in which X-CGD mouse model derived induced pluripotent stem cells (iPSCs) have been utilized to develop a platform for investigating the efficacy and safety profiles of novel vectors prior to clinical evaluation.

Pediatric allergy and immunology in Brazil

The subspecialty of pediatric allergy and immunology in Brazil is in its early years and progressing steadily. This review highlights the research developed in the past years aiming to show the characteristics of allergic and immunologic diseases in this vast country. Epidemiologic studies demonstrated the high prevalence of asthma in infants, children, and adolescents. Mortality rates and average annual variation of asthma hospitalization have reduced in all pediatric age groups. Indoor aeroallergen exposure is excessively high and contributes to the high rates of allergy sensitization. Prevalence of food allergy has increased to epidemic levels. Foods (35%), insect stings (30%), and drugs (23%) are the main etiological agents of anaphylaxis in children and adolescents. Molecular diagnosis of primary immunodeficiencies (PID) showed a high incidence of fungal infections including paracoccidioidomycosis in X-linked hyper-IgM syndrome, and the occurrence of BCG adverse reactions or other mycobacterial infections in patients with chronic granulomatous disease. Education in pediatric allergy and immunology is deficient for medical students, but residency programs are effective in training internists and pediatricians for the practice of allergy. The field of PID requires further training. Last, this review is a tribute to Prof. Dr. Charles Naspitz, one of the pioneers of our specialty in Brazil.

Primary immunodeficiency diseases in different age groups: a report on 1,008 cases from a single Brazilian reference center

Primary immunodeficiencies (PIDs) represent a large group of diseases that affect all age groups. Although PIDs have been recognized as rare diseases, there is epidemiological evidence suggesting that their real prevalence has been underestimated. We performed an evaluation of a series of 1,008 infants, children, adolescents and adults with well-defined PIDs from a single Brazilian center, regarding age at diagnosis, gender and PID category according to the International Union of Immunological Societies classification. Antibody deficiencies were the most common category in the whole series (61 %) for all age groups, with the exception of <2-year-old patients (only 15 %). In the >30-year-old group, antibody deficiencies comprised 84 % of the diagnoses, mostly consisting of common variable immunodeficiency, IgA deficiency and IgM deficiency. Combined immunodeficiencies represented the most frequent category in <2-years-old patients. Most congenital defects of phagocytes were identified in patients <5 -years of age, as were the diseases of immune dysregulation, with the exception of APECED. DiGeorge syndrome and ataxia-telangiectasia were the most frequent entities in the category of well-defined syndromes, which were mostly identified in patients <10-years of age. Males represented three-quarters and two-thirds of <2 -years-old and 2-5-years -old patients, respectively, whereas females predominated among the >30-year-old patients. Our data indicated that some PIDs were only detected at early ages, likely because affected patients do not survive long. In addition, our data pointed out that different strategies should be used to search for PIDs in infants and young children as compared to older patients.

Advancing the management of primary immunodeficiency diseases in Latin America: Latin American Society for Immunodeficiencies (LASID) Initiatives

Primary immunodeficiency diseases (PIDD) are associated with significant morbidity and mortality and result in a significant public health burden. This is in part due to the lack of appropriate diagnosis and treatment of these patients. It is critical that governments become aware of this problem and provide necessary resources to reduce this impact on health care systems. Leading physicians in their respective countries must be supported by their own governments in order to implement tools and provide education and thus improve the diagnosis and treatment of PIDD. The Latin American Society of Primary Immunodeficiencies (LASID) has initiated a large number of activities aimed at achieving these goals, including the establishment of a PIDD registry, development of educational programmes and guidelines, and the introduction of a PIDD fellowship programme. These initiatives are positively impacting the identification and appropriate treatment of patients with PIDD in Latin America. Nevertheless, much remains to be done to ensure that every person with PIDD receives proper therapy.