[Autoimmunity and Freiburg classification in common variable immunodeficiency]. / Autoinmunidad y clasificación de Freiburg en pacientes con inmunodeficiencia común variable.

Introduction: Up to 25% of patients with common variable immunodeficiency (CVID) debut with autoimmunity, which is related to the Freiburg classification, which is based on flow cytometry. Objective: to determine the frequency and type of autoimmune diseases and their association with the Freiburg classification in adults with CVID. Methods: A cross-sectional, analytical and observational study was carried out with 33 patients belonging to the Primary Immunodeficiency Clinic of a third level hospital, with a diagnosis of CVID. They were divided into 3 phenotypes according to the Freiburg classification. Results: Of the 33 patients studied, 66.6% presented autoimmune diseases, 19 of them (86.3%) had cytopenia; 42.1% belonged to Freiburg group Ia, 36.8% to Ib and 21% to phenotype II. In 36.6% of the patients, autoimmune cytopenia were the first manifestation of CVID; and up to 70% of them belong to the Freiburg phenotype Ia (p = 0.086). Patients with autoimmune cytopenia had a lower percentage of isotype-switched memory B cells (p = 0.018), no higher percentage of CD21low B cells (p = 0.226). Conclusions: Classification by CVID phenotypes allows the identification of the patient's profile according to the percentage of memory B cells with isotype change, which is useful to intentionally search for non-infectious complications of the disease.

Introducción: hasta el 25% de los pacientes con inmunodeficiencia común variable (IDCV) debutan con autoinmunidad, la cual guarda relación con la clasificación de Freiburg, que se basa en la citometría de flujo. Objetivo: determinar la frecuencia y tipo de enfermedades autoinmunes y su asociación con la clasificación de Freiburg en adultos con IDCV. Métodos: se realizó un estudio transversal, analítico y observacional con 33 pacientes pertenecientes a la Clínica de Inmunodeficiencias Primarias de un hospital de tercer nivel con diagnóstico de IDCV. Se dividieron en tres fenotipos según la clasificación de Freiburg. Resultados: de los 33 pacientes estudiados, el 66.6% presentó enfermedades autoinmunes, de ellos 19 (86.3%) tuvieron citopenias. El 42.1% se clasificó en el grupo Ia de Freiburg, el 36.8% en el grupo Ib y el 21% en el fenotipo II. En el 36.6% de los pacientes las citopenias autoinmunes fueron la primera manifestación de IDCV, y hasta el 70% de ellos pertenecen al fenotipo Ia de Freiburg (p = 0.086). Los pacientes con citopenias autoinmunes tuvieron un menor porcentaje de células B de memoria con cambio de isotipo (p = 0.018), sin mayor porcentaje de células B CD21low (p = 0.226). Conclusiones: la clasificación por fenotipos en IDCV permite identificar el perfil del paciente y el tipo de manifestaciones asociadas, lo que es útil para buscar de manera intencionada complicaciones no infecciosas propias de la enfermedad.

Case report: De novo SAMD9L truncation causes neonatal-onset autoinflammatory syndrome which was successfully treated with hematopoietic stem cell transplantation.

During recent years, the identification of monogenic mutations that cause sterile inflammation has expanded the spectrum of autoinflammatory diseases, clinical disorders characterized by uncontrolled systemic and organ-specific inflammation that, in some cases, can mirror infectious conditions. Early studies support the concept of innate immune dysregulation with a predominance of myeloid effector cell dysregulation, particularly neutrophils and macrophages, in causing tissue inflammation. However, recent discoveries have shown a complex overlap of features of autoinflammation and/or immunodeficiency contributing to severe disease phenotypes. Here, we describe the first Argentine patient with a newly described frameshift mutation in SAMD9L c.2666delT/p.F889Sfs*2 presenting with a complex phenotypic overlap of CANDLE-like features and severe infection-induced cytopenia and immunodeficiency. The patient underwent a fully matched unrelated HSCT and has since been in inflammatory remission 5 years post-HSCT.

Enfermedades autoinmunes asociadas a inmunodeficiencias primarias / Autoimmune diseases associated with primary immunodeficiencies

Introducción: Las enfermedades y manifestaciones autoinmunes ocupan el segundo lugar de las enfermedades por inmunodeficiencia primaria, después de las infecciones. Objetivo: Determinar el comportamiento de las enfermedades autoinmunes en los pacientes con inmunodeficiencias primarias. Métodos: Se realizó estudio de caso control en el servicio de Alergia e Inmunología de Bayamo, Granma entre los años 2013 y 2022. El grupo de estudio fue de 38 pacientes con diagnóstico de inmunodeficiencia primaria y el grupo control de 76 pacientes sin compromiso del sistema inmune. Se empleó el programa estadístico SPSS 25, las frecuencias absolutas y relativas, odds ratio y Chi cuadrado. Resultados: Las manifestaciones sugerentes de autoinmunidad en los pacientes con inmunodeficiencias primarias fue 39,47 % y en los controles 3,95 %, OR = 15,869 y p= 0,000. Las más frecuentes fueron: dolor monoarticular en 6 pacientes (33,33 %); poliartralgia, dermatitis y alopecia en 3 casos (16,67 %) cada uno; dolor en la columna vertebral y nódulos subcutáneos, un paciente (5,56 %) cada uno. Las enfermedades autoinmunes asociadas a inmunodeficiencias primarias fueron: enfermedad celiaca (30,71 %), vitíligo (23,07 %), fibromialgia (15,38 %), eritema nodoso, la gastritis eosinofílica, anemia perniciosa y vasculitis con 7,69 % cada uno. Conclusiones: Las manifestaciones y enfermedades autoinmunes prevalecieron en pacientes con inmunodeficiencias primarias; en ambos casos fueron más frecuentes en los pacientes mayores de 18 años de edad. Las inmunodeficiencias más frecuentemente asociadas a los trastornos autoinmunes fueron las deficiencias predominantemente de anticuerpos y los defectos desregulatorios.

Introduction: Autoimmune diseases are in second place, after infections to suspect primary immunodeficiency diseases. Objective: To determine the behavior of autoimmune diseases in patients with primary immunodeficiencies. Methods: A case control study was carried out in the allergy and immunology service of Bayamo, Granma between 2013 and 2022. The universe was studied as a whole, the study group with 38 patients diagnosed with primary immunodeficiency and the control group with 76 patients without immune system compromise. The SPSS 25 statistical program, absolute and relative frequencies, odds ratio and chi-square were used. Results: The manifestations suggestive of autoimmunity in patients with PID was 39.47% and in controls 3.95%, OR = 15.869 and p = 0.000 and the most frequent were: monoarticular pain in 6 patients (33.33%), polyarthralgia, dermatitis and alopecia with 3 cases (16.67%) each one, pain in dorsal spine and subcutaneous nodule, one patient (5.56%) each one. Immune diseases associated with PID were: celiac disease (30.71%), vitiligo (23.07%), fibromyalgia (15.38%), erythema nodosum, eosinophilic gastritis, pernicious anemia and vasculitis with 7.69% each. Conclusions: Autoimmune manifestations and diseases prevailed in patients with PID, in both cases were more frequent in patients older than 18 years. The immunodeficiencies most frequently associated with autoimmune disorders were those of antibodies and those with some dysregulation component.

Neutropenia congénita. Presentación de un caso / https://revhematologia.sld.cu/index.php/hih/article/view/1695/1412

Introducción: Las inmunodeficiencias primarias son enfermedades de origen genético causadas por alteraciones cuantitativas o funcionales del sistema inmune. La incidencia de las neutropenias es de 3,4 casos por millón de personas por año Son enfermedadess heterogéneas en cuanto a la etiología, la fisiopatología, la clínica y la respuesta al tratamiento. Muchos casos presentan manifestaciones graves y mal pronóstico aún con diagnóstico y tratamiento oportunos. Objetivo: Presentar a la comunidad científico-médica un caso de neutropenia congénita con evolución desfavorable. Presentación de caso: Lactante femenina de siete meses con antecedentes de múltiples ingresos por infecciones respiratorias altas y bajas complicadas, asociadas a cuadros diarreicos, infecciones de piel y partes blandas (abscesos en región glútea y pabellones auriculares). Valorada por las especialidades de Inmunología y Hematología, las que diagnosticaron una neutropenia congénita (infecciones por Estafilococo aureus, Pseudomona sp y Cándida albicans). Recuento absoluto de neutrófilos en varias ocasiones con valores en 108 mm3; ausencia de elementos del gránulo en sistema granulopoyético en medulograma y estudios inmunológicos (ausencia de área tímica e IgA en 0,14 g/L). Se inició tratamiento con antimicrobianos de amplio espectro, inmunomoduladores (Hebertrans, Leukocin, Prednisona) y concentrado de granulocitos de donación paterna con escasa respuesta al tratamiento. Evolucionó desfavorablemente y falleció por shock séptico. El informe de necropsia confirmó el diagnóstico. Conclusiones: La neutropenia congénita se sospecha en pacientes con antecedentes de infecciones recurrentes con evolución tórpida y valores disminuidos de neutrófilos, es de gran importancia establecer un diagnóstico de certeza y conducta terapéutica temprana que favorezcan la disminución de la morbilidad y mortalidad(AU)

Introduction: Primary immunodeficiencies are diseases of genetic origin caused by quantitative and/or functional alterations of the immune system. The incidence of neutropenia is 3.4 cases per million people per year; it is a heterogeneous entity in terms of etiology, pathophysiology, clinic and response to treatment. It presents with severe manifestations and poor prognosis even with timely diagnosis and treatment. Objective: To present to scientific and medical community a case of Congenital Neutropenia with unfavorable evolution. Case presentation: Seven-month-old female infant with a history of multiple admissions for complicated upper and lower respiratory tract infections, associated with diarrhea and skin and soft tissue infections (abscesses in the gluteal region and ear pinnae). He was evaluated by Immunology and Hematology and Congenital Neutropenia was diagnosed (Staphylococcus aureus, Pseudomonas sp and Candida albicans infections), absolute neutrophil count on several occasions with values in 108 mm3, absence of granule elements in granulopoietic system in medullogram and studies immunological (absence of thymic area and IgA at 0.14 g/L). Treatment was started with broad-spectrum antimicrobials, immunomodulators (Hebertrans, Leukocin, Prednisone) and paternally donated granulocyte concentrate with little response to treatment. He evolved unfavorably and died of septic shock. The autopsy report confirmed the diagnosis. Conclusions: Congenital Neutropenia is suspected in patients with a history of recurrent infections with torpid evolution and neuthopenia, it is of great importance to establish an accurate diagnosis and early therapeutic behavior that favor the reduction of morbidity and mortality(AU)

B Cell Subsets in Colombian Adults with Predominantly Antibody Deficiencies, Bronchiectasis or Recurrent Pneumonia.

AIM: To evaluate and describe lymphocyte populations' and B cell subsets' frequencies in patients presenting with Predominantly antibody deficiencies (PAD) and diagnosed with bronchiectasis or recurrent pneumonia seen in Cali (Colombian Southwest region). MATERIALS AND METHODS: 16 subjects with PAD, 20 subjects with pulmonary complications (bronchiectasis or recurrent pneumonia) and 20 healthy donors (HD). Controls and probands between 14 and 64 years old, regardless of gender were included. Lymphocyte populations (T, B and NK cells) and B cell subsets were evaluated in peripheral blood mononuclear cells using flow cytometry, T/B/NK reagent and the pre-germinal center antibody panel proposed by the EUROflow consortium were used. EUROclass and the classification proposed by Driessen et al. were implemented. RESULTS: CVID patients exhibited increase absolute numbers of CD8+ T cells and reduce NK cells as compare with HD, other PAD cases or pulmonary complications. PAD B cell subsets were disturbed when compared to the age range-matched healthy donors. Among B cell subsets, the memory B cell compartment was the most affected, especially switched memory B cells. Four participants were classified as B- and two CVID as smB-Trnorm and smB-21low groups according to EUROclass classification. The most frequent patterns proposed by Driessen et al. were B cell production and germinal center defect. CONCLUSIONS: B cell subsets, especially memory B cells, are disturbed in PAD patients from Southwestern Colombia. To the best of our knowledge this is the most comprehensive study of B cell subsets in Colombian adults.

Gammaglobulina subcutánea: Revisión sistemática / Subcutaneous gamma globulin: A systematic review

Las inmunodeficiencias primarias constituyen enfermedades determinadas genéticamente, caracterizadas por la alteración cuantitativa y/o funcional de distintos mecanismos implicados en la respuesta inmunitaria. Algunas de ellas se caracterizan por una alteración en la producción de anticuerpos, por lo que algunos pacientes se benefician con la administración supletoria de gammaglobulina, la cual se administra mayormente por vía endovenosa, siendo la vía subcutánea una alternativa terapéutica. La siguiente revisión sistemática tiene por objetivo determinar si la gammaglobulina subcutánea tiene alguna ventaja frente al clásico uso de gammaglobulina endovenosa, en pacientes pediátricos con inmunodeficiencias primarias, revisando la bibliografía disponible hasta la actualidad (AU)

Primary immunodeficiencies are genetically determined diseases characterized by the quantitative and/or functional alteration of different mechanisms involved in the immune response. Some of these diseases are characterized by an alteration in the antibody production and therefore some patients benefit from the supplementary administration of gamma globulin, which is mostly administered intravenously, with the subcutaneous route being a therapeutic alternative. The following systematic literature review aims to determine whether subcutaneous gamma globulin has any advantage over the classic use of intravenous gamma globulin in pediatric patients with primary immunodeficiencies (AU)

Inborn Errors of Immunity With Fetal or Perinatal Clinical Manifestations.

In this article we revised the literature on Inborn Errors of Immunity (IEI) keeping our focus on those diseases presenting with intrauterine or perinatal clinical manifestations. We opted to describe our findings according to the IEI categories established by the International Union of Immunological Societies, predominantly addressing the immunological features of each condition or group of diseases. The main finding is that such precocious manifestations are largely concentrated in the group of primary immune regulatory disorders (PIRDs) and not in the group of classical immunodeficiencies. The IEI categories with higher number of immunological manifestations in utero or in perinatal period are: (i) diseases of immune dysregulation (HLH, IPEX and other Tregopathies, autosomal recessive ALPS with complete lack of FAS protein expression) and (ii) autoinflammatory diseases (NOMID/CINCA, DIRA and some interferonopathies, such as Aicardi-Goutières syndrome, AGS, and USP18 deficiency). Regarding the other IEI categories, some patients with Omenn syndrome (an atypical form of SCID), and a few X-linked CGD patients present with clinical manifestations at birth associated to immune dysregulation. The most frequent clinical features were hydrops fetalis, intrauterine growth retardation leading to fetal loss, stillbirths, and prematurity, as in HLH and IPEX. Additionally, pseudo-TORCH syndrome was observed in AGS and in USP18 deficiency. The main goal of our review was to contribute to increasing the medical awareness of IEI with intrauterine and perinatal onset, which has obvious implications for diagnosis, treatment, and genetic counseling.

Inmunodeficiencia combinada grave: Presentación de un caso / Severe Combined Immunodeficiency: Case presentation

Introducción: Las inmunodeficiencias primarias son un grupo heterogéneo de trastornos hereditarios ocasionados por defectos del desarrollo o función del sistema inmunológico. Las inmunodeficiencias combinadas graves constituyen el 15 por ciento de las inmunodeficiencias primarias, son graves y los pacientes rara vez sobreviven sin tratamiento después del primer año de vida, lo que obliga a un diagnóstico y tratamiento oportuno. Objetivo: Presentar un caso con inmunodeficiencia combinada grave, condición reportada con poca frecuencia y evolución desfavorable. Presentación de caso: Lactante masculino de seis meses con antecedentes de cuatro ingresos en Unidad de Terapia Intensiva por infecciones, el último por bronconeumonía bilateral. Fue valorado por Inmunología y se diagnosticó una inmunodeficiencia combinada grave por la clínica (infecciones por gérmenes oportunistas: Candida albicans y Pneumocistys jirovecii) y estudios inmunológicos (con disminución de los anticuerpos IgG: 0,02 g/L, IgM: 0.1 g/L e IgA: 0 g/L), subpoblaciones linfocitarias disminuidas (CD3/CD4: 9,3 por ciento, CD3/CD8: 5,6 por ciento, CD19: 0 por ciento, CD 16: 0,73 por ciento), además hipoplasia tímica severa (120 mm2). Se inició tratamiento con antimicrobianos de amplio espectro e inmunoestimulantes (Hebertrans y Biomodulina T). Evolucionó desfavorablemente y falleció por shock séptico. Conclusiones: La inmunodeficiencia combinada grave es una emergencia pediátrica que debe tenerse en cuenta en pacientes con antecedentes de infecciones recurrentes, es vital conocer las manifestaciones clínicas tempranas que permitan la sospecha diagnóstica, haciendo uso de todas las herramientas disponibles para su confirmación. El diagnóstico precoz es el elemento clave para la reducción de la morbilidad y mortalidad relacionada con estas enfermedades(AU)

Introduction: Primary Immunodeficiencies are a heterogeneous group of inherited disorders caused by defects in development or function of the immune system. Severe Combined Immunodeficiencies constitute 15% of the primary immunodeficiencies, they are acute and patients rarely survive without treatment after the first year of life, requiring a quick diagnosis and treatment. Objective: To present a case on Severe Combined Immunodeficiency, a condition infrequently reported and with unfavorable evolution. Case presentation: Six-month-old male infant with a history of four admissions to the Intensive Care Unit due to infections, in the latter one due to bilateral bronchopneumonia. He was evaluated by Immunology and a Severe Combined Immunodeficiency was diagnosed by the clinic (infections by opportunistic germs: Candida albicans and Pneumocistys jirovecii) and immunological studies (with a decrease in IgG antibodies: 0.02 g/L, IgM: 0.1 g/L and IgA: 0 g/L), decreased lymphocyte subpopulations (CD3/CD4: 9.3 percent, CD3/CD8: 5.6 percent, CD19: 0 percent, CD 16: 0.73 percent), in addition to severe thymic hypoplasia (120 mm2). Treatment with broad spectrum antimicrobials and immunostimulants (Hebertrans and Biomodulin T) was started. He evolved unfavorably and died of septic shock. Conclusions: Severe Combined Immunodeficiency is a pediatric emergency that must be taken into account in patients with a history of recurrent infections, it is vital to know the early clinical manifestations that allow a suspected diagnosis, making use of all the available tools for its confirmation. Early diagnosis is the key element in reducing morbidity and mortality related to these diseases(AU)

A Critical Review on the Standardization and Quality Assessment of Nonfunctional Laboratory Tests Frequently Used to Identify Inborn Errors of Immunity.

Inborn errors of immunity (IEI), which were previously termed primary immunodeficiency diseases, represent a large and growing heterogeneous group of diseases that are mostly monogenic. In addition to increased susceptibility to infections, other clinical phenotypes have recently been associated with IEI, such as autoimmune disorders, severe allergies, autoinflammatory disorders, benign lymphoproliferative diseases, and malignant manifestations. The IUIS 2019 classification comprises 430 distinct defects that, although rare individually, represent a group affecting a significant number of patients, with an overall prevalence of 1:1,200-2,000 in the general population. Early IEI diagnosis is critical for appropriate therapy and genetic counseling, however, this process is deeply dependent on accurate laboratory tests. Despite the striking importance of laboratory data for clinical immunologists, several IEI-relevant immunoassays still lack standardization, including standardized protocols, reference materials, and external quality assessment programs. Moreover, well-established reference values mostly remain to be determined, especially for early ages, when the most severe conditions manifest and diagnosis is critical for patient survival. In this article, we intend to approach the issue of standardization and quality control of the nonfunctional diagnostic tests used for IEI, focusing on those frequently utilized in clinical practice. Herein, we will focus on discussing the issues of nonfunctional immunoassays (flow cytometry, enzyme-linked immunosorbent assays, and turbidimetry/nephelometry, among others), as defined by the pure quantification of proteins or cell subsets without cell activation or cell culture-based methods.

Clinical Manifestations, Mutational Analysis, and Immunological Phenotype in Patients with RAG1/2 Mutations: First Cases Series from Mexico and Description of Two Novel Mutations.

Mutations in recombinase activating genes 1 and 2 (RAG1/2) result in human severe combined immunodeficiency (SCID). The products of these genes are essential for V(D)J rearrangement of the antigen receptors during lymphocyte development. Mutations resulting in null-recombination activity in RAG1 or RAG2 are associated with the most severe clinical and immunological phenotypes, whereas patients with hypomorphic mutations may develop leaky SCID, including Omenn syndrome (OS). A group of previously unrecognized clinical phenotypes associated with granulomata and/or autoimmunity have been described as a consequence of hypomorphic mutations. Here, we present six patients from unrelated families with missense variants in RAG1 or RAG2. Phenotypes observed in these patients ranged from OS to severe mycobacterial infections and granulomatous disease. Moreover, we report the first evidence of two variants that had not been associated with immunodeficiency. This study represents the first case series of RAG1- or RAG2-deficient patients from Mexico and Latin America.

Inmunodeficiencia Combinada Severa, reporte de pacientes chilenos diagnosticados durante el período 1999-2020 / Severe combined immunodeficiency, report of Chilean patients diagnosed during the 1999-2020 period

INTRODUCCIÓN: La inmunodeficiencia combinada severa (IDCS) corresponde a una de las formas más graves de inmunodeficiencia primaria, existiendo escasos datos nacionales sobre ésta. OBJETIVO: describir la epidemiología, complicaciones, pronóstico y uso de la vacuna BCG en pacientes chilenos con IDCS. PACIENTES Y MÉTODO: Estudio retrospectivo de pacientes diagnosticados con IDCS entre los años 1999 y 2020 por médicos inmunólogos a lo largo de Chile. El diagnóstico de IDCS se realizó conforme a los criterios propuestos por Shearer: linfocitos T (CD3+) < 300 células/μL y prolife ración 10% del límite de normalidad en respuesta a fitohemaglutinina o presencia de linfocitos T de origen materno. Se obtuvieron de la ficha clínica los datos correspondientes a: sexo, edad al diagnóstico, consanguinidad, región de origen, subpoblaciones linfocitarias, diagnóstico genético, complicaciones infecciosas y no infecciosas, vacunación BCG y sus complicaciones, edad de deriva ción al centro de TPH y causa de mortalidad no relacionada al TPH. RESULTADOS: se diagnosticaron 25 casos de IDCS en 22 familias entre los años 1999-2020. 78% varones, la edad media a la primera manifestación fue 2.3 meses (0-7), mientras que la edad media al diagnóstico fue de 3.4 meses (0 7). Un 16% de los casos tenía un antecedente familiar de IDCS. Un 40% de los casos fueron diag nosticados en la Región Metropolitana. El inmunofenotipo más frecuente fue T-B-NK+ (48%). Se realizaron estudios genéticos en 69,5% de los casos, siendo los defectos genéticos en RAG2 (39%) la causa más frecuente. Un 88% de los casos recibió la vacuna Bacillus Calmette-Guerin (BCG) previo al diagnóstico, incluidos 2 pacientes con historia familiar positiva, 36% de los vacunados experimentó complicaciones de la BCG. La edad media a la derivación a trasplante fue de 7,4 meses (5-16). De los 25 pacientes, 11 fallecieron previo a la derivación a un centro de trasplante. CONCLUSIÓN: En Chile existe un retraso clínicamente significativo entre las primeras manifestaciones y el diagnóstico de IDCS, así como un importante retraso en la derivación a centros de trasplante. La mayoría de los pacientes con IDCS reciben la vacuna BCG, pese a tener antecedentes familiares, y experimentan frecuentemente complicaciones de la vacuna.

INTRODUCTION: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency. To date, there is little local information about this disease. OBJECTIVE: To describe the epidemiology, complications, prognosis, and use of the BCG vaccine in Chilean patients with SCID. PATIENTS AND METHOD: Retrospective review of the clinical records of patients diagnosed with SCID by clinical immunologists between 1999 and 2020 throughout Chile. SCID was diagnosed according to the cri teria proposed by Shearer: T lymphocytes (CD3+) < 300 cells/μL and proliferation 10% of the limit of normality in response to phytohemagglutinin or presence of T lymphocytes of maternal origin. Data collected from the clinical records were: sex, age at diagnosis, consanguinity, region of origin, lymphocyte subpopulations, genetic diagnosis, infectious and non-infectious complications, BCG vaccination and its complications, age at referral to the bone marrow transplant (BMT) center, and cause of non-BMT-related mortality. RESULTS: Between 1999 and 2020, 25 patients were diagnosed with SCID. 78% of them were male, mean age at first manifestation of the disease was 2.3 months (0-7), while the mean age at diagnosis was 3.4 months (0-7). 16% of patients had a family history of SCID. 40% of cases were diagnosed within the Metropolitan Region. The most frequent immuno- phenotype was T-B-NK+ SCID (48%). Genetic studies were done in 69.5% of cases, mutations in the RAG2 gene were the most common etiology of SCID (39%). 88% of SCID patients received the Bacillus Calmette-Guerin (BCG) vaccine before diagnosis, including 2 cases with a known family history of SCID. 36% of those who received the vaccine had BCG-related complications. The mean age at referral to a bone marrow transplant center was 7.4 months (5-16). 11/25 patients died before being transferred to a transplant center. DISCUSSION: There is a clinically significant delay between the first manifestations and the diagnosis of SCID in Chilean patients, as well as an important time gap between the diagnosis of SCID and referral to a center for BMT. Most SCID cases in Chile receive the BCG vaccine, despite a known family history of the disease, and frequently develop vaccine-related complications.

Immune Monitoring of Patients With Primary Immune Regulation Disorders Unravels Higher Frequencies of Follicular T Cells With Different Profiles That Associate With Alterations in B Cell Subsets.

Primary immune regulation disorders lead to autoimmunity, allergy and inflammatory conditions due to defects in the immune homeostasis affecting different T, B and NK cell subsets. To improve our understanding of these conditions, in this work we analyzed the T and B cell compartments of 15 PID patients with dysregulation, including 3 patients with STAT1 GOF mutation, 7 patients with CVID with dysregulation, 3 patients with mutations in CTLA4, 1 patient with CD25 mutation and 1 patient with STAT5b mutation and compared them with healthy donors and with CVID patients without dysregulation. CD4+ and CD8+ T cells from the patients exhibited a significant decreased frequency of naïve and regulatory T cells with increased frequencies of activated cells, central memory CD4+ T cells, effector memory CD8+ T cells and terminal effector CD8+ T cells. Patients also exhibited a significantly increased frequency of circulating CD4+ follicular helper T cells, with altered frequencies of cTfh cell subsets. Such cTfh cells were skewed toward cTfh1 cells in STAT1 GOF, CTLA4, and CVID patients, while the STAT5b deficient patient presented a skew toward cTfh17 cells. These alterations confirmed the existence of an imbalance in the cTfh1/cTfh17 ratio in these diseases. In addition, we unraveled a marked dysregulation in the B cell compartment, characterized by a prevalence of transitional and naïve B cells in STAT1 GOF and CVID patients, and of switched-memory B cells and plasmablast cells in the STAT5b deficient patient. Moreover, we observed a significant positive correlation between the frequencies cTfh17 cells and switched-memory B cells and between the frequency of switched-memory B cells and the serum IgG. Therefore, primary immunodeficiencies with dysregulation are characterized by a skew toward an activated/memory phenotype within the CD4+ and CD8+ T cell compartment, accompanied by abnormal frequencies of Tregs, cTfh, and their cTfh1 and cTfh17 subsets that likely impact on B cell help for antibody production, which likely contributes to their autoimmune and inflammatory conditions. Therefore, assessment of these alterations by flow cytometry constitutes a simple and straightforward manner to improve diagnosis of these complex clinical entities that may impact early diagnosis and patients' treatment. Also, our findings unravel phenotypic alterations that might be associated, at least in part, with some of the clinical manifestations observed in these patients.

Primary Immunodeficiencies in a Mesoregion of São Paulo, Brazil: Epidemiologic, Clinical, and Geospatial Approach.

Background: Primary immunodeficiencies (PIDs) are rare genetic disorders leading to immunologic abnormalities that can affect different organs and systems. We determined the epidemiology, clinical, and geospatial characteristics of PID disorders among patients diagnosed over a 5 year period in a reference hospital covering a mesoregion in São Paulo, Brazil. Methods: A retrospective analysis of 39 patients with recognizable PIDs according to the criteria of the European Society of Primary Immunodeficiencies were enrolled. Thirty-four patients came from outpatient immunodeficiency clinics and five patients from active search. Demographic, clinical, and immunologic data were collected, and maps were constructed using a geographic information system. Results: The ratio of females to males was 1.4:1, and 48.7% of patients were younger than 17 years of age. The mean age at the onset of symptoms in children was 2.0 years [standard error of the mean (SEM), 1.7 years] and the diagnosis lag was 5.1 years (SEM, 3.1 years); the mean age at diagnosis in adults was 16.3 years (SEM, 11.8 years) and the lag was 10.8 years (SEM, 10.9 years). Antibody deficiency and common variable immunodeficiencies were the most common categories and phenotypes, respectively. The need for intravenous antibiotics and respiratory tract infections were the most prevalent warning signs, with an overall mortality rate of 15.3%. Autoimmune diseases were diagnosed in 56.4% and visceral leishmaniasis in 5.1% of patients. In the active search, 29 patients were investigated and 17.2% were diagnosed; early diagnosis, the involvement of multidisciplinary professionals, and dissemination of knowledge achieved milestone benefits. The distribution of PID networks in Brazil shows great asymmetry between regions and at a regional level; it was shown that the patients lived mainly in Presidente Prudente municipality. Conclusions: The implementation of an immunodeficiency outpatient clinic in a referral hospital covering a mesoregion with a large population has led to the generation of policies and practices to improve the diagnosis, quality of life, and care of patients with PIDs and their families. Furthermore, the search for hospitalized patients with warning signs for PIDs showed great benefits. Inequality in the distribution of PID network centers in Brazil was demonstrated.

Systemic BK Virus Infection in a Pediatric Patient With Severe Combined Immunodeficiency.

Human BK virus (BKV) infection is known to occur mostly during childhood with the establishment of latent infection with no tissue damage or clinical manifestations. However, conditions causing immunosuppression can lead to increased virus replication and tissue damage. Although the tissues most commonly involved are the kidneys, bladder, ureters and, to some extent, brain tissue, there are some reports that suggest that BKV may cause multisystemic infections. In this case, a 12-month-old child was seen to suffer from multiple gastrointestinal infections. This prompted a search for immunodeficiencies, which revealed the presence of severe combined immunodeficiency. The child was eventually hospitalized and continued showing recurrent bouts of gastroenteritis as well as lower respiratory infection. After multiple antibiotic courses, he developed acute kidney injury, a hemophagocytic syndrome, and eventually respiratory failure, which led to his death a year later. Autopsy findings revealed the presence of a disseminated BKV infection involving the kidneys, ureters, leptomeninges, and pancreas. Analysis of the literature failed to show any previous case of BKV pancreatitis. The present case suggests that BKV can damage more tissues than previously reported and may be responsible for systemic infections in immunosuppressed patients.

[Registry of Inborn errors of immunity in a pediatric hospital]. / Registro de errores innatos de la inmunidad en un hospital pediátrico.

In 2017, the Pediatric Hospital of Sinaloa (PHS) began its affiliation to the registry of patients with primary immunodeficiency or inborn errors of immunity (IEI) on the platform of the Latin American Society for Immunodeficiencies (LASID). During this period, twelve cases with IEI have been diagnosed and treated at the hospital. The age category at the time of diagnosis varied from two days to sixteen years old, and the range of the onset of the symptoms varied from nineteen days to four years, with a predominance of males (67%). The most frequent IEI was predominantly antibody deficiency (33.3%), followed by defects in the number or function of phagocytes (16.6%), autoinflammatory disorders (16.6%), immunodeficiencies that affect cellular and humoral immunity (16.6%), combined immunodeficiencies associated with syndromic findings (8.3%), and defects in intrinsic and inborn immunity (8.3%). 84% of patients received intravenous immunoglobulin and, in one case of a patient with Wiskott-Aldrich syndrome, a pathogenic variant in the WAS gene was identified; a patient received hematopoietic stem cell transplantation, 33.3% of patients died, of which 25% died of sepsis and 8.3% died of massive hemorrhage. The registry of IEI provides information about epidemiological data, incidences, prevalence, diagnoses, and treatments, which will favor the development of new health policies for obtaining resources and tools to improve the care models.

El Hospital Pediátrico de Sinaloa (HPS) inició el registro de pacientes con inmunodeficiencia primaria o error innato de la inmunidad (EII) en la plataforma de la Sociedad Latinoamericana de Inmunodeficiencias Primarias (LASID) desde 2017. Durante ese periodo se han diagnosticado y tratado 12 casos en el hospital. El rango de edad al momento del diagnóstico fue de dos días a 16 años y el rango de inicio de los síntomas de 19 días a cuatro años, con predominio del sexo masculino (67 %). El EII más frecuente fue la deficiencia predominantemente de anticuerpos (33.3 %), seguida de defectos en fagocitos en número o función (16.6 %), desórdenes autoinflamatorios (16.6 %), inmunodeficiencias que afectan la inmunidad celular y humoral (16.6 %), inmunodeficiencias combinadas asociadas con los hallazgos sindromáticos (8.3 %) y defectos en la inmunidad intrínseca e innata (8.3 %). El 84 % recibió inmunoglobulina intravenosa; se identificó la variante patogénica en el gen WAS en un caso con síndrome de Wiskott-Aldrich; un paciente recibió trasplante de células progenitoras hematopoyética; 33.3 % falleció, 25 % por sepsis y 8.3 % por hemorragia masiva. El registro de las EII permite conocer datos epidemiológicos, incidencia, prevalencia, diagnósticos y tratamientos, lo que favorecerá al desarrollo de nuevas políticas sanitarias para la obtención de recursos y herramientas para mejorar los modelos de atención.

Inmunodeficiencias primarias y citopenias / Primary immunodeficiencies and cytopenias

Introducción: La visión actual de las enfermedades por inmunodeficiencia primaria (IDP) incluye un número creciente de síndromes que están asociados con la desregulación inmune y la autoinmunidad como características predominantes. Las citopenias autoinmunes pueden ser el primer signo de desregulación que precede a la presentación clásica de inmunodeficiencia primaria, con infecciones recurrentes u oportunistas. El conocimiento de un espectro de enfermedades potencialmente involucradas (hematológicas, reumatológicas e inmunológicas) es crucial para la identificación de una cierta proporción de genotipos y fenotipos de otros diagnósticos descritos. También permitirá excluir desórdenes como lupus eritematoso sistémico, inmunodeficiencia variable común, síndrome linfoproliferativo autoinmune; así como realizar diagnósticos diferenciales noveles como la deficiencia de GATA2, deficiencia de CD27, deficiencia de sensibilidad a lipopolisacáridos, síndrome fosfoinositol-3-quinasa delta activada, inmunodeficiencia ligada a X con déficit de magnesio y otros. Objetivo: Proporcionar una sinopsis conceptual de la aparición de citopenias en las IDP con el propósito de actualizar el conocimiento actual sobre dicho tema y de aumentar la percepción, tanto de hematólogos como inmunólogos, en relación a la presentación de citopenias como manifestación de estas enfermedades. Métodos: Se revisaron artículos originales y de corte experimental publicados en la década 2009 - 2019, en algunas bases de datos de la Biblioteca Virtual de Salud (BVS) de Cuba. Conclusiones: Al igual que las formas benignas autolimitadas de citopenia autoimmune post o parainfecciosas, o la neutropenia autoimmune adquirida de la infancia, que generalmente ocurren independientemente de una IDP subyacente reconocida, muchas de las citopenias que acompañan a esta enfermedad (pero no todas) están mediadas por autoanticuerpos. Es esencial entonces, que los médicos valoren, ante la evidencia clara de citopenia, que esta puede ser autoinmune(AU)

Introduction: The current view of primary immunodeficiency diseases (IDP) includes an increasing number of syndromes that are associated with immune dysregulation and autoimmunity as predominant characteristics. Autoimmune cytopenias may be the first sign of dysregulation that precedes the classic presentation of primary immunodeficiency, with recurrent or opportunistic infections. The knowledge of a spectrum of potentially involved diseases (hematological, rheumatological and immunological) is crucial for the identification of a certain proportion of genotypes and phenotypes of other diagnoses described. It will also allow excluding disorders such as systemic lupus erythematosus, common variable immunodeficiency, autoimmune lymphoproliferative syndrome; as well as making novel differential diagnoses such as GATA2 deficiency, CD27 deficiency, lipopolysaccharide sensitivity deficiency, activated delta phosphoinositol-3-kinase syndrome, X-linked immunodeficiency with magnesium deficiency and others. Objective: This review provides a conceptual synopsis of the appearance of cytopenias in the IDPs with the purpose of updating current knowledge on this topic and increasing the perception, of both hematologists and immunologists, in relation to the presentation of cytopenias as manifestation of these diseases. Methodos: Original and experimental articles published in the 2009-2019 decade were reviewed in some databases of the Virtual Health Library (VHL) of Cuba. Conclusions: As the self-limited benign forms of post or parainfectious autoimmune cytopenia, or childhood acquired autoimmune neutropenia, which generally occur independently of a recognized underlying IDP, many of the cytopenias that accompany this disease (but not all) mediated by autoantibodies. It is essential, then, that doctors assess, given the clear evidence of cytopenia, that it may be autoimmune(AU)

Vacunación BCG e inmunodeficiencias primarias: ¿es momento de un cambio? / BCG vaccine administration schedule and primary immunodeficiencies: Is it time for a change?

Resumen: Los pacientes con Inmunodeficiencias primarias (IDP) tienen un riesgo elevado de complicaciones severas por la vacuna BCG, incluso mortalidad. Es necesario evaluar periódicamente el riesgo versus beneficio de la vacunación universal BCG en el periodo neonatal. Chile es un país con baja incidencia de tuberculosis (TB) pero cuya epidemiología ha cambiado recientemente con un aumento de los casos. Cambios en esquemas de vacunación BCG en países con incidencias mayores o similares de TB y con coberturas de vacunación menores han sido posibles sin aumento de los casos graves de TB que son los que previene la BCG. El cambio ha evitado complicaciones graves en pacientes con IDP. Creemos que un análisis crítico de la fecha de vacunación BCG debe realizarse hoy en Chile. Más aún dada la posibilidad técnica de realizar screening neonatal de IDP.

Abstract: Patients with Primary Immunodeficiencies (PID) are at a higher risk of developing severe morbidities and mortality due to the administration of BCG vaccine. Risk-to-benefit of universal BCG vaccina tion of newborns must be assessed periodically. Chile has a low incidence of tuberculosis (TB) but the local epidemiology has recently changed with an increase of TB cases. Changes in the BCG vaccine schedule have been made in countries with similar or higher TB incidences and lower BCG vaccine coverage, with no increase in the severe TB cases, which are prevented by BCG. These changes have prevented serious complications in PID patients. We propose a critical analysis of the BCG adminis tration date in Chile due to the technical possibility of performing neonatal PID screening.

[Chronic granulomatous disease. Update and review]. / Enfermedad granulomatosa crónica. Actualización y revisión.

Chronic granulomatous disease (CGD) is a primary immunodeficiency syndrome which is characterized by increased susceptibility to severe fungal and bacterial infections. CGD is the result of the lack of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase enzyme in the patient's phagocytes to produce superoxide. It is characterized by recurrent infections with a narrow spectrum of bacteria and fungi, as well as a common set of inflammatory complications, including inflammatory bowel disease. The most frequently found pathogens are Staphylococcus aureus, species of Aspergillus, species of Klebsiella, Burkholderia cepacia, Serratia marcescens and species of Salmonella. Long term antibiotic prophylaxis has helped fight infections associated with chronic granulomatous disease, while the steady progress in bone marrow transplants and the possibility of gene therapy are defined as permanent treatment options.

La enfermedad granulomatosa crónica es un síndrome de inmunodeficiencia primaria caracterizado por mayor susceptibilidad para desarrollar infecciones fúngicas y bacterianas graves. La enfermedad granulomatosa crónica es el resultado de una falla de la enzima nicotinamida adenina dinucleótido fosfato oxidasa en los fagocitos del paciente para producir superóxido. Se caracteriza por infecciones recurrentes con un espectro estrecho de bacterias y hongos, así como por un conjunto común de complicaciones inflamatorias, entre las que se incluye la enfermedad inflamatoria intestinal. Los patógenos más frecuentemente encontrados son Staphylococcus aureus, Aspergillus spp., Klebsiella spp., Burkholderia cepacia, Serratia marcescens y Salmonella spp. La profilaxis antibiótica a largo plazo ha ayudado a combatir las infecciones asociadas con la enfermedad granulomatosa crónica, mientras que el progreso constante en el trasplante de médula ósea y la posibilidad de la terapia génica ser perfilan como opciones de tratamiento permanente.

LRBA in the endomembrane system.

Bi-allelic mutations in LRBA (from Lipopolysaccharide-responsive and beige-like anchor protein) result in a primary immunodeficiency with clinical features ranging from hypogammaglobulinemia and lymphoproliferative syndrome to inflammatory bowel disease and heterogeneous autoimmune manifestations. LRBA deficiency has been shown to affect vesicular trafficking, autophagy and apoptosis, which may lead to alterations of several molecules and processes that play key roles for immunity. In this review, we will discuss the relationship of LRBA with the endovesicular system in the context of receptor trafficking, autophagy and apoptosis. Since these mechanisms of homeostasis are inherent to all living cells and not only limited to the immune system and also, because they are involved in physiological as well as pathological processes such as embryogenesis or tumoral transformation, we envisage advancing in the identification of potential pharmacological agents to manipulate these processes.

Las mutaciones bi-alélicas en LRBA (del inglés, Lipopolysaccharide-responsive and beige-like anchor protein) conllevan a una inmunodeficiencia primaria con características clínicas que abarcan desde hipogamaglubulinemia y síndrome linfoproliferativo hasta una enfermedad inflamatoria intestinal y manifestaciones autoinmunes heterogéneas. Se ha demostrado que la deficiencia de LRBA afecta el tráfico vesicular, la autofagia y la apoptosis pudiendo generar alteraciones en la regulación de varios procesos importantes para la inmunidad. En esta revisión discutiremos la relación de LRBA con el sistema endovesicular en el contexto del tráfico de receptores, la autofagia y la apoptosis. Estos mecanismos de homeostasis son inherentes a todas las células y no están limitados a las células del sistema inmune, están involucrados en procesos fisiológicos y patológicos, como la embriogénesis o la transformación tumoral. El entendimiento de la función de LRBA permitirá avanzar en la identificación de los posibles blancos farmacológicos para manipular estos procesos.

Transplantation of Hematopoietic Stem Cells for Primary Immunodeficiencies in Brazil: Challenges in Treating Rare Diseases in Developing Countries.

The results of hematopoietic stem cell transplant (HSCT) for primary immunodeficiency diseases (PID) have been improving over time. Unfortunately, developing countries do not experience the same results. This first report of Brazilian experience of HSCT for PID describes the development and results in the field. We included data from transplants in 221 patients, performed at 11 centers which participated in the Brazilian collaborative group, from July 1990 to December 2015. The majority of transplants were concentrated in one center (n = 123). The median age at HSCT was 22 months, and the most common diseases were severe combined immunodeficiency (SCID) (n = 67) and Wiskott-Aldrich syndrome (WAS) (n = 67). Only 15 patients received unconditioned transplants. Cumulative incidence of GVHD grades II to IV was 23%, and GVHD grades III to IV was 10%. The 5-year overall survival was 71.6%. WAS patients had better survival compared to other diseases. Most deaths (n = 53) occurred in the first year after transplantation mainly due to infection (55%) and GVHD (13%). Although transplant for PID patients in Brazil has evolved since its beginning, we still face some challenges like delayed diagnosis and referral, severe infections before transplant, a limited number of transplant centers with expertise, and resources for more advanced techniques. Measures like newborn screening for SCID may hasten the diagnosis and ameliorate patients' conditions at the moment of transplant.