Analysis of clinical phenotype and variant of RAG1 gene in a child with B-cell-negative Severe Combined Immunodeficiency / 中华医学遗传学杂志

OBJECTIVE@#To report on a child with B-cell-negative severe combined immunodeficiency (B-SCID) manifesting as fulminant myocarditis and carry out genetic testing for her.@*METHODS@#A child with B-SCID who presented at Fujian Maternity and Child Health Care Hospital on January 31, 2021 was selected as the subject. Whole exome sequencing was carried out for her. Candidate variant was verified by Sanger sequencing.@*RESULTS@#The female infant had developed recurrent skin and lung infections soon after birth, and was admitted due to fulminant myocarditis. Serological examination has disclosed a remarkable reduction in immunoglobulins. Flow cytometric analysis revealed that her peripheral blood T and B lymphocytes and NK cells were significantly reduced. Whole exome sequencing revealed that she has harbored a homozygous c.C3007T (p.Q1003X) nonsense variant of the RAG1 gene, for which both of her parents were heterozygous carriers. The variant has not been recorded in normal population databases. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was predicted to be pathogenic.@*CONCLUSION@#A case of RAG1 gene associated B-SCID has been diagnosed. Above finding has enriched the spectrum of RAG1 gene variants and enabled early diagnosis and intervention of the disease.

Inmunodeficiencia combinada severa: es tiempo de su detección precoz / Severe combined immunodeficiency: the time for newborn screening has come

Las inmunodeficiencias primarias (IDP) son un conjunto de cerca de 350 enfermedades genéticas que afectan el funcionamiento del sistema inmunológico. Los avances en diagnóstico genético han permitido describir nuevos defectos en el sistema inmune, ampliando el espectro de manifestaciones de las IDP más allá de la susceptibilidad a infecciones. Aunque la mayoría de las IDP se presentan con infecciones recurrentes u oportunistas, un subgrupo puede presentarse por el desarrollo precoz de fenómenos autoinflamatorios, tumorales y, paradojalmente, la coexistencia de autoinmunidad e inmunodeficiencia en un mismo paciente. Al igual que sus manifestaciones clínicas, la severidad de las IDP es variable. La inmunodeficiencia combinada severa (IDCS), caracterizada por una falla en la respuesta humoral y celular, es una de las formas más graves de IDP y el único tratamiento curativo disponible en Latino-América es el trasplante de precursores hematopoyéticos. La IDCS es 100% letal durante los dos primeros años de vida si no se diagnostica y trata oportunamente. Por el contrario, si se trasplantan precozmente, estos pacientes pueden alcanzar una sobrevida normal. Pese a los avan ces en el diagnóstico de IDP que se han observado en nuestro país en los últimos años, los recursos diagnósticos no se encuentran disponibles en todas las regiones, lo que dificulta el reconocimiento temprano de la IDCS y otras IDP en grandes áreas del país. El objetivo de esta actualización es revisar conceptos generales sobre la fisiopatología de la IDCS, diagnóstico, manejo inicial y plantear la nece sidad de la implementación del tamizaje neonatal de IDCS en Chile.

Primary immunodeficiencies (PIDs) are a set of about 350 genetic disorders that affect the normal function of the immune system. Advances in genetic diagnosis have allowed the description of new defects in the immune system, broadening the clinical spectrum of PIDs' manifestations beyond susceptibility to infection. Although most PIDs present with recurrent or opportunistic infections, a subgroup of them may be recognized by the early development of auto-inflammatory events, tumors and, paradoxically, the coexistence of autoimmunity and immunodeficiency in the same patient. As their clinical manifestations, the severity of PIDs is highly variable. Severe combined immunodefi ciency (SCID), a PID that affects cellular and humoral immunity, is one of the most severe forms of PIDs and the only available curative treatment in Latin America is hematopoietic stem cells trans plantation. All patients affected by SCID die during the first two years of life if they are not diagnosed and treated opportunely. In contrast, early transplantation of patients with SCID can lead to excellent survival outcomes. Despite recent advances in the diagnosis of PIDs in Chile, diagnostic resources are not available throughout the country, making the early diagnosis of SCID and other forms of PID difficult in big areas of Chile. The objective of this article is to review general concepts on the patho physiology, diagnosis, and initial management of SCID and raise the need for the implementation of neonatal screening for SCID in Chile.

TRIAGEM NEONATAL DE IMUNODEFICIÊNCIAS GRAVES COMBINADAS POR MEIO DE TRECS E KRECS: SEGUNDO ESTUDO PILOTO NO BRASIL / NEWBORN SCREENING FOR SEVERE COMBINED IMMUNODEFICIENCIES USING TRECS AND KRECS: SECOND PILOT STUDY IN BRAZIL

RESUMO Objetivo: Validar a quantificação de T-cell receptor excision circles (TRECs) e kappa-deleting recombination circles (KRECs) por reação em cadeia de polimerase (polymerase chain reaction, PCR) em tempo real (qRT-PCR), para triagem neonatal de imunodeficiências primárias que cursam com defeitos nas células T e/ou B no Brasil. Métodos: Amostras de sangue de recém-nascidos (RN) e controles foram coletadas em papel-filtro. O DNA foi extraído e os TRECs e KRECs foram quantificados por reação duplex de qRT-PCR. O valor de corte foi determinado pela análise de Receiver Operating Characteristics Curve, utilizando-se o programa Statistical Package for the Social Sciences (SSPS) (IBM®, Armonk, NY, EUA). Resultados: 6.881 amostras de RN foram analisadas quanto à concentração de TRECs e KRECs. Os valores de TRECs variaram entre 1 e 1.006 TRECs/µL, com média e mediana de 160 e 139 TRECs/µL, respectivamente. Três amostras de pacientes diagnosticados com imunodeficiência grave combinada (severe combined immunodeficiency, SCID) apresentaram valores de TRECs abaixo de 4/µL e um paciente com Síndrome de DiGeorge apresentou TRECs indetectáveis. Os valores de KRECs encontraram-se entre 10 e 1.097 KRECs/µL, com média e mediana de 130 e 108 KRECs/µL, e quatro pacientes com diagnóstico de agamaglobulinemia tiveram resultados abaixo de 4 KRECs/µL. Os valores de corte encontrados foram 15 TRECs/µL e 14 KRECs/µL, e foram estabelecidos de acordo com a análise da Receiver Operating Characteristics Curve, com sensibilidade de 100% para detecção de SCID e agamaglobulinemia, respectivamente. Conclusões: A quantificação de TRECs e KRECs foi capaz de diagnosticar crianças com linfopenias T e/ou B em nosso estudo, validando a técnica e dando o primeiro passo para a implementação da triagem neonatal em grande escala no Brasil.

ABSTRACT Objective: To validate the quantification of T-cell receptor excision circles (TRECs) and kappa-deleting recombination excision circles (KRECs) by real-time polymerase chain reaction (qRT-PCR) for newborn screening of primary immunodeficiencies with defects in T and/or B cells in Brazil. Methods: Blood samples from newborns and controls were collected on filter paper. DNA was extracted and TRECs, and KRECs were quantified by a duplex real-time PCR. The cutoff values were determined by receiver operating characteristic curve analysis using SPSS software (IBM®, Armonk, NY, USA). Results: Around 6,881 samples from newborns were collected and TRECs and KRECs were quantified. The TRECs values ranged between 1 and 1,006 TRECs/µL, with mean and median of 160 and 139 TRECs/µL, respectively. Three samples from patients with severe combined immunodeficiency (SCID) showed TRECs below 4/µL and a patient with DiGeorge syndrome showed undetectable TRECs. KRECs values ranged from 10 to 1,097 KRECs/µL, with mean and median of 130 and 108 KRECs/µL. Four patients with agammaglobulinemia had results below 4 KRECs/µL. The cutoff values were 15 TRECs/µL and 14 KRECs/µL and were established according to the receiver operating characteristic curve analysis, with 100% sensitivity for SCID and agammaglobulinemia detection, respectively. Conclusions: Quantification of TRECs and KRECs was able to diagnose children with T- and/or B-cell lymphopenia in our study, which validated the technique in Brazil and enabled us to implement the newborn screening program for SCID and agammaglobulinemia.

Neonatal screening for severe combined immunodeficiency in Brazil / Triagem neonatal para imunodeficiência combinada grave no Brasil

Abstract Objective To apply, in Brazil, the T-cell receptor excision circles (TRECs) quantification technique using real-time polymerase chain reaction in newborn screening for severe combined immunodeficiency and assess the feasibility of implementing it on a large scale in Brazil. Methods 8715 newborn blood samples were collected on filter paper and, after DNA elution, TRECs were quantified by real-time polymerase chain reaction. The cutoff value to determine whether a sample was abnormal was determined by ROC curve analysis, using SSPS. Results The concentration of TRECs in 8,682 samples ranged from 2 to 2,181 TRECs/µL of blood, with mean and median of 324 and 259 TRECs/µL, respectively. Forty-nine (0.56%) samples were below the cutoff (30 TRECs/µL) and were reanalyzed. Four (0.05%) samples had abnormal results (between 16 and 29 TRECs/µL). Samples from patients previously identified as having severe combined immunodeficiency or DiGeorge syndrome were used to validate the assay and all of them showed TRECs below the cutoff. Preterm infants had lower levels of TRECs than full-term neonates. The ROC curve showed a cutoff of 26 TRECs/µL, with 100% sensitivity for detecting severe combined immunodeficiency. Using this value, retest and referral rates were 0.43% (37 samples) and 0.03% (3 samples), respectively. Conclusion The technique is reliable and can be applied on a large scale after the training of technical teams throughout Brazil.

Resumo Objetivo Aplicar no Brasil a técnica de quantificação de T-cell Receptor Excision Circles (TRECs) por PCR em tempo real para triagem neonatal de imunodeficiência combinada grave (SCID) e avaliar se é possível fazê-la em grande escala em nosso país. Métodos Foram coletadas em papel filtro 8.715 amostras de sangue de recém-nascidos e, após eluição do DNA, os TRECs foram quantificados por PCR em tempo real. O valor de corte para determinar se uma amostra é anormal foi determinado pela análise de curva ROC com o programa SSPS. Resultados A concentração de TRECs em 8.682 amostras analisadas variou entre 2 e 2.181 TRECs/µL de sangue, com média e mediana de 324 e 259 TRECs/µL, respectivamente. Das amostras, 49 (0,56%) ficaram abaixo do valor de corte (30 TRECs/µL) e foram requantificadas. Quatro (0,05%) mantiveram resultados anormais (entre 16 e 29 TRECs/µL). Amostras de pacientes com diagnóstico clínico prévio de SCID e síndrome de DiGeorge foram usadas para validar o ensaio e todas apresentaram concentração de TRECs abaixo do valor de corte. Recém-nascidos prematuros apresentaram menores níveis de TRECs comparados com os nascidos a termo. Com o uso da curva ROC em nossos dados, chegamos ao valor de corte de 26 TRECs/µL, com sensibilidade de 100% para detecção de SCID. Com o uso desse valor, as taxas de repetição e encaminhamento ficaram em 0,43% (37 amostras) e 0,03% (3 amostras), respectivamente. Conclusão A técnica é factível e pode ser implantada em grande escala, após treinamento técnico das equipes envolvidas.

Imunodeficiência combinada grave: uma revisão da literatura / Severe combined immunodeficiency: review of the literature

A imunodeficiência combinada grave (SCID) é uma condição clínica caracterizada por marcante comprometimento da resposta imune envolvendo linfócitos T e/ou B e/ou células NK, que conduza aumento da susceptibilidade a infecções e alta taxa de mortalidade em crianças acometidas. Dificuldades na interpretação dos sintomas clínicos e na identificação de mutações genéticas, devido à ampla variedade fenotípica e genotípica da doença, representam obstáculos para o diagnóstico. Por outro lado, o tratamento é realizado de forma independente da identificação de mutação genética. O objetivo do presente trabalho foi revisar aspectos fisiopatológicos, métodos diagnósticos e tratamentos utilizados em pacientes com SCID. A revisão foi realizada com base em levantamento bibliográfico de banco de dados indexados disponíveis na Internet incluindo LILACS, MEDLINE, PubMed, SciELO Brasil, periódicos CAPES e Cochrane, e foi conduzida com os seguintes critérios de inclusão: artigos científicos publicados nos idiomas português e inglês, dentro do período de 1963 a 2014 e que possuíam as palavras-chave “Imunodeficiência Combinada Grave”, “SCID”, “Leucopenia”, “Diagnóstico”, “Tratamento” e “Transplante de medula óssea”. O levantamento bibliográfico revelou dificuldades no diagnóstico clínico, laboratorial e genético-molecular, e ressaltou a importância do diagnóstico precoce conduzindo ao tratamento adequado. O diagnóstico precoce da SCID tem papel crucial na melhora da qualidade de vida e na sobrevida dos pacientes, além de favorecer intervenções terapêuticas que previnem o surgimento de infecções e complicações clínicas subsequentes...

Severe combined immunodeficiency (SCID) is a clinical condition characterized by marked impairment of immune responses involving T and/or B lymphocytes and/or NK cells, leading to increased susceptibility to infections and a high mortality rate among affected infants. Difficulties in the interpretation of clinical symptoms and in the detection of genetic mutations make diagnosis a challenge because of the phenotypic and genotypic heterogeneity associated with the disease. Treatment is performed regardless of the detection of a genetic mutation. The objective of the present study was to review pathophysiological aspects, diagnostic methods, and therapies used in patients with SCID. The review included papers available in online databases, including LILACS, MEDLINE, PubMed, SciELO Brazil, Periódicos CAPES, and Cochrane. Papers were searched considering the following inclusion criteria: research articles published in Portuguese or English, between years 1963 and 2014, containing the keywords "Severe Combined Immunodeficiency," "SCID," "Leukopenia," "Diagnosis," "Treatment," and "Bone Marrow Transplantation." The review revealed difficulties in clinical, biochemical, and molecular genetic diagnosis, and emphasized the importance of early diagnosis leading to appropriate treatment. Early diagnosis of SCID is crucial to improve the quality of life and survival of patients, and it allows the use of therapeutic interventions that prevent the onset of infections and subsequent clinical complications...

Omenn syndrome with mutation in RAG1 gene.

Omenn syndrome is a form of severe combined immunodeficiency associated with erythrodermia, hepatosplenomegaly, lymphadenopathy, and alopecia. Inherited hypomorphic mutations in the recombination activating genes 1 and 2 (RAG1 and RAG2) and in ARTEMIS genes and more recently defects in IL7RA, and RMRP genes have been described to be responsible of this peculiar immunodeficiency. The authors report here a Moroccan patient of four-months-old with classical features of Omenn syndrome, carrying a deletion at the N terminal part of RAG1. Early recognition of this condition is important for genetic counseling and early treatment.

Acute myocardial ischemia following accidental intravenous administration of epinephrine in high concentration.

Inadvertent and accidental epinephrine overdose might result in potentially lethal complications. We present a case of acute epinephrine toxicity resulting in acute myocardial ischemia in a young boy with combined variable immunodeficiency syndrome who developed severe allergic reaction to intravenous immunoglobulin, and was subsequently given epinephrine by mistake intravenously rather than subcutaneously. He developed significant ischemic changes in standard 12-lead electrocardiogram, transiently raised cardiac enzymes, reduced left ventricular systolic function, pulmonary edema and pulmonary hemorrhage. It is suggested that special precautionary measures should be taken regarding the dose and the route while administering epinephrine to avoid mishaps.

Trasplante de células progenitoras hematopoyéticas en pediatría: Una alternativa de tratamiento en inmunodeficiencias primarias / Hematopoietic stem cell transplant in combined immunodeficiency syndromes of childhood: An optimal treatment for primary immunodeficiency

The congenital immunodeficiency disorders in which the defect has been clearly traced to the stem cell can be cured with allogeneic stem-cell transplantation (SCT) from an unaffected donor. Widespread application of this treatment modality has been tempered by the fact that risk-benefit considerations do not always favor a procedure that carries a significant risk for morbidity and mortality. Some malignant disorders of childhood eventually have to be treated by an autologous or allogeneic SCT, however nonmalignant disorders can also be treated with this approach. This article reviews the current status of SCT for nonmalignant inherited immunodeficiency disorders.

Tradicionalmente el trasplante de células progenituras hematopoyéticas (TCPH) se ha utilizado en pacientes pediátricos para el tratamiento de padecimientos malignos. Sin embargo, también existen indicaciones y experiencia para padecimientos benignos dentro de los cuales se encuentran los síndromes de inmunodeficiencia combinada primaria. Estos síndromes de la infancia constituyen una serie de padecimientos que aun cuando son infrecuentes en la patología infantil constituyen un grupo de alteraciones que hasta hace más de tres décadas eran irremediablemente fatales. Con el advenimiento del TCPH el pronóstico de estos síndromes ha mejorado sustancialmente, por lo que es importante conocer sus resultados, así como su morbimortalidad asociada.

Severe combined immunodeficiency. King Hussein medical center experience

To describe the clinical experience of a single center in severe combined Immunodeficiency. a total of 14 patients who were admitted to the Pediatric Department at King Hussein Medical Center with a probable diagnosis of severe combined immunodeficiency over 6 years duration were studied. The study descried patients' population, clinical, family history, laboratory and radiological investigations, treatment options and prognosis. Twelve [86 percent] patients were males and two [14 percent] were females. Median age at presentation was 21 weeks. They all showed the same clinical presentation with few exceptions. We demonstrated maternofetal engraftment in two [14 percent] patients. Unusual post vaccination poliomyelitis type II was demonstrated in one patient. Skin abscess and deep-seated ulcers were seen in one patient. One patient with Viral Associated Hemophagocytosis Syndrome Dead siblings with similar illness were retrieved in most patients had anemia, lymphopnia, and severe pan-hypogammaglobulinemia at time of presentation. We confirmed neutropenia in only three [21 percent] patients. Blood cultures revealed heavy growth of Klebsiella and Pseudomonas organisms in nine [64 percent] patients. We found that intravenous immunoglobulins administration was partially useful. Bone marrow transplant was not done for any patient. One patient was under preparation for autologous bone marrow transplantation. Eleven patients died after a mean of four months after diagnosis. Two patients were in a relatively acceptable condition, and that last one was suffering from fulminant sepsis. The awareness of the referring physicians to immunodeficiency is sub optimal. Pediatricians are urged to pay attention to persistent Lymphopenia as a helpful clue for the diagnosis of severe combined Immunodeficiency in infants with unusual infections especially in families with positive family history. Live attenuated viral or bacterial immunization is contradicted in suspected immunodeficiency. Health education of families is an essential part of management of these patients

X-linked Severe Combined Immunodeficiency Syndrome: The First Korean Case with gamma c Chain Gene Mutation and Subsequent Genetic Counseling

X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID.

Imunodeficiência combinada grave (IDCG) - Relato de seis casos / Severe combined immunodeficiency (SCID) - Report of six cases

Objetivo: Descrever seis casos de imunodeficiência combinada grave, alertando para o diagnóstico e terapêutica precoces. Metodologia: Säo descritos seis pacientes com imunodeficiência combinada grave (IDCG) admitidos na Unidade de Alergia e Imunologia do Instituto da Criança do Departamento de Pediatria da FMUSP, cujos principais dados que levaram a esta hipótese diagnóstica foram história familiar, manifestaçöes clínicas, hemograma e dosagem de imunoglobulinas. Todos os pacientes foram submetidos a um protocolo clínico e laboratorial de avaliaçäo para imunodeficiência. Resultados: A idade de ínicio do quadro clínico variou do nascimento a oito meses e a idade do diagnóstico de um a onze meses. Quatro pacientes eram do sexo masculino e dois do sexo feminino. História familiar de óbito de irmäos, por quadro infeccioso, no primeiro ano de vida esteve presente em três casos. As manifestaçöes clínicas mais comuns foram: septicemia, pneumonia grave, diarréia crônica e desnutriçäo protéico-calórica. Os principais achados laboratoriais foram linfopenia e diminuiçäo das imunoglobulinas. Todos os pacientes receberam reposiçäo de gamaglobulina endovenosa, antibioticoterapia de amplo espectro e cuidados nutricionais. O óbito ocorreu em cinco casos, sendo quatro antes da realiazaçäo do transplante de medula óssea (TMO). Conclusäo: A imunodeficiência combinada grave é uma emergência pediátrica, sendo que o diagnóstico precoce e a instituiçäo de medidas específicas, incluindo a realizaçäo do TMO, permitem melhor evoluçäo desta doença.

Trasplante de médula ósea en pacientes portadores de inmunodeficiencias severas combinadas / Bone marrow transplantation in patients with severe combined immunodeficiency

La inmunodeficiencia severa combinada (IDSC) es una inmunodeficiencia primaria cuya evolución clínica es mortal si no se realiza un tratamiento con trasplante de médula ósea (TMO). En los últimos 8 años cuatro pacientes de sexo masculino han sido sometidos a TMO, dos de ellos con donante idéntico (hermanos) y los otros dos con médula obtenida de sus respectivas madres (haploidéntico). Como elementos de importancia deben mencionarse la presencia de diseminación de la vacuna BCG en dos de ellos, una paraproteinemia de predominio IgM en un caso y la identificación de una quimera por linfocitos maternos en otro niño. En los cuatro casos existía compromiso pulmonar de importancia, con secuelas tipo bronquiectasias en dos de ellos. Dos pacientes que recibieron TMO idéntico normalizaron su trastorno inmunológico al mes y tres meses de haber recibido el TMO, encontrándose en la actualidad sanos con un tiempo de seguimiento de 1 y 7 años respectivamente. Los otros dos enfermos trasplantados con médula no idéntica fallecieron de complicaciones atribuibles a infecciones y al daño pulmonar existente, al 1 y 2 meses de efectuarse el TMO. Las implicancias prácticas del diagnóstico de la IDSC y los aspectos más importantes del TMO son comentados

case report of common variable immunodeficiency [CVID] with leukocytes adhesion disorders [LADS]

A three year old boy with delayed separation of the umbilical cord, recurrent pyogenic infections and common variable immunodeficiency is presented. The immunoglobulin measurement was severely abnormal. To the best of our knowledge, the existence of leukocyte adhesion disorder together with common variable immunodeficiency [CVID] in a patient has not been reported prior to this study