RESUMO
The genetic investigation of a family presenting with a dominant form of hyper IgM syndrome published in 1963 and 1975 revealed a R190X nonsense mutation in activation-induced cytidine deaminase. This report illustrates the progress made over 6 decades in the characterization of primary immunodeficiencies, from immunochemistry to whole-exome sequencing.
Assuntos
Citidina Desaminase/genética , Disgamaglobulinemia/genética , Previsões , Síndromes de Imunodeficiência/complicações , Mutação , Citidina Desaminase/metabolismo , Análise Mutacional de DNA , Disgamaglobulinemia/complicações , Disgamaglobulinemia/metabolismo , Feminino , Seguimentos , Humanos , Pessoa de Meia-IdadeRESUMO
Hyper-IgM (HIGM) syndrome is a heterogeneous group of disorders characterized by normal or elevated serum IgM levels associated with absent or decreased IgG, IgA and IgE. Here we summarize data from the HIGM syndrome Registry of the Latin American Society for Immunodeficiencies (LASID). Of the 58 patients from 51 families reported to the registry with the clinical phenotype of HIGM syndrome, molecular defects were identified in 37 patients thus far. We retrospectively analyzed the clinical, immunological and molecular data from these 37 patients. CD40 ligand (CD40L) deficiency was found in 35 patients from 25 families and activation-induced cytidine deaminase (AID) deficiency in 2 unrelated patients. Five previously unreported mutations were identified in the CD40L gene (CD40LG). Respiratory tract infections, mainly pneumonia, were the most frequent clinical manifestation. Previously undescribed fungal and opportunistic infections were observed in CD40L-deficient patients but not in the two patients with AID deficiency. These include the first cases of pneumonia caused by Mycoplasma pneumoniae, Serratia marcescens or Aspergillus sp. and diarrhea caused by Microsporidium sp. or Isospora belli. Except for four CD40L-deficient patients who died from complications of presumptive central nervous system infections or sepsis, all patients reported in this study are alive. Four CD40L-deficient patients underwent successful bone marrow transplantation. This report characterizes the clinical and genetic spectrum of HIGM syndrome in Latin America and expands the understanding of the genotype and phenotype of this syndrome in tropical areas.
Assuntos
Síndrome de Imunodeficiência com Hiper-IgM/epidemiologia , Ligante de CD40/deficiência , Ligante de CD40/genética , Pré-Escolar , Comorbidade , Citidina Desaminase/deficiência , Citidina Desaminase/genética , Feminino , Hispânico ou Latino , Humanos , Síndrome de Imunodeficiência com Hiper-IgM/complicações , Síndrome de Imunodeficiência com Hiper-IgM/diagnóstico , Síndrome de Imunodeficiência com Hiper-IgM/terapia , Lactente , Recém-Nascido , Infecções/diagnóstico , Infecções/etiologia , Pulmão/patologia , Masculino , Sistema de Registros , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
HyperIgM syndrome is a heterogenous immunodeficiency characterized by impaired class-switch recombination due to different molecular abnormalities. We report on two female patients affected by a novel syndrome associating HIGM, growth and pubertal disturbances, and severe lymphoid hyperplasia with eventual development into lymphomas, suggesting a DNA repair defect.