RESUMO
Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, also known as drug induced hypersensitivity (DiHS) syndrome is a severe delayed hypersensitivity reaction with potentially fatal consequences. Whilst recognised as T cell-mediated, our understanding of the immunopathogenesis of this syndrome remains incomplete. Here, we discuss models of DRESS, including the role of human leukocyte antigen (HLA) and how observations derived from new molecular techniques adopted in key studies have informed our mechanism-based understanding of the central role of Herpesviridae reactivation and heterologous immunity in these disorders.
Assuntos
Síndrome de Hipersensibilidade a Medicamentos/etiologia , Eosinofilia/induzido quimicamente , Infecções por Herpesviridae/imunologia , Linfócitos T/efeitos dos fármacos , Síndrome de Hipersensibilidade a Medicamentos/diagnóstico , Síndrome de Hipersensibilidade a Medicamentos/virologia , Eosinofilia/imunologia , Antígenos HLA/imunologia , Herpesviridae/efeitos dos fármacos , Herpesviridae/fisiologia , Infecções por Herpesviridae/complicações , Humanos , Receptores de Antígenos de Linfócitos T , Linfócitos T/imunologia , Replicação Viral/efeitos dos fármacosRESUMO
Most patients with autosomal dominant hyper-IgE syndrome (AD-HIES) carry rare heterozygous STAT3 variants. Only six of the 135 in-frame variants reported have been experimentally shown to be dominant negative (DN), and it has been recently suggested that eight out-of-frame variants operate by haploinsufficiency. We experimentally tested these 143 variants, 7 novel out-of-frame variants found in HIES patients, and other STAT3 variants from the general population. Strikingly, all 15 out-of-frame variants were DN via their encoded (1) truncated proteins, (2) neoproteins generated from a translation reinitiation codon, and (3) isoforms from alternative transcripts or a combination thereof. Moreover, 128 of the 135 in-frame variants (95%) were also DN. The patients carrying the seven non-DN STAT3 in-frame variants have not been studied for other genetic etiologies. Finally, none of the variants from the general population tested, including an out-of-frame variant, were DN. Overall, our findings show that heterozygous STAT3 variants, whether in or out of frame, underlie AD-HIES through negative dominance rather than haploinsufficiency.
Assuntos
Genes Dominantes , Síndrome de Job/genética , Mutação/genética , Fator de Transcrição STAT3/genética , Adolescente , Adulto , Alelos , Processamento Alternativo/genética , Criança , Pré-Escolar , Códon sem Sentido/genética , Evolução Molecular , Família , Feminino , Mutação da Fase de Leitura/genética , Genética Populacional , Células HEK293 , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Linhagem , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Muscular polyarteritis nodosa where disease is isolated to skeletal muscle is a rare and often poorly recognised clinical entity. Patients typically present with fever and severe muscle pain limiting ability to ambulate without rise in creatine kinase. Often there is a significant delay between presentation and diagnosis, which requires histological confirmation. Musculoskeletal MRI is a sensitive investigation that can lead to timely biopsy and improve diagnostic yield. Early diagnosis of this condition is essential as patients typically respond favourably to corticosteroid treatment. Here we report 4 cases of muscular polyarteritis nodosa and review the reported literature.