RESUMO
Hypothesizing a pathophysiological role of anti-topoisomerase I antibodies (anti-topo I) through autoantibody-dependent cell-mediated cytotoxicity (ADCC) and cytotoxic effectors expressing receptors for the Fc portion of IgG in systemic sclerosis (SSc), 267 SSc patients (56 with anti-topo I and 102 with anti-centromere antibodies (ACA)) were genotyped for the functional FCGR3A-V158F polymorphism. A descriptive analysis of patients according to their clinical and immunological status and FCGR3A-158 V/F genotypes was performed using multiple correspondence analysis. This descriptive analysis revealed an association between the FCGR3A-158 VV genotype and the presence of anti-topo I. By contrast, no relationship was found between FCGR3A polymorphism and the presence of ACA. SSc patients with anti-topo I appear to be more frequently homozygous for the high-affinity FcγRIIIA-coding allele, suggesting that some autoantibodies may be pathogenic through ADCC.
Assuntos
DNA Topoisomerases Tipo I/imunologia , Estudos de Associação Genética , Receptores de IgG/genética , Escleroderma Sistêmico/genética , Adulto , Idoso , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Autoanticorpos/imunologia , Centrômero/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Receptores de IgG/imunologia , Escleroderma Sistêmico/imunologiaRESUMO
Pulmonary embolism is the main pulmonary manifestation of primary antiphospholipid syndrome. Other pulmonary manifestations including intra-alveolar haemorrhage are less common. We report a 36-year-old man with a primary antiphospholipid syndrome who presented with an acute respiratory failure due to the association of pulmonary embolism and intra-alveolar haemorrhage. This diagnosis should be systematically considered as it is life threatening and requires a specific therapy.