RESUMO
Objective To investigate the prevalence of anti-endothelial cell antibody fAECA) in the sera of patients with connective tissue diseases(CTD)complicated with pulmonary arterial hyperten-sion (PAH)and to detect the specific antigens of AECA which may be related to clinical manifestations.Methods AECA was detected with Western blotting in 39 CTD patients with PAH.22 CTD patients without PAH and 30 healthy donors.Results The prevalence of AECA was 82%in CTD patients with PAH.73%in CTD patients without PAH and 20%in healthy donors.Anti-22 000 AECA was only detected in CTD patients with PAH(15%).Anti-75 000 AECA was more frequently detected in CTD patients with PAH than in thosewithout PAH(51%vs 23%.P＜0.05).In CTD patients complicated with PAH.anti-75 000 AECA was morefrequently detected in those with Raynaud's phenomenon or with positive anti-RNP antibody.Conclusion AECA can be more frequently detected in CTD patients with or without PAH.Furthermore,anti-22 000 and anti-75 000 AECA may play a special role in CTD patients with PAH.