ABSTRACT
The association between autoimmunity and pulmonary arterial hypertension (PAH) has been appreciated for >40 yrs, but how autoimmune injury might contribute to the pathogenesis of this disease has only been examined in a case-specific manner. It is becoming increasingly clear that a variety of diverse clinical diseases, ranging from viral infections to connective tissue disorders, can culminate in pulmonary vascular pathology that is indistinguishable. Is there a hitherto unappreciated biology that unites these seemingly unrelated conditions? The answer to this question may come from the increasing body of evidence concerned with the central importance of regulatory T-cells in preventing inappropriate B-cell activity. Two striking similarities between conditions associated with severe angioproliferative pulmonary hypertension are a defect in the CD4 T-cell compartment and auto-antibody production. Pathogenic auto-antibodies targeting endothelial cells are capable of inducing vascular endothelial apoptosis and may initiate the development of PAH. The present review will focus on what is known about autoimmune phenomena in pulmonary arterial hypertension patients, in order to better consider whether an early loss of self-tolerance followed by autoimmune injury could influence the early development of severe angioproliferative pulmonary hypertension.
Subject(s)
Autoimmune Diseases/epidemiology , Autoimmunity/immunology , Hypertension, Pulmonary/epidemiology , Hypertension, Pulmonary/pathology , Adult , Age Distribution , Aged , Autoimmune Diseases/diagnosis , Biopsy, Needle , Comorbidity , Female , Humans , Hypertension, Pulmonary/immunology , Immunohistochemistry , Male , Middle Aged , Prevalence , Prognosis , Risk Assessment , Severity of Illness Index , Sex Distribution , Survival AnalysisABSTRACT
Primary pulmonary hypertension (PPH) and Castleman's disease (CD) are rare conditions infrequently encountered in clinical practice. In this paper, two patients diagnosed with both of these diseases are reported. The authors speculate that rather than being a chance occurrence, these conditions are linked by a common angio-proliferative mechanism. Therefore, an association between infection with the human herpesvirus-8 and the diseases of PPH and CD was sought. Evidence of human herpesvirus-8 infection was found in the lung tissue and, specifically, in the plexiform lesions from one of the patients.
