AIDS-Related Alveolar Hemorrhage: CMV
The apparent conflict with the results of another study might simply reflect differences in the status of the patients studied, as bleeding complications are mainly reported in those with advanced pulmonary diseases. The association between AH and pulmonary KS is clearly explained by pathologic studies. KS lesions are characterized by the proliferation of endothelial and spindle cells and by the extravasation of erythrocytes into the alveolar spaces. Interestingly, human herpesvirus type 8, which is consistently detected in KS lesions, can promote both angiogenesis and vessel permeability by activating its encoded G-protein-coupled receptor. Moreover, spindle cells produce several mediators (interleukin-1, interleukin-6, fibroblast growth factor, and vascular endothelial growth factor) that influence endothelial cell proliferation and permeability. buy claritin online
Although CMV is frequently recovered from the lung, CMV pneumonia is rare in HIV-infected pa-tients. We have previously demonstrated that AH can be associated with diffuse thrombotic microangiopathy related to specific CMV infection of lung capillary endothelial cells. In the present study, all the patients with CMV-associated AH had similar clinical features, except for a patient who also had symptomatic pulmonary KS. Thus, the detection of both AH and CMV in BAL fluid would point to CMV-induced AH, especially in a patient with thrombotic microangiopathy. Pulmonary invasive aspergillosis is another angioinvasive infection leading to pulmonary complications in HIV-infected pa-tients. Although statistically meaningless, it is noteworthy that both patients with invasive pulmonary aspergillosis in this series had AH.