An increase in pulmonary circulation hydrostatic pressure is a frequent complication of severe renal impairment and left heart failure, sometimes creating the clinical and radiologic features of pulmonary edema. Studies of animal models have demonstrated the relationship between the increase in hydrostatic pressure in the pulmonary circulation and the occurrence of AH, showing “capillary stress failure” characterized by structural alteration of capillary basal membrane collagen IV. In this study, AH was present in all the BAL fluid samples obtained from patients with hydrostatic pulmonary edema. Edema was associated with HIV-related dilated cardiomyopathy (n = 3) and severe renal failure (n = 5) due to idiopathic focal and segmental glomerulosclerosis and hyalinosis. It is noteworthy that vasculitis, and especially pulmonary capillaritis, has never been reported in these so-called HIV-associated glomerular diseases. asthma inhalers
It is interesting that AH can be associated with all AIDS-related pulmonary disorders, even those in which the pulmonary vessels are never involved (ie, PCP and bacterial pneumonia). In a previous series involving uninfected HIV-immunocompromised patients, AH triggering factors included smoking,’ renal failure,” and, especially, all causes of clotting disorders (ie, disseminated intravascular coagulation, profound thrombocytopenia, and treatment with anticoagulants, antiplatelet agents, and fibrinolytics).’ Except for smoking, the present study confirms the role of these factors in patients with AIDS-related AH (Table 2). After multivariate analysis, only thrombocytopenia was an independent risk factor (OR, 5.6) (Table 4).
In conclusion, AH is a frequent finding in BAL specimens from HIV-infected patients with pulmonary symptoms and/or fever. However, the AH is usually occult and mild, and does not affect survival.