Eosinophilic alveolitis in BAL after lung transplantation

Lung transplantation has become a therapeutic option for patients with end stage lung disease. However, outcome after transplantation is complicated b y episodes of rejection and infections. Bronchoalveolar lavage is a valuabl e tool in monitoring patients after transplantation, since it allows the de tection of pathogens. A marker specifically indicating rejection from chang es in BAL fluid has not been found yet. Especially changes in differential cell count, like lymphocytosis or an increase in polymorphnuclear granulocy tes, are unspecific. The role of high eosinophil levels in BAL has not been elucidated yet. We analyzed 25 BAL samples and clinical data of 4 patients who underwent lu ng transplantation and presented with recurrent episodes of eosinophilic al veolitis in BAL. All patients demonstrated a deterioration of clinical cond ition, lung function, and blood gas analysis during rimes of eosinophilia i n BAL, compared to previous examinations. In all cases, eosinophilia in BAL was accompanied by rejection. All patients were finally treated with high doses of steroids, resulting in improvement of all parameters. Eosinophilia was not associated with significant changes in the IL-5 concentration in B AL or the pattern of IL-5 expression in BAL cells. In conclusion, eosinophi lic alveolitis may indicate acute rejection in patients after lung transpla ntation, if other causes of eosinophilia are excluded.