ENDOTHELIN IN BRONCHOALVEOLAR LAVAGE FLUID IS INCREASED IN LUNG-TRANSPLANTED PATIENTS

Animal studies have shown increased endothelin in bronchoalveolar lava ge (BAL) fluid during unmodified rejection. We performed radioimmunoas say of endothelin in 59 BAL fluid samples from ten patients at differe nt times after lung transplantation. All patients received immunosuppr essive therapy (cyclosporin, azathioprine and methylprednisolone). Ref erence BAL samples were obtained from six controls. Of the 59 test sam ples, five were collected during rejection episodes, confirmed by clin ical outcome, BAL cytology and radiology (rejection group), and 19 wer e taken during bacterial, viral or fungal infection (infection group). The endothelin content of BAL (pg/ml) was significantly greater in th e rejection group than in the infection group (61.1 +/- 3.8 vs 40.6 +/ - 2.0) or in the 35 samples taken in uncomplicated course after lung t ransplantation (40.9 +/- 5.4), p < 0.01. The endothelin level in BAL. fluid from the controls was only 3.0 +/- 1.4 pg/ml, significantly less (p < 0.005) than in all the lung-transplanted groups. Endothelin in B AL fluid thus was increased after lung transplantation, and still furt her during rejection.