High prevalence of pulmonary diffusion abnormalities without interstitial changes in long-term survivors of liver transplantation

Abnormalities in lung function are frequent findings in patients with termi nal stage chronic liver disease. While spirometric parameters improve early after liver transplantation, a reduction in diffusion capacity has been re ported up to 15 months after transplantation. It ib unknown to what extent this disturbance in gas exchange occurs among, long term survivors after li ver transplantation. We assessed lung function in terms of spirometry, and gas exchange as well as pulmonary morphology by high resolution computed to mography (HRCT) in 40 patients 38 months (median, range 20-147 months) afte r liver transplantation. The prevalence of restrictive or obstructive chang es was not different from predicted values. For the whole group of longterm survivors the carbon monoxide transfer coefficient (KCO) was reduced to 71 .3 + 12.0 % predicted (P < 0.05). HRCT revealed interstitial changes in onl y 2/40 (5.0 %), emphysematous bullae in 2/40 (5.0 %) and pleural thickening in 9/40 (22,5 %). Diffusion abnormalities are prevalent in the majority of patients after liver transplantation, whereas spirometric abnormalities ar e absent also in the long term. The high prevalence of impaired gas exchang e and the absence of interstitial lesions imply that changes in pulmonary b lood vessels are the most likely cause.