[A study of antielastase activity in the development of pulmonary emphysema in a family with alpha 1-antitrypsin deficiency].

: The five siblings of a family with alpha 1-antitrypsin deficiency including three of Pi- and two of PiM- phenotypes, were studied for the development of pulmonary emphysema during nine years. The changes of pulmonary function showed significant decrease in FEV1.0 and V50, and increase in RV/TLC. Clinical diagnoses for each patient were assessed by pulmonary function, inhalation and perfusion lung scintigram. Two case of Pi- phenotypes were diagnosed definite pulmonary emphysema 9 years previously, in one case of Pi- emphysema was suspected and two PiM- cases were also suspected of emphysema. alpha 1-antitrypsin and elastase inhibitory capacity (EIC) were investigated in serum and bronchoalveolar lavage fluids (BALF) from four patients with alpha 1-antitrypsin deficiency, healthy non-smokers and smokers. alpha 1-Antitrypsin and EIC in BALF in patients with alpha 1-antitrypsin deficiency were markedly decreased. There were no differences between non-smokers and smokers in alpha 1-antitrypsin and EIC, but EIC in BALF showed a significant correlation with DLCO or %DLCO. These findings suggest that a deficiency of alpha 1-antitrypsin results in insufficient antielastase protection in the lower respiratory tract, and EIC in BALF may be useful for detecting early changes of emphysema.