In a study of 9 glycosidases [.gamma.-mannosidase, .gamma.-L-fucosidase, .beta.-n-acetylglucosaminidase, .beta.-n-acetylqalactoseaminidase, .beta.-glucuronidase, .beta.-galactosidase, .alpha.-glucosidase, arylsulfatase and acid phosphatase] in serum samples from 72 cystic fibrosis (CF) patients, 85 CF parents and 34 healthy and diseased controls, significant elevations of mean .alpha.-glucosidase levels were found in CF patients. No other glycosidases showed any significant change. Mean .alpha.-glucosidase levels in obligate heterozygotes were the same as in control individuals. .alpha.-Glucosidase levels in CF patients correlated with the degree of clinical impairment as measured by the Schwachman score.
