Screening for cystic fibrosis by analysis of albumin in meconium.

A clinical study of the albumin content in meconium was performed on two categories of newborn infants: a screening series of 8,830 infants and a high-risk group for Cystic Fibrosis (CF) of 70 infants. A single radial immunodiffusion technique and test strips were used. Three CF infants were detected in the screening series (1:3,000) and 16 in the high-risk group. The diagnostic accuracy for CF was fairly good. The specificity was 99.8% for the immunodiffusion technique and 99.2% for test strips. A high concentration of albumin in meconium was found not only in CF but also in preterm babies and infants with gastrointestinal disturbances, such as atresias, malaena neonatorum and malabsorption syndromes. The sensitivity was 90% for the immunodiffusion technique and 78% for the test strip. False-negative results were probably due to proteolytic activity and might be avoided if the samples are stored at a low temperature before analysis. CF screening of all meconiums by the use of test strips followed by analysis of positive tests by the immunodiffusion technique is suggested.