University of Massachusetts Medical School Faculty Publications


Evolution of pancreatic function during the first year in infants with cystic fibrosis

UMMS Affiliation

Department of Medicine, Division of Preventive and Behavorial Medicine; Department of Pediatrics

Publication Date


Document Type



Cohort Studies; Cystic Fibrosis; Docosahexaenoic Acids; Exocrine Pancreatic Insufficiency; Feces; Female; Genotype; Homozygote; Humans; Infant; Infant, Newborn; Longitudinal Studies; Male; Neonatal Screening; Pancreatic Elastase; Pancreatic Function Tests


Congenital, Hereditary, and Neonatal Diseases and Abnormalities | Pediatrics | Respiratory Tract Diseases


OBJECTIVE: To describe pancreatic function during the first year of life in infants diagnosed with cystic fibrosis (CF) using serial fecal elastase measurements.

STUDY DESIGN: This was a longitudinal study of 82 infants diagnosed with CF through newborn screening. Monthly stool samples were sent to a central laboratory for fecal elastase measurements.

RESULTS: A total of 61 infants had an initial stool sample obtained at age 9 months. Twenty-six of 29 infants with a fecal elastase value /g at study entry had a fecal elastase value /g (the accepted cutoff value for pancreatic insufficiency) on all measurements during the year; all 29 had a value /g at the end of the study. Of the 48 infants with initial fecal elastase value /g, 13 had at least 1 fecal elastase value >200 mug/g but had a final stool fecal elastase value /g; however, 4 infants with an initial fecal elastase value /g ended the year with a value >200 mug/g. Eleven of 13 infants with an initial fecal elastase value of >200 mug/g still had a value >200 mug/g at the end of the first year.

CONCLUSION: Infants with CF exhibit variability in fecal elastase values during the first year. Infants with a fecal elastase level of 50-200 mug/g at diagnosis should be treated with pancreatic enzyme replacement therapy, but fecal elastase should be remeasured at age 1 year to ensure that those with a falsely low value do not continue to receive pancreatic enzyme replacement therapy unnecessarily. Those with a fecal elastase value >200 mug/g initially can become pancreatic insufficient with time.

DOI of Published Version



J Pediatr. 2013 Apr;162(4):808-812.e1. doi: 10.1016/j.jpeds.2012.10.008. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Journal/Book/Conference Title

The Journal of pediatrics

PubMed ID