Rate and predictors of quantity not sufficient of sweat for chloridrometry in very young infants

Abstract

The Cystic Fibrosis Foundation (CFF) defines a quantity not sufficient (QNS) of sweat as a sample weighting lower than 75 mg, whose rate should be lower than 10% for infants younger than three months. This study aimed to verify the rate and factors associated with QNS for chloridrometry among very young babies from a low-prevalence resource-limited setting.We recruited prospectively and consecutively newborns and young infants younger than three months undergoing coulometry assays after two abnormal immunoreactive trypsinogen results. Explanatory variables were gender, gestational age (<37 or >37 weeks), birth weight (<2.500 g or >2.500 g), weight on the day of sweat collection (<2.500 g or >2.500 g), age upon the sweat test (<43 M a n u s c r i p t a c c e p t e d f o r p u b l i c a t i o n