CRMS / CFSPID is diagnosed in infants who have a positive newborn screen, are asymptomatic, and have either of the following: Sweat chloride concentrations in the intermediate range and 0 or 1 CF-causing variant Sweat chloride concentrations in the normal range and 2 CFTR variants, at least 1 of which has unclear phenotypic consequences Most children with CRMS / CFSPID remain healthy, but over time around 10% will develop symptoms and meet criteria for a diagnosis of CF or a CF-related disorder.