CFTR and cystic fibrosis: This is the case of an 8-year-old female followed at the Cystic Fibrosis Regional Reference Centre of Florence, Italy (Meyer Children’s Hospital IRCCS), initially diagnosed as CF transmembrane conductance regulator (CFTR)-related metabolic syndrome/cystic fibrosis screen positive, inconclusive diagnosis (CMRS/CFSPID) [22] in the presence of positive CF newborn screening, sweat chloride in the intermediate range (49–42 mmol/L) and CFTR genotype: F508del/S737F (less than two CFTR-causing variants) [23,24].