Cystic fibrosis-related diabetes mellitus (CFRD), a major complication of CF, is present in 2% of children, 19% of adolescents, and 40%–50% of adult CF patients.314 The development of diabetes is independently associated with CFTR.315 However, CFRD is not an autoimmune disease similar to T1D.316 The occurrence of macrovascular complications and consequent death is extremely low. This evidence concerns the gene CFTR and cystic fibrosis-related diabetes.