Diabetes is a important complication of cystic fibrosis (CF). The improved life expectancy of patients with cystic fibrosis, as a result of advances in medical therapy, has resulted in an increasing prevalence of cystic fibrosis-related diabetes (CFRD). CFRD is associated with accelerated pulmonary decline and increased mortality. Pulmonary effects are seen some years before the diagnosis of CFRD implying that impaired glucose tolerance may be very early detrimental. Insulin treatment is clearly indicated in patients with CFRD to control symptoms and reduce complications. However, at the state of impaired glucose tolerance or fasting hyperglycaemia, current screening methods are not suitable for the early management of hyperglycaemia.The recent introduction of the continuous glucose monitoring system (CGMS), which provides a continuous glucose profile, has revealed to be clinically relevant in the investigation of glucose excursions over a long period. This device, widely use in diabetic non cystic fibrosis patients, has been validated in non diabetic cystic fibrosis subjects. Previous studies of continuous glucose monitoring have been realized in CF patients with normal glucose tolerance and diabetes and compared with non CF controlThe aim of our study is to evaluate the glucose profile with continuous glucose monitoring the nutritional and respiratory status in cystic fibrosis subjects, according to their glucose tolerance.

Inclusion Criteria:

• patients 10 years and older with cystic fibrosis
• not known diabetics with fasting blood glucose <1.26 g / l
• outside periods of exacerbation and / or glucocorticoid therapy
• affiliated to a social security scheme
• having received the results of the mandatory medical examination
• having signed an informed consent

Exclusion Criteria:

• Patient transplanted lung and / or liver
• Subject during participation in an interventional clinical trial
• unable to give informed about the information
• patient under judicial protection
• patient under tutorship or curatorship
• pregnancy
• breastfeeding
• patient treated with the combination lumacaftor and ivacaftor