Early Dysglycemia Detected by Continuous Glucose Monitoring in a 6-Year-Old Child with Cystic Fibrosis: A Case Report

Background: Cystic fibrosis–related diabetes (CFRD) screening is typically recommended from age 10, yet glucose abnormalities may emerge earlier. Conventional screening tools may fail to detect dysglycemia in young children with cystic fibrosis (CF). Case Presentation: A 6-year-old girl with CF and severe pancreatic insufficiency underwent 14-day continuous glucose monitoring (CGM) as part of an observational study on glucose metabolism in pediatric CF patients. Results: CGM detected marked glycemic variability (38.4%), a mean glucose level of 192 mg/dL, and a time in range of 56%, despite only mildly elevated fasting glucose values. Laboratory workup confirmed CFRD (glycated hemoglobin 8.8%). After insulin initiation, pulmonary function improved substantially, with forced expiratory volume increasing from 76% to 97% of predicted within 2 months. Conclusions: CGM may identify clinically significant dysglycemia in young children with CF who would otherwise go undetected by age-based screening. In selected high-risk pediatric CF patients below the standard screening age, CGM may enable earlier diagnosis and timely intervention—a clinical question that warrants prospective investigation. © 2026, © The Author(s)