Cystic fibrosis–related diabetes

Cystic Fibrosis-Related Diabetes (CFRD) is a unique type of diabetes that is found in individuals with Cystic Fibrosis (CF). CFRD is considered the most common complication of CF, affecting approximately 20% of adolescents and 40-50% of adults with the disease. Unlike other forms of diabetes, CFRD presents a mix of features from both Type 1 diabetes and Type 2 diabetes, making its management particularly challenging.

Pathophysiology

The pathophysiology of CFRD is complex and not entirely understood. It involves both insulin deficiency due to the destruction of the pancreas and insulin resistance. In CF, thick mucus blocks the ducts of the pancreas, preventing the release of insulin and leading to chronic inflammation and fibrosis. This damage to the pancreas results in decreased insulin production, characteristic of Type 1 diabetes. Additionally, the chronic inflammation seen in CF can lead to insulin resistance, a hallmark of Type 2 diabetes.

Diagnosis

Diagnosis of CFRD can be challenging as the symptoms can be subtle and may overlap with those of CF itself. The Oral Glucose Tolerance Test (OGTT) is considered the gold standard for diagnosing CFRD. According to the Cystic Fibrosis Foundation guidelines, it is recommended that all individuals with CF undergo annual screening for CFRD starting by age 10.

Symptoms

Symptoms of CFRD may include, but are not limited to, unexplained weight loss, increased thirst, increased urination, and fatigue. These symptoms often mimic those of classic diabetes but can be overlooked in CF patients due to the overlap with symptoms of their underlying lung disease.

Treatment

The treatment of CFRD focuses on maintaining optimal blood glucose levels without compromising nutritional status, which is crucial in CF management. Insulin therapy is the cornerstone of CFRD treatment, as oral diabetes medications are often ineffective due to the unique pathophysiology of the disease. Nutritional management also plays a critical role, with a focus on maintaining a high-calorie diet to counteract the malabsorption and increased energy needs associated with CF.

Impact on Cystic Fibrosis

The development of CFRD has significant implications for individuals with CF. Research has shown that CFRD is associated with a decline in lung function, increased frequency of pulmonary exacerbations, and reduced survival. Therefore, early detection and aggressive management of CFRD are essential to improve outcomes in CF patients.

Conclusion

CFRD is a complex condition requiring a multidisciplinary approach for its management. Ongoing research is essential to better understand the pathophysiology of CFRD and to develop more effective treatments. Early diagnosis and comprehensive management are key to improving the quality of life and prognosis for individuals with CFRD.

NIH genetic and rare disease info

• NIH info on Cystic fibrosis–related diabetes

Cystic fibrosis–related diabetes is a rare disease.