A Practical Approach to Glucose Abnormalities in Cystic Fibrosis

Abstract

Cystic fibrosis is a common genetic condition and abnormal glucose handling leading to cystic fibrosis-related diabetes (CFRD) is a frequent comorbidity. CFRD is mainly thought to be the result of progressive pancreatic damage resulting in beta cell dysfunction and loss of insulin secretion. Whilst Oral Glucose Tolerance Testing is still recommended for diagnosing CFRD, the relationship between glucose abnormalities and adverse outcomes in CF is complex and occurs at stages of dysglycaemia occurring prior to diagnosis of diabetes by World Health Organisation criteria. Insulin remains the mainstay of treatment of CF-related glucose abnormalities but the timing of insulin commencement, optimum insulin regime and targets of glycaemic control are not clear. These complexities are compounded by common issues with nutritional status, need for enteral feeding, steroid use and high disease burden on CF patients.

Cystic fibrosis related diabetes is not independently associated with increased Stenotrophomonas maltophilia infection: Longitudinal data from the UK CF Registry

“…Lehoux Dubois et al [7] noted increased S. maltophilia not only in those with CFRD based on the oral glucose tolerance test (OGTT) but also those with impaired glucose tolerance that did not meet the OGTT criteria. Therefore, those with early dysglycaemia (often characterised only by post-prandial glucose excursions and missed by OGTT) [18] may have increased prevalence of S. maltophilia but would not be classified as CFRD in the registry. Further work is required to understand the impact of early glucose abnormalities on S. maltophilia growth.…”

Pregnancy outcome in women with cystic fibrosis‐related diabetes

“…More generally, the absence of a more rapid decline of pulmonary and nutritional status in diabetic women could, at least in part, be related to the early identification and aggressive treatment of diabetes, which has reduced the negative impact of CFRD on CF clinical status (15). Another explanation could be that pregnancy is now well prepared for by CF women and care providers, leading to optimal preconception care and close monitoring of pulmonary exacerbations and nutritional status according to published guidelines (16).…”

Development of liquid culture media mimicking the conditions of sinuses and lungs in cystic fibrosis and health

“…Furthermore, they can be combined with host tissue to provide a physical scaffold for biofilm formation. 22 However, these models still lack key molecules of the lung, including host-derived antimicrobials, 23,24 polyamines 25,26 and a number of factors associated with CF comorbidities, including glucose, which is elevated in lungs in CF-related diabetes compared to healthy individuals, 27 and bile salts, which can be inhaled into lungs during CF-associated gastro-oesophageal reflux. 28 Most currently available in vitro and in vivo models focus on capturing conditions of the lung environment and therefore do not reflect the heterogeneity of the airways and are unsuitable for studying early infection processes that may take place in the sinuses.…”