Association between glucose intolerance and bacterial colonisation in an adult population with cystic fibrosis, emergence of Stenotrophomonas maltophilia.

BACKGROUND: Diabetes is common in cystic fibrosis (CF). Glucose can be detected in the airway when the blood glucose is elevated, which favours bacterial growth. We investigated the relationship between dysglycemia and lung pathogens in CF.

METHODS: Cross-sectional and prospective analysis of CF patients (N=260) who underwent a 2h-oral glucose tolerance test. Clinical data was collected.

RESULTS: Stenotrophomonas maltophilia (S. maltophilia) was the sole bacteria increased in dysglycemic (AGT: 20.2%, CFRD: 21.6%) patients compared to normotolerants (NGT: 8.7%). S. maltophilia positive patients with dysglycemia had more pulmonary exacerbation events compared to NGTs (1.22 vs 0.63, P=0.003). The interaction between S. maltophilia colonisation and glucose tolerance status significantly increases the risk of lower lung function (P=0.003). Its growth was not affected by the evolution of the glucose tolerance after three years follow-up.

CONCLUSION: Prevalence of S. maltophilia was higher in dysglycemic patients, supporting the idea that S. maltophilia is a marker of disease severity in CF.