Cystic fibrosis presentation in del. F508 and p. Tyr109Glyfs compound heterozygote CFTR state: a case report

The diagnosis of cystic fibrosis (CF) is commonly confirmed by molecular genetics with the presence of specific mutations of cystic fibrosis transmembrane conductance regulator (CFTR) gene. We report a case of cystic fibrosis (CF) in a 15-year-old female patient who is a compound heterozygote for CFTR gene, with delta F508 and Tyr109Glyfs mutations detected. This is the first detailed description of such a case in the medical literature. The primary CF presentation occurred at the age of 9 in the form of gastrointestinal symptoms including greasy, bulky, and foul-smelling stool. The patient exhibited delayed growth, with her height and weight being below the 5th centile for age according to the World Health Organization growth curves. Pancreatic enzyme supplement treatment was started immediately, alongside high-fat and high-calorie diet, resulting in patient's recovery and development. DNA analysis of CFTR gene demonstrated the presence of del. F508 mutation and a rare combining deletion and insertion mutation p. Tyr109Glyfs. The combination of the two mutations is very rare in CF patients and is therefore valuable to document this case in order to provide information on disease progression, therapy options, and outcomes. With standard treatment and early diagnosis, the patient is currently doing well and is not restricted by the disease in her daily and sports activities.