The aim of this study to investigate and compare functional capacity with different tests and to evaluate the relationship between functional capacity and quality of life during acute pulmonary exacerbation in children with cystic fibrosis.

Exercise tests associated with prognostic values in CF patients and decreased exercise capacity has been correlated with a reduction in health-related quality of life. Pulmonary functions, functional capacity and quality of life will examine in this study.

This study will be participated children with cystic fibrosis who will diagnosed acute pulmonary exacerbation. Patients' pulmonary function test, functional capacity will be assess and record at hospital admission and hospital discharge and outpatient clinic control. Quality of life will be evaluated at only outpatient clinic control .

Pulmonary function test will be assessed with spirometry, functional capacity will be evaluated with 1-minute sit to stand test and 3-minute step test. And quality of life will be evaluated Cystic Fibrosis Questionnaire-Revised (CFQ-R).

Inclusion Criteria:

• Childrens with CF diagnosed between 7-18 years of age and hospitalized due to acute pulmonary exacerbation will be included in the study.The diagnosis of acute pulmonary exacerbation will be established by Fuchs criteria.

Exclusion Criteria:

• Patients with allergic bronchopulmonary aspergillosis (ABPA) who were treated with systemic steroid therapy and noninvasive mechanical ventilation support will not be included in the study.

Acute pulmonary exacerbation in childrens with cystic fibrosis diagnosed according to Fuchs criteria.