To implement a quality improvement plan aimed at achieving a 5% increase in the Forced expiratory volume in 1st second (FEV1) (% predicted value) in cystic fibrosis (CF) patients with impaired pulmonary function parameters over 12 months. Additionally, the plan aims to measure serum human epididymis protein 4 (HE4) levels in the studied subjects before and after pulmonary function improvement.

This study will be conducted on 35 children diagnosed with cystic fibrosis, aged between 6 and 18 years. Patients will be selected during their follow-up visits to the Pediatric Chest Clinic at Ain Shams University Hospital.

Inclusion Criteria:

A. Pediatric cystic fibrosis patients diagnosed based on the Consensus Guidelines from the Cystic Fibrosis Foundation, with a positive sweat chloride test (≥60 milliequivalent/L) and/or the presence of two cystic fibrosis disease-causing gene mutations.

B. Age ≥6 years. C. Forced expiratory volume in 1st second (FEV₁) ≤80%.

Exclusion Criteria:

A. Patients unable to perform spirometry.

All subjects in the study will undergo an interventional quality improvement plan.

A specialized clinic for CF patients will be established based on the quality improvement (QI) plan, where patients will be followed up every three months by a specialized multidisciplinary team, including a pediatric pulmonologist, pediatric nutrition consultant, pediatric gastroenterologist, chest physiotherapist, and pediatric endocrinologist.

Each specialized clinic will develop and implement standardized cystic fibrosis care algorithms and individualized treatment plans for each patient. These algorithms and plans will be continuously adjusted based on challenges encountered during follow-up to address barriers and deficiencies that may contribute to poor outcomes.

Areas needing improvement will be identified, and appropriate resources and strategies will be proposed. This will include the development of fishbone diagrams, flowcharts, Plan-Do-Study-Act (PDSA) cycles, PDSA ramps, and other quality improvement tools to address specific deficiencies. Additionally, training and engaging the team in quality improvement methodologies will be conducted.

Patients will undergo pulmonary function tests at baseline, followed by assessments at six months and one year during the study.

Inclusion Criteria:

• Pediatric CF patients diagnosed based on the Consensus Guidelines from the Cystic Fibrosis Foundation, with a positive sweat chloride test (≥60 milliequivalent/L) and/or the presence of two CF disease-causing gene mutations.
• Age ≥6 years.
• Forced expiratory volume in 1 second (FEV₁) ≤80%.

Exclusion Criteria:

●Patients are unable to perform spirometry.

This study will be conducted on 35 children diagnosed with cystic fibrosis, patients will be between the age of 6 years and 18 years old, and they will be selected during their follow-up visits to Pediatric Chest Clinic, Ain Shams University Hospital.