CYSTIC FIBROSIS. causes, symptoms and treatment

cystic fibrosis

1. CYSTIC FIBROSIS

2. INTRODUCTION Cystic fibrosis (CF) is a disease of exocrine gland function that involves multiple organ systems but chiefly results in chronic respiratory infections, pancreatic enzyme insufficiency, and associated complications in untreated patients. Pulmonary involvement occurs in 90% of patients surviving the neonatal period. End-stage lung disease is the principal cause of death .

3. PATHOPHYSIOLOGY Cystic fibrosis is caused by defects in the cystic fibrosis gene, which codes for a protein transmembrane conductance regulator ( CFTR ) that functions as a chloride channel and is regulated by cyclic adenosine monophosphate ( cAMP ). Mutations in the  CFTR  gene result in abnormalities of cAMP -regulated chloride transport across epithelial cells on mucosal surfaces.

4. Defective CFTR results in decreased secretion of chloride and increased reabsorption of sodium and water across epithelial cells. The resultant reduced height of epithelial lining fluid and decreased hydration of mucus results in mucus that is stickier to bacteria, which promotes infection and inflammation. Secretions in the respiratory tract, pancreas, GI tract, sweat glands, and other exocrine tissues have increased viscosity, which makes them difficult to clear.

5. SIGNS AND SYMPTOMS GIT Meconium ileus Abdominal distention Intestinal obstruction Increased frequency of stools Failure to thrive (despite adequate appetite) Recurrent abdominal pain GI bleeding Jaundice

6. RESPIRATORY Cough Recurrent wheezing Recurrent pneumonia Atypical asthma Dyspnea on exertion Chest pain

7. GENITOURINARY TRACT Undescended testicles or hydrocele Delayed secondary sexual development Amenorrhea

8. Physical signs depend on the degree of involvement of various organs and the progression of disease, as follows: Nose – Rhinitis, nasal polyps Pulmonary system – Tachypnea, respiratory distress with retractions, wheeze or crackles, cough (dry or productive of mucoid or purulent sputum), increased anteroposterior chest diameter, clubbing, cyanosis, hyperresonant chest on percussion GI tract – Abdominal distention, hepatosplenomegaly , rectal prolapse, dry skin, cheilosis

9. DIAGNOSIS Sweat Test:- The quantitative pilocarpine intophoresis sweat reveals elevated sodium and chloride level more than 60meq/L Early diagnosis can be achieved by neonatal screening and amniocentesis

10. MANAGEMENT 1/ Postural drainage and chest physiotherapy for clearance of airways. 2/ Inhaled recombinant human Dnase :- to reduce sputum viscosity. 3/ Antibiotics 4/ Inhaled broncodilators 5/ Inhaled corticosteroids 6/ Vaccination

11. Refrences : Davidson’s Medscape