Cystic Fibrosis

Cystic Fibrosis

1. CAUSE

   • Genetic condition
     • Causes CFTR gene on chromosome 7 to not work properly
       • Different errors can occur in this gene which causes different severities of the condition
       • Results in cells of effected organs being unable to control levels of sodium and chloride
         • Too much sodium/chloride ions inside cells causes water to follow, leaving too little water outside of the cells
         • Causes mucus outside of cells to be too thick
     • Autosomal recessive inheritance
       • Two carriers have a 25% chance of a CF baby, 50% chance of a carrier baby, and 25% chance of an unaffected baby
     • 1 in 2,500 babies born with CF in the UK
     • 1 in 25 people of Caucasian descent in the UK carry the gene

2. HOW DOES IT AFFECT THE BODY

   • LUNGS
     • Mucus in airways is too thick/sticky
       • Bacteria becomes trapped in lungs causing infection
         • Frequent lung infections cause inceased coughing and wheezing, breathlessness, and increased mucus production
           • Infection can be so serious that CF patients commonly recieve IVABs several times a year
           • Restricted lung function due to narrowed aiways caused by damage, and airway obstruction caused by mucus
             • Lung fuction may reduce to 30% lower than normal lungs, in which case a lung transplant may be considered
     • Cilia lining the airways do not work properly due to being clogged with thick mucus
     • Cross-infection
       • Typically harmless bacteria can be harmful to CF patients if they colonise in lungs e.g. Psuedomonas aeruginosa
       • Personal contact between CF patients poses a high risk for transmission of harmful bacteria
   • DIGESTIVE SYSTEM
     • Pancreas cannot deliver digestive enzymes due to duct being blocked by thick mucus
       • These enzymes build up in the pancreas and cause inflammation
         • This causes pancreatic insufficiency as the prancreas is unable to support digestion
           • Poor digestion can cause symptoms such as greasy stools, constipation, nausea, swollen abdomen, loss of appetite
           • People with CF require a higher daily calorie intake and more fatty foods to compensate for their depressed digestive system
     • CF related diabetes can occur from a lack of inssulin production
   • BONES
     • Osteopenia and osteoporosis - low bone mineral density (BMD)
       • Severe lung disease, low body weight, a lack of exercise and ineffective uptake of vitamins can cause this
     • Joint pain e.g. Arthritis
   • Higher concentration of salt in sweat
   • Delayed puberty and infertility
   • Nasal polyps and sinusitis
   • Clubbing of fingers

3. DIAGNOSIS

   • Carrier testing for indivudals with a family history of CF
   • Newborn screening - heel prick test
     • This tests for the most common mutations, but not all, so rare genetic mutations of CF may not be diagnosed until later life
   • Sweat test

4. TREATMENT

   • MEDICAITON
     • Antibiotics to prevent chest infections
     • Bronchodilators to widen airways and ease breathing
     • Steriods to reduce airway inflammation and treat nasal polyps
     • Mucolytics to break down mucus
       • DNase
   • DIET
     • High fat/calorie/ protein diet
     • Enzyme supplements to aid digestion
       • Creon - pancreatic enzyme replacement therpay
   • PHYSIOTHERAPY
     • Physical exercise
     • Airway clearance techniques
       • ACBT - deep breathing, huffing, coughing, relaxed breathing
   • LUNG TRANSPLANT
     • Considered when lung function is significantly reduced
     • Can greatly improve length and quality of life
       • Does not provide 'normal' life expectancy
         • Approx. 50% will survive for at least 5 years, many people living for at least 10 years post-transplant
     • Carries risk
       • Rejection
     • Does not cure CF