Cystic fibrosis

The cystic fibrosis gene on chromosome 7 is responsible for movement of salts such as sodium and chloride in and out of the cell. When the gene is abnormal sodium stays within the cell attracting fluid thus leaving less water or fluid outside the cell.

It is an autosomal recessive condition which means that in order to develop cystic fibrosis you need to inherit two cystic fibrosis genes, one from your mother and one from your father. If only one cystic fibrosis gene is inherited, you are called a carrier. About 1 in 25 people in the UK of Caucasian decent (white European) are carriers of the cystic fibrosis gene. It is much less common in Afro-Caribbean and Asian people. Carriers do not have the disease as they have one normal gene which can control the salt transport in their cells. But carriers can pass the cystic fibrosis gene on to their children.

Symptoms usually manifest in the first year of life and depend on the organ affected

Meconium ileus – Sometimes in the newborn the gut can become blocked with meconium - a thick, dark, sticky substance which is made by the baby's gut before being born. Urgent surgery may be needed to relieve the blockage. Lungs - Mucus is normally produced by the cells lining the airways, in cystic fibrosis the mucous is viscous and thicker than normal.

  • Cough and wheeze
  • Shortness of breath with breathing difficulties
  • Recurrent chest infections especially with pseudomonas aeruginosa and Burkholderia cepacia complex. They multiply in the thick mucus inside the lungs. The danger is that a person with cystic fibrosis who has such an infection can easily pass it on to another person with cystic fibrosis through close personal contact or by coughing near them. This is known as cross-infection. This can lead onto the bacteria becoming resistant to commonly used antibiotics which can be a problem treating them.
  • Pancreas – the pancreas secretes enzymes which are vital in the digestion of the food we consume. In cystic fibrosis the secretions are viscous and block the flow of digestive juices within the ducts of the pancreas. This can result in food not being digested or absorbed properly, in particular, fatty foods and fat-soluble vitamins (vitamins A, D, E and K).
  • Malnourishment leading to poor growth and poor weight gain
  • Large smelly, fatty, greasy stools due to fat malabsorption
  • Constipation
  • Bloated abdomen
  • Diabetic symptoms such as increased thirst, passing large amounts of urine, lethargy, tiredness – since insulin is secreted in the pancreas, blockage of pancreatic ducts lead on to diabetes. It is uncommon in children, but adults are at risk.
  • Pancreatitis – inflammation of the pancreas. Symptoms such as intense pain in the abdomen, nausea, vomiting etc.
  • Repeated sinus infections causing fever, headache, nasal discharge, localised tenderness over the sinuses.
  • Nasal polyps causing difficulty breathing, nasal bleeding and discomfort.
  • Rectal prolapse causing discomfort in the back passage, mild bleeding or staining of undergarments with blood.
  • Infertility – due to damage to the tubes carrying the sperms from the testis to the penis
  • Cirrhosis of the liver – causing, nausea, vomiting, jaundice, localised abdominal tenderness, abdominal distension due to ascites or fluid collection secondary to liver damage.
  • Osteoporosis (thinning of the bones) - due to defective absorption of vitamin D.
  • The sweat tastes very salty.


Due to defective absorption of nutrients, essential vitamins and repeated chest infections often causes under development in children, delayed maturation and sexual development in teenagers and generally poor health at any age.

Diagnosis

Sweat test – sodium chloride levels in the sweat are tested, which are abnormally high in cystic fibrosis.

Genetic testing – the cells from the inside of the cheek are scraped or a blood taken and tested for the abnormal gene. This test can confirm the diagnosis.

Screening test – all new born babies are screened for cystic fibrosis by testing blood taken by a heel prick and testing for immunoreactive trypsinogen which is abnormally high in cystic fibrosis.

Treatment

The management of cystic fibrosis is a multi-disciplinary approach, which means specialists from various fields such as paediatricians, physiotherapists, nutritionists, counsellors and child psychologists are involved.

Lung involvement

When lungs are involved regular chest physiotherapy and exercises are crucial. This helps to clear the airways of any thick mucus. It involves patting the chest with the child in a head down position which encourages the child to cough out any sputum or mucus. It's commonly practised twice a day.

Antibiotics are prescribed for any bacterial infection. Pseudomonas aeruginosa a bacterium persists in the thick mucus and might need stronger and bespoke antibiotic administered as an inhaler.

Anti fungals will be needed when a fungal infection is present which can be confirmed by sputum examination. Inhalers such as salbutamol are used to open up the airways.

Alpha dornase is a drug given by nebuliser in some cases which helps to break down the thick mucus into thinner mucus which can be easily coughed up, thus reducing the risks of any chest infections.

Oxygen Patients with advanced lung disease might benefit from oxygen.

Pancreatic involvement

When the pancreas are involved the enzymes secreted by the pancreas to digest food is vastly reduced. Hence pancreatic enzymes given orally will be needed. Vitamin supplements are also needed as their absorption will be compromised. A dietician's involvement is important as the diet can be tailored to the patients needs.

OTHER TREATMENTS

A range of other problems which are related to cystic fibrosis may develop in some cases and require treatment. For example:

  • Salt depletion may occur in hot weather and may require salt supplements.
  • Liver problems such as cirrhosis develop in some cases and may require specialist liver treatments.
  • When the pancreas is involved diabetes develops and usually requires insulin treatment.
  • Nasal polyps sometimes develop and can be treated with steroid nasal drops and sprays.
  • Constipation is quite common and may require regular laxatives.
  • Routine immunisations and annual flu jab are vital to prevent influenza. A pneumococcal vaccine helps to prevent pneumonia caused by pneumococcus aeruginosa.
  • In advanced cases lung or heart/lung transplantation may be offered as the lung disease becomes more severe.


Newer treatments

Gene therapy. This involves using an inhaled spray to deliver normal copies of the cystic fibrosis gene to the lungs.

Please consult the online doctor today for bespoke, evidence based and confidential medical advice.