Cystic Fibrosis

Cystic Fibrosis is a chronic disorder of the exocrine glands, which is the most common genetic disease in whites. Exocrine glands are structures present throughout the body whose function is to produce and secrete vital secretions to help other organ systems to perform their physiological roles. Examples of such secretions are digestive juices, sweat, saliva, tears, milk, etc.
Cystic fibrosis involves multiple organ systems but mainly results in chronic respiratory infections, pancreatic enzymes insufficiency, and associated complications in untreated patients. End-stage lung disease is the leading cause of death. Most patients are diagnosed on newborn screening or at the age of 6-8 months; two-thirds of patients are diagnosed by one year of age.

Cystic Fibrosis is an autosomal recessive disease caused by a mutation in the CFTR gene (chloride gland dysfunction) on chromosome 7 and involvement of exocrine gland dysfunction. Problems in the chloride channel transport of water and ions result in thick or sticky secretions in the respiratory tract, gastrointestinal tract, pancreas, sweat glands, and other exocrine tissues. It is difficult to clear thick secretions, which results in clogging causing symptoms.

Cystic fibrosis is the most common deadly hereditary disease in the white population in the United States. It is common worldwide, with the highest incidence found among people of Northern European ancestry. There is a high carrier rate, also being one in 25 people. If both parents are carriers, 1 in 4 children can have the disease. It is least prevalent in Africans and Asians.

The history of cystic fibrosis in a family is the most important risk factor. You are at higher risk of cystic fibrosis if any of your family members are suffering from it, like a parent, a sibling, or a cousin, and also if any or both of your parents carry the mutated CFTR gene.

Signs and symptoms depend upon the organ system involved.

RESPIRATORY TRACT SYMPTOMS

• The patient presents with recurrent respiratory infections, chronic cough, wheezing (whistling sound) in less than one year.
• Chest pain
• Bluish discoloration of the skin and mucous membrane called cyanosis.
• Clubbing (changes in the areas under and around the toenails and fingernails).
• Recurrent Pneumonia
• Asthma
• Hemoptysis (blood in the sputum).
• Shortness of breath on exertion.
• Recurrent sinusitis.
• Nasal polyposis ( soft, non-cancerous growths on the lining of your nose or sinuses).

GASTROINTESTINAL TRACT SYMPTOMS

• The most common presentation is a newborn with obstructed small intestine with abnormally thick meconium (earliest stool).
• Severe abdominal distension and pain.
• Failure to pass meconium.
• Bilious vomiting (vomit contains bile which is dark green to yellowish-brown fluid produced by the liver).
• Ileocecal Intussusception; a serious condition in which one part of the intestine slides into the next part.
• Rectal prolapse; a condition when the lowest part of the large intestine slips outside the anus.
• Deficiency of fat-soluble vitamins and malabsorption of carbohydrates, proteins,  and fats occur due to Pancreatic insufficiency may present with night blindness, neuropathy, and Rickets ( softening and weakening of bones in children).
• Frequent, large, bulky,  foul-smelling, greasy stools that  float in water called  Steatorrhea
• The patient may present with jaundice or gastrointestinal bleeding due to involvement of the liver
• Scarring of the liver called cirrhosis

UROGENITAL TRACT SYMPTOMS
     •    Undescended Testicle; a condition when the testicle is not moved to the scrotum.
     •    Male infertility
     •    Amenorrhea (absence of menstruation) may occur in females with severe nutritional deficiency.

      Other symptoms include Type 2 Diabetes Mellitus, salty-tasting skin,

A patient’s history is obtained, and a doctor performs a physical examination to diagnose cystic fibrosis. Diagnosis is based on typical lung and gastrointestinal symptoms, family history, and a positive sweat chloride test. A more salty sweat than usual and the respiratory and gastrointestinal symptoms present confirm the diagnosis.

Genetic testing

• Genetic testing is offered to couples before conception to identify the carrier state.
• Antenatal screening: Chorionic villous sampling at 10weeks – for parents with an affected child already or where both parents are positive on karyotyping.

Other supportive tests for the organs system affected are;

• Pulmonary function test.
• Bronchoalveolar lavage and sputum microbiology.
• Contrast Barium Enema.
• Radiography ( chest, abdomen, sinus).

Some other diseases may have the same symptoms.

• Acute sinusitis
• Bronchiolitis
• Pediatric asthma
• Pediatric celiac disease (sprue)
• Pediatric Bronchiectasis
• Primary ciliary dyskinesis
• Short stature

A comprehensive care approach must be followed to improve quality of life and render a person independent and symptoms-free. Mild acute pulmonary exacerbations can be treated successfully at home with the help of the following measures.

• Increasing the frequency of airway clearance.
• Inhaled bronchodilators treatment.
• Chest physical therapy and postural drainage.
• Increasing the dose of a mucolytic drug, Dornase alpha ( Pulmozyme)
• Use of oral antibiotics.

Treatment for complications

• Nasal polyp; surgical removal
• Persistent and chronic sinusitis; surgery
• Intussusception (surgery is indicated if a child has peritoneal signs).
• Gastrostomy tube placement for supplemental feeding.
• Rectal Prolapse; surgery
• Lung transplantation is indicated for end-stage lung disease

Your doctor may prescribe you the following medications.

• Pancreatic enzyme supplements.
• Multivitamins (including fat-soluble vitamins A, D, E, and K).
• Mucolytics (to clear the airway).
• Bronchodilaters ( salbutamol).
• Nebulized, inhaled, oral or intravenous Antibiotics(Fluoroquinolones).
• Anti-inflammatory drugs.
• Drugs to treat associated disease or complications(e.g., insulin, biphosphonates).
• Drugs (e.g: Ivacaftar,lumacaftar/ivacaftar,tezacaftar) which potentially reverse the abnormalities in chloride transport.

Cystic fibrosis disease is incurable. The treatment can provide only symptomatic relief. The median survival age for a person suffering from cystic fibrosis is around 37 years. However, advances in the research domain for medical and surgical treatment have improved the survival rates over the last decades and made it possible to live until the age of 40.

Cystic fibrosis is incurable but adopting the following lifestyle changes helps people cope with the illness.

• Regular exercise
• Stay hydrated, especially before exercise.
• Chest physiotherapy.
• Stay vaccinated
• Maintain a good nutritional state, e.g., pre-meal oral pancreatic enzymes.
• Eating a healthy diet includes high calories, high fiber, good protein, and fat-soluble vitamins.
• Regular follow-ups with your healthcare provider.

Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 16, 2023.

References

Cystic Fibrosis - What Is Cystic Fibrosis? | NHLBI, NIH

https://www.nhlbi.nih.gov/health/cystic-fibrosis

Cystic fibrosis in the year 2020: A disease with a new face - De Boeck - 2020 - Acta Paediatrica - Wiley Online Library

https://onlinelibrary.wiley.com/doi/abs/10.1111/apa.15155