Cystic Fibrosis: A major advance in the scientific studies for the molecular mechanisms, symptoms and treatments
The sweat test generally considers concentrations of 60mEq/L and above as significant enough to confirm the patient’s disease, however, further tests may be necessary. False positives are a controversial topic and so most countries do not test for cystic fibrosis in new born babies.
Despite cystic fibrosis mainly effecting exocrine function, it does have some implications for endocrine glands. Endocrine glands do not use ducts, unlike exocrine glands, and therefore secretions are directed into the bloodstream. Affected endocrine glands impair the secretion of hormones. For example, there have been cases of diabetes related to cystic fibrosis. Damaged islets of Langerhans in the pancreas cannot secrete insulin sufficiently hindering the maintenance of optimum blood glucose levels.
Mucus build-up increases vulnerability to bacterial infection like Pseudomonas aeruginosa colonies forming. Ultimately, antibiotic treatment becomes difficult as bacterial colonies construct a biofilm. Biofilm is a matrix of slime that protects the bacteria from antibiotics and the immune system. As the inflammatory response is stimulated by infection, the extent to which tissue is damaged and lung scarring is a significant indication for diagnosis. Chronic bacterial infection and inflammation can lead to bronchiectasis which is airway wall damage. Wall damage causes permanent dilation of the bronchi. Sometimes, if the inflammation erodes into a blood vessel this can cause hemoptysis; the coughing up of blood.
Pancreatic damage can cause acute and chronic pancreatitis. Poor growth and in severe cases; malnutrition, occurs as sufferers lack the ability to digest food effectively. This is because of the absence of the required digestive enzymes. Digestive enzymes and hormones are not secreted due to cyst formation blocking liver and pancreatic ducts. If the pancreas cannot secrete digestive enzymes into the duodenum, the body cannot extract essential nutrients. With pancreatic insufficiency, proteins and fats are not absorbed, which can lead to steatorrhea. Steatorrhea is the excretion of fat-containing stools in faeces.
Meconium ileus is a bowel obstruction that occurs in infants with cystic fibrosis. The bowel obstruction is caused by meconium being abnormally thick and sticky, consequently blocking the ileum in the small intestine. Subsequently, bowel movement strain induces rectal prolapse. This is a surgical emergency that needs to be attended to immediately.
Above 95% of males are infertile because of cystic fibrosis. Vas deferens which would normally connect the testes and ejaculatory ducts in males may be blocked or non-existent, making them unqualified to use intercourse to conceive a child. Moreover, fertility problems for females arise due to obstructed cervices. A woman may also face complications with their ovulation cycle because of malnutrition. However, most females with cystic fibrosis do not have problems conceiving.
Although the disease is currently incurable, symptoms can be alleviated by various treatments. Pharmalogical drugs can activate other ion channels to transport chloride ions to replace the role of CFTR. Personalised treatments have been designed, such as lumacaftor.
Lumacaftor is a target specific CFTR mutation type that acts as a chaperone that brings the mutated ion imbalance caused by faulty CFTR channels can be tackled by the use of a solution called hypertonic saline.