- Diseases, Disorders & Conditions
What You Should Know About Cystic Fibrosis
Essentially, cystic fibrosis may be described as an autosomal recessive disease that is caused by defects in the cystic fibrosis trans-membrane conductance regulator (CFTR) gene. When functioning normally, the gene is involved in encoding for a protein that functions as a chloride channel in addition to the regulation of the flow of ions across the apical surface of the epithelial cells.
Mutations of the gene cause abnormalities of camp- regulated chloride transport across the epithelial cells of the mucosal surfaces. As a result of the failure to conduct chloride by the epithelial cells associated with the transport of water, there are abnormalities that result in viscid secretions in the respiratory tract, sweat glands, the gastrointestinal tract as well as other exocrine tissues. As a result of increased viscosity of the secretions, it becomes difficult to clear them. However, how the disease affects an individual is largely dependent on the mutation of the gene. Although cystic fibrosis may affect multiple organ systems, it typically results in chronic respiratory infections, insufficiency of pancreatic enzyme as well as other associated complications among the untreated patients.
The mutations of the CFTR gene bring about abnormalities in camp- regulated chloride transport across the epithelial cells on the mucosal surfaces. Some of the main defects that result from the mutations of this gene include;
- The complete absence of CFTR protein synthesis,
- A defective maturation of the protein as well s early degeneration - this is caused by the mutation (δf508), which has been shown to be one of the most common mutations,
- Disordered regulation - this is where ATP binding is diminished as well as diminished hydrolysis,
- Defective conductance of chloride/ channel gating,
- Diminished transcription as a result of promoter/splicing abnormalities,
- Accelerated channel turnover from the cell surface,
As a result of the defective CFTR, there is reduced secretion of chloride as well as an increased re-absorption of sodium and water across the epithelial cells. This results in a reduced height of the epithelial lining fluid as well as decreased hydration of the mucus, which in turn results in mucus that is stickier to bacteria. This promotes infection and inflammation.
The manifestation of cystic fibrosis has been shown to be high changeable, appearing in neonatal period as well as later in life. With some of the patients, the condition is highly asymptomatic for several years. Some of the most common clinical sign of cystic fibrosis include chronic cough, chronic diarrhea as well as malnutrition. Although these are just a few of the major clinical signs, it can appear in various other ways, affecting multiple systems and organs. One of the other most common symptoms that affect the digestive tract is exocrine pancreatic insufficiency. This is typically characterized by chronic diarrhea with the presence of undigested foods. There is also decreased secretion of sodium bicarbonate, which tends to reduce the efficacy of pancreatic enzymes as well as the precipitation of bile salts, which also causes increased acidic pH in the duodenum, resulting in malabsoption.
Poor digestion of fats, proteins and carbohydrates is also observed, these being as a result of the obstruction of pancreatic canauli by the mucous plugs.
For people with cystic fibrosis, malabsorption is caused by pre- epithelial dysfunction. This tends to occur following the rejection of non- hydrolysable nutrients in the lumen. Malnutrition results from inadequate digestion of foods as well as increased energy needs, which among these patients is rarely achieved. On the other hand, diabetes among cystic fibrosis patients is as a result of micro-vascular and other macro-vascular complications that are typically linked to accelerated lung deterioration, which ultimately cause increased death rates. Some of the other common signs include;
- Low levels of one or more fat- soluble vitamins,
- Vitamin deficiency,
- Meconium ileus - this is the obstruction of the terminal ileum by a thick meconium. It is the first signal of pancreatic insufficiency affecting about 15 percent of basis.
- Patients with gastrointestinal symptoms will exhibit nausea and vomiting among other symptoms such as indigestion,
- Eosinophilic esophagitis (EOE) among patients between 4 and 15 years old,
For patients with massive haematemesis from esophageal varices, it becomes necessary to revert to the basis of airway, breathing and circulation (ABC). Protecting the airway in this case may call for intubation using esophageal balloon tamponade through the use of a Sengstaken-Blakemore Tube. Although intubation maybe necessary, there is still a debate as to whether or not patients with cystic fibrosis should be intubated and ventilated.
Management and outcome
Complex and multi-systemic involvement of cystic fibrosis treatment and follow up are essential in specialty centers (cystic fibrosis) with multidisciplinary care teams. During the initial confirmation, a patient has to undergo baseline assessment, investigations as well as initial therapy. This is in addition to patient/caretaker education, which includes counseling and instructions concerning techniques used for airway clearance as well as the proper use of equipment.
Treating cystic fibrosis aims to:
- To maintain lung function as close to normal as possible by controlling respiratory infection as well as clearing mucus from the airways,
- Administering nutritional therapy - this involves the use of enzyme supplements, multivitamins as well as mineral supplements in order to maintain adequate growth,
- Management of complications,
At home, mild acute pulmonary exacerbation maybe treated using a number of measures that involve;
- Increasing the frequency of airway clearance,
- Using oral antibiotics such as fluroquinolones,
- Increasing the dose of mucolytic agent dornase alfa,
- Chest physical therapy and postural drainage,
- Inhaled bronchodilator treatment,
For the patients with cystic fibrosis, medications used for treatment include; mucolytics, bronchodilators, anti- inflammatory agents, pancreatic enzyme supplements, multivitamins as well as the agents that are devised to potentially reverse abnormalities in chloride transport. According to the pulmonary therapies committee of cystic fibrosis foundation, a long term use of hypertonic saline for patients aged 6 and older is recommended for the purposes of improving functions of the lungs as well as reducing the number of exacerbation. Following treatment using drugs like ivacattor and mannitol, Follow up is meant to determine how treatment is helping the patient or the next course of action. Given that this is a problem of gene mutation, management is necessary to ensure that the patient's symptoms are treated for improved health. Treatment is therefore used to treat gastrointestinal diseases, reduce accumulation of mucus, treat pancreatic disease and hepatonility disease and increase the level of pancreatic enzymes to normal.