Cystic Fibrosis

We've written about respiratory infections and other lung conditions before, but many of our previous topics have been about seasonal illnesses. Sicknesses like influenza are potentially dangerous, but mostly so in those with developing or compromised immune systems, like younger children or older adults. Cystic fibrosis, however, is difficult to manage regardless of your age. It's a progressive, genetic disease in which certain cells produce too many secretions, causing lung infections and breathing difficulty. CF requires specialized treatment plans and lifestyle management.

Cystic Fibrosis: The Numbers and Causes

Although considered a rare disease, cystic fibrosis is one of the most common of all life-limiting, recessive genetic diseases. It's the most common of these among people with European ancestry.

• More than 30,000 Americans have CF, and over 70,000 worldwide.
• Approximately 1,000 new cases of CF are diagnosed every year.
• 1 in 3,500 children born in America is diagnosed with cystic fibrosis.
• Over 75% of those with CF are diagnosed by age 2.
• Rates of cystic fibrosis are equal among men and women.

As a genetic disease, cystic fibrosis is inherited via a gene known as the cystic fibrosis transmembrane conductance regulator (CFTR). Mutations may cause the CFTR gene to be defective, and those with cystic fibrosis have inherited two copies of the gene, one from each parent. The American College of Obstetricians and Gynecologists recommends that any couples considering having a child get tested for CFTR mutations.

• There are 1,700 mutations in the CFTR gene.
• Standard carrier testing for CF screens the 23 most common mutations.
• 1 in 29 Causasian-Americans carry a CFTR gene mutation.
• 1 in 46 Hispanic-Americans carry a CFTR gene mutation.
• 1 in 65 African-Americans carry a CFTR gene mutation.
• 1 in 90 Asian-Americans carry a CFTR gene mutation.

Symptoms

Cystic fibrosis is a complex disease, and so it can have a wide variety of types and severity of symptoms, as well as complications.

The most common symptoms are:

• Build-up of thick, sticky mucus: epithelial cells lining the lungs and airways have a mutated protein that produces abnormally viscous mucus.
• Coughing and shortness of breath.
• Frequent chest infections.
• Salty-tasting skin.
• Poor growth.
• Poor weight gain with normal food intake.

Further symptoms or complications result from many factors, but particularly as a result of the mucus accumulation in airways. These cardiorespiratory complications result in about 80% of the deaths of patients in cystic fibrosis clinics in the U.S. They can include:

• Inflammation of the lungs and airways.
• Recurrent chest infections: pneumonia caused by excessive bacteria buildup in mucus.
• Recurrent sinus infections: caused by excessive mucus blocking sinuses.
• Decreased ability to exercise or stay active.
• Hemoptysis: coughing up blood.
• Pulmonary hypertension: high blood pressure in the lungs.
• Hypoxia: inadequate oxygen delivery through the body.
• Pneumothorax: collapsed lung caused by air leaking into the space between the lung and chest wall.
• Susceptibility to other lung diseases and bacterial infections.
• Changes in lung architecture: bronchiectasis, or enlargement of the lung airways.
• Heart failure.
• Respiratory failure.

These effects can cause chains of further complications. A lack of oxygen traveling through the tissue can lead to clubbing, a deformity of the fingers and toes. Mucus accumulation in the liver can block the bile duct and cause liver disease.

Excessive mucus production may not exist solely in the lungs and airways, but anywhere epithelial cells grow. It can build up in the pancreas and hinder nutrient absorption, inhibiting growth and weight gain. This is a particularly common symptom in infants, along with meconium ileus, a failure to pass fecal waste. Long-term damage to the pancreas can occur, leading to cystic fibrosis-related diabetes.

Most surprisingly, cystic fibrosis causes infertility in 97-98% of men with CF. This is usually due to a congenital absence of the vas deferens, the canal through which sperm travels. In addition, around 20% of women with CF have fertility issues stemming from thickened cervical mucus or malnutrition that disrupts ovulation.

Treating and Managing Cystic Fibrosis

Cystic fibrosis symptoms and their severity are widely varied between patients, so every patient will have an individualized treatment plan. Although most treatment plans will incorporate similar elements, they'll always have to account for the unique factors in each patient's condition.

Common therapies may include the following.

Airway Clearance: This consists of mechanical techniques or devices to loosen and thin the mucus built up in the lungs and airways in order to remove it. Sometimes this means something as simple as coughing techniques. Among more involved techniques are:

• Chest physiotherapy: Manual percussion of a patient's chest by a respiratory therapist to loosen mucus.
• Percussive devices: Such as vests that oscillate the chest wall with a compressor or mechanical ventilators that deliver bursts of air through a mouthpiece to thin and loosen mucus.
• Positive Expiratory Pressure (PEP): PEP devices utilize a mask or mouthpiece which creates pressure in the lungs, preventing the airways from closing and moving mucus into the larger airways to be expelled.

Inhaled Medicines: Liquid medications that open the airways and thin mucus, delivered through a nebulizer that turns them into a mist for inhalation.

Pancreatic Enzyme Supplements: These are capsules that help improve nutrient absorption, taken with meals.

Breathing Support: In advanced cases, CF patients may need to utilize oxygen tanks or machines to push air into their lungs, particularly while asleep.

Surgeries: In advanced cases, lung surgery may be necessary to remove sections of the lung too damaged by infection. Lung transplantation may also be an option.

Management

Due to earlier screening and improved treatment methods, patients with cystic fibrosis are likely to live well into adulthood. This is a marked improvement over the decades, when a half-century ago patients were unlikely to live past adolescence, or even infancy in many cases. Aside from respiratory treatments, lifestyle management can improve quality of life.

Fitness: Fitness plans with regular exercise can not only improve lung function, but strengthen bones and manage diabetes and heart disease.

Antibiotics: Due to increased susceptibility to infections, many CF patients are on regular antibiotics even when healthy.

Other Medications: CFTR modulators can target the specific defect in the CTFR protein, although these medications are meant for specific mutations.

Avoiding Germs: Increased emphasis on avoiding microorganisms may be necessary, including practicing proper hand-washing techniques and regularly disinfecting living spaces.