Pulmonary Fibrosis vs. Cystic Fibrosis: What Are the Differences?

You may be confused by the terms "pulmonary fibrosis" and "cystic fibrosis" because they sound similar. However, these are two different health conditions with different causes, symptoms, treatments, and more.

Pulmonary fibrosis is lung scarring that usually occurs in older age from unknown or environmental causes. Cystic fibrosis is a genetic condition that a person is born with that causes thickened mucus in the lungs, intestines, pancreas, kidneys, and liver.

In this article, learn more about the similarities and differences between pulmonary and cystic fibrosis.

Symptoms

Both pulmonary fibrosis and cystic fibrosis affect the lungs and result in breathing difficulties. However, they affect the lungs differently (scarring vs. mucus production, respectively), so even some breathing symptoms may differ. Cystic fibrosis also affects more organ systems than pulmonary fibrosis, so it has a wider variety of symptoms.

Pulmonary Fibrosis

Symptoms of pulmonary fibrosis include:

• Shallow breathing
• Shortness of breath
• Chronic dry cough
• Fatigue
• Weight loss
• Finger clubbing (changes to the soft tissue around the fingernails and toenails)

Cystic Fibrosis

Symptoms of cystic fibrosis include:

• Wheezing
• Chronic wet cough
• Frequent lung or sinus infections
• Salty skin
• Meconium ileus (bowel obstruction causing a thicker and stickier than normal first stool in an infant)
• Slow or stunted growth
• Weight loss

Read More: Symptoms of Cystic Fibrosis

Causes

The causes of pulmonary fibrosis and cystic fibrosis are different. However, there is a genetic component to each.

Pulmonary Fibrosis

The cause of pulmonary fibrosis is largely unknown. This is called idiopathic pulmonary fibrosis (no identifiable cause).

Certain inherited genes can increase the risk for pulmonary fibrosis; however, this is rare and the inheritance pattern is not well understood. Not everyone with these genes goes on to develop pulmonary fibrosis and not everyone with pulmonary fibrosis has these genes, implying other environmental risk factors are at play.

Risk factors for pulmonary fibrosis include:

• Age
• Sex (people assigned male at birth have a higher risk)
• Underlying health conditions (e.g., diabetes)
• A history of tobacco use
• Environmental exposures

Read More: Causes and Risk Factors of Pulmonary Fibrosis

Cystic Fibrosis

Cystic fibrosis is caused by genetics. It is an autosomal recessive condition. People with cystic fibrosis must have inherited two copies of a mutated cystic fibrosis transmembrane receptor (CFTR) gene, one from each parent.

There are over 2,500 identified CFTR mutations. Mutations of this gene lead to issues with mucus production and other symptoms seen with cystic fibrosis.

Read More: Causes of Cystic Fibrosis

Diagnosis

Pulmonary fibrosis and cystic fibrosis are diagnosed in different ways. They are diagnosed at other times, too. Cystic fibrosis is usually diagnosed either before birth or during infancy or childhood. Pulmonary fibrosis, however, is primarily diagnosed in older adults.

Pulmonary Fibrosis

It can be challenging to diagnose pulmonary fibrosis because its symptoms can appear like other, common conditions, such as a cold or chronic obstructive pulmonary disease (COPD).

First, your healthcare provider will ask you about your medical history and perform a physical exam, including auscultation (listening to your lung sounds). They may also perform blood tests, chest X-rays, and computed tomography (CT) scans to rule out other conditions. These images may also show signs of scarring that are indicative of pulmonary fibrosis.

Your healthcare provider may order a bronchoscopy (a procedure that involves inserting a narrow tube with a camera through the trachea to look at your airways) or a lung biopsy (a laparoscopic surgical procedure to get a sample of lung tissue). If your provider identifies any lung scarring and rules out other conditions, they will likely diagnose you with pulmonary fibrosis.

Cystic Fibrosis

Genetic testing has a significant role in diagnosing cystic fibrosis. Parents can be screened to see if they carry the CFTR genes. Prenatal genetic testing can also show if a fetus will have cystic fibrosis. Additionally, in the United States, all states require newborn genetic testing for cystic fibrosis.

Sometimes, a healthcare provider may not have identified cystic fibrosis at birth. A sweat chloride test can also diagnose cystic fibrosis. This short, pain-free test measures chloride levels in a person's sweat and has a 98% accuracy rate. Your provider may combine a sweat chloride test with genetic testing to confirm a diagnosis.

Read More: How Cystic Fibrosis is Diagnosed

Treatment

There is no cure for cystic fibrosis and pulmonary fibrosis. It is vital to have a correct diagnosis because treatments vary and can improve the quality of life and life expectancy for both conditions.

However, the two conditions are not usually mistaken for each other because of the difference in symptoms and age at which they develop.

Pulmonary Fibrosis

Treatment for pulmonary fibrosis can improve the quality of life. Treatments include:

• Medications: Two drugs are approved by the Food and Drug Administration (FDA) to treat pulmonary fibrosis. They are Ofev (nintedanib) and Esbriet (pirfenidone). They are both antifibrotic agents and can slow down lung scarring. Certain steroid medications may also be prescribed to reduce inflammation.
• Oxygen therapy: Many people with pulmonary fibrosis use supplemental oxygen at some point. They may use this constantly, intermittently, or only during sleep or certain activities.
• Pulmonary rehabilitation: This therapeutic program involves education on pulmonary fibrosis, how to conserve your energy, how to move, and appropriate exercises. It may be led by physical therapists, occupational therapists, nurses, respiratory therapists, or a combination of clinicians.
• Lung transplant: Some people with pulmonary fibrosis may be eligible for a lung transplant, replacing permanently scarred lung(s) with healthy lungs. However, this is a major surgery, not everyone is a candidate, and you must accept the associated risks and follow-up therapy.

Read More: Research Advances in Idiopathic Pulmonary Fibrosis

Cystic Fibrosis

Early treatment for cystic fibrosis is essential and prolongs life expectancy. Treatments for cystic fibrosis include:

• Medications: Prescription medications are a mainstay of cystic fibrosis treatment. The main medication categories include bronchodilators, mucolytics, antibiotics, and CFTR modulators.
• Airway clearance techniques: These are techniques to dislodge mucus from blocking airways. They may be performed by the person with cystic fibrosis, a caregiver, or an assistive device.
• Exercise: Keeping active with meaningful exercise or therapist-prescribed exercises can help maintain lung function.
• High-calorie diet: A high-fat, high-calorie diet is recommended to maintain a healthy weight with cystic fibrosis. A registered dietitian can educate and assist you in developing an appropriate diet.
• Surgery: Sometimes, your healthcare provider may recommend surgery depending on cystic fibrosis complications. These include nose or sinus surgery, bowel or blockage surgery, and lung or liver transplant.

Read More: How Cystic Fibrosis is Treated

Prevention

It is impossible to prevent cystic fibrosis because it is a genetic, inherited condition that is present at birth. However, parents can undergo genetic counseling and screening to determine their risk of conceiving a child with cystic fibrosis.

For pulmonary fibrosis, there are more options for prevention, although these are somewhat unclear because, in most cases, the cause of pulmonary fibrosis is unknown. Quitting smoking or never smoking and reducing occupational exposure to fumes and smoke can reduce your risk of pulmonary fibrosis.

Summary

Cystic fibrosis and pulmonary fibrosis are different conditions. Pulmonary fibrosis is scarring on the lungs. It usually affects older people, and the causes are unknown, although smoking and exposure to some fumes are risk factors. Cystic fibrosis is an abnormal production of mucus involving the respiratory and digestive systems. It is genetic; people are born with it and are diagnosed at birth or in childhood.

A Word From Verywell

Despite the similarities in their names, pulmonary fibrosis and cystic fibrosis are quite different conditions. One commonality between the two is that they are incurable conditions that affect a person's quality of life. If you or someone you are caring for is having trouble breathing, coughing, wheezing, or not acting like their usual self, it is important to talk to a trusted healthcare provider about your concerns.