What Is Pulmonary Fibrosis?
The interstitial lung diseases, or ILDs, are a group of over 100 conditions that may result in lung inflammation and scarring. In the most severe form, this leads to Pulmonary Fibrosis (PF) a chronic condition characterised by shortness of breath. Pulmonary fibrosis is a condition in which the lung tissue becomes thickened, stiff and scarred over a period of time. The development of the scar tissue is called fibrosis. As the lung tissue becomes scarred and thicker, the lungs lose their ability to transfer oxygen into the bloodstream. As a result, the brain and other organs don’t get the oxygen they need. The scarring typically starts at the edges of the lungs and progresses towards the centre, making it more difficult to breathe.
What Are The Symptoms Of Pulmonary Fibrosis?
Symptoms of pulmonary fibrosis usually develop gradually and may not be noticed until the disease is well established. Because the disease may develop later in life, a common assumption is that the breathlessness is just part of middle age. If you feel breathless, you should see your doctor. Symptoms may include:
- Dry cough (can be chronic, dry, hacking coughing).
- Shortness of breath, especially during or after physical activity.
- Lasting tiredness.
- Weight loss.
- Bulb-like development of the fingertips and nails (a condition called clubbing).
What Causes Pulmonary Fibrosis?
In many cases, we can determine the disease or injury that caused PF, for example, exposure to feathers and dusts and some drugs may cause hypersensitivity pneumonitis and PF. However, the most common and severe form of PF has no known cause, and is called Idiopathic PF or IPF. IPF is a distinct disease that usually affects older patients. Although there are over 100 related ILDs, IPF is the most common.
‘Idiopathic’ means unknown and hence the cause of Idiopathic Pulmonary Fibrosis (IPF) is unknown. In some patients, the disease is genetic. Environmental factors (particularly exposure to certain types of dusts) may also play a role. What is known is that Pulmonary Fibrosis changes the lung’s ability to function normally. Typically, mild scarring of the lung tissue occurs first, but, over months and years, the normal lung tissue is replaced by more heavily scarred lung tissue, which makes it difficult to breathe and deliver needed oxygen to the body.
Even though the cause of IPF is still being investigated, the following are considered to be risk factors for disease development:
- Viral Infections.
- Exposure to dust / fumes and smoking.
- Age /gender (diagnosis is more common in men and older people).
- Acid reflux from the stomach into the lungs.
IPF affects each person differently and the disease progresses at varying rates. For some, the scarring occurs quickly, while in others, it happens over a longer period of time. Symptoms also vary from moderate to severe and may stay the same for a while.
How Is Pulmonary Fibrosis Diagnosed?
It is obviously very important when faced with a patient with PF to work out which of the 100 disease may be involved. The symptoms are similar to those of other diseases such as asthma, chronic obstructive pulmonary disease (COPD) and congestive heart failure. Additionally, pulmonary fibrosis can co-exist with these diseases.
Diagnosis of IPF can be difficult and, in order to confirm the diagnosis of IPF, doctors must rule out all known ILDs and therefore it will often take some time to explore and eliminate other possible diagnoses.
Confirming the diagnosis may involve one or more of the following tests:
- Blood tests to rule out other diseases.
- Pulmonary (lung) function tests to measure breathing capacity.
- X-ray and CT (“CAT”) scan of your chest to identify the pattern of scarring in your lungs.
- Lung cell sample by passing a small flexible telescope (a bronchoscope) down the breathing tubes in order to examine cells and look for signs of inflammation.
- Lung biopsy.
Sometimes, during examination of the lungs with a stethoscope, a doctor may hear crackling sounds in the chest. These crackles have a very characteristic sound. The chest X-ray may or may not be abnormal, but a high resolution CT scan will often show abnormalities. The classic findings in IPF show scarring of the lungs with small bubbles that have a characteristic appearance called “honeycomb” on the CT scan.
The lung function tests may show a reduction in the volume of the lungs and the transfer factor (or diffusing capacity) is a measure of the ability of the lungs to exchange gases (oxygen and carbon dioxide) into and out of the blood stream.
In many cases, the diagnosis of IPF can be made on CT scan but, in other cases of lung fibrosis, a lung biopsy may be necessary to obtain enough tissue to make an accurate diagnosis. The biopsy specimen is examined microscopically by a pathologist to confirm the presence of fibrosis. Often, a biopsy is not necessary.
Can Pulmonary Fibrosis Be Treated Or Prevented?
Some types of ILDs may respond to corticosteroids and other medications that suppress the body’s immune system by decreasing the processes that lead to fibrosis. The goal is to decrease lung inflammation and subsequent scarring.
At this point, there is no cure for IPF, which is why Breathing Matters is supporting UCL Respiratory research.
The treatment options are limited since scarring appears to be permanent once it has developed. Lung transplantation is one of the few options available. There are two therapies that are approved by National Institute of Clinical Excellent (NICE) and are available for NHS-England patients with moderately severe IPF as assessed by lung function. Both drugs are similarly effective in reducing the rate at which the lungs scar. However, the side effects of either treatment can be serious and a lung specialist is required to determine what treatment is appropriate.
Further information on the drugs available to treat IPF can be found here
Pulmonary fibrosis causes decreased oxygen levels in the blood which can lead to a condition known as pulmonary hypertension, and patients with pulmonary fibrosis are frequently treated with supplemental oxygen to prevent heart failure.
In addition to the medicines, there are also non-drug approaches available that can help manage pulmonary fibrosis symptoms. Pulmonary rehabilitation, often combined with oxygen therapy, may help improve the ability to function without severe breathlessness.
Pulmonary rehabilitation involves nutritional advice, exercise and breathing techniques, whilst oxygen therapy allows the patient to continue being as active as possible.
Living With Pulmonary Fibrosis
Please consult your doctor before making changes to your lifestyle.
- Quit smoking to help increase oxygen levels in your blood and lower blood pressure and heart rate.
- Eat less saturated fat and more fruits and vegetables.
- Exercise to help keep your body working as efficiently as possible.
- Lose excess weight to help improve your breathing capacity.
- Avoid situations in which you might catch infections from others.
- Avoid excessive pollutants and dust.
- Try to stay mentally active.
- Seek emotional support through family, friends, healthcare providers and support groups.
- Don’t over exert yourself and ensure you get enough rest.
Our fantastic research team at the Centre for Inflammation and Tissue Repair (CITR) at UCL Respiratory aims to find better ways to diagnose, treat, and ultimately find a cure for pulmonary fibrosis. The research is both clinical, involving patients, and laboratory based.
The Current Clinical Trials we are involved in includes:
- Investigation of matrix regulation in chronic lung disease: Chronic respiratory disease are characterised by lung scarring or fibrosis. This work investigates the development of scar tissue in disease as diverse as pulmonary fibrosis, asthma and tuberculosis. By understanding the mechanisms that underlie the scarring process, we can help to develop drugs to overcome it.
- Autoantibodies and pulmonary fibrosis: Studying the role of auto-antibodies (antibodies that the body makes against its own organs) in pulmonary fibrosis. In particular, we are developing ways to looking for auto-antibodies that attack patients’ own blood vessels in patients with interstital lung diseases including IPF and rheumatoid arthritis associated ILD.
- Molecular imaging studies to investigate mechanisms, prognosis and response to therapy in interstitial lung disease: Investigating the ability of special scans, called PET scans, to light up active areas of lung fibrosis to help us decide on treatment courses.
- Circulating white blood cells: We have shown that a specific type of circulating white blood cells, called neutrophils, are different in patients with IPF and can help us predict which patients will do less well than others. We are trying to find out more about why this happens and whether the abnormal neutrophils are the result of, or the cause of, the lung disease.
- Activation of white blood cells in the lung: We have shown that white blood cells are activated in the lungs of patients with pulmonary fibrosis and are carrying out studies to find out what causes this activation and whether it can be reversed. In particular, we are investigating the effect of low oxygen concentration on white cell activation in IPF and other diseases.
- Airway epithelial project: We are able to look at the interactions of white cells and the lung epithelium and compare the white cells from patients with pulmonary fibrosis to those from control patients with no lung disease. We are particularly interested in how the mucin Muc5B (that gives sputum it’s ‘stringy’ quality might influence these interactions. We are also looking at whether genetic material from the lung can be detected in blood of patients with IPF allowing a test for earlier diagnosis, and to measure response to novel treatments.
- Platelets and pulmonary fibrosis: Investigating the role of platelets in IPF and other ILDs. We have studies looking at whether platelets accumulate in the lungs of patients with lung fibrosis, and whether platelets are abnormally ‘sticky’ in these patients. Our results are hopefully going to be published later this year.
- The anticoagulation in IPF study: For many years, it has been recognised that patients with IPF are at increased risk of blood clots. We are looking at whether patients derive benefits from taking drugs that ‘thin’ the blood to prevent clots. We are completing a study this year and hope to publish the results and apply for a bigger study.
- The INHALE study: Investigating whether new drugs for pulmonary fibrosis can be delivered directly to the lungs via inhalation and therefore avoiding toxic side-effects.
- Novel imaging: We are looking at machines learning to teach computers to read CT scans in lung diseases, such as IPF and sarcoid. This will allow us to be more accurate in comparing scans between patients and in the same patient, over time or with treatment.
- Novel treatments: In collaboration with industry, we are taking part in three studies of novel agents in IPF, and one novel way of measuring response to treatment in sarcoidosis.
For further guidelines, please refer to the British Lung Foundation.