Pulmonary fibrosis: what it is, how it appears on X-ray, and why it is dangerous

The line "pulmonary fibrosis" in an X-ray report is rarely self-explanatory: behind it lies thickening of tissue deep in the lungs that changes breathing. Below is a calm breakdown of what this means, which examinations are used, and when a conversation with a doctor stops being a formality.

What pulmonary fibrosis and pneumosclerosis are

Pulmonary fibrosis is a condition in which tissue deep in the lungs scars over time: it becomes thicker and stiffer. Breathing through such tissue is harder, as if air were passing through a dense membrane, and the blood may not receive enough oxygen.

Such changes most often develop against the background of interstitial lung diseases — a large group of mostly chronic diseases in which the walls of the alveoli and small vessels become inflamed and scarred, and shortness of breath becomes the leading symptom. The term "pulmonary fibrosis" today is not fully equivalent to this concept, but it is still used in the same meaning. If the underlying cause of scarring is not identified, it is called idiopathic pulmonary fibrosis — a rare condition.

Causes of lung fibrosis

There are several causes, and they differ in nature. Inhalation of inorganic substances — silicosis, asbestosis, berylliosis; inhalation of organic substances — hypersensitivity pneumonitis, or exogenous allergic alveolitis. A separate group includes reactions to medications (antibiotics, chemotherapy agents, antiarrhythmics) and systemic connective tissue diseases: scleroderma, systemic lupus erythematosus, rheumatoid arthritis, dermatomyositis.

Among the infections after which lung tissue may scar are atypical pneumonia, COVID-19, pneumocystis pneumonia, and tuberculosis. Some cases are classified as idiopathic: sarcoidosis, idiopathic pulmonary fibrosis, histiocytosis X, alveolar proteinosis. Separately — prolonged inhalation of dust: metal, wood, asbestos; the risk is higher if a close family member has already had idiopathic fibrosis. But in most cases the underlying cause cannot be found.

Symptoms: when they appear and when they do not

A characteristic symptom is shortness of breath, which worsens with usual activities and in a lying position. The second characteristic symptom is a dry cough that does not go away; a clear threshold for talking to a doctor is three weeks or longer.

To this are added fatigue, weight loss without a clear cause, aching in the muscles and joints, and a change in the shape of the fingers, when the tips widen and become rounded and the nails curve. Idiopathic fibrosis is more common in people aged 70 and older, but sometimes begins earlier; symptoms usually increase slowly and worsen over time.

Pulmonary fibrosis on X-ray: what the doctor sees

Chest X-ray is the first step, but not the last: having seen signs of scarring, the doctor usually refers for high-resolution computed tomography, which shows lung tissue in more detail. In the diagnosis of interstitial diseases, clinicians rely on the clinical picture, radiological studies, pulmonary function tests, and laboratory data.

Among functional tests, spirometry is used — it shows how well the lungs work. If the picture remains unclear, fibrobronchoscopy and lung biopsy are used: small tissue samples are taken. The answer comes from the combination of the image, breathing tests, and examination, not from a single line in the report.

Possible complications and when to see a doctor

The disease progresses over time, but the rate varies from person to person. Over time, fibrosis can lead to chest infections, increased pressure in the vessels supplying the lungs (pulmonary hypertension), and heart failure, when the heart cannot cope with pumping blood. These conditions increase fatigue and shortness of breath and can reduce life expectancy.

• cough persists for three weeks or longer;
• shortness of breath worsens with usual activities or appears when the person lies down;
• constant fatigue;
• weight decreases without a clear cause;
• the fingertips have changed shape.

Pulmonary fibrosis by itself is not a reason to call an ambulance. The numbers 103 and 112 are for a life-threatening condition, for example with signs of heart attack or stroke.

This material is for reference: it helps to understand the report and prepare for a conversation with a doctor, but does not replace consultation and examination by a specialist.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer