Contents
Interstitial pneumonia is an inflammatory lung disease that affects the alveoli, the porous connective tissue of the parenchyma.
This process is also called interstitial or idiopathic interstitial pneumonia. Inflammatory damage can be acute or chronic. Quite often, pneumonia causes the formation of exudate inside the lung cells, which leads to the replacement of the alveoli with fibrosis.
Interstitial lung inflammation is characterized by a severe clinical picture, which is often complicated by the rapid development of fibrosis or sclerosis of the alveolar tissue. Pneumonia of this type is often the cause of disability of patients, which significantly affects their daily life. Most often, interstitial pneumonia affects adults over the age of 40 years. This type of lung involvement is not common in young patients and children.
Classification of the disease
Interstitial pneumonia has acquired its own classification, as it is an independent group of interstitial lung diseases (ILD):
usual (ideopathic pulmonary fibrosis) is a pathology most often recorded in older men.
Nonspecific – is recorded more often in non-smoking patients, women, persons under 50 years of age.
Cryptogenic organizing – a pathology characterized by the proliferation of granulation tissues, which affects the lumen of the alveoli and bronchi.
Acute interstitial (diffuse alveolar damage).
Respiratory bronchiolitis – a disease that develops against the background of obstruction of the sections of the bronchial tree.
Desquamation– a pathology characterized by damage to the alveoli of the lungs with the formation of inflammatory exudate.
Lymphoid interstitial– episodically recorded pathology, which is characterized by the formation of lymphoid aggregates in the lung tissue.
Difference between interstitial pneumonia and ordinary pneumonia
With interstitial pneumonia, the alveoli degenerate into connective tissue cells. This process is influenced by the features of the clinical picture of the disease. Normal inflammation of the lungs does not cause deformation and specific damage to the alveoli.
Ordinary pneumonia is a disease of an infectious nature. Laboratory diagnostics allows you to verify the causative agent of ordinary pneumonia. With interstitial pneumonia, this is not possible.
Causes and risk factors
Currently, the underlying factors that cause the disease have not been established. Several theories of the development of pathology are considered, which are based on a disorder of the immune system. It is assumed that a certain factor penetrates the body, which triggers the mechanism for the production of antibodies.
It has been established that some infections can influence the development of interstitial pneumonia:
Mycoplasma.
Chlamydia.
Legionella.
Rickettsiosis.
Pneumococci.
respiratory viruses.
Cytomegalovirus.
Simple herpes.
From external factors, certain types of dust can be distinguished, which can lead to the progression of a pulmonary disorder.
The categories of persons who are included in the risk group are established:
Smokers or people who have smoked in the past.
People over 60.
Patients with HIV infection.
Patients with autoimmune disorders.
The formation of interstitial pneumonia is most often recorded against the background of some concomitant pathologies:
Rheumatoid arthritis.
Scleroderma.
Connective tissue diseases of combined etiology.
Asbestosis.
Radiation pulmonitis.
Chronic hypersensitivity pulmonitis.
Diabetes.
Drug-induced damage to the lung tissue
Genetic predisposition.
Who is the activator?
An infectious factor can be viruses, bacteria, fungi. Regardless of the type, the pathogen is not the root cause of the disease. The inflammatory reaction develops according to a typical scenario. If at the end of the classical inflammatory process the stage of tissue regeneration occurs, then in the case of interstitial pneumonia, the formation of connective tissue is observed. Why does it happen this way? The question is open to this day.
There is an opinion that the patient’s body undergoes some changes, as a result of which it regards its own cells as foreign.
clinical picture
The first manifestations of interstitial pneumonia do not differ from the symptoms of seasonal flu:
Sudden rise in body temperature.
Cough without discharge.
Dyspnea.
Respiratory disorders occur at first only with physical effort. Over time, shortness of breath is fixed at rest.
On the 1-2 day of the disease, patients voice complaints of pain in different parts of the chest, weakness, sleep disturbance, bouts of lack of air at night, loss of interest in food.
Within one to two weeks there is an increase in symptoms. The patient’s condition is aggravated. Respiratory failure may develop.
Symptoms may have some differences, which depend on the form of pathology. The interstitial lymphocytic form is characterized by:
Sluggish start.
Minor cough that worsens over time.
General fatigue.
Myalgia
Headache.
Dyspnea.
Sputum mixed with blood.
Respiratory failure progresses very quickly, against which primary pulmonary hypertension may appear. An increase in pressure in the pulmonary circulation provokes the formation of a cor pulmonale. With the help of hardware diagnostic methods in patients, an expansion of the right parts of the heart is recorded. This process can develop from 2 months to 2 years.
Manifestations of acute interstitial pneumonia (Hamman-Rich syndrome) are often combined with clinical signs of influenza, acute respiratory distress syndrome. The disease develops rapidly. Actively worsening respiratory failure is the cause of most deaths.
The first signs of the disease
Respiratory distress, shortness of breath.
Cough without discharge, which is not stopped by drugs.
Deterioration of the general condition.
Decreased body weight.
Transformation of the nail phalanges of the fingers according to the type of “drumsticks”.
These symptoms are characteristic of most patients with interstitial pneumonia. Perhaps the appearance of non-specific signs.
Changes in the structure of the lungs
Pathological mechanisms have a negative impact on the structure of the alveolar tissue. Changes at the level of cells depend on the form of the disease.
Form of the disease | Features of pulmonary changes |
idiopathic | In the lung tissue, fibrous areas resembling honeycombs are determined. Histological analysis shows fibroblasts, heterogeneous fibrous transformations |
Nonspecific | In the alveoli, inflammation, signs of fibrosis are fixed. Histology identifies fibroblast foci |
Organizing | The structure of the lungs is preserved. In the lower lobes, signs of a polypoid granulation texture are determined. |
Diffuse | The alveolar walls are thickened, the membranes have a hyaline structure |
Respiratory bronchiolitis | A slight fibrosis is fixed, fuzzy signs of inflammation |
disqualification | Almost the entire parenchyma is affected. Alveoli contain macrophages |
Lymphoid | Signs of lymphocytic sweating, the presence of lymphoid follicles are determined |
Diagnostics
Determining the correct diagnosis is possible only after a comprehensive examination of the patient, which includes:
General blood analysis.
X-ray examination of the chest in several projections.
High resolution CT.
The study of sputum in order to determine the type of cells, verification of the pathogen.
Bacterial culture of pleural effusion.
The pulmonologist carefully studies the patient’s complaints, clinical symptoms and images obtained as a result of hardware diagnostics.
During the examination, basal crepitus is determined, which eventually spreads to all lobes of the lungs. Hard breathing, wheezing (wet or dry) is fixed. A shorter sound is heard over the area of the altered lung tissue during percussion.
Breath tests, spirometry are necessary to specify respiratory disorders, fix changes in ventilation in the lungs.
The study of blood samples is necessary to exclude the development of bacterial inflammation, tuberculosis. Special deviations in the analysis, as a rule, cannot be identified.
X-rays show several features:
Spilled darkening of the lung tissue is determined on both sides.
Ground glass transformations.
Consolidation of inflammation.
Dense bronchial lining.
Signs of bronchiectasis.
Pronounced linear pulmonary pattern.
Fibrosis of the lung tissue leads to a decrease in the volume of the lower sections of the lungs.
Computed tomography determines the degree of spread of the disease, the stage of the clinical course. A biopsy of the lung tissue is necessary to establish the features of the histological structure.
Treatment of interstitial pneumonia
The success of therapeutic measures is due to the severity of the damage to the alveolar tissue, the prevalence of the process, the presence of concomitant pathologies.
A number of drugs are prescribed:
High doses of prednisolone for a long time – for the relief of inflammatory signs.
Cytostatics.
Azathioprine, cyclophosphamide, glucocorticosteroids are prescribed for established lymphoid form.
Colchicine, penicillins, interferon are additional drugs that enhance the effectiveness of the main ones.
Antifungal, antiviral or antibacterial pharmaceuticals are prescribed depending on the type of verified pathogen.
During the entire therapeutic period, oxygen support of the lungs is mandatory. Oxygen therapy facilitates the patient’s condition, allows you to perform physical activity, active movements.
Throughout life, patients are vaccinated against pneumococcal infections, influenza.