Primary bronchopulmonary amyloidosis

Primary bronchopulmonary amyloidosis is a primary disease characterized by amyloid deposition in the lung parenchyma, vessel walls, respiratory mucosa, pleura, mediastinal lymph nodes.

The reason, the pathogenesis of amyloidosis and its classification is set forth in the article " What provokes amyloidosis? ".

[1], [2], [3], [4], [5], [6], [7], [8], [9]

Pathomorphology of primary bronchopulmonary amyloidosis

The following clinical forms of primary amyloidosis of the bronchopulmonary system are distinguished:

• localized amyloidosis of the trachea, bronchi;
• diffuse amyloidosis of the trachea, bronchi;
• localized (solitary) amyloidosis of the lungs;
• diffuse alveolar-septal amyloidosis;
• amyloidosis of the pleura;
• amyloidosis of mediastinal lymph nodes;
• combined forms.

Amyloid deposits in the trachea and bronchi are multiple grayish-white smooth nodules up to 1 cm in diameter, while the entire wall of the bronchus can be infiltrated, which leads to its narrowing.

In the solitary form of pulmonary amyloidosis, there is one or more foci of amyloid deposits (pseudotumoral formations). This form is very rare. Diffuse amyloidosis of the lung is much more common. It is characterized by the deposition of amyloid in the interalveolar septa, around the capillaries, arteries, veins, as a result of their narrowing and desolation followed by the development of pulmonary hypertension and the formation of a chronic pulmonary heart. Amyloid complications in the bronchopulmonary system are detected using histochemical studies.

Symptoms of primary bronchopulmonary amyloidosis

Localized amyloidosis of the larynx, trachea and bronchi has the following characteristic clinical manifestations:

• superficial dry, often painful cough;
• often hemoptysis;
• hoarseness of voice;
• shortness of breath, wheezing;
• atelectasis of the corresponding part of the lung due to obstruction of the bronchus. Clinically, this is manifested by dulling of percussion sound with absence or sharp weakening of vesicular breathing, as well as recurrence of inflammation in the atelectasized area of the lung; it is accompanied by a cough with separation of purulent sputum;
• wheezing (due to narrowing of the affected bronchus).

Localized (solitary) deposits of amyloid in the lung parenchyma are not clinically manifested in any way (with a large amount of deposits, blunting of percussion sound is possible) and are diagnosed only radiologically.

Diffuse amyloidosis of the lungs is accompanied by the following symptoms:

• cough, unproductive or with the separation of mucous sputum, with the attachment of secondary infection in the bronchi - mucopurulent sputum;
• slowly but steadily progressing dyspnoea, first with exercise, then at rest;
• recurrent hemoptysis, usually moderately pronounced;
• pain in the chest, worse with breathing and coughing (with pleura involvement in the pathological process);
• difficulty in swallowing (with involvement of intrathoracic lymph nodes and compression of the esophagus);
• weakened vesicular breathing, may be listened to uninvited, non-sound crepitus mainly in the lower parts of the lungs. With damage to the bronchi and development of bronchial obstruction, dry whistling rales are heard;
• diffuse gray cyanosis (with development of severe respiratory failure);
• muffled heart tones, with the development of chronic pulmonary heart - accent of II tone on the pulmonary artery;
• tenderness in the right hypochondrium and enlargement of the liver - are observed with a decompensated pulmonary heart.

Laboratory data

1. The general analysis of a blood - essential changes are not present, the increase in an ESR, a thrombocytosis is sometimes defined. When the infectious-inflammatory processes join, leucocytosis appears with a shift of the leukocyte formula to the left.
2. The general analysis of urine - without deviations from the norm in most patients, sometimes there is a small proteinuria.
3. Biochemical blood analysis - characteristic of gammergamoglobulinemia, gipercholesterinemia, often there is an increase in the activity of aminotransferases, alkaline phosphatase, with a decompensated pulmonary heart and an increase in the liver, an increase in the level of bilirubin is possible.
4. Immunological studies often reduce the number of T-lymphocytes-suppressors, increase in B-lymphocytes, IgM and IgG immunoglobulins, and possibly the appearance of circulating immune complexes.

Instrumental research

1. X-ray examination of the lungs. Solitary amyloidosis of the lungs is manifested by rounded dimming with clear contours ranging from 1 to 5 cm in diameter. Salts of amyloidosis can be deposited in the foci of solitary amyloidosis, which is accompanied by a more intense shadow in the foci of compaction.

Diffuse amyloidosis of the bronchi is characterized by an intensification of the bronchial pattern in connection with the compaction of the walls of the bronchi. Diffusive amyloidosis of the lungs is manifested by augmentation of the pulmonary pattern or by diffuse fine-focal dimming.

In amyloidosis of the pleura, its thickening is noted; In amyloidosis of the intrathoracic lymph nodes, their enlargement is clearly visible, and they can sometimes become calcified.

2. Endoscopic examination of the trachea and bronchi reveals a characteristic pattern: edematous mucous membrane with coarse folds ("cobblestone pavement" pattern) with protruding yellowish papules. A biopsy of the mucous membrane allows us to clarify the diagnosis of amyloidosis.
3. Research of ventilating function of the lungs.

With amyloidosis of the trachea and bronchi, obstructive respiratory failure develops (decrease in FEV1), with diffuse amyloidosis of the lungs-a restrictive type (decreased GEL). The solitary amyloidosis of the lungs may not be manifested by disturbances in the ventilating function of the lungs.

4. ECG - with the development of pulmonary hypertension (with the diffuse form of lung amyloidosis) and the formation of a chronic pulmonary heart, there are signs of myocardial hypertrophy of the right atrium and right ventricle.
5. Investigation of biopsy specimens of bronchial, tracheal, and lung mucosa.

A biopsy of the mucosa of the trachea, bronchi, open or transbronchial lung biopsy is a reliable method of verification of the diagnosis. Amyloidosis is characterized by a sharply positive color with Congo red, and microscopy in polarized light reveals an amorphous substance with birefringent amyloid fibers of greenish color.

The prognosis for primary bronchopulmonary amyloidosis is considered relatively favorable, the life expectancy after diagnosis can be 30-40 years. The main complications are bronchopulmonary infectious and inflammatory diseases, respiratory failure, chronic pulmonary heart.

The examination program for primary bronchopulmonary amyloidosis

1. Common blood tests, urine tests.
2. Biochemical blood test: determination of the content of total protein, protein fractions, cholesterol, triglycerides, aminotransferases, alkaline phosphatase, bilirubin.
3. Immunological studies: determination of the content of B- and T-lymphocytes, subpopulations of T-lymphocytes, immunoglobulins, circulating immune complexes.
4. Radiography of the lungs.
5. Fibrobronchoscopy, tracheoscopy.
6. ECG.
7. Spirography.
8. Investigation of biopsies of the trachea, bronchi, lungs.