Tuberculous pleurisy
Pleuritis – it is an inflammation of the pleura, and it can be an independent form of tuberculosis, but in the majority of cases it develops as a consequence of pulmonary and extrapulmonary forms of the tubercular process.
Particularly frequent pleurisy is observed in patients with a disseminated form of tuberculosis of the lungs, it often complicates the course of the primary complex – bronchiadenitis.
In the case of idiopathic pleurisy, a focus of tuberculosis infection in the lungs is not possible to detect.
Nevertheless, a more detailed examination of the exudate reveals that in most cases, pleurisy has a tuberculous etiology.
Pathogenesis
Depending on the pathogenesis, they differ:
• Perifocal;
• Allergic pleurisy;
• Tuberculous pleurisy;
Perifocal pleurisy occurs by contact as a result of the spread of tuberculous inflammation of the visceral pleura with a subpleural focus.
Such pleurisy is also observed in tuberculosis of intrathoracic lymph nodes, since the latter are located in the mediastinum of the pleura.
Since both layers of the pleura are located close to each other, the pathological process spreads to the parietal layer of the pleura.
Allergic pleurisy develops in a sensitized organism, the focus of infection is most often the lymph nodes at the root of the lung, less often – in the lungs, bones, kidneys and other organs, and the predisposing factors are trauma or hypothermia on the chest.
It develops as a result of sensitization of the pleura, which causes the causative agent of tuberculosis or the products of its vital activity. The latter act as an antigen on which antibodies are formed and accumulate.
As a result of the antigen-antibody reaction, many biologically active substances are released, causing the increase in vascular permeability and the formation of an effusion.
In this way, damage to the vessels leads to the development of exudative pleurisy.
Tuberculosis of the pleura is a well-studied disease due to the widespread use of thoracoscopy.
In this case, tubercles appear on the pleura. Mycobacterium tuberculosis /MBT/ affects the pleura in the following ways:
1. Hematogenous route – in primary forms of tuberculosis and in disseminated tuberculosis in which there is bacteremia. Microbacteria enter the pleura through the bloodstream. In this case, tuberculosis of the pleura usually develops.
2. By lymphatic route – MBT penetrates the pleura through the retrograde flow of lymph, arising as a result of the pathological changes in the intrathoracic lymph nodes.
Such lymphatic changes block the normal flow of lymph and disrupt its drainage through the thoracic duct.
In this way, the causative agent of tuberculosis can penetrate into the pleura from the very deep part of the lung tissue.
Pathomorphology
Depending on the nature of the exudate, pleurisy is divided into dry /or fibrinous/ and exudative /or general inflammation/.
Fibrinous pleurisy can occur both as a result of perifocal inflammation and tuberculosis of the pleura. It is localized in a limited area of the pleura and is characterized by the absence of free fluid in the pleural cavity.
The pleural surface loses its luster. Subsequently, fibrin is deposited on the layers, especially on the parietal layer, due to which pleural adhesions are formed between the two sheets of the pleura.
Exudative pleurisy in tuberculosis, in turn, can be serous, serous-fibrinous and purulent. Hemorrhagic and chylous exudate is not characteristic of pleurisy with tuberculous etiology.
Hemorrhagic exudate can be present in cancerous pleurisy, and chylous in diseases of the blood.
Treatment of tuberculous pleurisy
Specific therapy is prescribed for the treatment of patients with dry pleurisy of tuberculous etiology.
Symptomatic drugs are also prescribed, reducing the sensitivity of the pleura during breathing, and in this way the patient’s condition is significantly alleviated.
