Primary tuberculosis complex in the lungs

Primary tuberculosis complex in the lungs is a characteristic triad consisting of a focus of specific inflammation at the site of MBT introduction, lymphangitis and damage to regional lymph nodes. It is currently recognized that the classic primary tuberculosis complex with a pronounced pulmonary component, a large perifocal reaction develops in cases where such unfavorable circumstances as massiveness, virulence of tuberculosis infection and a decrease in the immunobiological capabilities of the macroorganism are combined. From the primary affect, the specific process spreads along the lymphatic pathways to the intrathoracic lymph nodes.

In case of alimentary penetration of the pathogen of both human and bovine types, the primary affect may be localized in the intestine. Localization of the primary affect in the skin, mucous membrane of the nose and middle ear, tonsils is casuistry.

In case of airborne infection, the primary tuberculosis complex most often develops in the lung tissue, according to A.I. Strukov, in 95% of cases. In this case, the peripheral (subpleural) sections are most often affected - mainly well-aerated segments (usually II and III segments of the right lung). Initially, several alveoli are involved in the process - alveolitis is formed, later - bronchioles, bronchiolitis occurs. Thus, the primary affect is always pneumonia. The size of the pneumonic focus depends on the number of alveoli involved in the process: with a small number, the focus of pneumonia can be the size of a millet grain, in other cases, pneumonia can be acinous, lobular and even lobar.

In the early stages of development, primary alveolitis has no specific features, but the early non-specific phase very quickly gives way to a specific one with the development of caseous necrosis. A fresh focus of primary tuberculous pneumonia is surrounded by a zone of perifocal inflammation due to toxic edema of the lung tissue. The pleura always takes part in the process, fibrin appears on its surface, and subsequently it is organized.

At the moment when MVT begin to spread through the lymph nodes, perifocal inflammation in the primary affect is already reduced, and the productive type of tissue reaction begins to prevail.

When a specific process penetrates into regional lymph nodes, nonspecific inflammation develops first. Following the exudative phase, necrosis develops very quickly, bypassing the development of tuberculous granulations. In some cases, this early necrosis can cover the entire lymph node. Since tuberculosis is characterized by a wave-like course, the primary complex usually has a multilayered morphological character: exudative changes, necrosis are replaced by a shaft of granulations, then exudation, necrosis, etc. occur again. The reverse development of the primary tuberculosis complex consists in the disappearance of the perifocal inflammation zone, the replacement of the exudative reaction with a productive one, and the development of encapsulation. The primary focus is well delimited from the surrounding lung tissue by a thick fibrous capsule, calcium salts are deposited in it, and in some cases, bone tissue is formed during the involution of the process. In the lymph nodes, the processes of reverse development occur much more slowly, but over time, hyalinosis of the capsule and calcification occur in them too.

The primary complex can develop in various age groups, most often in early childhood. Considering the fact that at present, along with the decrease in infection in children, there is a shift towards older age groups, the primary tuberculosis complex is also detected in adolescents.

Symptoms of primary tuberculosis complex

Symptoms of the primary tuberculosis complex are varied and depend on the severity of morphological changes at the time of examination of the child. Clinical symptoms depend on the size of the caseous lesion, mainly on the severity of the trifocal inflammation zone in the specific process of the intrathoracic lymph nodes.

Inflammatory changes in primary tuberculosis depend to a certain extent on the child's age. The tendency to extensive processes in the primary period is especially pronounced in children under 7 years of age. This circumstance is due to the fact that at this age the differentiation of the lung tissue is not yet complete, it retains wide lumens of lymphatic slits, loose connective septa, rich in lymphatic vessels, which contributes to the spread of inflammatory changes. Clinical manifestations of the primary tuberculosis complex in children in the younger age group are expressed to the greatest extent and are characterized by widespread and complicated forms.

Symptoms of primary tuberculosis complex

Diagnostics of primary tuberculosis complex

X-ray diagnostics of the primary tuberculosis complex is based on identifying its main components: primary tuberculous pneumonia, changes in the intrathoracic lymph nodes (usually regional) and the so-called pathway connecting them. The variability of local manifestations is due to the different length of the primary pulmonary lesion, its pathomorphological substrate (the ratio of caseous-exudative changes in the tissue reaction), the prevalence and nature of the process in the intrathoracic lymph nodes, as well as possible complications.

Radiologically, the shadow of primary tuberculous pneumonia during the active phase of the process is uniform, its contours are blurred, it is associated with the pathologically altered root with a "path" in the form of unclearly outlined linear formations. Their morphological substrate is the inflammatory transformation of the lymphatic pathways and interstitial tissue along the bronchi, vessels and lobes of the lung. The intensity of the shadow of the primary focus varies, which is due not only to its size, but also to the severity of caseous necrosis. Changes in the intrathoracic lymph nodes are often regional in nature. In this case, radiologically determines a volumetric increase or expansion of the root of the lung, a violation of the differentiation of its structural elements, in a delimited area in the affected area, blurring and blurring of the contours of the root is possible.

Diagnostics of primary tuberculosis complex

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