Diagnostics of the primary tuberculosis complex
Last reviewed: 23.04.2024
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X-ray diagnostics
X-ray diagnosis of the primary tuberculosis complex is based on the identification of its main components: primary tubercular pneumonia, changes in the intrathoracic lymph nodes (often regional) and the so-called pathway that connects them. The variability of local manifestations is due to the different length of the primary pulmonary focus, its pathomorphological substrate (the ratio of caseous-exudative changes in the tissue response), the prevalence and character of the process in the hilar lymph nodes, and possible complications.
Radiographically, the shadow of primary tuberculosis pneumonia in the period of the active phase of the process is uniform, its contours are blurred, it is associated with a pathologically altered root "path" in the form of fuzzy outlined linear formations. Their morphological substrate is inflammatory transformation of lymphatic and interstitial tissue along the course of bronchi, vessels and lobules of the lung. The intensity of the shadow of the primary focus is different, which is due not only to its magnitude, but also to the severity of caseous necrosis. Changes in the intrathoracic lymph nodes are more often regional. In this case, roentgenologically determine the volume increase or expansion of the lung root, the violation of the differentiation of its structural elements, on the borderline in the affected area, blurriness, blurriness of the root contours is possible.
Tomographic examination of the mediastinum allows documenting the enlargement of the lymph nodes with their hyperplasia to a size exceeding the cross section of the adjacent vascular trunk, with perinodular inflammation and partial calcification. In addition to the involvement of the intrathoracic lymph nodes, in the basal zone, the phenomena of lymphostasis and lymphangiitis are determined in the form of changes in the pulmonary pattern on the side of the lesion. The figure is displayed in a greater number of elements, deformed in a fine-meshed and linear type with blurred contours. Practical observations in accordance with the literature data indicate the inconsistency of this feature. Manifestations of lymphangitis and lymphostasis in tuberculosis in infants are noted in the first 2 months in the acute course of the process in the intrathoracic lymph nodes.
Differential diagnostics. The radiological picture of changes in specific and nonspecific inflammatory processes in children is extremely similar. Differential diagnosis in part of the observations can be made by comparing the analysis of the complex of clinical-radiological, laboratory, bronchoscopic and other data. Primary tuberculosis complex in the phase of infiltration with primary affect, which is a specific segmentum or lobit, must be differentiated from nonspecific processes of the same extent. If there are destructive changes in the pulmonary component, it becomes necessary to carry out differential diagnosis with staphylococcal pneumonia, an abscess of the lung, and less often - with suppurating cysts.
Segmental segmental pneumonia has become quite common in modern conditions. The reverse development of such processes can be delayed up to 3-8 months from the onset of the disease. Prolonged segmental nonspecific pneumonia - reversible processes, as inflammatory changes in later terms can be eliminated.
Primary tuberculosis complex in children in modern conditions due to a number of factors contributing to the increase in the reactivity of the child's organism, and also under the influence of intensive tuberculostatic therapy can have a smooth accelerated course. In this regard, protracted segmental pneumonia and the primary tuberculosis complex may have a similar clinical and radiological picture. In both diseases, low symptomatic manifestations, similar segmental localization, involvement of the intrathoracic lymph nodes are noted. In this regard, it is necessary to highlight the distinctive features that can be used for differential diagnosis of these processes.
To diagnose the primary tuberculosis complex, the following basic criteria should be followed.
- Analysis of sensitivity to tuberculin in the dynamics in patients with tuberculosis allows you to establish infection, while in most cases diagnose an early period of infection - a turn. In most patients with pneumonia, susceptibility to tuberculosis indicates a postvaccinal allergy, and some children react negatively to tuberculin. However, it should be borne in mind that in some cases a child infected with tuberculosis can tolerate a nonspecific protracted bronchopulmonary process. It is in children infected with tuberculosis that differential diagnosis should be carried out to exclude the possible development of tuberculosis. The emergence of segmental and lobar lesions in a child during the period of the bending of tuberculin reactions in the absence of a previous ARI indicates rather a specific infection.
- The primary tuberculosis complex is characterized by a gradual onset of the disease, the symptoms of intoxication and respiratory failure are less pronounced. With the radiological-determined share, segmental process of tuberculosis etiology, even with a significant increase in body temperature, the child's relatively good health is noted, it remains active, respiratory disorders are not very pronounced. Comparison of clinical manifestations of the primary tuberculosis complex and pneumonia reveals the predominance of general symptoms in tuberculosis, while pneumonia is more pronounced cough, pain in the chest, a small amount of sputum may be separated. In the physical examination of a child with a primary complex, percussion changes are expressed, they predominate over the auscultative data. A child with a prolonged segmental pneumonia is characterized by an acute onset. In the clinical picture of the acute period of segmental pneumonia, a correspondence is noted between the severity of the condition, the prevalence of the process and the age of the child. In shared polysegmentary processes in infants, the severity of intoxication syndrome, respiratory symptoms, and severe condition are revealed. With pneumonia, auscultative changes predominate-differently moist wet rales on the background of weakened, sometimes bronchial breathing.
- In tubercular lesions, the upper sections of the pulmonary tissue most often suffer, the focus is subpleural (segments I-III), characterized by unilateral lesions, more often the right lung. In nonspecific processes, polysegmentary lesions are prevalent with predominant localization in the lower lobes of the lung, simultaneous combination of lesions of segments of two or more lobes and bilateral changes. Streptococcal and staphylococcal pneumonia also differ in multifocus, bilateral spread, the variability of the radiographic pattern in a short time. There is a triad of characteristic symptoms: infiltration foci, rounded cavity decay, pleural exudate.
- A bronchoscopic examination of a patient with tuberculosis is characterized by localized nonspecific catarrhal endobronchitis or (more rarely) tuberculous bronchitis. In patients with pneumonia, widespread, diffuse, usually bilateral puffiness and flushing of the mucous membrane are noted, in the lumen of the bronchi - a mucopurulent secret.
- In difficult cases for the purpose of differential diagnosis, antibiotic therapy is performed with a wide spectrum of action, taking into account bacterial sensitivity.
Given the pathomorphism of primary tuberculosis in children in modern conditions and the change in clinical manifestations, each case of lung injury and protracted disease requires the vigilance of pediatricians of general practice and the need for an earlier consultation of a phthisiatrician.