^

Health

A
A
A

Disseminated pulmonary tuberculosis - Diagnosis

 
, medical expert
Last reviewed: 04.07.2025
 
Fact-checked
х

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.

We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.

If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.

X-ray diagnostics of disseminated pulmonary tuberculosis reveals the predominant syndrome of disseminated pulmonary tuberculosis - focal dissemination. Hematogenous and lymphohematogenous dissemination are characterized by multiple focal shadows, which are located in both lungs relatively symmetrically. In lymphogenous dissemination, focal shadows are often determined in one lung, mainly in the middle sections. Bilateral lymphogenous dissemination is usually asymmetric.

In acute miliary tuberculosis, it is impossible to detect focal dissemination in the lungs using radiography in the first 7-10 days of the disease. The density and size of fresh foci are insufficient for their visualization on a survey image. Characteristic features include a diffuse decrease in the transparency of the lung fields, blurring (blurring) of the pulmonary pattern, and the appearance of a peculiar fine-meshed mesh. On the 10th-14th day of the disease, radiography can reveal multiple small (no more than 2 mm in diameter) uniform foci that are symmetrically located from the apices to the basal parts of the lungs. Such total small-focal dissemination is a characteristic radiographic sign of miliary tuberculosis. Focal shadows have a rounded shape, low intensity, and unclear contours. They are often located in a chain, since they are localized along the course of the vessels. Small vessels are practically invisible against the background of a large number of foci - only large vascular trunks are clearly visualized.

Diagnosis of disseminated pulmonary tuberculosis using CT allows us to identify important signs of miliary lung lesions.

In young children, a feature of radiographs with acute disseminated tuberculosis is considered to be larger sizes of focal shadows than in adults: from 2 to 5 mm.

Subacute disseminated pulmonary tuberculosis, which develops with hematogenous dissemination of mycobacteria, is characterized by subtotal focal dissemination with predominant localization of focal shadows in the upper and middle sections of the lungs. Focal shadows are mainly large (5-10 mm), of low or medium intensity (subtotal large equifocal dissemination), usually with unclear contours. Some focal shadows merge and form focal darkening with areas of enlightenment caused by the disintegration of lung tissue. Sometimes destructive changes are represented by thin-walled ring-shaped shadows.

Subacute dissemination of lymphogenous origin is manifested mainly by unilateral focal shadows in the middle and lower parts of the lung. Focal shadows are located in groups among strip-shaped and reticular shadows of lymphangitis. Tomographic examination in the root of the lung and mediastinum often reveals significantly enlarged, compacted, sometimes partially calcified lymph nodes.

In chronic disseminated pulmonary tuberculosis, the changes on the radiograph are very diverse. A characteristic sign is considered to be subtotal or total, relatively symmetrical polymorphic focal dissemination. Multiple focal shadows have different sizes, shapes and intensities, which is due to the different time of their formation. In the upper and middle parts of the lungs, focal shadows are larger, there are significantly more of them than in the lower ones. There is no tendency for foci to merge. The symmetry of the changes may be disrupted as new rashes appear. In some patients, decay cavities are visible in both lungs in the form of thin-walled ring-shaped shadows with clear internal and external contours - this is how stamped, or spectacle, caverns look.

In the upper sections of both lungs, the pulmonary pattern is enhanced, deformed and has a reticular-cellular character due to pronounced interstitial fibrosis. Bilateral cortico-apical pleural layers (adhesions) are clearly visible. In the basal sections, the pulmonary pattern is depleted, the transparency of the lung tissue is increased due to vicarious emphysema. Due to fibrosis and a decrease in the volume of the upper lobes, the shadows of the roots of the lungs are symmetrically pulled up (the "weeping willow" symptom). The shadow of the heart on the radiograph has a median position ("drop heart"), and its transverse size in the area of large vessels is narrowed.

Timely diagnosis of disseminated pulmonary tuberculosis and effective treatment do not leave residual changes on radiographs. After subacute and chronic disseminated tuberculosis, radiographic examination usually allows to identify small and medium focal shadows of high intensity in both lungs - the "starry sky" symptom.

Slow progression of chronic disseminated tuberculosis often leads to the formation of a fibro-cavernous process.

trusted-source[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ], [ 8 ], [ 9 ], [ 10 ], [ 11 ]

You are reporting a typo in the following text:
Simply click the "Send typo report" button to complete the report. You can also include a comment.