Miliary pulmonary tuberculosis is a generalized form of tuberculosis infection, characterized by damage to the surface of the lungs, as well as the appearance of a small tuberculate rash.
Miliary tuberculosis mainly affects the capillaries. After the capillary walls die, Mycobacterium tuberculosis spreads into the connective tissue and forms tubercles. The tubercles are small in size (1-2 mm) and symmetrical in shape.
The constant formation of tubercles and the entry of mycobacteria into the blood provokes acute intoxication of the body. Foci of miliary tuberculosis can be located not only in the lungs, but also in other organs.
Causes and mechanism of development
Miliary tuberculosis is caused by the bacterium Mycobacterium tuberculosis. Penetrating into the respiratory tract of a healthy person, it forms numerous tuberous rashes in the lungs. As the disease progresses against the background of severe intoxication and immune damage, necrosis of the capillary walls occurs, followed by cessation of their functioning. This creates the prerequisites for the mycobacterium M. tuberculosis to enter the blood.
The acute course of miliary tuberculosis leads to massive hematogenous dissemination of the pathogen throughout the body, affecting a large number of systems. This development mechanism is typical for the primary form of the disease.
However, when M. tuberculosis enters the blood of a healthy person, it does not always lead to acute miliary tuberculosis. For this to happen, a significant reduction in the body's resistance is necessary with a simultaneous increase in the immune response of the lung tissue. Such conditions are created in the following cases:
- early childhood;
- lack of BCG vaccination;
- a history of HIV infection;
- malnutrition;
- antisocial living conditions;
- frequent hypothermia;
- during periods of hormonal imbalance in the body.
The risk of developing disseminated tuberculosis increases markedly with chronic pathologies of the respiratory tract, malignant lesions of the blood and other organs, diabetes mellitus, and chronic renal failure with the need for constant hemodialysis. The risk of infection is especially high for people who are in constant contact with tuberculosis patients.
Destructive variants of the disease
The reduction in destructive forms of the disease (fibrous-cavernous and cavernous tuberculosis) was one of the undoubted achievements of Soviet medicine. Unfortunately, from the beginning of the 90s of the last century, these forms began to attack again. Since then, “Life has become better, life has become more fun,” but since not everyone and not everywhere, there has been no progress in the fight against pulmonary destruction.
- The culprits for this are primary drug resistance of Koch's bacillus, insufficient organization of anti-tuberculosis care in certain regions, and unabated migration flows.
- The bulk of the population today lives in cities. Most manufacturing enterprises and transport are also concentrated near the place of permanent residence and work of the average person. In such conditions, our body is practically a filter element for all inhaled carcinogens and harmful substances from urban air.
- The next, but no less significant factor is the low quality of food. Many have heard about GOST standards that existed in the USSR and strict quality control in the food industry of the Soviet era. As many have already seen in practice, beautiful labels and GOST names on modern packaging do not guarantee anything other than the obvious desire to find demand for their products.
- A separate line worth mentioning is the high stress load that not only drivers and teachers experience.
All of these factors, even individually, can cause serious harm to health.
- The low level of immune defense does not allow patients to actively resist destructive changes, and the massive breakdown of tissue determines the high degree of release of mycobacteria into the outside world by such patients.
- Phthisiatricians classify destructive tuberculosis as a qualitatively different form of the disease, which develops against the background of immunodeficiency. Often this development is so rapid that it manages to fit within the gap between two fluorographic examinations of the lungs. It is more correct to regard it not as advanced tuberculosis, but as its peculiar course, in which the lung tissue falls apart with the formation of decay cavities (cavities). This process is characterized by chest pain, shortness of breath, cough, hemoptysis and pulmonary hemorrhage.
- In prognostic terms, the lower the number of cavities and the smaller they are, the more favorable the outcome and the higher the patient’s chances.
Routes of infection
The leading route of transmission of miliary pulmonary tuberculosis is airborne. The bacterium M. tuberculosis is incredibly resilient and can be spread more than 90 cm to one side when someone with active tuberculosis coughs, sneezes or talks.
With low immunity, infection can occur through nutritional or household contact. There are known cases of pathogen penetration through the connective membrane of the eye and wounds on the skin, which is more typical for weakened, malnourished children.
Thus, the route of transmission of infection is largely determined by the resistance of the organism. Moreover, it is not at all necessary that a person infected from a patient with the miliary form will suffer from the same type of pulmonary tuberculosis. He may experience damage of any location and type. It all depends on the complex of provoking factors that developed at the time of infection and the body’s immune response.
Classification and symptoms
Depending on the clinical picture and complexity of the course, four forms of miliary tuberculosis are distinguished:
- meningeal;
- pulmonary;
- typhoid;
- acute miliary sepsis.
Meningeal miliary tuberculosis
Meningeal miliary tuberculosis is more common in adult patients. In this form of the disease, the meninges are affected, which is expressed by severe headaches, nausea, photophobia and intolerance to loud sounds, and indifference to the environment.
If disseminated tuberculosis develops as meningoencephalitis, the patient progresses to paresis and paralysis. Facial, oculomotor, and spinal nerves may be affected. In the latter case, dysfunction of the pelvic organs sphincters occurs, which is manifested by spontaneous separation of urine and feces.
Pulmonary miliary tuberculosis
The pulmonary form of miliary tuberculosis occurs with primary damage to the respiratory system. The patient experiences pronounced respiratory symptoms:
- coughing;
- dyspnea;
- increased body temperature;
- respiratory depression, cyanosis.
A faint noise is heard in the lungs, the pulse quickens, and the heart rhythm is disturbed. Chest pain may occur.
Typhoid miliary tuberculosis
The typhoid (abdominal) form of miliary tuberculosis begins like typhoid fever - with fever, chills, weakness, and severe loss of strength. The patient's consciousness is impaired, shortness of breath appears, and symptoms are dominated by intoxication, vomiting and lack of appetite. Tuberculosis rashes spread throughout all organs.
Acute miliary sepsis
Acute miliary sepsis is the most severe. This form of tuberculosis is classified as a separate group due to its immediate development and very high risk of death for the patient - mortality reaches 83%. The patient develops anemia within several hours, and the level of granulocytes and leukocytes drops sharply (below 1.5x109/l). Today this form of the disease is very rare.
In children, the abdominal and pulmonary types of miliary tuberculosis are most often diagnosed. The disease is acute and primarily affects the lungs, kidneys, liver and spleen.
Caseous pneumonia
Clinically, it resembles severe pneumonia with severe intoxication, pain in one of the halves of the chest, aggravated by breathing and coughing, an unproductive or dry cough, severe shortness of breath, indicating respiratory failure. This type of disease is the result of the spread of bacilli in the blood from the primary focus (caseous pneumonia is secondary). They may be complicated by a disseminated, infiltrative or fibrous-cavernous variant. Pneumonia is often complicated by bleeding from the lungs or pneumothorax.
Diagnostics
Primary diagnosis of the miliary form of tuberculosis is difficult and is usually based on the exclusion of other ailments or the doctor’s experience. The problems are caused by the absence of mycobacteria in the patient’s sputum and visible foci of dissemination in the lungs in the first two weeks.
To confirm the disease, many studies must be carried out. X-ray plays a leading role in miliary pulmonary tuberculosis. Starting from the third week, dissemination in the image shows multiple darkening with a clear outline.
Photo from the site gtrk-vyatka.ru
Other types of diagnostics:
- biochemistry and general blood test;
- general urine analysis;
- culture of sputum and other biological material;
- CT scan of the chest and abdomen, in complex cases multislice tomography;
- X-ray of other organs;
- bronchoscopy;
- Ultrasound examination.
In the meningeal form of miliary tuberculosis, studying the cerebrospinal fluid helps confirm the presence of the pathogen. If a large number of lymphocytes and protein markers are detected in the cerebrospinal fluid, the diagnosis can be considered established. Sometimes it is possible to isolate M. tuberculosis directly.
Damage options
As you know, the disease mainly affects people who are forced to live in crowded conditions and do not observe hygiene standards, first of all, who are deprived of the opportunity to breathe clean air. It is therefore not surprising that the most common forms of tuberculosis are pulmonary lesions.
Typically, the development of TBC in the upper respiratory tract, which becomes the most common portal for infection (oro- and nasopharynx, larynx, bronchi, trachea.
Lung lesions:
- primary complex
- pleurisy
- focal form
- infiltrative form
- miliary form
- disseminated form
- caseous pneumonia
- cavernous form
- fibrous-cavernous form
- cirrhotic form
- tuberculoma.
The intrathoracic lymph nodes are also involved in inflammation.
The stages of tuberculosis suggest primary or secondary TBC. The secondary process is the result of internal re-infection, when bacteria are eliminated from the primary focus (through the blood, lymph or bronchi) and cause another form of the disease.
They also distinguish between a CD-positive process, when mycobacteria are released into the external environment, and a CD-negative process, when mycobacteria do not enter the outside of the body.
Often the pathology is combined with occupational dust diseases of the lung tissue (coniotuberculosis). This is typical for workers in the stone processing, weaving, and mining industries.
In addition to the respiratory system, TBC also damages other parts of the body:
- intestines
- mesenteric lymph nodes
- layers of peritoneum
- bone tissue
- spine and joints
- visual analyzer
- meninges
- CNS
- urinary organs (eg kidneys)
- reproductive system
- skin and subcutaneous tissue
- lymph nodes.
Although the possibility of independent extrapulmonary disease is not denied, it is usually assumed that the primary lesion is somehow located in the lung. When the focus is not exactly detected, they talk about the diagnosis of tuberculosis intoxication.
Treatment
The basis of treatment for miliary tuberculosis is chemotherapy. It is carried out in a tuberculosis clinic, prescribing the maximum dose of the substance recommended for a specific age.
Anti-tuberculosis drugs:
- Ethambutol.
- Pyrazinamide.
- Rifampicin (Rifabutin is used for HIV-infected people).
- Tubazid.
Among the reserve medications for disseminated tuberculosis, the following are used: Cycloserine, Para-Aminosalicylic acid, Prothionamide, Amikacin and its analogues.
Along with chemotherapy, patients with acute miliary tuberculosis are prescribed antioxidants, vitamins, corticosteroids, hepatoprotective agents, antihistamines, and probiotics. The list of necessary drugs can be expanded depending on the location of tuberculosis foci. HIV-infected patients are additionally recommended to take antiretroviral medications (Zidovudine, Phosphazide, Stavudine)
Complications
If treatment is delayed, the miliary form can cause many serious complications, the most common of which are:
- Tuberculous meningitis. Found in 30–50% of patients hospitalized with the miliary form.
- Inflammation of the serous membrane of the pleura and peritoneum.
- Damage to the cervical lymph nodes.
- Hypokalemia. It is more common in elderly and senile patients, usually women.
- Blood disorders.
The most terrible complication of the miliary form of tuberculosis can be the stress reaction of the body, in which the functionality of two or more systems affected by the bacterium is disrupted.
Prevention
Measures to prevent miliary tuberculosis are few in number, but they are quite effective if they are followed. So, what do experts advise:
- Don't refuse vaccination. Miliary tuberculosis is often diagnosed in children under three years of age, so vaccination of newborns should be the basis for prevention.
- Carry out preventive measures and educational work among the population.
- Treat pulmonary lesions.
To prevent the miliary form of tuberculosis in children, it is very important to prevent them from actively communicating with patients, and if contact occurs, try to show the child to a phthisiatrician and undergo a medical examination.
Modern methods of therapy make it possible to completely get rid of miliary tuberculosis. But another problem remains - reduced immunity. If you do not correct resistance and increase vitality, the disease may return.
Author: Elena Medvedeva, doctor, especially for lechim-gorlo.ru
Survey plan
- Three-time (with a two-day break) examination of sputum for CD using microscopy. If the result is positive, consultation with a phthisiatrician and hospitalization.
- If the result is negative, a molecular genetic study of sputum is performed.
- Survey radiography of the chest organs.
- Diagnostic test with recombinant tuberculosis allergen.
- If the diagnosis is not confirmed or rejected, a spiral computed tomography is performed.
Useful video about tuberculosis
List of sources:
- Diagnosis and differential diagnosis of miliary pulmonary tuberculosis / N. V. Musatova, N. V. Kuzmina // Surgut State University, Surgut, 2013.
- Federal clinical guidelines for the diagnosis and treatment of disseminated (miliary) pulmonary tuberculosis in children / V.A. Aksenova / Moscow, 2013.
- Tuberculosis. Features of the course, possibilities of pharmacotherapy. Textbook for doctors / A.K. Ivanov // St. Petersburg, 2009.
- Phthisiology. Textbook / Rakisheva A.S., G. Tsogt. // Almaty, 2014.
Forecast
The prognosis regarding the development of the disease is disappointing. This is due to the difficulty of diagnosis.
If the correct diagnosis is established and timely treatment is carried out, the patient has a high chance of recovery. For this purpose, you should follow the recommendations and instructions of your doctor, as well as lead a healthy lifestyle.
In the absence of drug treatment, cavities can form, causing the collapse of the lungs, and caseous pneumonia can develop.
