What Is Miliary Tuberculosis?

Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis. Mainly transmitted through the respiratory tract. It can occur in all organs of the body, but tuberculosis is most common. The disease is characterized by the formation of tuberculous nodules with varying degrees of caseous necrosis.

Acute miliary tuberculosis

Pulmonary miliary tuberculosis, also known as hematogenous disseminated tuberculosis. Acute miliary tuberculosis is often part of systemic miliary tuberculosis. Have low fever, fatigue, loss of appetite, cough, and a small amount of hemoptysis. However, most patients have mild lesions and often have no obvious symptoms. A few patients have a rapid onset of symptoms with highly toxic symptoms and obvious respiratory symptoms. Occasionally, the lesions can be limited to both lungs. This is because the bronchial hilarus or mediastinal lymph node caseous necrosis breaks into nearby veins (such as innominate veins, internal jugular veins, superior vena cava), and the liquefaction containing a large number of tuberculosis bacteria is spread to the lungs through the right heart and pulmonary artery. cause.

Overview of acute miliary tuberculosis

Macroscopically, the lungs were congested, weight increased, the cut surface was dark red, densely covered with gray-white or gray-yellow millet-sized nodules, slightly raised on the cut surface, and exposed on the surface of the lung membrane.

Signs and symptoms of acute miliary tuberculosis

Sudden onset of illness, infants often have sudden high fever (39-40 ° C), showing residual heat or relaxation fever, some cases may not be too high, showing regular or irregular fever, often lasting weeks or months, often accompanied by Shivering, night sweats, loss of appetite, cough, pale complexion, shortness of breath and cyanosis. Pulmonary rales can be heard in the lungs and have been misdiagnosed as pneumonia. About 50% of sick children show signs of meningitis at the time of onset. Some children are accompanied by hepatosplenomegaly and superficial lymph nodes, which may be clinically confused with typhoid fever and sepsis. A small number of infants and young children are mainly misdiagnosed as malnutrition due to general symptoms of poisoning such as fever, loss of appetite, weight loss and tiredness.

Milite tuberculosis of infants under 6 months is characterized by acute onset, severe and atypical symptoms, and many organs are involved, especially those with tuberculous meningitis. The disease progresses rapidly and the mortality rate is high.

Eye examination of patients with systemic miliary tuberculosis can reveal choroidal tuberculosis nodules, which are distributed around the central retinal artery branch.

Causes of acute miliary tuberculosis

Mycobacterium tuberculosis belongs to the genus Mycobacterium, according to acid resistance, aerobic bacteria, positive Gram stain, acid-resistant staining is red. Dividing propagation is slow, and it takes 4-6 weeks for colonies to appear on solid media. However, the isotope-labeled selective nutrient liquid medium (BACTEC) radiometric measurement system can be identified for 1-3 weeks of growth. Mycobacterium tuberculosis can be divided into 4 types: human type, bovine type, bird type, and mouse type. The human pathogens are mainly human type and bovine type, and human type is the main pathogen of deep human tuberculosis.

Pathophysiology of acute miliary tuberculosis

Most often occur within 3-6 months after the primary infection. Due to the low immune function of infants and young children, the body is in a highly sensitive state. After infection with tuberculosis, tuberculosis is easily formed. When the primary disease or lymphadenopathy occurs, a large number of bacteria invade the blood and cause acute systemic miliary tuberculosis. It can affect the lung, meninges, brain, liver, spleen, kidney, heart, adrenal glands, intestines, peritoneum, and mesenteric lymph nodes. The tuberculosis bacteria spread into the above organs form fine nodules in the interstitial tissue. Tuberculous nodules in the lungs are distributed in the upper and lower lungs, and are grayish-white translucent or light yellow opaque nodules, such as the tip of a needle or millet, about 1-2 mm in size. Microscopy revealed tuberculosis nodules consisting of epithelial-like cells, lymphocytes, and Langerhans cells plus central caseous necrotic lesions.

Diagnosis of acute miliary tuberculosis

The diagnosis is mainly based on the history of tuberculosis exposure, clinical manifestations, hepatosplenomegaly, and tuberculin test positive. Suspicious individuals should undergo bacteriological examination, serum anti-tuberculosis antibody detection and chest X-rays. The decisive effect is that early miliary shadows make up for both sides of the lung field. CT scans of the lungs show that the lung shadows show the size (1-3 mm), density (moderate), uniform (distribution of whole lung) shadows, and some lesions are fused.

Clinically, it should be distinguished from pneumonia, typhoid fever, sepsis, histiocytosis X, and hemosiderin in the lung.

The condition is more acute, but if early diagnosis and thorough treatment can still be cured, delay in diagnosis and treatment can lead to death.

Acute miliary tuberculosis treatment options

Early anti-TB treatment is important.

1.Anti-TB drugs

At present, the whole course of chemotherapy is divided into two stages. Namely intensive treatment phase and maintenance treatment phase. This program can improve the efficacy. The former starts with powerful quadruple bactericidal drugs such as INH, RFP, PZA and SM. Not only can it quickly kill tuberculosis bacteria in the growth and reproduction period, but RFP can also kill bacteria with low metabolism, and can prevent or reduce the generation of secondary resistant strains. SM can kill extra-cellular tuberculosis bacteria that grow, divide and reproduce actively in alkaline environment in China. PZA can kill intracellular binding bacteria and slow metabolizing tuberculosis bacteria in cheese lesions in acidic environment. The better the killing effect when starting treatment, the less chance of bacteria resistance in the future. This method is also effective for primary drug-resistant cases.

2.Glucocorticoids

Patients with severe poisoning symptoms and dyspnea can use prednisone 1-2 mg / (kg.d) for 1 to 2 months while applying the two anti-tuberculosis drugs.