What is Primary HIV Infection?

Human immunodeficiency virus-infected AIDS (HIV / AIDS) patients have their immune function damaged due to the attack of HIV virus, and they often accompany multiple opportunistic infections. Among these opportunistic infections, tuberculosis is the most common opportunistic AIDS One of the infections, tuberculosis and AIDS is a concomitant disease that promotes the progression, deterioration and rapid death of patients. After HIV-positive patients are infected with tuberculosis, the incidence of tuberculosis is 30 times higher than that of HIV-negative patients. Existing research shows that the dual infection rate of human tuberculosis with tuberculosis within 9-12 years after human infection with HIV is close to 8%, and the mortality of patients with dual infection is as high as 1/3, which is much higher than the incidence of tuberculosis in the general population.

Basic Information

Multiple groups

Respiratory Medicine

Common locations

AIDS patient

Common causes

lung

Common symptoms

AIDS

Contagious

Cough, sputum, dyspnea and chest pain, etc.

way for spreading

Have

Causes of tuberculosis with AIDS

AIDS is the leading cause of TB.

Endogenous re-ignition

HIV infection can lead to potentially stable old tuberculosis lesions in the body, reactivation, and secondary tuberculosis.

2. Exogenous reinfection

Due to their low immunity, AIDS patients are prone to multidrug-resistant tuberculosis outbreaks and re-infection with tuberculosis bacteria, and they quickly become ill and worsen.

3. Primary infection

Most cases occur in countries and regions where the TB epidemic is very low, and people with HIV can develop primary TB.

The onset of AIDS is mainly caused by HIV infection. The HIV virus replicates in CD4 ⁺ cells in T lymphocytes, causing severe damage and destruction of cell functions, causing immune deficiency in infected organisms and even being caused by multiple organ failures. After the human body is infected with HIV, it is extremely difficult to remove the HIV in the body. After the HIV is continuously replicated, the human immune system is damaged, especially the absolute number of CD4 ⁺ cells is reduced, which increases the possibility of the human body being opportunistically infected. Studies have found that the infection rate of Mycobacterium tuberculosis (MTB) in HIV-infected people is as high as 58.8%. After HIV-positive patients are infected with MTB, MTB can easily multiply and spread in the patient's body so as to affect multiple organs of the infected person, and it is easy to cause recurrence of inactive tuberculosis lesions in the infected person. Studies show that both tuberculosis and HIV Infected patients account for more than 9% of HIV-positive patients. Mycobacterium tuberculosis infection can aggravate the course of HIV infection: Monocytes in patients with tuberculosis are more susceptible to HIV infection. After the body is infected with tuberculosis bacteria, it can induce the release of cytokines such as gamma interferon, interleukin-1 (IL-1), IL-2, and tumor necrosis factor, which can enhance HIV replication. Arabinose, the main component of the tuberculosis cell wall, is a potent inducer of HIV replication. Tuberculosis bacteria and pure protein derivatives can induce enhanced RNA expression of HIV in monocytes and increase P24 production.

HIV infection can affect the natural history of tuberculosis, as can tuberculosis. For example, CD4 lymphocytes in HIV-infected patients can promote HIV replication when activated by Mycobacterium tuberculosis. Clinically, the number of CD4 cells is directly related to the clinical manifestations of tuberculosis. CD4 cell counts are high in people who are not infected with HIV (> 300 × 10 ⁶ / L), and the lungs show typical tuberculosis lesions. Early lesions are mostly located in the upper lobe with or without cavities. After HIV combined with tuberculosis infection, the number of CD4 cells decreased, and the lesions were disseminated, spreading to both lungs or other organs throughout the body. The lungs can present with varying degrees of interstitial infiltration, some with progressive primary tuberculosis, hilar lymphadenopathy, and inferior lobe infiltration. When the patient's CD4 cell count is less than 200 × 10 ⁶ / L, some patients are prone to bacteremia. When the CD4 cell count is less than 100 × 10 ⁶ / L, the incidence of bacteremia is significantly increased.

Clinical manifestations of tuberculosis with AIDS

HIV-infected people, once in contact with bacillary tuberculosis patients, can easily become infected with tuberculosis, and rapidly deteriorate and spread. After becoming infected with HIV, TB patients become more pronounced and more rapid than those who are not infected with HIV.

Pulmonary tuberculosis can develop at any time during HIV / AIDS. Due to the patient's immunosuppressive ability, age, and other infections, the clinical manifestations are very different. The accompanying tuberculosis is most common in the lungs, except for cough, sputum, breathing In addition to common symptoms such as difficulties and chest pain, there are also symptoms of common tuberculosis, such as fever, night sweats, anorexia, and weight loss. In addition, a small number of patients will also have clinical symptoms such as high fever and respiratory distress. A summary of the current research results shows that the clinical characteristics of AIDS-associated tuberculosis are:

(1) The acute incidence is high, and the condition develops rapidly. Among them, acute cases are mainly miliary and exudative lesions. After infection with Mycobacterium tuberculosis in AIDS patients, Mycobacterium tuberculosis easily spreads rapidly in patients, and it is easy to activate inactive lesions in the body, which in turn can destroy pulmonary veins and lymph And spread throughout the body.

(2) Complications of opportunistic infections increase. Patients are prone to infectious diseases such as chronic infectious diarrhea, oral and esophageal fungal infections, lung infections, gastric bleeding, and anal genital warts.

(3) The positive rate of sputum culture is low, and the positive rate of tuberculin is low. In the early stages of tuberculosis infection, the positive rate of sputum antacid bacteria is high, and the positive rate of sputum smears is 31% to 89%; the number of CD4 ⁺ cells is> 200 cells / mm, and the PPD test is positive, and most patients have entered In the middle and late stages, most of the sputum smears were negative, the number of CD4 ⁺ cells decreased rapidly, and the results of PPD experiments were mostly negative.

(4) Long disease course, poor prognosis and high mortality rate. Compared with pure tuberculosis, the incidence of drug-resistant tuberculosis strains is extremely high in patients with AIDS-associated tuberculosis, and there will be certain restrictions between anti-TB treatment and anti-HIV treatment, which will affect the treatment effect, and even The two will also promote the rapid deterioration of the two diseases, so the disease duration is long, the prognosis is poor, and the mortality is high.

(5) There are many concomitant blood-borne diseases, including viral hepatitis such as hepatitis B and hepatitis C, and the incidence is highest among male drug users.

AIDS with tuberculosis test

HIV testing

There are currently more than 100 methods for detecting HIV, which can be divided into two categories: antibody detection and virus detection.

2. Chest imaging

The imaging manifestations of AIDS-associated tuberculosis are diversified. The imaging characteristics are as follows:

(1) The lesions are widely distributed. Simple tuberculosis occurs mostly in the posterior segment of the upper lobe or the lower segment of the lower lobe. The range of lesions is mostly limited to 1 or 2 lobe. The lesions associated with tuberculosis caused by AIDS can be anywhere in the patient's lungs. The characteristic of multiple distribution of the lung or both lungs is the involvement of multiple lobes and multiple lung segments. The cases of single lobe involvement are very rare. Among them, the diffuse distribution in the two lungs and the distribution of the upper and middle lungs are the most prominent. There is no significant difference in the distribution of.

(2) The lesions have various shapes. The morphology of AIDS-associated tuberculosis mainly includes patchy, flaky, large and small nodules, cords, pleural effusion, or miliary, hollow, calcified, and enlarged mediastinal lymph nodes. Each lesion can be isolated in a single case. Appears, and multiple lesions can appear together. In most patients' CT data, multiple lesions are often presented or there is more pleural effusion and pericardial effusion. In addition, a small number of patients have images such as cords, holes, or calcifications. The CT image showed clear lesions or plaques with sharp edges and intensified or even lesions.

(3) Hollowness increases as the condition worsens. In AIDS-associated patients with tuberculosis, small cavities are mostly located in the center of the nodule or parenchymal lesions. The inner wall is smooth, and it increases as the disease progresses. The incidence of cavitation in patients with tuberculosis at the late stage of the disease was significantly higher than that in early patients, and the cavities were more common in the upper and middle lung lobes, and even in the lower lung lobes, which were mostly wallless cavities and irregular inner walls.

(4) The incidence of hilar and mediastinal lymphadenopathy is extremely high. Enhanced CT scan showed irregular ring-shaped enhancement in most of the lesions and caseous necrosis in the center of the lesion, but there were not many typical tuberculosis lesions, and the proportion of mediastinal lymphadenopathy and pleural effusion was mostly. The pathological cause may be that the tuberculosis bacteria easily infect the mediastinal lymph nodes due to reduced cellular immune function, leading to enlarged lymph nodes. Compared with patients with simple tuberculosis, the incidence of hilar and mediastinal lymphadenopathy was significantly increased.

(5) Extrapulmonary tuberculosis occurs more frequently, mainly as superficial lymph nodes or para-mesenal and retroperitoneal lymphadenopathy, and a small number of patients develop spleen tuberculosis.

(6) More patients with pleural effusion. Mainly manifested as medium and below unilateral or bilateral effusion.

(7) Miliary lesions are more common. It may be caused by blood circulation caused by miliary tuberculosis or primary lesions in the lung.

(8) The density of lung parenchymal lesions is not large. CT of AIDS-associated tuberculosis often manifests as exudative lesions with a light patch density, less fibroproliferative lesions, calcifications, and cavity lesions, which are denser than simple tuberculosis lesions and have clearer patchy shadows. Calcified lesions and hollow lesions can to some extent indicate that there may be differences in immune status between the two.

3. Tuberculin test

The positive rate of tuberculin was high in HIV-infected patients with tuberculosis, and the tuberculin-positive rate was relatively low in AIDS patients with tuberculosis. The sputum-positive rate was also low.

Diagnosis of tuberculosis with AIDS

AIDS is diagnosed mainly by detecting pathogens. The detection rate of respiratory secretions smears is very low, and ultrasound can be used to conduct sputum guidance. The detection rate of pathogens precipitated by bronchial bronchial lavage fluid was 60% to 80%, and the positive rate of bronchoalveolar lavage fluid or transbronchial biopsy specimens could reach 90%. If necessary, percutaneous lung puncture or chest lung biopsy to confirm the diagnosis. Patients who have been diagnosed with HIV infection or AIDS with the aforementioned clinical, X-ray, and laboratory data can make a diagnosis.

Bacteriological examination. In 1989, the United States CDC recommended routine HIV screening for all TB patients. Traditional sputum bacteriological examination is still the most accurate method for diagnosing tuberculosis, but only open tuberculosis can be detected. It can not be detected when there are few bacteria. The sensitivity and specificity of detection are not high, so it is not recommended. In HIV infected people. In 2000, it was reported that the microscopic observation of the drug-sensitive method, that is, the cultivation of sputum tuberculosis bacteria in liquid medium, can detect characteristic cord-like factors in the early stages of MTB growth, and can detect multidrug-resistant tuberculosis bacteria.

AIDS-associated tuberculosis treatment

When developing treatment strategies for HIV / AIDS patients with mixed tuberculosis, effective treatment and control of tuberculosis remains central and priority because tuberculosis is an important cause of death among HIV-infected people. Due to the serious interaction between some antiretroviral drugs and anti-hormonal drugs, the toxicity of anti-hormonal drugs can be increased or the metabolic level of anti-retroviral drugs can be reduced, which complicates the treatment of mixed infections. In principle, once tuberculosis is diagnosed, anti- DOT therapy should be performed, and antiretroviral therapy should be postponed until the anti- treatment is completed.