After being infected with HIV, most of them become asymptomatic HIV carriers or have no obvious symptoms, that is, they are called subclinical patients in medicine, and only some patients have clinical symptoms. The number of people infected with HIV is about 50 ~ 100 times that of AIDS cases. How many people are likely to get AIDS? According to the analysis of recent data, only 10% ~ 30% people develop AIDS within five years after being infected with HIV, and 25% ~ 30% people may develop AIDS-related syndrome. Most HIV-infected people develop AIDS within 10 years after infection, and some infected people may also develop HIV nervous system diseases. Aids is characterized by fatal opportunistic infections and malignant tumors, and the mortality rate is extremely high. The main complications were pneumocystis carinii pneumonia (60%) and Kaposi sarcoma (33%). Three to six weeks after being infected with HIV, symptoms such as general malaise, fever, chills, joint pain and diarrhea may appear, lasting for 7 to 14 days. After 2 ~ 3 months, the serum antibody may be positive, and then the infected person will turn to asymptomatic period (incubation period). The incubation period of AIDS (the period from HIV infection to onset is called incubation period) varies with the patient's age, route of infection, dosage and type of virus infection. According to recent reports, it is generally believed that the incubation period for adults is 8-9 years, and the average incubation period for children is 1.2 years. Some cases are persistent asymptomatic HIV carriers, even though they have been infected for many years. The dose of HIV infection through blood transfusion is large and the incubation period is relatively short. Children are 1.97 years old, adults are 8.23 years old and the elderly are 5.5 years old. The dose of sexual contact infection is small, and the incubation period is relatively long, generally 6-8 years, and the longest is 15 years. The incubation period of AIDS caused by HIV-II is as long as 16 ~ 19 years. Although patients have no clinical symptoms in the incubation period, HIV carriers are an important source of infection for spreading AIDS.
(1) Common symptoms and signs
1. Systemic symptoms
The most common clinical symptoms of AIDS patients are recurrent low fever (about 72%), accompanied by chills, emaciation, fatigue and weakness, weight loss (up to 5 ~ 22 kg), followed by extreme lethargy and weakness, which can not support normal physical activities. Chronic diarrhea is also a very obvious early clinical manifestation of some AIDS patients. And often can't find the cause of fever, diarrhea and weight loss. According to the analysis of the clinical manifestations of 38 cases of AIDS, the above symptoms and signs account for more than 80% of the total cases.
2. Lymph node enlargement
The incidence rate was 55% ~ 100%. When patients in high-risk groups have systemic lymphadenopathy that cannot be explained by other reasons, it is likely to be related to HIV infection. Although swollen lymph nodes are systemic, they are more common in cervical, submandibular or axillary lymph nodes. The swollen lymph nodes are not fused, hard, occasionally tender, and the surface skin has no change. The degree of lymphadenopathy is related to the titer of HIV antibody in serum. In addition, AIDS is accompanied by lymphoma, including Burkitts' lymphoma, immunoblastic lymphoma and Hodgkin's disease, and lymphadenopathy may also occur.
3. Skin damage
Skin mucosa is one of the main components of AIDS. Many AIDS patients take skin damage as the first symptom. Clinical manifestations are varied, such as rash, systemic itching, condyloma acuminatum, contact condyloma, urticaria and so on. However, the most characteristic skin damage is the skin change of Kaposi's sarcoma, and its damage performance will be introduced in the later chapters, so I won't repeat it here.
4. Central nervous system symptoms
Neurological disorders are considered to be the common causes of AIDS morbidity and mortality in children and adults. Clinically, 20% ~ 40% of AIDS patients have nervous system diseases. In autopsy, 7q% ~ 80% patients have central nervous system diseases, and the symptoms of central nervous system often coexist with symptoms caused by various opportunistic infections, with subacute encephalitis being the most common one. The etiology of the disease is unknown, there is no obvious inflammatory reaction, and there is nonspecific leukodystrophy, which is often the first symptom of AIDS. It often begins with fatigue and decreased libido, and later develops into severe dementia. According to the autopsy of 2 AIDS deaths in new york 102, 96 cases (94. 1%) had diffuse or localized brain damage. Among 65 patients with dementia before death, 45 (69.2%) had diffuse brain injury. In addition, it was reported that 235 AIDS patients were consulted for psychosis, and it was found that 12 1 case (accounting for 5 1.5%) had different degrees of dementia. In addition, encephalitis or encephalitis induced by conditional pathogenic bacteria is often seen in patients in the later stage.
(2) Clinical manifestations of opportunistic infections.
The so-called opportunistic infection, that is, conditional pathogenic factors, refers to some microorganisms with low invasiveness and weak pathogenicity, which cannot cause disease when the human immune function is normal, but when the human immune function is reduced, it creates infection conditions for such microorganisms to attack the human body and cause disease, so it is called opportunistic infection. Autopsy results show that 90% of AIDS patients died of opportunistic infections. There are dozens of pathogens that can cause opportunistic infection of AIDS, and many pathogens are often mixed. It mainly includes protozoa, viruses, fungi and bacterial infections.
1. Protozoa
(1) Pneumocystis carinii pneumonia: Pneumocystis carinii is a small protozoan, which specializes in making holes in human lungs. People can't see it with the naked eye, and they can't find it with ordinary biological culture methods. Pneumocystis carinii pneumonia is mainly transmitted through the respiratory tract through air and droplets. When healthy people are infected with HIV, their immune function is destroyed. At this time, Pneumocystis carinii will take advantage of the situation and multiply in patients, filling alveoli with exudate and various forms of Pneumocystis carinii, causing serious damage to the lungs. Pneumocystis carinii pneumonia was a rare infection before the AIDS epidemic. In the past, it was only found in infants during war and hunger, or in leukemia children receiving immunosuppressive treatment. Pneumocystis carinii pneumonia is a common cause of death among AIDS patients, which is the most serious opportunistic infection among more than 60% AIDS patients, and about 80% AIDS patients will have pneumocystis carinii pneumonia at least once. When AIDS patients are complicated with Pneumocystis carinii pneumonia, symptoms such as progressive malnutrition, fever, general malaise, weight loss and lymphadenopathy first appear. Cough, dyspnea, chest pain and other symptoms occurred later, and the course of disease was 4-6 weeks. Fever (89%) and shortness of breath (66%) are the most common symptoms of the lungs. Some people can still hear lung rales. Pneumocystis carinii pneumonia is a common cause of death in AIDS patients, which often occurs repeatedly and has a serious condition. Chest x-rays of pneumocystis carinii pneumonia show extensive infiltration of both lungs. However, a few patients (about 23%) can show normal or very few abnormalities on chest radiograph. According to the X-ray examination of 180 cases of pneumocystis carinii pneumonia, 77 cases showed bilateral interstitial pneumonia, 45 cases showed interstitial and alveolar inflammation, 26 cases showed interstitial inflammation around hilum, 24 cases showed unilateral alveolar and interstitial inflammation, and 8 cases were normal. Pulmonary function examination showed that the total lung volume and vital capacity decreased, and further aggravated with the progress of the disease. Pneumocystis carinii can be found in specimens taken by bronchoscopy or lung puncture, and sometimes other pathogens can be found. This is a mixed opportunistic infection. The course of disease is urgent; It can also be slow and eventually die of progressive dyspnea, hypoxia and respiratory failure, with a mortality rate of 90% ~ 100%.
(2) Toxoplasma gondii infection: Toxoplasma gondii infection in AIDS patients mainly causes toxoplasmosis in the nervous system, with an incidence rate of 26%. The clinical manifestations are hemiplegia, focal neurological abnormality, convulsion, disturbance of consciousness and fever. CT examination showed single or multiple lesions. Toxoplasma gondii can be seen according to histopathological section or cerebrospinal fluid examination. Very few toxoplasmosis involved the lungs (1%). The disease is an animal infectious disease caused by parasitic protozoa Toxoplasma gondii. The route of human infection, congenital infection is transmitted from mother to fetus through placenta. Acquired infection is caused by eating raw or undercooked meat containing cysticercosis.
(3) Cryptosporidiosis: Sarcocystis is a small protozoa parasitic on domestic animals and wild animals. People attach to the epithelium of small intestine and large intestine after infection, which mainly causes malabsorption diarrhea. The patient showed uncontrollable watery stool, losing 3- 10 liter of water every day, and the mortality rate could be as high as 50%. Diagnosis depends on colonoscopy biopsy or finding oocysts in feces.
2. Virus
(1) cytomegalovirus infection: According to serological investigation, cytomegalovirus is widespread, and most patients infected with cytomegalovirus are asymptomatic, but patients infected with cytomegalovirus can excrete virus in urine, saliva, feces, tears, milk and semen for a long time. It can be transmitted through blood transfusion, mother's placenta, organ transplantation, sexual intercourse and breastfeeding. When AIDS is accompanied by cytomegalovirus infection, it is often manifested as hepatitis, cytomegalovirus pneumonia, cytomegalovirus retinitis, thrombocytopenia, leukopenia and rash. In order to diagnose cytomegalovirus infection, inclusion bodies or isolated viruses must be found in biopsy or autopsy samples. According to Guarda's autopsy study on 13 AIDS patients, the most common diagnosis was cytomegalovirus infection (12 cases), followed by Kaposi's sarcoma (l0 cases). All 12 cases of cytomegalovirus infection are disseminated and often involve two or more organs.
(2) Herpes simplex virus infection: its transmission route is mainly direct contact and sexual contact, but also through droplets. Viruses can invade the human body from respiratory tract, mouth, eyes, genital mucosa or broken skin. Pregnant women may also pass it on to their babies during childbirth. Infection with the virus can cause skin and mucous membrane damage of AIDS patients, involving oral cavity, vulva, perianal region, back of hand or esophagus, bronchus and intestinal mucosa. Herpes simplex in the mouth and lips is the most common, and its damage is characterized by dense clusters of small blisters, which are slightly red at the base and can form ulcers after being scraped off. Ulcer is characterized by large, deep and painful, often accompanied by secondary infection, severe symptoms, long course of disease, and the damaged part can be cultured.
(3) Epstein-Barr virus: The infection rate of this virus in AIDS patients is very high. Epstein-Barr virus antibody can be detected in the serum of 96% AIDS patients. Epstein-Barr virus can cause primary mononucleosis, accompanied by hemolytic anemia, lymphadenopathy, systemic macula and T cell reduction.
3. Fungi
(1) Candida albicans infection: Candida albicans is a conditionally pathogenic fungus, which often exists in normal skin, mouth, upper respiratory tract, intestine and vaginal mucosa, and can be cultured from skin and mucosal secretions, urine and sputum. When the human body's resistance drops or the flora in the body is out of balance, Candida albicans can become a pathogenic bacteria, causing candida infection. It can be divided into cutaneous candidiasis and mucosal candidiasis. The latter is more common as thrush-the milky white film on the oral mucosa, glossopharyngeal mucosa, gums or lips, which is easy to peel off, revealing a fresh and moist ruddy base. More common in the late stage of serious diseases, or HIV-infected people. If homosexuals continue to have thrush without other explanations, it often indicates that patients have been infected with HIV or will develop into AIDS. Candidal esophagitis can cause dysphagia and pain or retrosternal pain. Esophagoscopy showed irregular ulcer and white false membrane in esophageal mucosa. Others include meningococcal keratitis, candidal vaginitis, candidal balanitis and visceral candidiasis. The diagnosis of candidiasis in skin and mucosa depends on clinical manifestations and fungal examination.
(2) Cryptococcosis is an acute or chronic deep fungal disease caused by Cryptococcus neoformans infection. When the human body's resistance is weakened, it is easy to invade through the respiratory tract and occasionally through the intestine or skin. Cryptococcal meningitis is a common complication of AIDS. The mortality rate is very high, which is characterized by fever, headache, insanity and meningeal irritation. Cryptococcus pulmonalis, subacute or chronic onset, accompanied by cough, excessive phlegm, low fever, chest pain, fatigue and nonspecific changes in X-ray examination. The diagnosis of cryptococcosis is mainly based on clinical manifestations and fungal examination.
4. Bacteria
(1) Mycobacterium tuberculosis: Mycobacterium tuberculosis often occurs in patients who have been infected with AIDS but have not yet been infected with AIDS. This may be because Mycobacterium tuberculosis is more virulent than other AIDS-related pathogens, such as Pneumocystis carinii, so tuberculosis is more likely to occur in the early stage of immunodeficiency. 74% ~ 100% of AIDS patients with pulmonary tuberculosis suffer from pulmonary tuberculosis, and its symptoms and signs are often difficult to distinguish from other AIDS-related pulmonary diseases. Aids patients often show diffuse infection. The most prominent clinical feature of AIDS patients complicated with tuberculosis is the high incidence of extrapulmonary tuberculosis. More than 70% of AIDS tuberculosis patients or patients diagnosed with tuberculosis have extrapulmonary tuberculosis. The most common forms of AIDS complicated with extrapulmonary tuberculosis are lymphadenitis and miliary lesions, which usually affect bone marrow, genitourinary tract and central nervous system.
(2) Atypical mycobacterial infection: It is one of the important complications of AIDS, often involving liver, lung, spleen, kidney, blood, bone marrow, gastrointestinal tract and lymph nodes. Its manifestations are fever, emaciation, malabsorption, lymphadenopathy and hepatosplenomegaly. Laboratory examination is nonspecific, and diagnosis depends on pathogen isolation, culture and biopsy.
(3) Other common pathogens: Pseudomonas aeruginosa, Escherichia coli, typhoid Bacillus and Neisseria gonorrhoeae. Can lead to opportunistic infections.
(3) Clinical manifestations of Kaposi's sarcoma
Kaposi's sarcoma was originally a rare malignant tumor in elderly men. In North America and Europe, about 30% of people diagnosed with AIDS are accompanied by this sarcoma. Kaposi's sarcoma complicated with AIDS accounts for 46% in the early stage of homosexuality, generally 27%, and 65,438+06% in the case of Pneumocystis carinii, while the incidence of Kaposi's sarcoma in heterosexual or intravenous drug users is only 3.8%. Kaposi's sarcoma mostly invades the skin, but when AIDS is combined with Kaposi's sarcoma, its lesions spread rapidly and can invade many organs of the whole body, especially the lungs, digestive tract and lymph nodes. Causes pleural effusion, hemoptysis and upper gastrointestinal bleeding. Kaposi's sarcoma of the lung rarely shows symptoms and often coexists with opportunistic infection of the lung. Hilar lymph node enlargement and nodular infiltration around it, accompanied by bilateral interstitial changes, pleural effusion is its typical X-ray manifestation. Comparing patients with Kaposi's sarcoma with patients without Kaposi's sarcoma, it was found that the incidence of lung and pleural lesions in patients with Kaposi's sarcoma increased significantly. The incidence of intrahepatic Kaposi's sarcoma is 14% ~ 18.6%. Most of it is caused by dissemination, but some of it originated in the liver. There is no clinical diagnosis method, and the liver is usually involved before death.
Clinical manifestations of AIDS in children
The clinical manifestations of AIDS in children are similar to those in adults, but there are no lymphadenopathy, Kaposi's sarcoma and opportunistic infection. Almost all children with AIDS have hepatosplenomegaly, interstitial pneumonia and dysplasia. The analysis of the data of AIDS survivors shows that the clinical manifestations and age of patients in AIDS diagnosis are related to the survival rate. 50% children survived 12 months after diagnosis, and the one-year survival rate of children with pneumocystis carinii pneumonia under 12 months was only 30%. Pneumocystis carinii pneumonia in elderly children was 48%; 72% older children with other diseases. These findings are essentially consistent with the research results of different clinical centers. Clinical manifestations appeared in the early stage of children, usually including pneumocystis carinii pneumonia, wasting syndrome and encephalopathy in children aged 4 ~ 8 months. Early and late manifestations of children can range from persistent otitis media to severe bacterial meningitis or pneumonia. In opportunistic infections, the difference between children with AIDS and adults is that bacterial infections are very common in children with AIDS, while Kaposi's sarcoma is not as common as adults. In laboratory examination, the absolute number of lymphocytes in most children with AIDS is normal, which is the only immunological index different from adult AIDS.
(5) AIDS-related syndrome
Aids-related syndrome refers to a group of AIDS symptoms or signs in high-risk groups susceptible to AIDS, such as gay men and intravenous drug users. It is developed from HIV carriers or acute infection, characterized by generalized lymphadenopathy, accompanied by irregular fever, fatigue, sweating at night, chronic diarrhea, anorexia, weight loss, hairy white spots on the tip of the tongue and various nervous system symptoms. Mild opportunistic infections can also occur, such as thrush, herpes simplex, herpes zoster and molluscum. Peripheral blood leukopenia and thrombocytopenia, anemia, T4 cell decrease, T4/T8 ratio decrease, and allergy disappears; Cellular immune index and immune function are low, serum globulin is high, and HIV antibody can be detected in serum.