Digestive damage in acquired immunodeficiency syndrome

Introduction to digestive system damage in acquired immunodeficiency syndrome AIDS, acquired immunodeficiency syndrome (AIDS), is a fatal disease caused by human immunodeficiency virus (HIV) through sexual contact or blood, blood products and mother-to-child transmission. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific population Mode of transmission: sexual contact, spread of blood, mother-to-child transmission Complications: pneumonia candidiasis toxoplasmosis Hodgkin's lymphoma diarrhea

Causes of digestive system damage in acquired immunodeficiency syndrome

HIV infection (30%):

HIV is a cytocidal virus, belonging to the family of retroviruses, lentiviruses, and primate immunodeficiencies. The nucleic acid of HIV can integrate with the DNA of the host infected cells, making it difficult for HIV to be eliminated from the body. HIV can interact with cells. The surface of the CD4 molecule binds, and under the action of a synergistic receptor such as CCR5 and CXCR4, it adheres to the host cell, fuses, and penetrates into the host cell membrane.

Pathology (30%):

The susceptible cells of the virus include T helper cells, monocytes, macrophages, glial cells, etc. After HIV invades the helper T lymphocytes, reverse transcription is performed to integrate the viral genes into the host cell chromosomes, and transcription is performed. , translation, replication of a large number of viruses, cell destruction, helper T lymphocytes are important immune cells in the human body, the destruction of HIV-assisted T cells and other immune cells, can seriously weaken the body's immune response to foreign antigens, destroy the virus The protective effect of mycobacteria, fungal infection and immune surveillance on tumor antigens leads to the gradual decline of immune function, so AIDS patients are prone to refractory opportunistic infections and tumors, AIDS digestive tract damage.

Immune function defects (30%):

Mainly related to gastrointestinal immune function defects, clinical manifestations of various pathogen infections, such as protozoa, viruses, bacteria, fungi and atypical tubercle bacilli infection, can also occur in a variety of tumors, such as Kaposi sarcoma (Kaposi Sarcoma, KS), lymphoma, etc.

Prevention of digestive system damage in acquired immunodeficiency syndrome

Preventing the occurrence of AIDS is particularly important. Prevention, treatment and care are the three magic weapons against AIDS, strictly control the spread of blood channels, formulate blood donation regulations, promote the use of condoms, strengthen sexual safety education, and reduce the harm of intravenous drug addicts. The use of effective AIDS vaccines and the like is an effective method for controlling and preventing the spread of AIDS.

Complications of digestive system damage in acquired immunodeficiency syndrome Complications pneumonia candidiasis toxoplasmosis Hodgkin's lymphoma diarrhea

1. Various opportunistic infections and tumorigenesis

Such as Pneumocystis carinii pneumonia, the incidence rate of 50% to 60%, manifested as cough, cough, shortness of breath, lung signs are not many, chest X-ray examination mostly bilateral interstitial inflammation or perihepatitis; It is an important cause of death in AIDS patients. Candidiasis is caused by Candida albicans, often manifested as oropharyngeal inflammation, esophagitis and gastroenteritis, and can also occur in human herpesvirus infection, brain toxoplasmosis, etc. Kaposi sarcoma or non-Hodgkin's lymphoma is most common.

2. Gastrointestinal infection

Such as esophagitis or esophageal ulcer can cause swallowing pain and post-sternal discomfort, esophageal ulcer can also produce blood at the same time, colonitis can cause watery diarrhea, if the ulcer is combined, there is a risk of intestinal perforation.

Symptoms of Digestive System Damage in Acquired Immunodeficiency Syndrome Common Symptoms HIV Infection Immune Deficiency Lean Fatigue Immune Damage Abdominal Pain Bacterial Infection Dysphagia Tobac

When HIV enters the human body, it can cause primary and secondary damage to the digestive system, as shown below.

Oral cavity

AIDS patients may be associated with various infections of the mouth, herpes simplex virus (HSV) infections of the lips and oral Candida albicans infections are most common. The former manifests as: high density around the lips and mouth, small groups of blisters, bases Slightly red, the blisters can form ulcers after being rubbed, which is characterized by large and deep lesions, pain, often accompanied by secondary infections, more serious symptoms, long duration of disease, cultured HSV in the affected area, biopsy Typical inclusion bodies can be found. Candida albicans stomatitis can be as high as 43% in children with AIDS. The clinical manifestations are oral mucosa, milky white patches on the tongue and throat, gums or lip mucosa, easy to peel off, revealing fresh Wet rosy base, the patient feels obvious pharyngeal discomfort, sore throat, difficulty swallowing, swallowing pain, fear of eating due to pain, etc., can be found in the secretion smear Candida.

2. Esophagus

The main manifestations of AIDS complicated with esophageal lesions are: esophagitis, esophageal Kaposi's sarcoma, abnormal esophageal motility, etc. Among them, opportunistic infections are the most common of candidal esophagitis, many AIDS patients, often with esophageal opportunistic infections as the first Symptoms, it is one of the manifestations of poor long-term prognosis of AIDS, often occurs in CD4+ cells <100 / l, esophagitis can exist alone or with stomatitis, fungi (Candida albicans), virus (herpes simplex virus HSV, Cytomegalovirus (CMV) and other pathogens are common causes. The clinical manifestations are post-sternal discomfort, increased post-sternal pain during swallowing, difficulty in swallowing, etc. Endoscopically, some or all of the esophagus may be affected, which is characterized by diffuse hyperemia of the esophageal mucosa and becoming brittle. , erosive, ulcer, mucous membrane surface covered with white pseudomembrane, endoscopic cell brush can find Candida.

Candida esophagitis is often satisfactory after antifungal treatment, which can significantly improve the quality of life of patients, but it is easy to relapse. In recent years, with the clinical application of highly active antiretroviral therapy (HAART), candida The incidence of esophagitis is significantly reduced.

Zalar's study showed that in patients with AIDS, with or without esophageal damage, with or without endoscopic esophagitis, 88.8% of patients may have abnormal esophageal manometry, manifested as non-specific esophageal dysfunction, nutcracker Esophageal esophagus, elevated esophageal sphincter (LES) pressure with relaxation disorder.

3. Gastroduodenal lesions of stomach and duodenal AIDS are: gastrointestinal infections and tumors, tumors of the stomach and duodenum, such as Kaposi's sarcoma (KS), non-Hodgkin's lymphoma (NHL) It is not uncommon. Kaposi's sarcoma of the stomach and duodenum is combined with KS of the skin or lymph nodes, but it can also exist alone. 38% of KS in AIDS can invade the stomach, and KS can be more in the gastrointestinal tract. However, the tumor volume is generally small, and lymphosarcoma is often one to several large tumors. Clinically, upper gastrointestinal bleeding, obstruction, anemia, etc., stomach and duodenitis appear as stomach and duodenum. Various opportunistic infections, such as cytomegalovirus infection, Cryptosporidium infection, Toxoplasma infection, etc., CMV gastritis can cause severe inflammation, ulceration, mucosal folds, edema, X-ray can be expressed as large gastric mucosa Area damage, Candida albicans can cause cellulitis inflammatory gastritis, AIDS patients can have reduced gastric acid, making bacteria easy to breed, endoscopic, KS and NHL and other tumors are not easy to identify, no specificity, and pathogens can be hidden in AIDS Normal gastrointestinal adhesion of the patient Inside, therefore, be a conventional pathology biopsy and culture.

The effect of gastrointestinal KS on chemotherapy is similar to that of skin KS. The KS of the duodenum and the limited KS of the lesion have the best effect on chemotherapy. Even if the lesion of KS is not finally solved, the gastrointestinal tract of the patient after chemotherapy. Symptoms can be improved, therefore, while using HAART, chemotherapy should be added to gastrointestinal KS.

4. Jejunum and ileum

In patients with AIDS, jejunum and ileum are involved. Common manifestations are Kaposi's sarcoma and infection in the small intestine. Pathogens are mostly pathogenic organisms, Cryptosporidium infected by protozoa, Mycobacterium avium in bacterial infection, Salmonella, curved. The genus is more common. The pathological changes of bacterial infection are similar to those of other organs, but the inflammatory response is generally mild. Most patients have no obvious clinical symptoms. Cryptosporidium infection is the most common cause of AIDS diarrhea, mainly manifested as malabsorption. Sexual diarrhea; can cause severe, watery, cholera-like diarrhea; watery stool is large, and difficult to control; may be associated with painful intestinal fistula, sometimes with nausea, vomiting, etc., in patients with CD4+ cells >200/l, this species Diarrhea is often self-limiting, and CD4+ cells <200/l infected, diarrhea is difficult to relieve, the patient's weight is significantly reduced, diarrhea-consumption syndrome, the mortality rate can be as high as 50% or more, the intestinal infection of Cryptosporidium It mainly relies on intestinal mucosal biopsy or the detection of protozoan oocysts in the feces. Only after repeated iterations of the feces and eggs are negative, can the infection be ruled out.

Chronic diarrhea is one of the most common and prominent manifestations of digestive tract in AIDS patients. The cause of AIDS diarrhea can be the effect of HIV itself on the intestinal mucosa, but it is often combined with infection by other pathogens, Cryptosporidium infection, bacteria in the small intestine. Infection, accompanied by pancreatitis, adenovirus colitis can cause severe digestive and dysfunction. About 50% of AIDS patients may have steatorrhea caused by fat malabsorption.

5. Colon and rectum

Common manifestations of AIDS large intestine damage are cancer of the colon and rectum, sarcoma (KS) and opportunistic infection. In the past 10 years, with the gradual increase of AIDS levels, the survival time of AIDS patients has been prolonged, and colorectal tumors have been found in AIDS patients. The chance of infection increased compared with the previous one. Among the 12 HIV-positive patients with colorectal tumors counted by Yeguez, 6 were adenocarcinoma (5 cases had metastasis at the time of diagnosis), 5 were non-Hodgkin's lymphoma, and 1 was Small cell carcinoma, 7 patients in this group underwent surgical treatment, but the prognosis was poor, and complications were prone to postoperative complications, such as infection of the incision. The pathogen causing colon and rectal infection was the amoeba, the blue Diptera and CMV, HSV is more, clinical manifestations of local redness, erosion ulcers, systemic fever and perianal pain and other inflammatory symptoms, endoscopic mucosal ulcer formation, CMV and HSV cause colon infection, severe ulceration and Perforation, colitis caused by Clostridium difficile is more common in AIDS patients, especially those who have been treated with antibiotics.

CMV infection was once the most common cause of opportunistic infections in the gastrointestinal tract, especially colonic infections. Colonoscopy showed that the lesions were mostly focal hyperemia or punctiform hemorrhage, occasionally small vesicles or erosions, and severe cases showed scattered distribution. In recent years, with the clinical application of highly effective combined antiviral therapy (HAART), CMV-induced intestinal infection has been significantly reduced, but other viruses such as astrovirus, rotavirus, adenovirus, etc., make AIDS patients Intestinal opportunistic viral infections become more complex, and adenovirus colitis is one of the causes of long-term diarrhea.

6. Anus

Anal and surrounding ulcers and tumors are common manifestations of AIDS. In advanced AIDS patients, perianal ulcers account for about 9.2%. Anal ulcers caused by HSV infection are chronic, often accompanied by mucopurulent discharge. It is generally believed that anal cancer is a sexually transmitted disease, squamous cell carcinoma is the main type, AIDS perianal human papilloma virus (HPV) infection, is an anal intraepithelial neoplasia, (anal intraepithelial neoplasia, AIN), a risk factor for anal cancer, anal cancer is characterized by local bleeding, pain, lumps, sometimes with itching, and the diagnosis depends on tissue biopsy.

Hepatobiliary

In the course of AIDS patients, liver and bile duct infections are common. Various viruses, bacteria, fungi and other opportunistic bacteria can invade the liver and bile duct, causing primary or secondary infection of liver and gallbladder. Histology can be granulomatous hepatitis. Pathological manifestations such as fatty liver, acute, chronic hepatitis and cirrhosis, bile ducts may have similar changes in sclerosing cholangitis.

The specific causes of liver parenchymal diseases, from high to low are Mycobacterium avium infection, cryptococcal infection, Kaposi's sarcoma, CMV virus infection, histoplasmosis, lymphoma, drug-induced hepatitis, small Bacillus, etc., the infection rate of Kaposi's sarcoma in the liver is 14% to 18.6%, mostly caused by systemic dissemination. The main manifestations of hepatitis in AIDS patients are: fever, abdominal pain, liver enlargement, abnormal liver function, Those who receive antiretroviral therapy can also be caused by the toxic effects of drugs on the liver. People with homosexuality, bisexual or intravenous drug use often combine with hepatitis B and C.

Common causes of biliary tract disease are cytomegalovirus infectious cholangitis, cryptosporidis infectious cholangitis, lymphoma, Kaposi sarcoma, etc. The main manifestations are long-term fever, right upper abdominal pain and liver function damage, etc. Contrast showed that the distal bile duct was narrow, the proximal end was dilated, the gallbladder wall was beaded, and the gallbladder removal and endoscopic nipple incision were effective in some patients.

8. Pancreas

In autopsy of AIDS patients, about 90% of patients have morphological changes of the pancreas, although most patients have no clinical symptoms, B-ultrasound has no gross morphological changes, no elevated blood glucose, etc., but histological changes such as acinar atrophy, enzyme Reduction of primary particles, nuclear degeneration and pancreatic fatty degeneration are found in most patients. Immunohistochemistry can show infections such as mycobacterial disease, toxoplasmosis, cytomegalovirus, Pneumocystis carinii, abdominal B-ultrasound, CT, tissue. An extraction or biopsy is helpful for diagnosis.

In short, the digestive system of AIDS patients has a variety of manifestations, different regions, different virus subtypes, different periods, performance has its own characteristics; but the gastrointestinal symptoms and AIDS cells have low immune function, easy to infect ordinary health people are not susceptible Infectious diseases are associated with tumors.

9. Clinical stage and classification of AIDS

(1) From HIV infection to onset, the typical clinical process can be divided into four phases:

1 acute infection period: more like flu-like symptoms.

2 incubation period: can last for months to years without symptoms.

3 Pre-AIDS: There are some non-specific symptoms (or symptoms), but it does not meet the diagnostic criteria for AIDS.

4 AIDS: HIV-positive people can be diagnosed with AIDS if they have one of the following conditions, such as bronchial, tracheal or pulmonary candidiasis, esophageal candidiasis, invasive cervical cancer, diffuse or extrapulmonary Sporozoosis, extrapulmonary cryptococcosis, chronic intestinal cryptosporidiosis (sickness > 1 month), cytomegalovirus infection other than liver, spleen, lymph nodes, leading to cytomegalovirus retinitis of blindness, HIV-related Encephalopathy, chronic ulcer caused by herpes simplex virus infection (sickness > 1 month) or bronchitis, pneumonia, esophagitis, diffuse or extrapulmonary histoplasmosis, chronic intestinal sporococcal disease (course > 1 month) ), Kaposi's sarcoma, Burkitt's lymphoma, immunoblastic lymphoma, primary brain lymphoma, diffuse or extrapulmonary mycobacterial disease, tuberculosis outside the lungs or extrapulmonary, diffuse or Other species outside the lung or mycobacterial infections that have not yet been identified, Pneumocystis carinii pneumonia, recurrent pneumonia, progressive multiple leukoencephalopathy, recurrent salmonella sepsis, cerebral toxoplasmosis, HIV wasting Syndrome, not every Infected patients will have complete stage 4 performance, but patients in each stage of the disease can be seen clinically. The different clinical manifestations of the four periods are a gradual and coherent progression of the disease.

(2) Typical AIDS has three basic characteristics:

1 severe cellular immunodeficiency, especially CD4 T lymphocyte defects.

2 Various fatal opportunistic infections occur, especially Pneumocystis Carini pneumonia (PCP).

3 a variety of malignant tumors, especially Kaposi's sarcoma (KS).

(3) According to the outstanding clinical manifestations of AIDS, AIDS can be divided into four types.

1 lung type: mainly due to difficulty in breathing, chest pain, chest X-ray film can present diffuse infiltration.

2 central nervous system type: the disease accounts for about 30% of AIDS, including the tissue amoeba caused by brain abscess, meningitis caused by Cryptococcus neoformans, progressive multiple leukoencephalopathy, subacute caused by cytomegalovirus Encephalitis, and mental retardation with unknown causes.

3 gastrointestinal type: with stubborn diarrhea and weight loss.

4 Unexplained causes of fever: general fatigue, weakness, weight loss, etc. are the main symptoms.

With the continuous improvement of HIV testing methods in recent years, the diagnosis of HIV infection is generally not difficult. The diagnosis of AIDS should be combined with medical history, physical examination and laboratory data.

Examination of digestive system damage in acquired immunodeficiency syndrome

Laboratory tests for AIDS patients include HIV pathogen testing, immunodeficiency testing, pathogenic diagnosis of opportunistic infections, and detection of tumor markers.

1. HIV pathogen detection virus isolation and culture, P24 antigen detection, PCR (polymerase chain reaction) detection of HIV RNA and HIV antibody detection, currently using enzyme-linked immunosorbent assay (ELISA) for HIV antibody screening test, as initially The screening test was positive, and the test was confirmed by Western blot or immunofluorescence (IF).

2. Laboratory examination of immunodeficiency examination of the total number of peripheral blood CD4 T lymphocytes, normal value > 1000 / l such as <200 / l, and anti-HIV antibody positive, can be diagnosed as AIDS can also detect CD4 / CD8 ratio, normal > 1 , AIDS patients <1.

3. Pathogenic diagnosis of opportunistic infections using serum immunological test methods to detect CMV, HSV, HBV, etc.

4. Digestion and absorption function check fat absorption test (Dung Sudan III staining, quantitative determination of fecal fat, 13C-triglyceride breath test), sugar absorption test (dextrose absorption test, hydrogen breath test, lactose Tolerance test), protein absorption test, etc. Small intestinal mucosal biopsy is helpful for clarifying the cause of malabsorption.

5. Endoscopy

Including gastroscopy, colonoscopy and biopsy histopathology, ERCP, anoscope and so on.

6.CT

The effect is the same as abdominal B-ultrasound, but the diagnosis of pancreatic lesions is more accurate, and CT-guided pancreatic puncture can still be performed, which is very helpful for opportunistic infection and tumor diagnosis of pancreas.

7. Gastric motility test

Esophageal manometry, gastric emptying test, anal pressure measurement can diagnose gastrointestinal dysfunction in AIDS patients.

Diagnosis and differentiation of digestive system damage in acquired immunodeficiency syndrome

diagnosis

According to the symptoms of digestive system symptoms and signs, the corresponding endoscopic examination, imaging examination, ultrasound examination and biopsy pathological examination and other experimental diagnostic techniques have practical significance for the diagnosis of the site or nature of the digestive system and the diagnosis of the tumor.

Differential diagnosis

Collagen colitis

The typical clinical manifestations are refractory, recurrent, chronic watery diarrhea, mostly at night, stools generally no pus, mucus or fat droplets, ranging from several times to dozens of times a day, diarrhea often lasts for months or even years Can also have abdominal pain, nausea, vomiting and other symptoms, severe diarrhea accompanied by dehydration, weight loss, generally no fever, rare due to severe dehydration, a small number of patients may appear chronic constipation, the disease often coexist with autoimmune Disease, up to 40% of patients have one or more autoimmune diseases, the most common being rheumatoid arthritis, thyroid disease and celiac disease.

2. Lymphocytic colitis

The course of the disease has been used for many years. Clinically, chronic watery diarrhea, abdominal pain and weight loss are the main manifestations. Some studies have shown that about 96% of patients have chronic diarrhea, and the amount of watery stool can be as high as 1500ml/d. Diarrhea, urgency or incontinence, 47% of patients with diffuse, intermittent mild abdominal cramps, 41% of patients with weight loss, in addition, water, electrolyte metabolism disorders, mild anemia can occur, There are also a small number of patients without diarrhea, this patient may be associated with thyroid disease, celiac disease, diabetes.

3. Radiation enteritis

Acute onset patients often have nausea, vomiting, diarrhea, loss of appetite, mucus and bloody stools after 1 to 2 weeks of radiotherapy, and there is a sense of urgency after the rectum is involved. In the late stage, there is chronic abdominal pain and it is more common in the lower abdomen of the umbilical cord. Intermittent, accompanied by fatigue and anemia, severe cases may occur intestinal obstruction, abdominal inflammation, abdominal abscess, intestinal fistula and other complications, and cancer may occur, once the radiation enteritis occurs, the process is likely to be uncontrollable, and may even lead to The patient died.

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