2016年 · 第36卷第07期

IBD was once regarded as a "Western disease". In recent years, its incidence is on the rise in China and Asia, especially in recent 20 years, the number of IBD cases in China has increased rapidly^[1]。 The incidence of IBD in China has experienced an evolutionary process from rare to common diseases.

CD has become the hottest topic in the field of digestion in the past decade. Although the understanding of this disease is gradually deepening, the confusion is also increasing. On the one hand, tuberculosis, which has plagued human beings for hundreds of years, is still rampant in China. On the other hand, the number of CD patients is increasing in China at a rather alarming rate. The clinical manifestations of CD and intestinal tuberculosis are surprisingly similar, but some treatment measures are completely opposite. The key methods of treating CD, such as immunosuppressants and biological agents, can make tuberculosis rekindle and spread, and misdiagnosis and mistreatment will lead to very serious consequences. Therefore, it is of great significance to distinguish CD from intestinal tuberculosis.

Pathological diagnosis plays an important role in the diagnosis and treatment of IBD, and is an indispensable part. Compared with tumors, IBD has no distinct and specific morphological manifestations, and is easily confused with other diseases such as infection, so it is relatively difficult to diagnose. Some methods and indexes of pathological diagnosis of IBD are introduced, hoping to be helpful to clinical work.

IBD refers to a group of chronic inflammatory reactive diseases of the intestine of unknown etiology, including UC and CD. Chronic inflammatory reactions occur repeatedly in the intestine of IBD patients, which are prone to multiple complications. colitis-associated colorectal cancer (CAC) is the most serious complication in patients with long-term IBD. Effective surveillance and chemoprevention are important means to prevent and treat IBD carcinogenesis.

CD can affect the entire digestive tract. From the point of view of the involvement site, 30% ~40% of the patients involved the small intestine alone, 15% ~25% of the patients involved the colon alone, and 40% ~50% of the patients involved the small intestine and the colon at the same time^[1]。 It can be seen that the proportion of CD patients involving the small intestine is very high, and the incidence of CD is increasing year by year in recent years, so small intestine-related diagnostic techniques are particularly important. For a long time, the small intestine has been regarded as the "black box" of the digestive tract. In the early years, only traditional imaging examinations could indicate small intestinal lesions. With the emergence of computed tomography enterography (CTE) and magnetic resonance imaging enterography (MRE), as well as the development of capsule endoscopy and enteroscopy, people's understanding of small intestine diseases has become more and more deep. These small intestine diagnostic techniques are not only used to assist in the diagnosis of CD, but also to assess the scope of disease involvement. At present, they are gradually applied to the assessment and even treatment of disease conditions.

Since Truelove and Witts proposed the use of glucocorticoids (hereinafter referred to as hormones) in 1950s, hormones have been one of the important drugs for the treatment of severe ulcerative colitis (SUC), which greatly improved the prognosis of the disease and reduced the mortality rate from 75% reported in 1933 to 7% in 1955^[1]。 However, hormone therapy is ineffective in about 30% of patients with SUC^[2]The prognosis is serious and the treatment is still very difficult. Even due to recent advances in surgical treatment and the use of various new biological agents, there is still a mortality rate of about 1%. At present, we review the literature at home and abroad to elucidate the concept and standard of hormone resistant SUC, and discuss some progress in its treatment.

IBD, including UC and CD, is one of the common digestive tract diseases in western countries, and its incidence is increasing in China. IBD treatment includes a variety of drugs, nutritional support and surgery, among which glucocorticoids (hereinafter referred to as hormones) are widely used for induction remission therapy in IBD patients during the active phase, but some patients still develop hormone dependence. Immunosuppressants can help hormone-dependent IBD patients reduce hormone demand, help hormone withdrawal, and at the same time continue to maintain relief after hormone withdrawal. Therefore, in recent decades, the application of immunosuppressants at home and abroad has been on the rise. How to select immunosuppressants in hormone-dependent patients? How to apply? While referring to the experience of western countries, Chinese scholars have explored and accumulated some Chinese experience for the majority of clinicians to use as a reference when applying immunosuppressive drugs. However, there are also many controversial issues, which urgently need more domestic multi-center high-quality clinical research to solve.

In recent years, the incidence of CD in China has shown a rapid upward trend. CD mainly involves young adults, is incurable and disabling, and brings a heavy physiological, psychological and economic burden to patients, which has attracted great attention from the industry. The clinical manifestations of CD are complex and the course of disease is variable. The treatment of CD requires multi-disciplinary cooperation, and surgical treatment is an important part of it. Although surgery cannot cure CD, when drug treatment is ineffective, surgery can not only control clinical symptoms and induce disease remission, but also improve the quality of life of patients and even save their lives. Therefore, viewing CD surgical treatment objectively and rationally and standardizing CD surgical clinical practice are beneficial to the long-term and healthy development of CD surgical treatment in China. Based on the recent research achievements at home and abroad and the diagnosis and treatment experience of the author's team for nearly 10 years, this paper briefly expounds the progress of CD surgical treatment standards and understanding based on evidence-based medicine.

UC is a chronic non-specific inflammatory disease of the colorectum with unclear etiology. It is a common disease in North America and Europe. The incidence of UC in China has also been gradually increasing in recent ten years. Although most patients with UC are effective with medical treatment, about 20% to 30% still require surgical treatment.

CD is a chronic recurrent inflammatory reactive disease involving the entire digestive tract and is currently believed to be the result of the interaction of host, immune system, and environmental factors^[1]。 In recent years, although the use of biologics such as inflixi monoclonal antibodies has significantly reduced the risk of surgical treatment in CD patients, 70% of patients still need at least one surgical treatment in their lifetime^[2]。 However, intestinal resection is not a radical treatment for CD, and there is an urgent need for effective measures to prevent postoperative recurrence of CD. Therefore, this study retrospectively analyzed the medical records of 59 patients who underwent surgical treatment for CD, with the intention of analyzing the effect of azathioprine on postoperative recurrence.

IBD includes UC and CD. The incidence of IBD in China is increasing year by year, and UC is more common^[1]。 However, the exact pathogenesis of IBD is still unclear, and there is a certain risk of malignant transformation.

A 62-year-old male was admitted to the hospital on July 4, 2014 due to diarrhea, mucus, pus and blood for 2 weeks. Two weeks before admission, the patient will have diarrhea after exertion and eating spicy food, 4 to 6 times/d, yellow-green thin paste stool with a small amount of blood, lower abdominal cramps before defecation, which will be relieved after defecation. He underwent hemorrhoid surgery in an external hospital, and his condition worsened after the operation. He defecated mucus, pus and blood more than 20 times a day. He had obvious lower abdominal pain, tenesmus, fever and chills, and his body temperature was as high as 39.5℃. The intravenous drip treatment of levofloxacin in the external hospital was ineffective, so he was admitted to the ward of International Medical Department of Peking Union Medical College Hospital. The patient was previously in good health, smoked 40 cigarettes/d, and occasionally consumed alcohol. Physical examination: temperature 38.5 ℃, pulse 97 beats/min, respiratory rate 16 beats/min, blood pressure 125/75 mmHg (1 mmHg =0.133 kPa), BMI 24.8 kg/m²。 The superficial lymph nodes were not enlarged. Heart and lungs are not special. Soft abdomen, deep tenderness in the lower abdomen, no muscle tension, rebound pain, not reaching the liver and spleen under the costs. Intestinal sounds were active, 7-8 times/min. There was no edema in both lower limbs. Anal diagnosis showed rectal tenderness and finger cuffs withdrew from blood staining.

IBD, which mainly includes UC and CD, is one of the common digestive system diseases in China. Its etiology is still unclear, and its diagnosis and treatment are difficult^[1]。 On the basis of extensive research, some scholars have put forward the concept of continuum, which believes that IBD is caused by complex and interactive continuum lesions^[2]。 The continuum of complex interactions refers to the human intestine where host sources interact with foreign components, namely intestinal microorganisms, immune cells surrounding the intestinal epithelial cell barrier, genetic structures and environmental factors. Recent studies of the complexity of this microbial-immune-genetic axis have highlighted the characteristics of IBD as a clinical syndrome. The study generally revealed that IBD is a consequence of barrier dysfunction and accumulation of associated phenotypes. Thus, a wide range of interacting biological pathways are involved, including innate immunity, adaptive immunity, endoplasmic reticulum stress and autophagosomes, and metabolic pathways associated with cellular self-stabilization. In addition, the influence of the above-mentioned host factors (including microorganisms and other self-factors) and environmental factors before or after the occurrence of IBD is under further research and exploration.

Under the action of specific antigens, specific cytokines, and antigen-presenting cells, naive T cells can differentiate into Th1, Th2, Th17, and regulatory T cells (Treg), which are related to CD. Th1 cells are regulated by IL-12, express transcription factor T-bet, and secrete cytokines such as IFN γ, TNF α and IL-2. Th1 type immune response is related to inflammatory response and tissue damage. The recognition of Th2 depends on the transcription factor GATA3, which regulates the secretion of IL-4, IL-5 and IL-13, causing Th2-type immune response, and can suppress the tissue damage mediated by Th1-type response. The recognition marker of Th17 is retinoid-related orphan nuclear receptor γ T (ROR γ T), which secretes IL-17, IL-21, IL-22, IL-26, granulocyte macrophage-colony stimulating factor (GM-CSF), TNF α, IFN γ, IL-8, IL-10 The CXC chemokine CCL20 (whose ligand is CCR6) can induce and amplify the inflammatory response and participate in the occurrence and development of autoimmunity. Treg cells have immune regulatory function, can secrete TGF β and IL-10, inhibit T cell differentiation, activation, proliferation and cytokines, and the transcription factor is forkhead transcription factor P3 (FoxP3), which can maintain its function and inhibit the immune response of Th1, Th2 and Th17 cells. Th cell-associated transcription factors and cytokines are presented inTable 1。

IBD is a chronic non-specific inflammatory reactive disease of the intestine, mainly including UC and CD. With the improvement of people's living standards and sanitary conditions, the incidence and prevalence of IBD are increasing year by year in both developing and developed countries, which has become a health problem of global concern. IBD is an immune abnormal disease caused by genetic, environmental, immune and other factors, but its specific pathogenesis and etiology are still inconclusive. Studies have shown that the reduction of intestinal microbial polymorphism and the alteration of microbial stimulation lead to the impairment of the body's immunity and the disorder of intestinal immune regulation. The hygiene environment in early childhood has an important influence on the immune system of the body, and the hygiene hypothesis focuses on the influence of hygiene environment factors in early childhood on the occurrence of IBD in the future, which provides a good explanation for the high incidence of IBD. The relationship between hygiene hypothesis and IBD and its possible mechanisms are reviewed from the aspects of parasite and microbial infection, family size, living environment and family hygiene.