Functional constipation（FC）refers to constipation that is not caused by organic diseases of the intestines or systemic conditions，nor by medication-related factors. It is typically characterized by a prolonged course and a tendency for symptoms to recur. When constipation symptoms persist despite standardized treatment and significantly impact daily life，it may be termed refractory FC. In recent years，some novel treatment approaches for refractory FC have begun to be applied in children. These include new medications such as prucalopride，lubiprostone，and linaclotide，as well as fecal microbiota transplantation（FMT），neuromodulation，biofeedback therapy，and antegrade continence enema（ACE）. This article reviews the current advances in the treatment of refractory FC in children，aiming to provide insights and directions for the application of new therapeutic methods in clinical practice in the future.

Crohn's disease（CD）is a chronic non-specific inflammatory bowel disease with unclear etiology and pathogenesis. Endoscopy combined with pathological examination remains the gold standard for diagnosing and monitoring CD activity. However，endoscopy is limited to the mucosal surface and intestinal lumen，making it difficult to assess the full thickness of the intestinal wall and extraintestinal conditions，and it cannot reach the proximal end of a narrowed intestinal segment. Additionally，endoscopic biopsy is invasive，requires thorough bowel preparation，and is poorly tolerated by infants and young children.This article reviews recent research advances in non-invasive examination methods for CD patients，including non-invasive biomarkers in blood and stool，as well as non-invasive imaging techniques，and their potential applications in the diagnosis and treatment of CD. By integrating these biomarkers with clinical parameters，it is possible to reduce reliance on invasive testing，optimize personalized treatment strategies，and enable early identification of disease activity and remission status. This comprehensive approach allows for more accurate assessment of disease progression，adjustment of treatment plans，and the delivery of more precise and individualized care for CD patients，ultimately improving their prognosis and quality of life.

Infliximab（IFX）is one of anti-tumor necrosis factor-α（anti-TNF-α）and is currently biological preparations with indications for the use of inflammatory bowel disease（IBD）of children in China.With the clinical application of IFX，the treatment goal of IBD has shifted from clinical remission to mucosal healing，thereby further improving the prognosis of the disease.However，in clinical work，it has been found that some children have primary or secondary unresponsiveness to IFX treatment，which is a major challenge during the IFX treatment process.Research has found that this phenomenon may be related to a decrease in blood drug concentration and the production of anti drug antibodies.Therefore，IFX therapeutic drug monitoring（TDM）is very important in the treatment of pediatric IBD.This article reviews the current application status of TDM in the treatment of IBD in children with IFX，and puts forward prospects for future research directions of TDM.

Biliary atresia（BA）is the most common cause of liver disease in children leading to liver transplantation.Kasai operation is the main treatment method.Earlier diagnosis and younger age of operation can greatly improve the prognosis.Although the diagnosis and treatment of BA have been gradually improved in recent years，some patients still need liver transplantation or even die due to cirrhosis.There is still a lack of non-invasive prognostic evaluation methods.This article reviews the value of serum matrix metalloproteinase-7（MMP-7）level in the early diagnosis of biliary atresia，and discusses the relationship between MMP-7 level and the prognosis of children with biliary atresia，and how MMP-7 participates in the mechanism of the occurrence and development of biliary atresia，so as to provide reference for clinical diagnosis and treatment.

Wilson disease（WD）is an inherited disorder caused by mutations in the ATP7B gene.It is characterized by pathological accumulation of copper in the organs throughout the body，especially the liver and brain. This article reviews the latest progress of existing and emerging therapies. At present，the most commonly used treatment methods are oral chelators of copper and zinc agents. Liver transplantation can be used as a treatment for end-stage patients. However，these treatment methods have some shortcomings：many side effects of drugs，poor treatment effect，lifelong treatment，poor patient compliance and so on. At present，the choice of drugs is still in the exploratory stage，and there are no guidelines to specify which patients should receive which treatment. In addition，there are many emerging therapies in different experimental stages，such as new chelators of copper，targeted molecular therapy，gene therapy and cell transplantation. The old methods have many disadvantages and lack large controlled clinical trials，and emerging research is still in its infancy，which are urgent questions.

Inflammatory bowel disease (IBD) is a type of recurrent chronic non-specific inflammatory disease of the intestinal tract with unclear etiology. The pathological features of IBD patients are the dysfunction of intestinal epithelial barrier and destruction of crypt. More and more evidences show the importance of epithelial barrier integrity in intestinal homeostasis. Barrier dysfunction in IBD patients occurs earlier than clinical symptoms, and accelerates the progression of the disease. This article mainly reviews the relationship between intestinal epithelial barrier and IBD from the composition and development of intestinal epithelium, and the progress of developmental signaling pathways in the pathogenesis of IBD, in order to provide the new ideas for the treatment of IBD.

Coagulopathy in patients with liver disease is considered to be a fragile "rebalancing" state.Conventional coagulation test commonly used in clinic can not reflect the whole process of coagulation, so its application is limited.In recent years, thromboelastography has developed rapidly as a rapid and real-time detection method to evaluate the coagulation status of whole blood, and has unique advantages in the application of liver disease.The article reviews the application in transfusion guidance of thromboelastography and its association with severity of liver disease, bleeding, thrombosis, mortality and conventional coagulation testing.Although thromboelastography has some shortcomings, it can better reflect the real coagulation state of patients with liver disease and help reduce the use of blood products.Pediatric data are scarce, but the use of thromboelastography alone or in combination with conventional coagulation test will have broad prospects.

Inflammatory bowel disease (IBD) is a type of recurrent chronic non-specific inflammatory disease of the intestinal tract with unclear etiology. The pathological features of IBD patients are the dysfunction of intestinal epithelial barrier and destruction of crypt. More and more evidences show the importance of epithelial barrier integrity in intestinal homeostasis. Barrier dysfunction in IBD patients occurs earlier than clinical symptoms, and accelerates the progression of the disease. This article mainly reviews the relationship between intestinal epithelial barrier and IBD from the composition and development of intestinal epithelium, and the progress of developmental signaling pathways in the pathogenesis of IBD, in order to provide the new ideas for the treatment of IBD.

Tumor-related diarrhea is a rare cause of chronic diarrhea in children, which is usually one of the clinical manifestations of specific functional syndrome of neuroendocrine neoplasms.Diarrhea may appear as the initial symptom or accompany symptom of disease progression, and it is generally relieved or cured after surgical resection.The present review mainly introduces several common neuroendocrine neoplasms which cause chronic diarrhea in children, and summarizes their different diarrhea features and mechanisms, as well as key points in diagnosis and treatment, in order to improve the rate of early diagnosis and prognosis of children.

Matrix metalloproteinases(MMPs)are a large family of zinc-dependent endopeptidases, which are mainly synthesized by connective tissues, it can degrade the extracellular matrix(ECM)and basement membrane, affect the regeneration and reconstruction of normal tissues, and participate in the pathological process of malignant tumors.Matrix metalloproteinase-7(MMP-7)is the smallest member of the metalloproteinase family.It is expressed in many tissues of the body, such as thyroid, breast, lung, digestive tract, reproductive system and hepatobiliary system.In recent years, the expression of MMP-7 in hepatobiliary diseases has attracted more and more attention.MMP-7 is not only involved in the growth, metastasis and invasion process of hepatobiliary malignant tumors, but also highly expressed in liver fibrosis, biliary atresia and other diseases.This paper reviews the expression of MMP-7 in the above diseases.