未分化结缔组织病：患者指南

Overview

Crohn's disease is a type of inflammatory bowel disease (IBD). It causes chronic inflammation that can involve any part of the gastrointestinal tract from the mouth to the anus, most often the end of the small intestine (ileum) and the beginning of the large intestine (colon). Unlike ulcerative colitis, which mainly affects the colon lining, Crohn's can involve deeper layers of the bowel wall and may create skip areas of healthy tissue between inflamed sections.

It is a lifelong condition with periods of active symptoms (flares) and quieter times (remission). There is no cure yet, but modern treatments help most people control inflammation, heal the bowel, and maintain a good quality of life. Early diagnosis and consistent management reduce the risk of complications such as strictures (narrowing), fistulas (abnormal connections), abscesses, or the need for surgery.

Signs & Symptoms

Symptoms vary widely depending on which part of the gut is affected and how active the inflammation is. They often develop gradually and can come and go.

• Persistent diarrhea (sometimes with blood or mucus)
• Abdominal pain and cramping, often in the lower right side
• Urgent need to have a bowel movement
• Unintended weight loss and reduced appetite
• Fatigue and low energy
• Fever during flares
• Mouth sores, joint pain, skin rashes, or eye inflammation (extra-intestinal symptoms)
• In children: delayed growth or puberty

Causes & Risk Factors

The exact cause is not fully known. Crohn's disease involves an abnormal immune response in which the immune system attacks the digestive tract, leading to ongoing inflammation. Genetics, the gut microbiome, environmental triggers, and immune system dysregulation all play roles.

• Family history of IBD increases risk
• Smoking is a major modifiable risk factor that worsens disease course and reduces treatment response
• Age: most often diagnosed between 15 and 35 years, though it can occur at any age
• Certain medications (such as NSAIDs) or infections may trigger flares in susceptible people
• Diet and stress do not cause Crohn's but can influence symptoms

Diagnosis

Diagnosis usually involves a combination of medical history, physical exam, laboratory tests, imaging, and endoscopy with biopsies. No single test confirms Crohn's disease; doctors look at the overall pattern.

• Blood tests for anemia, inflammation markers (CRP, ESR), and nutritional deficiencies
• Stool tests to rule out infection and check for calprotectin (a marker of intestinal inflammation)
• Colonoscopy or upper endoscopy with tissue biopsies
• Imaging such as CT or MR enterography to view the small bowel
• Capsule endoscopy in selected cases

Treatment & Management

Treatment aims to induce and maintain remission, heal the intestinal lining (mucosal healing), prevent complications, and support nutrition and quality of life. Care is personalized and often involves a gastroenterologist, dietitian, and sometimes a colorectal surgeon. Therapy is stepped according to disease location, severity, and response.

• Medications: aminosalicylates (limited role), corticosteroids for short-term flares, immunomodulators (azathioprine, methotrexate), biologics (anti-TNF agents, anti-integrins, anti-IL-12/23), and small-molecule drugs such as JAK inhibitors
• Nutritional therapy: exclusive enteral nutrition can induce remission especially in children; ongoing dietitian support for deficiencies and symptom management
• Surgery: reserved for complications (strictures, fistulas, abscesses, or failure of medical therapy); bowel-preserving approaches are preferred
• Supportive care: iron, vitamin B12, vitamin D, and other supplements as needed; pain management that avoids NSAIDs when possible
• Regular monitoring: bloodwork, stool markers, and endoscopic or imaging assessment of healing

Living With It

Most people with Crohn's disease lead active, fulfilling lives with good disease control. Building a partnership with your care team, learning your personal triggers, and prioritizing self-care make a big difference. Smoking cessation is one of the most powerful steps you can take. Mental health support is important because living with a chronic condition can affect mood and stress levels, which in turn may influence symptoms.

Keep a symptom and food diary if helpful, stay up to date with recommended vaccinations (especially before starting certain immunosuppressants), and discuss family planning, work, travel, and exercise openly with your doctors. Many people find peer support through patient organizations valuable.