23.5 : 使用免疫调节剂治疗炎症性肠病（IBD) 中的克罗恩病

Crohn's disease is an inflammatory bowel disorder characterized by discontinuous chronic inflammation of the GI tract.

Treatment strategies encompass immunomodulatory agents, glucocorticoids, and biologics or anti-TNF therapy.

Based on the extent and severity of the inflammation, immunomodulators, such as azathioprine, 6-mercaptopurine, and methotrexate can be administered with glucocorticoids or anti-TNF agents.

Azathioprine is metabolized into 6-mercaptopurine that subsequently forms active 6-thioguanine nucleotides, which inhibits purine synthesis and cell proliferation.

These drugs help maintain remission, prevent post-surgery recurrence, and treat fistulas in Crohn's disease.

Their adverse effects include nausea, vomiting, pancreatitis, fever, rash, and decreased blood cell counts via bone marrow suppression.

Methotrexate inhibits dihydrofolate reductase, suppressing immune cell proliferation and inducing cell death. It also inhibits purine metabolism, T-cell activation, and cytokine production, providing anti-inflammatory effects.

Side effects may include headache, vomiting, abdominal discomfort, rash, and RBC enlargement or macrocytosis.