We here describe a 50-year-old female patient with intestinal BD. The clinical characteristics and treatment measures of the patient are shown in  Table 1 . The patient has had recurrent oral and vulvar ulcers since 2003. In March 2004, she developed nocturnal hyperthermia and dark red bloody stools. Colonoscopy showed terminal ileum ulcers and proliferative lesions. Pathological biopsies reported acute and chronic inflammation of the superficial mucosa. Antinuclear antibody (ANA) and pathergy test results were positive, and the pure protein derivative (PPD) test was negative. Indexes such as infection, tumor, and autoantibody series were normal. According to the diagnostic criteria of the International Study Group for Behcet's Disease, and combined with clinical symptoms, laboratory tests, colonoscopy, and pathological findings, the patient was diagnosed with BD. Prednisone (40mg PO daily), cyclophosphamide (50mg PO daily), and mesalazine (4g PO daily) were administered to control symptoms. Prednisone and cyclophosphamide decreased gradually. In December 2005, cyclophosphamide was stopped, and 5mg of prednisone was taken orally daily to maintain symptoms. In August 2007, she developed multiple joint pains. There were no abnormalities in Anti-Streptolysin "O" (ASO), rheumatoid factor (RF), human leukocyte antigen (HLA-B27), and anti-neutrophil cytoplasmic antibody (ANCA). The treatment regimens were adjusted repeatedly according to the patient's clinical symptoms, including prednisone (40mg PO daily), sulfasalazine (3.0mg PO daily), methotrexate (12.5mg PO weekly), thalidomide (100mg PO daily), cyclophosphamide (50mg PO daily) and colchicine (1mg PO daily), etc. In January 2019, the patient's condition worsened with persistent right lower abdominal pain, bloody stools, frequent episodes of oral ulcers, and arthralgia. Colonoscopy showed multiple ulcers in the distal ileum and large protuberant lesions in the cecum and ascending colon ( Figures 1A, B ). The biopsies revealed chronic inflammatory activity of the mucosa with ulcer formation, and no evidence of neoplasia was seen. Considering the patient's recurrent illness, no significant improvement in intestinal mucosal status, and the failure of previous medications, we decided to switch to treatment with anti-TNF-alpha biologics :- infliximab (IFX). We truthfully stated the benefits and risks of using biologics and obtained the informed consent of the patient. IFX was administered with a dose of 300 mg at 0, 2, 6 weeks, and then every eight weeks. The patient reported a significant reduction in oral and vulvar ulcers, abdominal pain, and arthralgia immediately after the first infusion. On August 9, 2019, a colonoscopy showed that the terminal ileal ulcer was better than before. However, there were no significant changes in ileocecal and ascending colon masses. Biopsies revealed acute mucous inflammation, small vessel dilatation and congestion, epithelial hyperplasia on the recessed surface with erosion and inflammatory exudation, and significant glandular hyperplasia and mucus secretion. There was no evidence of granuloma or neoplasia. Intestinal dual-source CT showed obvious thickening at the lower end of ascending colon, soft tissue shadow protruding into the lumen, and abundant blood supply. Endoscopists considered performing endoscopic submucosal dissection (ESD) to be risky. The gastrointestinal surgeon reported that the possibility of colon cancer could not be excluded from the ascending colonic mass and recommended surgical excision to determine its nature. Therefore, after multidisciplinary discussions, the patient underwent a right radical hemicolectomy on September 6, 2019. Post-operative pathology confirmed the mucinous tumor ( Figure 2 ). IFX was suspended. The mFOLFOX6 chemotherapy regimen was administered for four cycles before being discontinued due to the global outbreak of the novel coronavirus. Long-term oral thalidomide (50mg PO daily) to control the disease. In January 2021, the patient's right lower abdominal pain worsened again. Colonoscopy showed multiple large ulcers in the ileum and anastomotic orifice ( Figure 1C ). Enhanced CT of the abdomen showed thickening of the anastomotic wall and the proximal ileal wall of the anastomosis with significant enhancement.
The intestinal BD recurred. The immunosuppressive effect of anti-TNF-alpha biologics may be risky for patients with an oncology history. Therefore, combined with the pathogenesis of intestinal BD and previous case reports, we decided to try VDZ for some clinical benefits. On October 9, 2021, the patient received an infusion of 300 mg VDZ (initially at 0, 2, and 6 weeks, then every eight weeks). After a short follow-up of 6 months, the patient reported that her lower abdominal pain and arthralgia were improved. No obvious adverse reactions occurred. The DAIBD score decreased from 85 to 0, and the WBC, ESR, and CRP levels were normal. On September 30, 2022, a colonoscopy showed a completely healed ileal ulcer with a smooth mucosal surface and well-dilated intestine ( Figure 1D ). However, at the 15th monthly follow-up, her oral and vulvar ulcers recurred, and the CRP concentration increased. Therefore, thalidomide was administered to alleviate systemic inflammation. As shown in  Figures 3A-C , although all systemic inflammatory indices showed repeat increases, such as WBC, CRP, and ESR, these might be caused by the presence of inflammation outside of the gastrointestinal (GI) tract. As only focused on the GI tract ( Figure 3D ), the DAIBD showed the significant efficacy of VDZ on intestinal BD.