Etiology: Primary intestinal tuberculosis is rare, usually due to the consumption of milk contaminated with bovine tuberculosis bacteria. Secondary intestinal tuberculosis mostly originates from pulmonary tuberculosis, and the route of infection is mainly through the ingestion of sputum containing large amounts of tuberculosis bacteria by patients with active tuberculosis. In addition to direct invasion of the gastrointestinal tract, intestinal tuberculosis can also be infected via the bloodstream. This is mostly seen in cornified tuberculosis and advanced pulmonary tuberculosis. In this case, the patient had double pulmonary TB and the route of infection most likely originated from pulmonary TB. After being ingested, the bacilli are mostly not killed by gastric acid because of their lipid-containing outer membrane. When the bacilli reach the ileocecal region, the food containing Mycobacterium tuberculosis has become chyme, which has a greater chance to contact the intestinal mucosa directly. In addition, there is abundant lymphatic tissue in the ileocecal region, which has a strong susceptibility to tuberculosis. In this case, the main lesion site was in the ileum, and there were multiple foci of caseous necrosis in the mesentery of the perineum. Diagnosis: The incidence of intestinal tuberculosis is low, and the clinical manifestations are varied and non-characteristic. X-ray abdominal plain film may show calcification in a few patients. Barium meal or enema: When the barium reaches the lesion site, the intestinal movement increases and the barium passes rapidly, making the filling of the lesion site unsatisfactory. Sometimes the filling is not uniform due to intestinal spasm. This type of intestinal tuberculosis must be distinguished from Crohn’s disease and ulcerative colitis. Proliferative intestinal tuberculosis mostly manifests as chronic incomplete low intestinal obstruction, so abdominal X-ray plain film can be seen as small intestine distension, intestinal curvature dilatation, accompanied by gas and liquid flat. Barium meal or barium irrigation can be seen as intestinal tube deformation, stiffness or shortening, and disappearance of colonic pouch. Irregular barium filling defect is common in the ileocecal region. The first clinical manifestation of this patient was intestinal obstruction, and the surgical exploration revealed abdominal abscess and caseous necrotic lesions, which should be considered as intestinal tuberculosis. Anti-tuberculosis chemotherapy: There are more than ten kinds of anti-tuberculosis drugs. It is generally believed that anti-tuberculosis drugs can be divided into two categories: bactericidal drugs and antibacterial drugs. Some people are also accustomed to classify drugs with strong antibacterial effects and few side effects as first-line drugs, while the rest are classified as second-line drugs. The clinical use of drugs should adhere to the principles of early, combined, appropriate, regular and full use of sensitive drugs, and the chemotherapy regimen depends on the severity of the disease. At present, in order to enable patients to recover early and prevent the development of drug resistance, short-course chemotherapy is mostly used, with a duration of 6 to 9 months. The combination of two bactericidal drugs, isoniazid and rifampicin, is generally used. In the first 1-2 weeks of treatment, there is improvement of symptoms, increase of appetite, and normalization of body temperature and stool properties. For severe intestinal tuberculosis, or with severe extraintestinal tuberculosis, it is appropriate to add pyrazinamide or ethambutol in combination for 12 months. In this case, the combination of isoniazid, rifampin, and pyrazinamide was used, and the lung lesions were absorbed more quickly. Pay attention to clinical observation and review of liver and kidney function when applying anti-tuberculosis drugs, and promptly adjust the drugs in case of abnormalities. Timing of surgery: Intestinal tuberculosis is mainly treated with internal antituberculosis drugs and systemic supportive therapy. Patients with active tuberculosis should not be treated surgically. Because anesthesia can lead to the spread of pulmonary tuberculosis, surgery can lead to the spread of abdominal tuberculosis if the intestinal tuberculosis lesion is not completely removed. If possible, a period of antituberculosis and systemic supportive therapy should be administered before surgery. In this case, the patient was severely malnourished and had bilateral pulmonary infiltrative tuberculosis at the time of surgical admission to our hospital. Moreover, the intestinal canal was obviously edematous and adherent, with multiple intestinal fistulas, making surgery very difficult. We adopted continuous negative pressure suction of intestinal fluid on the basis of anti-tuberculosis and systemic supportive therapy, and then intubated the intestinal fluid back from the most distal intestinal fistula. When the tuberculosis lesion of the lung is basically absorbed, the edema of the intestinal canal is obviously subsided before preparing for surgery. Surgical approach : The principle of surgical treatment should be to remove the diseased intestinal segment as much as possible, repair the intestinal fistula and relieve the intestinal obstruction. In this case, it was very difficult for the patient to enter the abdominal cavity. We adopted the approach of extending the original surgical incision, separating the adhesions between the abdominal wall and the intestinal canal from the parts with lighter adhesions, gradually separating all the small intestinal adhesions, clarifying the anatomical relationships, and removing as much of the abdominal tuberculosis lesions as possible. The small intestinal fistula was repaired with sutures, and the part of the intestinal canal with obvious lesions and stenosis was resected. In this case, the patient had normal stool with daily return of intestinal fluid from the distal intestinal canal before surgery, so it was safe to anastomose with the distal intestinal canal. After the anastomosis, the anastomosis was examined for no tension, no stricture, and good blood supply. Due to extensive abdominal adhesions, there was more exudation after surgical separation. We placed drains in the bilateral lower abdomen and closed them with tension sutures in full tension reduction. The sutures were removed only 4 weeks after surgery to prevent wound dehiscence. The result was good wound healing.