Tuberculosis is a major public health problem that has a huge impact on human health and economic burden. Gastric tuberculosis is a rare type of tuberculosis in various organs of the human body, often secondary to pulmonary tuberculosis, but also secondary to bone tuberculosis, urinary system tuberculosis, and pelvic tuberculosis. Tuberculosis can occur in various parts of the gastrointestinal tract, among which the ileocecal department is the most common, and the stomach is the rarest [4]. The case we reported is a rare multiple gastroduodenal tuberculosis. Mycobacterium tuberculosis invaded the stomach and duodenum, causing damage to the gastrointestinal mucosa, showing ulcer-like changes. Barhausen first reported gastric tuberculosis in 1824, which is a rare disease in western countries[8]. Gastric tuberculosis, like tuberculosis in other parts, mostly occurs in areas with poor living conditions and underdeveloped economies[1]. The age of onset is mostly 20-40 years old. Most gastric tuberculosis occurs in the antrum and pylorus ,which are also a high incidence of peptic ulcers, causing mucosal damage to the gastric antrum and pylorus[9]. Due to ulcers, gastritis damage, erosions or ecchymosis, mucosa ruptures, when TB is swallowed or reaches this part through the blood, it invades the stomach tissue. Mycobacterium tuberculosis infection can invade the stomach in the following ways: 1) Mycobacterium tuberculosis swallowed directly invades the gastric mucosa; 2) Mycobacterium tuberculosis in other parts invades the stomach wall through the blood system or lymphatic system; 3) Mycobacterium tuberculosis infection from nearby organs spreads to stomach. In the case we reported, the patient did not have tuberculosis in his lungs and probably swallowed Mycobacterium tuberculosis which caused gastroduodenal tuberculosis. Infections often lead to gastric and duodenal granuloma formation, caseous necrosis, mucosal ulcers, fibrosis and scarring[10].
Stomach tuberculosis has no unique clinical symptoms. Its clinical manifestations are similar to those of most gastrointestinal diseases. The main manifestations are fever, abdominal pain, bloating, acid reflux, belching, abdominal masses, pyloric obstruction and weight loss, of which ulcerative lesion along the lesser curvature and pylorus is the most common[11]. Stomach tuberculosis can also be combined with gastric ulcer, gastric cancer and other diseases, making the diagnosis more complicated, and it is easy to be misdiagnosed and missed in the diagnosis [12]. In the case we reported, after treatment for acute pancreatitis, abdominal pain of the patient relieved, but he still had prolonged fever. The tuberculosis symptoms are easily masked by acute pancreatitis. The diagnosis of gastroduodenal tuberculosis is a challenge because it has no specific symptoms, no specific radiological and endoscopic features, and mainly relies on gastroscopic biopsy or postoperative pathological examination. Pathological results suggesting that lesions has caseous granuloma or positive staining of acid-fast bacilli is considered to be effective clinical evidence[13]. However, even if a pathological biopsy is performed under a gastroscope, the pathological result of lesions may be non-specific inflammation[14]. Ishii et al. once reported that patients with primary gastric tuberculosis showed negative acid-fast bacilli staining but were effective for empirical ATT[15]. Tuberculous granuloma is more likely to produce negative results, which may be related to the deeper location of tuberculous granuloma[16]. In recent years, various molecular and immunological techniques and other biological techniques have also been increasingly used for rapid diagnosis of gastrointestinal tuberculosis[4]. The study by Baylan et al. showed that acid-fast bacilli staining and biopsy specimens were negative for bacterial culture, while Mycobacterium tuberculosis was positive for polymerase chain reaction (PCR)[17]. Therefore, endoscopists must perform multiple deep resection biopsies, repeated biopsies, and other methods that are most likely to increase the detection rate of tuberculosis according to the characteristics of lesions. Abdominal CT reminds us that the fever and abdominal pain are not only caused by acute pancreatitis. The thickening of the walls of the gastric antrum and duodenum and the enlargement of the surrounding lymph nodes have attracted our attention. Through gastroscopy and biopsy, combined with immunological results such as T-SPOT.TB and anti-tuberculosis antibodies, the diagnosis of the patient was finally clear. The main treatment for gastric tuberculosis is conservative treatment, while anti-tuberculosis treatment is still the main measure. All cases should receive treatment for at least 6 months, and can be extended to 9-12 months if necessary. The standard regimen and the extended regimen consist of isoniazid, rifampicin, pyrazinamide and ethambutol for a period of 2 months, and then continue to give isoniazid and rifampicin until the treatment is completed[4,18]. For poorly treated patients, if there are pyloric obstruction, bleeding, huge ulcers, gastric cancer, etc., surgery can be used to completely remove the lesions.
This disease is clinically rare, and lack of understanding is the main reason for misdiagnosis and missed diagnosis. Patients with multiple ulcers, pyloric obstruction, upper abdominal masses, gastrointestinal bleeding and other symptoms, especially patients with primary tuberculosis and bone tuberculosis, should undergo detailed and systematic examination. Clinicians should improve their understanding of various manifestations of gastric tuberculosis and become familiar with its diagnosis. When gastric tuberculosis is suspected, biopsy should be performed in time and multiple times, and diagnostic tuberculosis treatment is feasible if necessary. Early diagnosis and treatment of gastroduodenal tuberculosis can help reduce the occurrence of complications.