[Duodenal obstruction and upper gastrointestinal bleeding as the initial presentation of an isolated duodenal tuberculosis].

Primary duodenal tuberculosis is rare, even in endemic regions. The diagnosis poses a major challenge and requires a high index of suspicion, supported by imaging studies, microbiology, and histopatology obtained by endoscopic or surgical biopsy. We report the case of a 31-year-old man, without HIV infection or any previous history of tuberculosis, who presented with duodenal obstruction. After exploratory laparotomy, he presented a duodenal stenosis and upper gastrointestinal bleeding. A total of four diagnostic procedures (one laparotomy and three endoscopies) were performed, all of which included biopsies. Only the last endoscopy made with the technique "biopsy upon biopsy" showed the presence of acid fast bacilli and granulomas. The diagnosis of tuberculosis was confirmed by polymerase chain reaction in duodenal tissue. There was no evidence of involvement of other organs by tuberculosis. The patient had an excellent therapeutic response.