Acute gastroenteritis with bacterial infection can cause fecal occult blood. A positive fecal occult blood test means that red blood cells are detected in the stool routine, which refers to a small amount of bleeding in the digestive tract, where the red blood cells are destroyed by digestion, and there is no abnormal change in the appearance of the feces, which cannot be confirmed by the naked eye or microscope. It can be seen in acute gastroenteritis, acute gastritis, gastrointestinal tumors, peptic ulcer and so on. Bacterial infection of acute gastroenteritis can lead to pathological changes such as congestion, edema, erosion, and even ulceration of the gastrointestinal mucosa, and there can be red blood cells in the stool, which leads to a positive fecal occult blood test. Bacterial infection of acute gastroenteritis may have diarrhea, abdominal pain, nausea, vomiting and other symptoms, the diagnosis is mainly rely on the history, symptoms, stool routine, stool culture, blood routine and other tests. Bacterial infection of acute gastroenteritis can cause fecal occult blood, it is recommended that people with positive fecal occult blood test actively consult the doctor, improve the examination, clarify the diagnosis and symptomatic treatment.