Chronic pyloric obstruction caused by Flammulina mushroom: A rare case report.

We report a rare case of chronic pyloric obstruction lasting 4 years. During the endoscopy examination, the cause was found to be foreign matter blocking the pylorus. We assessed the patient's medical history and ultimately considered chronic pyloric obstruction caused by blockage of the Flammulina mushroom.A man in his early 30 presented to the emergency department of the hospital due to recurrent vomiting for 4 years that had aggravated for 2 days.Emergency CT indicated enlargement of the gastric cavity, numerous gastric contents in the gastric cavity, and suspicion of pylorus or duodenal bulb stenosis on imaging. Laboratory findings showed metabolic alkalosis and hypokalemia. When the gastroscope reached the antrum, the endoscopic doctor found a disc-shaped brown object (Flammulina mushroom) in the posterior wall of the posterior antrum.A snare was used to remove the Flammulina mushroom through the endoscopy.The patient's gastric emptying completely resolved, and no vomiting symptoms recurred after 1 month of follow-up.For young men with a history of digestive disease, when gastric retention occurs, doctors are more inclined to diagnose the obstruction caused by the ulcer based on their subjective consciousness. This is a case that did not follow this expectation. Some food without sufficient chewing couldn't be easily digested by gastric acid.