AIM To analyze the clinical characteristics of eosinophilic gastroenteritis(EGE)and to investigate the situations of missed diagnosis of EGE.METHODS First,the clinical characteristics of 20 EGE patients who were treated at our hospital were retrospectively summarized.Second,159 patients who underwent gastroscopy and 211 patients who underwent colonoscopy were enrolled.The pathological diagnosis showed only chronic inflammation in their medical records.The biopsy slides of these patients were reevaluated to determine the number of infiltrating eosinophils in order to assess the probability of a missed diagnosis of EGE.Finally,122 patients who experienced refractory upper gastrointestinal symptoms for at least one month were recruited.At least 6biopsy specimens were obtained by gastroscopy,and the number of eosinophils that had infiltrated was evaluated.Those who met the pathological diagnostic criteria of EGE underwent further examination to confirm the diagnosis of EGE.The probability of a missed diagnosis of EGE was prospectively investigated.RESULTS Among the 20 patients with EGE,mucosal EGE was found in 15 patients,muscular EGE was found in 3patients and serosal EGE was found in 2 patients.Abdominal pain was the most common symptom.The number of peripheral blood eosinophils was elevated in all 20 patients,all of whom were sensitive to corticosteroids.Second,among the 159 patients who underwent gastroscopy,7(4.40%)patients met the criteria for pathological EGE(eosinophil count≥25/HPF).Among the 211 patients who underwent colonoscopy,9(4.27%)patients met the criteria for pathological EGE(eosinophil count≥30/HPF).No patients with eosinophil infiltration were diagnosed with EGE in clinical practice before or after endoscopy.Although these patients did not undergo further examination to exclude other diseases that can also lead to gastrointestinal eosinophil infiltration,these might be the cases where the diagnosis of EGE was missed.Finally,among the 122 patients with refractory upper gastrointestinal symptoms,eosinophil infiltration was seen in 7 patients(5.74%).The diagnosis of EGE was confirmed in all 7 patients after the exclusion of other diseases that can also lead to gastrointestinal eosinophil infiltration.A positive correlation was observed between the duration of the symptoms and the risk of EGE(r=0.18,P<0.01).The patients whose symptoms persisted longer than 6 mo more readily developed EGE.None of the patients were considered to have EGE by their physicians before endoscopy.CONCLUSION Although EGE is a rare inflammatory disorder,it is easily misdiagnosed.When a long history of abdominal symptoms fails to improve after conventional therapy,EGE should be considered. AIM To analyze the clinical characteristics of eosinophilic gastroenteritis (EGE) and to investigate the situations of missed diagnosis of EGE. METHODS First, the clinical characteristics of 20 EGE patients who were treated at our hospital were retrospectively.Second, 159 patients who underwent gastroscopy and 211 patients who underwent colonoscopy were enrolled.The pathological diagnosis showed only chronic inflammation in their medical records.The biopsy slides of these patients were reevaluated to determine the number of infiltrating eosinophils in order to assess the probability of a missed diagnosis of EGE.Finally , 122 patients who experienced refractory upper gastrointestinal symptoms for at least one month were recruited. At least 6 biopsy specimens were obtained by gastroscopy, and the number of eosinophils that had infiltrated was evaluated. Who ensed the pathological diagnostic criteria of EGE underwent further examination to confirm the diagnosis of EGE. probability of a missed diagnosis of EGE was prospectively investigated .RESULTS Among the 20 patients with EGE, mucosal EGE was found in 15 patients, muscular EGE was found in 3patients and serosal EGE was found in 2 patients. Abdominal pain was the most common symptom. number of peripheral blood eosinophils was elevated in all 20 patients, all of whom were sensitive to corticosteroids. Second, among the 159 patients who underwent gastroscopy, 7 (4.40%) patients met the criteria for pathological EGE (eosinophil count ≥ 25 / HPF) .Among the 211 patients who underwent colonoscopy, 9 (4.27%) patients met the criteria for pathological EGE (eosinophil count ≥30 / HPF) .No patients with eosinophil infiltration were diagnosed with EGE in clinical practice before or after endoscopy .Although these patients did not Yet further examination to exclude other diseases that can also lead to gastrointestinal eosinophil infiltration, these might be the cases where the diagnosis of EGE was missed. Finally, among the 122 patients withrefractory upper gastrointestinal symptoms, eosinophil infiltration was seen in 7 patients (5.74%). The diagnosis of EGE was confirmed in all 7 patients after the exclusion of other diseases that can also lead to gastrointestinal eosinophil infiltration. A positive correlation was observed between the duration of the symptoms and the risk of EGE (r = 0.18, P <0.01). The patients whose symptoms persisted longer than 6 mo more readily developed EGE. None of the patients were considered to have EGE by their physicians before endoscopy. CONCLUSION Although EGE is a rare inflammatory disorder, it is easily misdiagnosed. After a long history of abdominal symptoms fails to improve after conventional therapy, EGE should be considered.