Objective:In order to improve the understanding of the clinical, endoscopic and pathological characteristics of occult primary intestinal lymphangiectasia in infants, and to reduce misdiagnosis and missed diagnosis, we analyzed the clinical manifestations and diagnosis and treatment related data of a case of primary intestinal lymphangitis in Xiamen Children′s Hospital.The patient was admitted to the hospital with bronchopneumonia, mild diarrhea and edema, without decreasing in the number of peripheral blood lymphocytes, showing hypoproteinemia.Albumin infusion failed to alleviate hypoalbuminemia, and then gastroscopy showed that the duodenal segment had white millet like granular protrusion with different sizes and dense density, and the mucosa had extensive leukoplakia like lesions.Pathological examination showed that the small intestinal lymphadenectasia was obvious, and then the small intestinal lymphadenectasia was confirmed.After diagnosis, albumin was infused every two days for two consecutive courses and portagen medium chain fatty acid milk powder was fed.After treatment, the total protein and albumin in the plasma basically rose to the normal level, and the color Doppler ultrasonography of abdomen and chest showed that both pleural effusion and bilateral pulmonary effusion had been absorbed.The retrospective analysis of this case shows that for infants with dropsy caused by the decrease of plasma albumin and globulin, the possibility of excessive protein consumption caused by liver and kidney disease, tumor, tuberculosis and other chronic diseases should be excluded, and small intestinal lymphadenopathy should be considered, gastroscopy should be performed as soon as possible, pathological biopsy should be further improved, early diagnosis and treatment should be carried out as soon as possible And diet intervention treatment to avoid serious consequences caused by not timely handling.