[Clinical features of 50 patients with primary intestinal lymphangiectasia].

<b>Objective:</b> To investigate the clinical features of primary intestinal lymphangiectasia (PIL). <b>Methods:</b> This study was a retrospective case series study. Fifty consecutive patients diagnosed with PIL in Department of Lymphatic Surgery, Beijing Shijitan Hospital, Capital Medical University from March 2019 to March 2021 were included and their clinical data was retrospectively reviewed. There were 20 males and 30 females included, with an age of (<i>M</i>(IQR)) 14 (40) years (range:0 to 67 years). No patient had the family history. There were 26 children, including 9 males and 17 females, aged 0 (7) years (range:0 to 14 years). There were 24 adults, including 11 males and 13 females, aged 40 (26) years (range:20 to 67 years). The clinical manifestations and the results of laboratory examinations, gastrointestinal endoscopy, ⁹⁹Tc^m-labeled human albumin (⁹⁹Tc^m-HSA) scintigraphy, ⁹⁹Tc^m-DX scintigraphy, direct lymphangiography (DLG), histopathology, diet treatment, surgical intervention, and clinical symptom remission at discharge were collected. Comparisons between groups were performed using independent samples <i>t</i>-test, Mann-Whitney <i>U</i> test, or <i>χ</i> ² test. <b>Results:</b> Among the 50 cases of PIL, the main manifestations were edema (86.0%), diarrhea (76.0%), and abdominal effusion (48.0%). Lymphedema (36.0%) and chylous ascites (18.0%) were not rare in PIL patients. In ⁹⁹Tc^m-HAS scintigraphy, 95.9% (47/49) cases showed signs of intestinal protein loss, and 91.7% (44/48) ceses showed positive findings in ⁹⁹Tc^m-DX scintigraphy. In DLG, 97.8% (45/46) cases showed signs of thoracic duct obstruction, 82.6% (38/46) cases showed retroperitoneal lymphatic hyperplasia, and 23.9% (11/46) cases showed backflow of contrast agent into intestine. No significant difference was seen in gender, course of disease, clinical manifestation, serum level of albumin or globulin, lymphocyte count, positive rate of fecal occult blood and prevalence of lymphedema between adults and children (all <i>P</i>>0.05). <b>Conclusions:</b> The clinical presentations of PIL between children and adults had no significant difference. The diagnosis of PIL should be made according to clinical manifestation, ⁹⁹Tc^m-HAS scintigraphy, ⁹⁹Tc^m-DX scintigraphy, DLG, gastrointestinal endoscopy and pathological findings.