Abstract: Kaposiform hemangioendothelioma （KHE） is a rare borderline vascular tumor   and has a high mortality in infants and young children with Kasabach-Merritt phenomenon （KMP）. Retroperitoneal lesions are rare. A case of retroperitoneal Kaposiform hemangioendothelioma complicated with Kasabach-Merritt and hemorrhagic ascites is reported. A girl aged 3 months presented with considerable reduction of platelets and hemoglobin for a month and progressive enlargement of abdominal circumference for a week， and gastrointestinal bleeding developed on admission to hospital. Laboratory examinations showed fibrin-related markers increased continuously. Platelets and megakaryocytes were easy to find in bone marrow smear. Abdominal CT showed multiple anomalistic and slightly low-density shadows in retroperitoneum and mesentery. Hemorrhagic ascites was drained by peritoneocentesis. Empirical treatment with corticosteroids and immunoglobulin was given with poor effect. Retroperitoneal lesion biopsy as further examination suggested kaposiform hemangioendothelioma which was the final diagnosis. Hemorrhagic ascites was suspected to be associated with Kaposiform hemangioendothelioma. Treatment with corticosteroids，Sirolimus and vincristine was successful，the abnormal laboratory examinations reached normal level，tumor disappeared，and no recurrence was observed for 1 year. For children with intractable thrombocytopenia and persistent coagulation dysfunction，Kasabach-Merritt phenomenon needs to be considered. Imaging examination is necessary to find lesions，and athological biopsy should be done if necessary to help diagnose and select appropriate treatment to improve the prognosis of those children.

Key words: Kaposi form hemangioendothelioma, retroperitoneal, Kasabach-Merritt phenomenon, hemorrhagic ascites, child

摘要： 卡波西样血管内皮瘤（Kaposiform hemangioendothelioma，KHE）是一种罕见的交界性脉管瘤，好发于婴幼儿，易并发致命的卡梅现象（Kasabach-Merritt phenomenon，KMP），腹膜后病灶较少见。该文报道2020年9月14日华中科技大学同济医学院附属同济医院1例腹膜后KHE合并KMP及血性腹水病例，患儿女，3月龄，发现血小板及血红蛋白减少1月余，腹围进行性增大1周，入院时出现消化道出血。实验室检查纤维蛋白相关标志物持续升高，骨髓细胞涂片血小板及巨核细胞易找到；腹部CT示腹膜后及肠系膜多发不规则稍低密度影；腹腔穿刺引流出血性腹水。经验性予以丙种球蛋白、激素治疗后疗效欠佳。进一步完善腹膜后病理活检，确诊为KHE。血性腹水疑与KHE相关。予糖皮质激素、西罗莫司及长春新碱治疗后异常指标恢复，瘤体消失，门诊随访1年无复发。临床上对顽固性血小板降低及持续凝血功能障碍患儿，需考虑KMP可能，积极完善影像学检查寻找病灶，必要时完善病理活检，尽早明确诊断，选择合适治疗，改善患儿预后。

关键词: 卡波西样血管内皮瘤, 腹膜后, 卡梅现象, 血性腹水, 儿童