目的：探讨炎性髓系肿瘤Erdheim-Chester病（Erdheim-Chester disease，ECD）患者的临床及影像学特征。方法：回顾性分析2019年3月至2022年2月上海交通大学附属瑞金医院经病理证实的6例ECD患者的临床及影像学资料。结果：6例ECD患者的年龄为11~64岁，其中4例患者的年龄为11~33岁，较年轻；男女比例为2∶1，临床症状以中枢性尿崩（2例）、共济失调（2例）、下肢疼痛（3例）以及眼眶周黄色斑块（3例）为主要特点。6例患者中5例累及骨骼系统；6例均累及骨骼外系统，包括累及皮肤和皮下软组织5例，累及中枢神经系统2例，累及心血管系统2例，累及胸部2例（其中1例伴有肺腺癌），腹膜后巨大肿块和肾脏纤维化改变各1例。6例患者在影像诊断为ECD 2例、眼部黄色肉芽肿1例、其他3例影像不能进行病因诊断。6例患者中2例临床误诊为恶性肿瘤，但未能明确疾病类型。1例初次行X线检查双下肢假阴性，经CT检查后发现骨质硬化性改变。ECD患者的骨骼系统特征性X线和CT表现为，双侧上下肢骨质硬化，其中1例为下肢对称性，1例为左上肢骨质硬化；非特征性X和CT表现溶骨性骨质破坏，其中1例为颞下颌关节和2例为上颌骨。骨骼外多系统病变（6例）表现为密度、信号、放射性浓聚异常。随访提示，2例预后良好，1例死亡，3例疾病进展。结论：ECD患者多以中枢性尿崩及共济失调为主要症状，伴皮肤黄色肉芽肿及其他皮肤病变等临床特征。影像学表现主要为双下肢骨质硬化，同时伴有全身其他系统多发病变。

Objective: To investigate the clinical and imaging characteristics of an inflammatory myeloid neoplasm-- Erdheim-Chester disease (ECD). Methods: The clinical and imaging data from 6 patients with pathology -confirmed ECD visited Ruijin Hospital, Shanghai Jiao Tong University during March 2019 to February 2022 were retrospectively analyzed. Results: The age of 6 ECD patients ranged from 11 to 64 years, of which 4 were young, aged 11 to 33 years. The ratio of male to female was 2∶1. The main symptoms were central diabetes insipidus（2 cases）, ataxia（2 cases）, lower limb pain （3 cases）and periorbital yellow plaques （3）. The skeletal system was involved in 5 of 6 cases. All 6 cases involved extra-skeletal systems, including skin and subcutaneous soft tissue (n=5), central nervous system (n=2), cardiovascular system (n=2), chest (n=2, including 1 with lung adenocarcinoma), retroperitoneal mass (n=1) and renal fibrosis (n=1).Among 6 cases of ECD, 2 cases were diagnosed as ECD on the imaging, and 1 case as xanthogranuloma in the eye, and 3 other cases that could not tell on the imaging. For clinical diagnosis,2 patients were clinically misdiagnosed as having malignant tumors, but the disease type was not clearly identified. A case with false negative result in both lower limbs on initial X-ray imaging, and CT examination showed bone sclerosis. In patients with ECD, the characteristic X-ray and CT findings of the skeletal system were symmetric bone sclerosis of the long bones of both upper and lower limbs, while non-characteristic X-ray and CT findings were osteolytic bone destruction. Multiple extra-skeletal lesions showed abnormalities in density, signal and radioactivity concentration. Conclusions: Erdheim-Chester disease usually presents with central diabetes insipidus and ataxia, accompanied by cutaneous xanthogranuloma and other skin lesions. The main imaging manifestation of ECD is osteosclerosis of both lower extremities, with multiple system involvement.