CT检查对儿童朗格汉斯细胞组织细胞增生症胸腺受累诊断价值

Role of CT in the diagnosis of the thymus involvement in children with LCH

目的朗格汉斯细胞组织细胞增生症(Langerhans cell histiocytosis,LCH)易累及胸腺。本研究分析儿童胸腺受累CT表现特征及诊断价值。方法收集华中科技大学同济医学院附属武汉儿童医院2011-01-01-2018-03-30经确诊的44例LCH患儿资料,分为单系统-LCH(single-system langerhans cell histiocytosis,SS-LCH)21例和多系统-LCH(multi-system langerhans cell histiocytosis,MS-LCH)23例。回顾分析41例初诊及32例随访胸部CT影像学资料。结果18例胸部受累均见于MS-LCH,胸腺受累11例,肺部受累18例,胸腺+肺部同时受累9例。胸腺CT表现,7例见点状或小片状钙化,其中2例并小片状或囊状低密度影;2例见小片状或囊状低密度影,增强后更明显;2例平扫胸腺有增大,疑有占位效应,密度基本均匀,增强后见多发散在小片状或囊状低密度影。治疗后复查,32例胸腺体积均有缩小,包括治疗前正常和异常的胸腺;2例钙化减少至消失。肺部CT表现,10例肺部见小气囊影、结节影、蜂窝肺及细网织样间质改变,其中6例并胸腺异常;4例轻度磨玻璃样;4例少许炎症。19例MS-LCH患儿免疫功能异常。结论儿童LCH胸腺异常见于MS-LCH,同时存在免疫功能紊乱。胸腺CT最具有特征性影像表现是多发散在点状或小片状钙化影,并(或)多发小片状或囊状低密度影,增强后病灶显示更明显。若同时并肺部典型间质改变,提高了LCH影像诊断价值。

OBJECTIVE LCH is also prone to attacking the thymus gland,this study aims to investigate the CT im- aging findings and diagnostic value of thymus gland in children with LCH. METHODS Totally 44 cases（SS-LCH 21 and MS -LCH 23）with LCH confirmed by clinical diagnosis were collected from Wuhan Children＇s Hospital, Tongji Medical College,Huazhong University of Science＆Teehnology （2011 01-01-2018 03 30）. CT imaging of chest in children with LCH were retrospectively analyzed,including pre-therapy 41 cases and post-treatment 32cases. RESULTS Totally 18 cases with thoracic involvement were classified as group MS-LCH,including 11 cases＇ thymus gland and 18 cases＇ lung. Nine cases＇ thymus gland and lung were involved simultaneously. CT imaging of the thymus included the following：7 ca- ses with punctiform or patchy calcification, complicated with patchy or cystic shadow in 2 cases;2 cases with patchy or cystic shadow more obvious after contrast enhancement;2 cases with thymus enlargement, suspicion of space-occupying le- sion and even density in plain CT,but multiple,scattered,patchy or cystic shadow occurring after contrast enhancement. Totally 32 cases of the thymus volume of post-treatment were all smaller than pre-therapy,including pre-therapy normal and abnormal thymus. Two cases of thymus calcification decreased or faded away after treatment. CT imaging the lung showed the pulmonary interstitial lesions such as small balloon shadow, nodules shadows, boneycomb lung and reticular changes in 10 cases （6 cases with abnormal thymus） ,mild ground class shadow in 4 cases,a little inflammation in 4 cases. Totally 19 cases with MS LCH had abnormal immune function. CONCLUSIONS The abnormal thymus is more common in children with MS LCH ,eompanying with immune dysfunction. The most common CT findings on the abnormal thymusgland are finely calcifications, and（or） small flake or cystic low density, more obvious after contrast enhancement. The ab- normal thymus gland with the pulmonary interstitial lesion helps to improve imaging diagnosis of LCH.