编者：高洁，西京医院临床免疫科

目  的：

皮下受累包括钙质沉着症和脂膜炎，是幼年皮肌炎(JDM)比成人皮肌炎更常见的并发症。磁共振成像（MRI）有助于评估疾病的分布。我们研究了JDM患者皮下受累的临床意义。

方  法：

应用脂肪抑制磁共振成像对18例新诊断的JDM患者的大腿和臀部进行评估。根据MRI上双侧肌肉、筋膜和皮下脂肪受累程度从0分到8分进行评分。评估临床表现、血清肌酸肌酶和MRI评分之间的关系。

结  果：

本文报告分别有18例、18例和10例患者存在肌肉、筋膜和皮下脂肪的MRI异常表现。早期诊断JDM患者（发病后不到2个月）的皮下脂肪评分显著高于晚期诊断JDM患者（晚诊断）（p=.025）。所有患者血清醛缩酶均升高，但只有8例显示血清肌酸磷酸激酶升高。血清醛缩酶与皮下脂肪MRI评分(p<0001,ρ=.787)及筋膜评分(p=.013ρ=0.574)呈显著正相关,与肌肉评分无显著相关性。此外，血清醛缩酶与血清甘油三酯显著相关（p=.009，ρ=0.629）。

结  论：

皮下脂肪受累是早期诊断JDM的一个特征性发现，且与血清醛缩酶升高有关。

文献来源：

Mod Rheumatol. 2018 Oct 18:1-6. doi:10.1080/14397595.2018.1511026. [Epub ahead of print]

Clinical significance of subcutaneous fat and fascialinvolvement in juvenile dermatomyositis

OBJECTIVES:

Subcutaneous involvement,including calcinosis and panniculitis, is a more common complicationin juveniledermatomyositis (JDM) than in adult dermatomyositis.Magnetic resonance imaging (MRI) is useful for evaluating disease distribution.We investigated the clinical significance of subcutaneous involvement in JDM.

METHODS:

Thighs and hips in 18 newly diagnosed JDMpatients were evaluated with fat-suppression MRI. Bilateral muscle, fascial andsubcutaneous fat involvement were scored from 0 to 8 points according to theseverity of distribution on MRI. Associations between clinical manifestations,serum muscle enzymes, and MRI scores were also evaluated.

RESULTS:

Abnormal MRI findings in muscle, fascia andsubcutaneous fat were observed in 18, 18, and 10 patients, respectively.Subcutaneous fat scores were significantly higher in early-diagnosed JDMpatients (diagnosed less than 2 months from onset) than in late-diagnosed JDMpatients (diagnosed later) (p = .025). Serum aldolase was elevated in allpatients, although only eight demonstrated elevated serum creatinephosphokinase. Serum aldolase was significantly correlated with MRI scores forsubcutaneous fat (p < .0001, ρ = .787) and fascia (p = .013 ρ = 0.574), butnot muscle. Additionally, serum aldolase was significantly correlated withserum triglycerides (p = .009, ρ = 0.629).

CONCLUSION:

Subcutaneous fat involvement is a characteristicfinding in early-diagnosed JDM and correlates with elevated serum aldolase.