Varsani Hemlata, Charman Susan C, Li Charles K, Marie Suely K N, Amato Anthony A, Banwell Brenda, Bove Kevin E, Corse Andrea M, Emslie-Smith Alison M, Jacques Thomas S, Lundberg Ingrid E, Minetti Carlo, Nennesmo Inger, Rushing Elisabeth J, Sallum Adriana M E, Sewry Caroline, Pilkington Clarissa A, Holton Janice L, Wedderburn Lucy R
Rheumatology Unit, UCL Institute of Child Health, London, UK.
Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, UK.
Ann Rheum Dis. 2015 Jan;74(1):204-10. doi: 10.1136/annrheumdis-2013-203396. Epub 2013 Sep 24.
To study muscle biopsy tissue from patients with juvenile dermatomyositis (JDM) in order to test the reliability of a score tool designed to quantify the severity of histological abnormalities when applied to biceps humeri in addition to quadriceps femoris. Additionally, to evaluate whether elements of the tool correlate with clinical measures of disease severity.
55 patients with JDM with muscle biopsy tissue and clinical data available were included. Biopsy samples (33 quadriceps, 22 biceps) were prepared and stained using standardised protocols. A Latin square design was used by the International Juvenile Dermatomyositis Biopsy Consensus Group to score cases using our previously published score tool. Reliability was assessed by intraclass correlation coefficient (ICC) and scorer agreement (α) by assessing variation in scorers' ratings. Scores from the most reliable tool items correlated with clinical measures of disease activity at the time of biopsy.
Inter- and intraobserver agreement was good or high for many tool items, including overall assessment of severity using a Visual Analogue Scale. The tool functioned equally well on biceps and quadriceps samples. A modified tool using the most reliable score items showed good correlation with measures of disease activity.
The JDM biopsy score tool has high inter- and intraobserver agreement and can be used on both biceps and quadriceps muscle tissue. Importantly, the modified tool correlates well with clinical measures of disease activity. We propose that standardised assessment of muscle biopsy tissue should be considered in diagnostic investigation and clinical trials in JDM.
研究青少年皮肌炎（JDM）患者的肌肉活检组织，以测试一种旨在量化组织学异常严重程度的评分工具在肱二头肌以及股四头肌上应用时的可靠性。此外，评估该工具的各项指标是否与疾病严重程度的临床指标相关。
纳入55例有肌肉活检组织且有临床数据的JDM患者。活检样本（33例股四头肌，22例肱二头肌）按照标准化方案制备并染色。国际青少年皮肌炎活检共识小组采用拉丁方设计，使用我们之前发表的评分工具对病例进行评分。通过组内相关系数（ICC）和评分者一致性（α）来评估可靠性，评估评分者评分的差异。最可靠工具项目的评分与活检时疾病活动的临床指标相关。
许多工具项目的观察者间和观察者内一致性良好或较高，包括使用视觉模拟量表对严重程度进行总体评估。该工具在肱二头肌和股四头肌样本上的功能同样良好。使用最可靠评分项目的改良工具与疾病活动指标显示出良好的相关性。
JDM活检评分工具具有较高的观察者间和观察者内一致性，可用于肱二头肌和股四头肌肌肉组织。重要的是，改良工具与疾病活动的临床指标相关性良好。我们建议在JDM的诊断研究和临床试验中应考虑对肌肉活检组织进行标准化评估。
