Department of Pediatrics, Division of Rheumatology, Alberta Children's Hospital, University of Calgary, 2888 Shaganappi Trail NW Calgary, AB T3B 6A8, Canada.
Rheumatology (Oxford). 2011 May;50(5):885-93. doi: 10.1093/rheumatology/keq407. Epub 2010 Dec 13.
To investigate the longitudinal association of nailfold capillary density (NCD; as a potential marker of activity) with various other clinical measures of disease activity and to evaluate baseline NCD as a predictor of disease outcome in children with JDM.
Data from 809 clinic visits from 92 JDM patients were prospectively collected at each clinic visit over a time period of 5.5 years. The number of capillaries per millimetre at the distal nailfold was scored using a stereomicroscope. Disease activity was determined using the Childhood Myositis Assessment Scale (CMAS) and a modification of the validated disease activity score (DAS), which included three skin (SDAS) and three muscle (MDAS) criteria. An inception cohort subgroup (n=28) with a baseline visit at diagnosis was analysed separately.
Both DAS subscores, MDAS (β = -0.04437, P < 0.0001) and SDAS (β = -0.1589, P < 0.0001), as well as the CMAS (β = 0.02165, P < 0.0001) were significantly associated with loss of end row nailfold capillary over time (multiple regression mixed-model analysis). All patients in the inception subcohort showed a reduced baseline NCD (diagnostic sensitivity = 100%) that improved as the disease improved, but this did not predict longer term outcome or course of disease.
NCD is a marker of skin and muscle disease activity, and is an important measure of disease activity changes from visit to visit. Determination of capillary density may be useful when making treatment decisions. A decrease in NCD may be considered for inclusion in the diagnostic criteria due to its high sensitivity.
研究甲襞毛细血管密度（NCD；作为活动的潜在标志物）与其他各种疾病活动临床指标的纵向关联，并评估基线 NCD 作为儿童 JDM 疾病结局的预测因子。
在 5.5 年的时间内，前瞻性地从 92 例 JDM 患者的 809 次就诊中收集数据。使用立体显微镜对远端甲襞每毫米的毛细血管数量进行评分。使用儿童肌炎评估量表（CMAS）和经过验证的疾病活动评分（DAS）的修改版来确定疾病活动度，该评分包括三个皮肤（SDAS）和三个肌肉（MDAS）标准。单独分析了一个具有基线就诊的起始队列亚组（n=28）。
DAS 两个亚分，MDAS（β= -0.04437，P<0.0001）和 SDAS（β= -0.1589，P<0.0001），以及 CMAS（β= 0.02165，P<0.0001）与随时间推移丢失末行甲襞毛细血管呈显著相关（多元回归混合模型分析）。起始亚组中的所有患者的基线 NCD 均降低（诊断灵敏度=100%），随着疾病的改善而改善，但这并不能预测长期结局或疾病过程。
NCD 是皮肤和肌肉疾病活动的标志物，是评估每次就诊时疾病活动变化的重要指标。确定毛细血管密度可能有助于在治疗决策时做出决定。由于其高灵敏度，NCD 的减少可考虑纳入诊断标准。
