Diagnostic accuracy of enthesis ultrasound in the diagnosis of early spondyloarthritis.

de Miguel E, Muñoz-Fernández S, Castillo C, Cobo-Ibáñez T, Martín-Mola E.

Source

Correspondence to Dr Eugenio de Miguel, Rheumatology Unit, Hospital Universitario La Paz, Pº de la Castellana 261, 28046 Madrid, Spain. eugenio.demiguel@gmail.com

Abstract

OBJECTIVE:

To determine the sensitivity and specificity of enthesis ultrasound for the diagnostic classification of early spondyloarthritis.

METHODS:

A cross-sectional, blinded and controlled study. Standardised bilateral ultrasound of six entheses (Madrid sonography enthesitis index (MASEI)) was performed. Accepted diagnostic classification criteria were used as the gold standard. Validity was analysed by receiver operating characteristic (ROC) curves. Values of p<0.05 were considered significant.

RESULTS:

113 early spondyloarthritis patients were included (58 women/55 men), 57 non-inflammatory control individuals (29 women/28 men) and 24 inflammatory control individuals (11 women/13 men). The evolution time of spondyloarthritis was 10.9±7.1 months. At least some grade of sacroiliitis on x-ray was present in 59 patients, but only five fulfilled the radiographic sacroiliitis New York criteria. Human leucocyte antigen B27 (HLA-B27) was positive in 42% of patients. No statistical differences were found for the enthesis score among diagnostic spondyloarthritis subtypes form of presentation (axial, peripheral or mixed) or HLA-B27 positivity. The MASEI score achieved statistical significance for gender. The ultrasound score was 23.36±11.40 (mean±SD) in spondyloarthritis patients and 12.26±6.85 and 16.04±9.94 in the non-inflammatory and inflammatory control groups (p<0.001), respectively. The ROC area under the curve was 0.82, and a cut-off point of ≥20 points achieved a likelihood ratio of 5.30 and a specificity of 89.47%.

CONCLUSIONS:

Entheses are affected early in spondyloarthritis, and the incidence of involvement is higher in men and independent of the spondyloarthritis diagnostic subtype, HLA-B27 status or presentation pattern. The enthesis ultrasound score seems to have diagnostic accuracy and may be useful for improving the diagnostic accuracy of early spondyloarthritis.

PMID: 21131646

超声检查附着点在早期SpA诊断中的应用

de Miguel E, et al. Ann Rheum Dis. 2011. 70:434-9

目的：确定超声检测附着点炎对于诊断早期脊柱炎(SpA)的敏感性和特异性。

方法：采用一项横断面、盲法对照研究。采用标准超声操作，检查双侧6对附着点（马德里超声附着点炎指数，MASEI））。采用公认的诊断分类标准作为金标准。采用受试者工作特征曲线（ROC）对有效性进行分析。统计学显著性的P值定位小于<0.05。

结果：纳入113早期SpA患者（58例女性/55例男性），以57例非炎症疾病患者（29 例女性/28例男性）以及24例炎症疾病患者（11例女性/13例男性）作为对照。SpA病程为10.9±7.1个月。59例骶髂关节炎的X线摄片有异常发现，但仅有5例达到纽约修订版分类标准所规定的病变级别。HLA-B27阳性率为42％。在SpA的各亚型病人(中轴型、外周型或混合型)中，附着点炎评分并无统计学差异。不同性别患者的MASEI评分存在统计显著性差异。SpA病人附着点炎评分为23.36±11.40（平均值±SD），非炎症对照组和炎症对照组分别为12.26 ± 6.85和16.04 ± 9.94（P 值均小于0.001）。 ROC曲线下面积为0.82，如将超声附着点炎评分界限值定为≥20分，那么诊断Spa的似然比为5.30，诊断特异性为89.47％。

结论：在SpA病程早期就会出现附着点炎，男性受累发生率较高，与SpA亚型、HLA-B27是否阳性以及目前疾病表现类型无关。超声检查附着点炎的准确性似乎尚可，可能有助于改善早期SpA诊断的准确性。