Department of Nuclear Medicine, The First Affiliated Hospital of Dalian Medical University, Dalian, China.
Department of Nuclear Medicine, Peking University Shen Zhen Hospital, Shen Zhen, China.
Int J Rheum Dis. 2020 Mar;23(3):381-391. doi: 10.1111/1756-185X.13779. Epub 2019 Dec 21.
To update Schall's classification for Sjögren's syndrome (SS) by the new quantitative stimulation test with dynamic salivary glands scintigraphy (qsDSGS) and to standardize quantitative salivary gland scintigraphy.
The histopathology, oral, ocular, serological examination and qsDSGS of 268 consecutive patients with suggestive SS were evaluated in this retrospective cohort study. The serological examination included 15 autoantibodies, antinuclear antibodies (ANA) and so on. The diagnostic thresholds of the functional parameters were set by the quantitative method, and the modified Schall's classification is well established and verified.
Based on the quantitative analysis of qsDSGS, the peak uptake level (PUL) and stimulation excretion fraction (sEF) of each parotid gland were determined as the key imaging features, which had good diagnostic performance for SS. By the modified Schall's classification, all patients were classified into: Class 1 (normal; n = 44), Class 2 (mild to moderate involvement; n = 130), Class 3 (severe involvement; n = 56) and Class 4 (very severe involvement, non-function; n = 38). Using the threshold PUL ≤ 10 counts per sec/pixel as positivity, the modified Schall's classification could provide better diagnostic performance with 88.4% specificity, 71.3% sensitivity, 96.14% positive predictive value and 43.20% negative predictive value for SS (likelihood ratio 6.15). The trends of serologically positive frequencies against SSA/Ro, anti-SSB/La and ANA were significantly increased with the new classification.
The modified Schall's classification by the new stimulation test with dynamic scintigraphy is eligible to standardize quantitative salivary gland scintigraphy for SS, and may be more convenient and suitable in daily practice for clinical research and management of SS.
通过新的动态唾液腺闪烁显像定量刺激试验（qsDSGS）更新 Schall 对干燥综合征（SS）的分类，并使定量唾液腺闪烁显像标准化。
在这项回顾性队列研究中，评估了 268 例疑似 SS 患者的组织病理学、口腔、眼部、血清学检查和 qsDSGS。血清学检查包括 15 种自身抗体、抗核抗体（ANA）等。通过定量方法确定功能参数的诊断阈值，并对改良的 Schall 分类进行了良好的建立和验证。
基于 qsDSGS 的定量分析，确定了每个腮腺的峰值摄取水平（PUL）和刺激排泄分数（sEF）作为关键的成像特征，这些特征对 SS 具有良好的诊断性能。根据改良的 Schall 分类，所有患者分为：1 类（正常；n=44）、2 类（轻度至中度受累；n=130）、3 类（重度受累；n=56）和 4 类（非常严重受累，无功能；n=38）。使用阈值 PUL≤10 计数/秒/像素作为阳性，改良的 Schall 分类可以提供更好的诊断性能，特异性为 88.4%，敏感性为 71.3%，阳性预测值为 96.14%，阴性预测值为 43.20%（比值比 6.15）。SSA/Ro、抗-SSB/La 和 ANA 的血清阳性频率趋势随着新分类显著增加。
通过新的动态闪烁显像刺激试验改良的 Schall 分类有资格使 SS 的定量唾液腺闪烁显像标准化，并且在临床研究和 SS 的管理中可能更方便、更适合日常实践。
