Diagnostic value of salivary gland ultrasonographic scoring system in primary Sjogren's syndrome: a comparison with scintigraphy and biopsy.

ABSTRACT

OBJECTIVE: To compare an ultrasonographic (US) scoring system of salivary glands with scintigraphy and salivary gland biopsy, in order to evaluate its diagnostic value in primary Sjögren's syndrome (SS). METHODS: In 135 patients with suspected SS, the grades of 5 US measures of both parotid and submandibular salivary glands were scored (0-48 scale). Diagnosis of primary SS was established following the American-European Consensus Group criteria of 2002. The patients' total scintigraphic score (0-12 scale) was determined and the histopathological changes of minor salivary glands graded. Area under the receiver-operating characteristic (ROC) curve was employed to evaluate the diagnostic value of the US scoring system. RESULTS: Primary SS was diagnosed in 107 (79.2%) patients and the remaining 28 subjects (20.8%) constituted the control group. US changes of salivary glands were established in 98/107 patients with SS and in 14/28 controls. Mean US score was 26 in SS patients and 6 in controls. Through ROC curves, US arose as the best performer (0.95 +/- 0.01), followed by scintigraphy (0.86 +/- 0.31). Setting the cutoff score for US at 19 resulted in the best ratio of specificity (90.8%) to sensitivity (87.1%), while setting the cutoff scintigraphic score at 6 resulted in specificity of 86.1% and sensitivity of 67.1%. Among 70 patients with US score >or= 19, a scintigraphic score > 6 was recorded in 54/70 (77.1%) and positive biopsy findings in 62/70 (88.5%) patients. CONCLUSION: We show high diagnostic accuracy of a novel US scoring system of salivary glands (0-48) in patients with primary SS comparable to invasive methods, i.e., scintigraphy and salivary gland biopsy.