Using ultrasonography to diagnose Sjögren's syndrome

Salivary gland ultrasonography: a highly specific tool for the early diagnosis of primary Sjögren's syndrome

Introduction

Recently, a great interest has arisen for salivary gland ultrasonography (SGUS) as a valuable tool for the assessment of major salivary gland involvement in primary Sjögren’s syndrome (pSS. The aims of this study were to test the accuracy of SGUS for the early detection of pSSand to compare the diagnostic performance of SGUS with minor salivary gland biopsy (MSGB) and unstimulated salivary flow (USFR) in this context.

Method

Patients with suspected pSS and symptoms duration of ≤5 years were consecutively enrolled in this study. The diagnosis of pSS was made according to the AECG criteria. SGUS was performed by two radiologists blinded to the diagnosis and a previously reported ultrasound scoring system (De Vita et al. 1992, cut-off ≥ 1) was used to grade the echostructure alterations of the salivary glands. Statistical analysis was performed using SPSS v16.

Results

This study included 50 pSS patients and 57 controls with no-SS sicca symptoms. The mean(SD) age of the pSS group was lower than non-SS group (47(13) vs 53(12)yrs, p = 0.006). No further differences between the two groups were observed. Patients with pSS showed a significantly higher SGUS score in comparison with controls (mean(SD) = 2.1(1.8) vs 0.0(0.4), p = 0.000). The SGUS cut-off ≥ 1 showed a sensitivity (SE) of 66 %, a specificity (SP) of 98 %, a positive predictive value (PPV) of 97 % and a negative predictive value (NPV) of 73 % for pSS diagnosis. The SGUS score correlated also with patients’ MSGB/FS and USFR.

Conclusions

This study confirmed the good performance of SGUS for the early non-invasive diagnosis of pSS. Further research in larger international cohort of patients is mandatory in order to assess the role of SGUS in the diagnostic algorithm of pSS.

Sonographic diagnostic criteria for screening Sjögren’s syndrome

OBJECTIVE

The objective of this study is to establish readily applied sonographic diagnostic criteria for Sjögren's syndrome.

STUDY DESIGN

Sonographic images of 79 cases of previously suspected Sjögren's syndrome (including 43 actual cases) were analyzed retrospectively for the following characteristic features: (1) multiple hypoechoic areas, (2) multiple hyperechoic lines or spots, (3) multiple hypoechoic areas surrounded with hyperechoic lines or spots, and (4) obscuration of the gland configuration. Logistic regression analysis was used to extract valuable sonographic findings. Sonographic images of 80 prospective patients (of whom 48 proved to have Sjögren's syndrome) were scored prospectively using selected features to verify the usefulness of the established criteria.

RESULTS

Three sonographic findings in parotid and submandibular glands were selected by logistic regression analysis and retrospective and prospective patients compared. Experienced observers could differentiate positive cases of Sjögren's syndrome from negative controls to a highly significant degree. Findings correlated very well with sialographic grading.

CONCLUSION

Sonography can be substituted for sialography when applying the selected criteria in screening for Sjögren's syndrome.

Ultrasonographic changes of major salivary glands in primary Sjögren's syndrome. Diagnostic value of a novel scoring system

OBJECTIVES

To reveal typical ultrasonographic (US) changes in major salivary glands associated with Sjogren's syndrome (SS) and to determine the diagnostic value of a novel US scoring system.

METHODS

In 218 consecutive patients with suspected SS, US of both parotid and submandibular salivary glands was performed besides the regular diagnostic procedure following the American-European Consensus Group criteria of 2002. Five US parameters were assessed: echogenicity, inhomogeneity, number of hypoechogenic areas, the hyperechogenic reflections and clearness of the borders of the salivary gland. The grades of these five parameters for all four salivary glands were summed. The final US score ranged from 0 to 48.

RESULTS

SS was established in 68 patients. The remaining 150 subjects, in whom SS was not confirmed, constituted our control group. All five US parameters were significantly associated with SS. The patients with SS had significantly higher US scores than those not diagnosed with SS (P<0.01). Setting the cut-off US score at 17 resulted in the best ratio of specificity (98.7%) to sensitivity (58.8%).

CONCLUSIONS

Well-defined US changes in the major salivary glands summarized in our novel scoring system were typical of SS patients. Advanced structural changes found on US imaging almost invariably represent SS salivary gland involvement.

Multiple sialolithiasis in the parotid gland with Sjögren's syndrome and its sonographic findings--report of 3 cases

We present 3 cases of Sjögren's syndrome in which multiple sialolithiasis were observed in the parenchyma of the parotid gland. The sonographic examinations showed microliths that were observed as hyperechoic spots. Some of the microliths were accompanied with comet sign, however most of them showed no particular posterior echoes. None of them showed acoustic shadows, which are normally observed in cases with sialolithiasis. We were able to prove that some of the hyperechoic spots observed sonographically in patients with severe Sjögren's syndrome were microliths. Although these multiple microliths are rarely detected, they may exist potentially in higher frequency in patients with severe Sjögren's syndrome.