To assess the diagnostic value of salivary gland ultrasonography (SGUS) for IgG4-related sialadenitis.
Ultrasonography examination of major salivary glands was conducted for 48 IgG4-related sialadenitis patients and 50 Sjögren's syndrome patients, whose ages and disease duration were matched. The imaging features were graded using two different scoring systems (0-16 and 0-48, respectively) obtained from the grades of bilateral parotid and submandibular glands. The scores were used to further evaluate the features of salivary gland ultrasonography in IgG4-related sialadenitis and to compare them with Sjögren's syndrome patients. The association of SGUS scores of IgG4-related sialadenitis group with serological tests was analyzed.
The mean age of IgG4-related sialadenitis group and Sjögren's syndrome group was 49.23 years and 50.44 years, respectively. The serum IgG4 level of the patients in the IgG4-related sialadenitis group was increased, with an average (9.60±6.43) g/L. And the serum IgE level was at a median of 251.5 (123.4-543.6) IU/mL. In the 0-16 system, the scores of submandibular glands of the patients in IgG4-related sialadenitis and Sjögren's syndrome were 6.0 (6.0-8.0) and 4.0 (2.0-8.0), and the scores of the total four glands were 10.0 (8.0-14.0) and 8.0 (4.0-12.0) respectively. In the 0-48 system, the scores of submandibular glands with IgG4-related sialadenitis and Sjögren's syndrome were 18.0 (14.5-20.0) and 11.0 (7.0-14.0), and the scores of the total four glands were 26.0 (18.5-34.0) and 21.5 (15.0-26.3) respectively. It suggested that in the 0-16 system and the 0-48 system, scores of submandibular glands and the total of four glands of IgG4-related sialadenitis were higher than those of Sjögren's syndrome. Meanwhile, the association analysis of 0-48 system showed a positive correlation of SGUS scores with serum IgG4, which also showed a positive correlation of SGUS scores with serum IgE in 0-16 system.
Semi-quantitative ultrasonography scoring systems can evaluate and quantify the lesions of salivary glands, which can be helpful in the diagnosis and differential diagnosis of IgG4-related sialadenitis combined with the clinical manifestations, serological indicators and/or histopathological manifestations. Ultrasonography can also assess the activity of IgG4-related sialadenitis preliminarily.