High prevalence of subclinical Sjögren's syndrome features in patients with autoimmune thyroid disease
Coll, J.; Anglada, J.; Tomas, S.; Reth, P.; Goday, A.; Millan, M.; Pujol-Borrell, R.; Corominas, J.
Journal of Rheumatology 24(9): 1719-1724
1997
ISSN/ISBN: 0315-162X PMID: 9292794 Document Number: 475334
Objective. To determine the prevalence of keratoconjunctivitis sicca and xerostomia related to Sjogren's syndrome (SS) in asymptomatic patients with diagnosed autoimmune thyroid diseases (AITD); and to investigate whether the immunopathologies of sialoadenitis observed in AITD associated SS and primary SS are similar. Methods. One hundred seventy-six patients diagnosed with AITD (88 with Graves' disease, 40 Hashimoto's thyroiditis, 48 primary myxedema) were tested for keratoconjunctivitis sicca (Schirmer's test and rose bengal staining) and for xerostomia (salivary scintigraphy and labial salivary gland biopsy). Immunohistopathological studies were performed on cryostat sections of buccal mucosa biopsies using antibodies to CD3, CD4, CD8, CD20, CD14, CD25, LFA-1, ICAM-3, HLA class II, tumor necrosis factor-alpha, interleukin 1, and interferon-gamma. Results. Nineteen of 52 (37%) patients with AITD fulfilled the criteria for xerostomia and 39/170 (23%) for keratoconjunctivitis sicca. Features of SS were diagnosed in 43 of 176 (24%) patients with AITD, with similar prevalence in Graves' (20%), Hashimoto's thyroiditis (27%), and primary myxedema (29%). In AITD associated SS, infiltrating lymphocytes were mainly CD3+ T lymphocytes, with a CD4/CD8 ratio of 2:1. In most patients infiltrating lymphocytes expressed activation markers, HLA class II molecules, and interleukin 2 receptor (CD25). In some patients HLA class II was inappropriately expressed in the epithelial gland cells. Conclusion. The finding that a third of patients with AITD have SS features confirms that AITD and SS are mutually associated. Together with the similarity of immunopathology of sialoadenitis in AITD associated SS in primary SS, this supports the theory that SS and AITD are 2 autoimmune diseases closely related pathogenetically.