Assessment of major salivary gland size in primary Sjögren's syndrome: Comparison between clinical examination and ultrasonography.

OBJECTIVE: Parotidomegaly is a criterion of the EULAR Primary Sjögren Syndrome Disease Activity Index (ESSDAI). The cut-off value was set at 3 cm in length for the parotid gland, 2 cm for the submandibular glands. However, clinical appreciation of salivary glands size remains hazardous. The objective is to evaluate inter-observer reproducibility of parotid gland measurement by palpation, and to secondary evaluate its reliability compared to US assessment. METHODS: Outpatients with primary Sjögren Syndrome (pSS) or with a diagnostic suspicion, in a single reference centre, were included. They underwent clinical examination by two independent investigators (VDP and DC), evaluating: parotid gland swelling, parotid gland size (direct measurement with a decameter under the mandibular angle), and pain. Cohen's kappa coefficient was calculated to determine inter-observer concordance for parotid gland swelling, and intraclass correlation coefficient to determine inter-observer agreement of gland size measurement. RESULTS: Thirty-four patients (33 women, 1 man) were included. Clinical data were complete for 33 patients. Inter-observer concordance Kappa coefficient was 0.90 [0.76-1.00] for detection of parotidomegaly over 66 parotid glands. It was of 0.60 [0.42-0.73] for gland length measurement. For one observer, the median cut-off for defining parotidomegaly was 4.15 cm; for the second observer, it was of 4.92 cm. For submandibular glands palpation, no correlation was found between investigators. A significant association between clinical parotidomegaly and a larger echographic surface was found. CONCLUSION: Clinical measurement of parotidomegaly was concordant between two observers on a binary mode (presence/absence). However, concordance on direct measurement was weak. US could be a complementary examination.

The Differential Diagnosis of Dry Eyes, Dry Mouth, and Parotidomegaly: A Comprehensive Review.

Primary Sjögren's syndrome (pSS) is a frequent autoimmune systemic disease, clinically characterized by eyes and mouth dryness in all patients, salivary gland swelling or extraglandular systemic manifestations in half of the patients, and development of lymphoma in 5 to 10 % of the patients. However, patients presenting with sicca symptoms or salivary gland swelling may have a variety of conditions that may require very different investigations, treatments, or follow-up. Eye and/or mouth dryness is a frequent complaint in clinical setting, and its frequency increases with age. When evaluating a patient with suspected pSS, the first step is to rule out its differential diagnoses, before looking for positive arguments for the disease. Knowledge of normal and abnormal lachrymal and salivary gland physiology allows the clinician to prescribe the most adapted procedures for evaluating their function and structure. New tests have been developed in recent years for evaluating these patients, notably new ocular surface staining scores or salivary gland ultrasonography. We describe the different diagnoses performed in our monocentric cohort of 240 patients with suspected pSS. The most frequent diagnoses are pSS, other systemic autoimmune diseases, idiopathic sicca syndrome and drug-induced sicca syndrome. However, other diseases are important to rule out due to their specific management, such as sarcoidosis, granulomatosis with polyangeitis, IgG4-related disease, chronic hepatitis C virus or human immunodeficiency virus infections, graft-versus-host disease, and head and neck radiation therapy. At the light of these data, we propose a core of minimal investigations to be performed when evaluating a patient with suspected pSS.