Background The diagnostic process for conditions in which an inflammatory rheumatologic and/or connective tissue disease (CTD) is suspected consists primarily of history taking and physical examination. These two activities give the most important information leading to a differential diagnosis. Additional investigations can be helpful to confirm a tentative diagnosis, rule out other diagnoses or lead to other manifestations in (but also without) relation to the presumptive disease. Before requesting additional investigation(s) one should realize that these investigations should meet with the following conditions: it should give additive information to the information available from history taking and physical examination, it should be discriminative and the outcome should have therapeutic consequences. Participation in studies on clinical or translational scientific issues may also require additional investigations to complete classification and/or inclusion criteria.

Indications of labial salivary gland biopsy are confirmation of a presumptive diagnosis of Sjögren’s syndrome and other conditions causing dryness and/or salivary gland enlargement including sarcoidosis. PrimarySjögren’s syndrome (pSS) is a slowly progressive autoimmune disorder, affecting mainly the exocrine glands, resulting in mucosal dryness of eyes, mouth, and vagina. PSS is a clinical diagnosis which may be confirmed by salivary gland biopsy, which is to be performed easily by clinicians including rheumatologists. The procedure is widely considered and used as the single most specific test for confirming a diagnosis of pSS.

Main histopathological findings in salivary glands in pSS are focal sialo-adenitis with a focus-score ≥1 (focus: aggregate of > 50 lymphocytes and histiocytes per 4 mm²) and an increase of IgG and IgM containing plasma cells.

Technical procedures will be elucidated.

Limitations including histological changes in salivary gland tissue being not 100% specific, focal sialo-adenitis not being pathognomic for pSS, will be discussed.

Complications including persistent hypoesthesia of the lower lip region, when a nerve, in spite of the procedure of which all details can be followed by sight, is damaged, will be shared.

Key messages to share How to use labial salivary gland biopsy in diagnosis and classification of pSS.

Labial salivary gland biopsy is to be performed easily by a rheumatologist.

Disclosure of Interest None Declared