Objective: to analyze the nosological spectrum, demographic, clinical and laboratory characteristics of diseases with a significant enlargementof major salivary (SG) / lacrimal glands, and/or accessory organs of the eye and paranasal sinuses lesions in rheumatological practice.Patients and methods. This work includes 73 patients who underwent a complex clinical and laboratory, imaging, pathomorphological and histomolecular examination, which was necessary to establish a nosological diagnosis. In all cases, the diagnosis was confirmed pathomorphologically.Results and discussion. Sjogren's syndrome (SjS) was diagnosed in 30 (41%) patients (14 of them developed lymphoproliferative disorder, LPD, as a complication), granulomatosis with polyangiitis (GPA) – in 12 (16.4%), IgG4-related disease (IgG4-RD) – in 10 (13.7%), sarcoidosis – in 6 (8.2%), non Langerhans cell histiocytosis – in 2 (2.7%), AL-amyloidosis – in 1 (1.4%), Warthin's tumor – in 1 (1.4%), chronic atrophic rhinitis – in 1 (1.4%), infectious lesions – in 3 (4.1%) (HIV-associated – in 2, dirofilariasis – in 1), idiopathic inflammatory pseudotumor – in 6 (8.2%). In 1 (1.4%) patient, the diagnosis could not be established.A massive increase of major SG was observed in 46 patients, more often (in 28 cases) with SjS with LPD or without it, with IgG4-RD (in 7) and sarcoidosis (in 6). Orbital lesions were observed in 18 patients: in 7 with IgG4-RD, in 5 with idiopathic inflammatory pseudotumor, in 2 with sarcoidosis, in 2 with GPA, and in 1 each with non Langerhans cell histiocytosis and dirofilariasis. Nasal lesions in the form of chronic rhinosinusitis with or without nasal septum perforation, were found in 18 patients, 12 of whom suffered GPA and 6 – IgG4-RD.Two algorithms, that can facilitate the choice of additional studies and the direction of diagnostic search have been proposed for practicing rheumatologists.Conclusion. Taking into account the possible similarity of clinical manifestations of the diseases with the formation of mass-like tissue, the differential diagnosis should be based on pathomorphological study.