**Abstract**

Sjögren's syndrome (SS) affects numerous different areas, and many specialists may be involved in the diagnosis and treatment of SS. Otolaryngological and dental manifestations, neurological impairment, and hearing loss may be the initial symptoms of SS. This chapter describes the most common otolaryngological and oral manifestations of SS, its pathomechanism and possible etiology. Dryness accompanying SS is associated with many clinical implications. The rate of dry mouth in SS ranged from 41% at initial diagnosis to 84% 10 years after diagnosis. An unstimulated salivary flow rate of 0.1 ml/min in sialometry gives a score of 1 to the weighted sum of 5 items according to the current EULAR/ACR criteria. The presence of mononuclear cell aggregates around the ducts and acini of salivary glands results in functional and structural alterations at the level of these glands and impairs their secretory function. The most common oral signs and symptoms are dental caries, tooth decay, fungal infections, traumatic oral lesions, dysphagia, dysgeusia, and inflammation of the salivary glands. Saliva in SS is characterized by the increased concentration of lactoferrin, potassium and cystatin C and the decreased concentration of amylase, carbonic anhydrase, mucins, histatines, IgA, statherins, proline-rich proteins, and the loss of salivary buffer properties. The lack of these physiological defense mechanisms increases the risk of opportunistic infections, mainly fungal infections by *Candida albicans*. Candidiasis accompanies angular cheilitis, simple cheilitis, and exfoliative cheilitis. The salivary glands of SS patients are characterized by chronic inflammation with the presence of lymphocytic infiltrates located around the striated ducts. These periductal foci may lead to the development of organized ectopic lymphoid structures resembling secondary lymphoid organs with segregated T- and B-cell areas, and high endothelial venules. These structures become an active center of immune response. The presence of foci in labial salivary glands is a hallmark of SS, and their histopathologic analysis is an important item in the diagnosis and classification. A biopsy can be taken from either the labial or the parotid salivary gland, but currently according to the diagnostic criteria, only labial salivary gland biopsy (LSGB) is recommended to confirm the diagnosis of SS. The authors present their own experience and recommendations in taking labial salivary gland biopsy, the main surgical approaches, and the main limitations for this diagnostic method and describe the possibilities and principles of histopathological examination in SS. The authors present the main ultrasonic signs of SS major salivary glands and perspectives of the usage of salivary gland ultrasonic examination in the diagnosis and monitoring of SS. The presented chapter also includes the most common laryngological manifestations associated with SS: nose dryness, crusting,

or atrophy of the nasal mucosa, dryness of the throat, dysphagia, hoarseness, otalgia and tinnitus, gastro-esophageal reflux, and chronic cough. Patients with SS tend to have a higher prevalence of sensorineural hearing impairment compared with the general population. Idiopathic hearing loss may represent the initial manifestation of SS. Furthermore, authors present and discuss the main neurological symptoms of SS. Neurological manifestations are reported in about 20% of patients with SS. In patients with SS, neurological manifestations may occur, such as peripheral neuropathy and other forms of neuropathies, including sensory ataxia, painful sensory neuropathy without sensory ataxia, multiple mononeuropathy, multiple cranial neuropathy, autonomic neuropathy, radiculoneuropathy and intra- and extraoral paresthesias, facial hypaesthesia, and trigeminal nerve neuropathy.

**Keywords:** Sjögren's syndrome, hearing loss, cranial nerve neuropathy, xerostomia
