Abstract
Background Sjögren's syndrome is a systemic autoimmune disease characterized by dry mouth and dry eyes. The disease may extend to involve various organs and can cause certain peripheral nervous system complications, the most common of which are polyneuropathy and sensory ganglionopathy. Cranial nerve involvement in Sjögren's syndrome is rare and has been sparsely described in the literature. Methods We describe the clinical case of a 64-year-old female patient who developed facial sensory and motor symptoms one year prior to the confirmed diagnosis of Sjögren's syndrome. Results The cranial nerve lesions most frequently reported in the literature as inflammatory complications of Sjögren's syndrome involve cranial nerve II (optic neuritis) and cranial nerve V. In our case report, the patient presented with a constellation of symptoms characteristic of combined sensory-motor ganglionopathy: atypical trigeminal neuralgia-type sensory disturbance, myokymia of the orbicularis oris and mentalis muscles, and bilateral orbicularis oculi weakness. Positive anti-SSA antibody testing, together with a labial minor salivary gland biopsy showing a focus score of 2, allowed for a definitive diagnosis. Conclusion Although cranial nerve involvement is a rarer complication compared to other forms of peripheral neuropathy in Sjögren's syndrome, it is a serious complication that significantly affects patients' quality of life. Diagnosis requires early recognition of symptoms combined with appropriate paraclinical investigations, among which serologic testing and labial minor salivary gland biopsy are simple, easily performed investigations that provide high diagnostic value for this autoimmune disease.
