Bilateral facial paralysis as a rare neurological manifestation of primary Sjögren's syndrome: case-based review.

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disorder associated with a variety of systemic presentations. Varied neurological dysfunctions of newly diagnosed adult patients with pSS have been observed in recent years. We aimed to describe a rare case of acute bilateral facial paralysis diagnosed with pSS for the first time and review the previous studies including similar cases. A 69-year-old female, who had experienced ocular and oral dryness for more than 10 years, presented with bilateral facial palsy. Her laboratory test results showed positive anti-Ro (SSA) and anti-Ro-52 antibodies. Ophthalmic examination and test of saliva secretion verified xerophthalmia and xerostomia, respectively. Other possibilities of Lyme disease, Möbius syndrome, tumor, bilateral temporal bone fracture, Guillain-Barré syndrome, central nervous system lymphoma and HIV infection were ruled out. A diagnosis of pSS associated with bilateral facial paralysis was made. The literature review revealed one article describing a similar patient. Our case was the only one suffering from acute bilateral facial palsy without other nerve involvement. The presence of such patients reveals that pSS is an underlying cause of acute bilateral facial paralysis.