Atypical Trigeminal Neuralgia: A Rare Neurological Manifestation of Systemic Lupus Erythematosus.

BACKGROUND Systemic lupus erythematosus (SLE) is a multisystem autoimmune disorder of unknown etiology which can present at any age with symptoms of mucocutaneous, musculoskeletal, renal, central nervous system, and nonspecific clinical pictures making the disease a "master of mimicry". CASE REPORT A 53-year-old female, who was recently diagnosed with SLE, presented with right-sided sharp and electric shock-like facial pain starting at the side of her right nostril and traveling down the naso-labial fold and then back to the angle of the jaw, mostly in the region of V2-V3 distribution with no radiation beyond trigeminal distribution. Her pain had been going for the last 2 years and was regarded as "pretrigeminal neuralgia"; however, it progressed in frequency over the last 2 weeks, with no clear identifying triggering factors. Her laboratory test results showed positive anti-nuclear antibodies (ANA) with raised titer, anti-double-stranded DNA, anti-ribonucleoprotein, anti-Sjögren's syndrome-related antigen A, anti-Sjögren's syndrome-related antigen B, and anti-smooth muscle antibodies. Other possibilities of migraine, postherpetic neuralgia, Bell's palsy, and brain tumor were ruled out. A diagnosis of SLE with trigeminal neuralgia (TN) was made and carbamazepine 100 mg 2 times a day was prescribed. CONCLUSIONS TN is seldom mentioned as a neurological manifestation of SLE; hence, we recommend further studies to investigate the SLE-mediated injury to trigeminal fibers to make a timely diagnosis of TN and to prevent progressive autoimmune process-related vasculitic and demyelinating changes.