Tongue Tremor in Systemic Lupus Erythematosus

A 32-year-old woman presented to our rheumatology clinic with a 1-month history of gradually worsening dysarthria attributable to tongue tremor (Video S1), fever, malaise, malar rash (Fig), chest pain, polyarthralgia, and finger tremor (Video S2). Laboratory findings indicated pancytopenia, with lymphopenia and hypocomplementemia. The patient was positive for anti-nuclear, anti-dsDNA, and anti-Sm antibodies, but negative for anti-cardiolipin antibody, anti-cardiolipin/β2 glycoprotein I antibody, and lupus anticoagulant. Urinalysis revealed hematuria and proteinuria. A cerebrospinal fluid test showed elevated interleukin-6 (7.34ng/ml) and interleukin-8 (84ng/ml). Single photon emission computed tomography (SPECT) revealed reduced perfusion in the prefrontal and occipital lobes. In addition, electroencephalography revealed diffuse slow-wave activity. Magnetic resonance imaging of the brain and spine was normal. The patient was thus diagnosed with neuropsychiatric systemic lupus erythematosus (NPSLE) and lupus nephritis. The prevalence of NPSLE varies from 12 to 90% in patients with SLE. The common manifestations of NSPLE include headache, mood disorders, anxiety, and cognitive dysfunction. The prevalence of movement disorder is reported to be 0.9%, and tremor is also a rare manifestation of NPSLE. Diagnosis and management of NPSLE remain challenging. A multifaceted approach is required to diagnose NPSLE based on laboratory tests, such as antibodies and cerebrospinal fluid, electroencephalography, and imaging studies. These findings also help to exclude mimickers, including central nervous system infections, malignancy, and metabolic disorders. Owing to its heterogeneity, rarity, and the absence of large clinical trials, an effective treatment for NSPLE has not yet been established. Patients with NPSLE are usually treated with a high dose of glucocorticoids and occasionally require cyclophosphamide or rituximab. This patient was treated with methylprednisolone (1,000mg) for 3 days, followed by prednisolone (50mg). The tremor responded well to the pulsed steroid therapy and resolved completely in 2 weeks, as did the fever, malar rash, polyarthralgia, finger tremor, pancytopenia, and hypocomplementemia. Subsequently, the prednisolone dose was tapered to 7mg/day in 6 months, and tacrolimus, mycophenolate mofetil, and hydroxychloroquine were added as maintenance therapy. The patient has been well controlled, without any relapses. FIGURE: Tongue tremor with malar rash. [Color figure can be viewed at www.annalsofneurology.org]