Ocular myasthenic syndrome and systemic lupus erythematosus

Background: Reports on association of systemic lupus erythematosus (SLE) and myasthenia gravis are sparse. Case report: An 40-year old woman complained of sudden onset of diplopia. A SLE was known for 6 years. Both eyes showed a deficit in upgaze, the right eye showed a deficit in abduction and a slight ptosis. Further ophthalmologic and neurologic status were normal. Magnetic resonance tomographic imaging of the brain and the results of the spinal fluid examination were unremarkable. Sono-graphic imaging and magnetic resonance tomographic imaging studies showed normal extraocular muscles. The edrophonium test (short acting inhibitor of acetylcholinesterase) was positive (elevation of the ptotic lid after injection of edrophonium). Acetylcholine receptor antibodies were elevated to 70 nmol/l (norm: < 0.25 nmol/l). Thoracic computed tomographic scan showed no evidence of a thymoma/thymus hyperplasia or thymus carcinoma. Systemic steroid treatment resolved the complaints within weeks. Conclusions: The patient with SLE had an ocular myasthenic syndrome. The etiology of the association of the two autoimmune diseases is not clear. SLE patients showing fatigue signs or pareses should be examined for myasthenia gravis. Patients with isolated ocular myasthenic syndromes should be examined for a generalized immunological disorder.