Abstract
Reduced erythrocyte magnesium (Mg) levels have been reported in fibromyalgia syndrome (FS), chronic fatigue syndrome (CFS), myofascial pain syndrome (MPS) and eosinophilia myalgia syndrome (EMS). These disorders have chronic pain as a common symptom. Chronic pain also affects some patients with systemic lupus erythematosus (SLE). To determine if SLE patients are also prone to hypomagnesemia, red blood cell (RBC) and plasma Mg levels were measured in all SLE patients seen in a general rheumatology practice in a 3-year period. There were 25 such patients with a mean age of 47 years. Thirteen SLE patients had FS and 12 did not have either FS or MPS. The mean RBC Mg level for the SLE patients was 4.60 mg dl - 1, statistically significantly lower than that of the reference controls and 12 osteoarthritis controls. It did not matter whether the SLE patients had FS or MPS. This finding has implications for diagnosis and treatment.