Major Depressive Disorder Following Dermatomyositis: A Case Linking Depression with Inflammation.

Major depressive disorder (MDD) is one of the most common psychiatric disorders. Recent studies have shown a strong association between MDD and peripheral inflammation, shown by a higher incidence of depression in patients with inflammatory diseases including rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis and systemic lupus erythematosus. Dermatomyositis (DM), an idiopathic inflammatory connective tissue disease that is associated with inflammation, predominantly affects the skin and skeletal muscle. The association between DM and MDD in the context of inflammation has seldom been reported. Here we report a 30- year- old Caucasian female with symptoms of depression dating back to 2 years. These symptoms started after cutaneous manifestations of DM. In the past two years, her DM symptoms have worsened that paralleled an increase of depressive symptoms. Also, during the course of the patient's DM, we tracked elevated inflammatory markers including creatine kinase and aldolase, whereas C-reactive protein, C3, and C4 were in a high normal range which correlated with worsening of depression. Hence, a temporal relationship between the onset of MDD and DM symptoms suggests that inflammation may be a common mechanism linking these two conditions.