To the Editor.—
The clinical syndrome infectious mononucleosis, known to be caused by Epstein-Barr virus (EBV) infection, classically is described as a generalized malaise with fatigue, pharyngitis, and enlarged lymph nodes; however, depression also commonly accompanies these symptoms. In some cases the depression and constitutional symptoms may last for several months, and even years, after acute physical symptoms subside.1 Recently, within psychiatric support organizations, there has been some publicity about the possible presence of this chronic syndrome in patients with psychiatric disorders,2 and commercial clinical laboratories have noted this finding in brochures circulated to psychiatrists (eg, Specialty Laboratories Inc, Los Angeles). These brochures imply that some cases of depression may be due to unrecognized EBV infection and suggest a battery of immunoglobulin determinations as an indicator of possible underlying virus infection for patients with depression.We examined a population of patients undergoing treatment for a major affective disorder