Organic syndromes diagnosed as conversion disorder: identification and frequency in a study of 85 patients

Background: The percentage of patients initially diagnosed with a conversio n disorder and later identified as having an organic disorder has been decr easing in recent studies. Method: Consecutive patients with a diagnosis of conversion disorder were referred for psychiatric diagnosis and treatment. Research questions were: (1) What incidence of neurological disorder is rev ealed by neurological reassessment and by which diagnostic technique is the final diagnosis established?, (2) What differences can be observed between true-positive and the false-positive results? Results: Ten (11.8%) of the 85 patients examined appeared to suffer from a neurological disorder. In th is sample, variables discriminating between the true positives and false po sitives were: (1) prior suspicion of neurological disorder; (2) older age a t referral; (3) older age at onset of symptoms; (4) longer duration of symp toms; and (5) use of medication. Three variables contributed significantly to the prediction of organic disorder: prior suspicion of neurological diso rder; age at onset of symptoms; and duration of symptoms. Conclusions: Alth ough our results are in line with those of other recent studies, the percen tage of false positives was still high. The data further emphasize the dang ers of making a diagnosis of conversion disorder in the absence of positive evidence. It is important to continue to provide follow up for patients wi th a diagnosis of conversion disorder. Unfortunately, unreliable psychiatri c indications, like certain behavioral characteristics, are still used in t he diagnostic process; The results show that a general neurological examina tion is still a valuable diagnostic instrument in addition to modem diagnos tic techniques. (C) 2000 Elsevier Science Inc. All rights reserved.