Folie à Deux in the aged: variations in psychopathology.

The etiology of Folie à Deux remains a controversial topic; the relationship between the psychopathology exhibited by the dominant partner and that shown by the submissive one being particularly unclear. Modern etiological theories attempt to reduce the phenomena of Folie à Deux to a procrustean mould, emphasizing in particular the contribution of schizophrenic pathology to the development of the condition. A case is described which raises doubts about the general applicability of this approach.