[Lithium prevention of depression 100 years ago--an ingenious misconception].

The rediscovery of C. Lange's book "Uber periodische Depressionszustände und ihre Pathogenesis auf dem Boden der harnsauren Diathese", Copenhagen 1886, in a German translation by H. Kurella in 1896, gave rise to appreciate its value, to make its misconception intelligible, and to write down the author's and the translator's course of life. In his booklet Carl Lange gives a specification of depression in a most modern form. It is thrilling to read his report on about 2000 depressed out-patients successfully treated over a 20-year-period - from today's point of view lege artis - with lithium carbonate as a long-term-prophylaxis for recurrent depression. His intricate misconception is based upon his therapeutic orientation of treating gout and "uric acid diathesis", respectively. This conception of depression as "brain gout", part of an inflationary enlarged pathogenesis of numerous internal, neurological, and other diseases, had been set up by Garrod. "Brain gout" was a curiosity in the established psychiatry and disappeared from scientific thinking with a new medical knowledge of gout and rheumatism. With that, of course, the pioneering knowledge of the effectiveness of lithium disappeared too.