THE GENESIS OF NEUROSYPHILIS

If abnormalities in the cerebrospinal fluid may be accepted as criteria of early central nervous system invasion in syphilis, the comparatively recent studies carried out by many observers¹ show that such an invasion takes place in from 20 to 35 per cent, of all patients at the time of the first period of generalization of the disease. Earlier clinical surveys of large numbers of syphilitics (notably that of Mattauschek and Pilcz²) demonstrated that approximately the same, or perhaps a somewhat smaller, percentage of untreated or badly treated patients will develop clinical neurosyphilis. These facts have led to the assumption that neurosyphilis of whatever type practically always originates during the first few months of the infection.

The reasons that every case of syphilis is not thus involved probably are to be found, on the one hand, in the protective mechanism against invasion of the nervous system set up by