The prevalence of positive serological tests for syphilis among elderly hospital patients.

Serological tests for syphilis were performed on 659 elderly patients admitted to hospital medical and psychiatric departments. Positive tests were found in 23 patients (3.5% of the sample), 17 women and 6 men. Six were subsequently discovered to have been treated previously for syphilis, and one other had radiological evidence to suggest that she had been treated with bismuth in the pre-penicillin era. Difficulties were encountered in classifying the stage of infection in some patients, particularly those with significant intellectual impairment. Eleven were diagnosed as late latent syphilis, seven as probable late latent syphilis, one as tabes dorsalis, one as possible cardiovascular syphilis, one as possible meningovascular syphilis, and one as late congenital syphilis.