Epidemiology of infectious syphilis at a tertiary hospital.

In 19 of 20 patients in whom the correct diagnosis of primary or secondary syphilis was not obvious initially, a positive routine admission VDRL test result was the first indication of the correct diagnosis. A retrospective study during a one-month period to correlate hospital admissions by clinical service with required routine admission serologic tests for syphilis disclosed an overall compliance rate of only 37.1% (range, 94.6% to 8.0%). Of the 38 patients who did have a positive admission VDRL test result, 55.3% were falsely positive. The false-positive rate was slightly higher for weakly reactive titers than it was for higher titers. The routine serologic testing program uncovered 129 and 116 new cases of syphilis during 1976 and 1977, respectively. The decision to continue the routine admission VDRL screening program was made because the consequences of an incorrect diagnosis could be very great for an individual patient.