Serological tests for syphilis in pregnancy False and missed positive reactions

Abstract

Over a 3-year period, 1969 to 1971, five laboratories in Glasgow carried out serological screening tests for syphilis on the sera from 64,404 pregnant women. 285 tests (442-5 per 100,000) were reported reactive, of which 39 (13-7 per cent.) were confirmed as specific by means of the FTA-ABS and/or TPI test, a rate of 60-6 per 100,000. Three laboratories used a 'battery' of tests, VDRL, RPCF, and either a standard or cardiolipin WR. During 1969, one of these laboratories carried out a Kahn test in addition. Of 37,452 sera tested by these laboratories, 112 (299 per 100,000) were reactive, of which 25 (22 3 per cent.) were confirmed as due to syphilis, a rate of 66-7 per 100,000. The two other laboratories carried out a flocculation test alone; during 1969 a Kahn test, and thereafter the VDRL test. Of 26,952 sera tested, 173 (641-8 per 100,000) were reactive, fourteen (8-1 per cent.) being confirmed as due to syphilis (51-9 per 100,000).