Evaluation of Congenital Syphilis: Use of an Algorithm in a Reverse Sequence Testing System

BACKGROUND: From 2012 to 2015, the CDC reported an increase in congenital syphilis (CS) cases. Reverse sequence (RS) testing is reported as a high throughput and cost effective method for syphilis screening. RS testing starts with a treponemal specific antibody test (e.g. chemiluminescent immunoassay [CIA]), then reflexive testing with a non-treponemal antibody test (rapid plasma reagin [RPR]) when CIA is positive. In cases with discordant results (e.g., CIA positive, RPR negative), a different second treponemal specific antibody test is performed (e.g. fluorescent …