Staging Late Latent Syphilis: An Evaluation of Disease Intervention Specialist Case Assignment Outcomes

Background:  In Virginia, late latent (LL) syphilis cases do not routinely receive Disease Intervention Specialist (DIS) interviews. However, LL syphilis diagnoses rose 62% from 2013 (n=193) to 2014 (n=313). The percent of all syphilis cases staged LL increased from 22% to 36%. The total number of syphilis cases diagnosed remained stable during this time period.

Methods:  Demographics and geographic areas experiencing increases in LL syphilis in 2014 were identified using Virginia’s STD surveillance database. A subset of LL syphilis case investigations meeting high priority criteria (primarily patients under age 35) was identified and evaluated. Field records and other associated documentation, both electronic and paper, were reviewed to assess trends, case assignment consistency, and any "red flags." 

Results:  Of the sampled cases (n=50) pre-identified as high priority for review, 52% had recent high (1:16 or higher) RPR titers. Two patients had recent history of symptoms that may be attributable to early syphilis. From 2013 to 2014, LL syphilis diagnoses increased in nearly every age group, with the largest increases in 15-19 year olds (700%; 1 to 8 cases) and 25-29 year olds (192%; 12 to 35 cases). Diagnoses increased in all five health regions, particularly Southwest (144%; 9 to 22 cases) and Central (104%; 27 to 55 cases); among every race and ethnicity, particularly among black individuals (94%; 86 to 167 cases); and among both males (75%; 116 to 203 cases) and females (43%; 77 to 110 cases).

Conclusions:  The total number of syphilis diagnoses remained stable from 2013 to 2014. The 2014 increase in cases staged LL, and the simultaneous decrease in cases staged early latent, was followed by a dramatic increase (36%) in total early syphilis diagnoses in 2015. A regional approach to DIS coordination is in development, which will enhance paperwork review. This will help to determine whether intervention opportunities are missed in syphilis cases staged LL. Routine analysis of LL syphilis is now performed to monitor trends.