Background:
In response to the outbreak of Primary and Secondary (P&S) syphilis among MSM in Chicago, Chicago Department of Public Health (CDPH) enhanced Neurosyphilis (NS) reporting system.

Objective:
To describe changes in the epidemiology of NS in Chicago, IL.

Method:
Surveillance and interview data for cases of NS were analyzed using SAS version 9(1). Diagnosis of NS was based on the CDC and CDPH surveillance case definitions. Surveillance of NS was enhanced in 2006.

Result:
Between 2004 and 2006, a total of 59 cases of NS (confirmed, probable and suspect cases) were reported to the CDPH. Of the 50 cases in males, 25(50%) were in MSM, 5(10%) in heterosexual men and 20(40%) in men with unknown sexual orientation. Between 2004 -2006, NS cases increased by 71% (from 14 to 24). In total 24 patients (1 female, 11 MSM, 4 heterosexual males and 8 male-unk) were diagnosed with NS in 2006. Approximately 63% (15/24) were confirmed cases, 29.5%( 7/24) were probable and 8%(2/24) were suspect NS cases. The median age of MSM was 44 years (range 20-55). MSM with NS were more likely to be white (64%), while 27% were African Americans and 9% were Hispanics. The majority, 81% of MSM were co-infected with HIV and had a median CD4 cell count of 332. At the time of NS diagnosis among MSM 4(36%) patients had secondary syphilis and 1(9%) patient was diagnosed with early latent syphilis. Two patients reported previous history of syphilis and had documented adequate previous penicillin treatment.

Conclusion:
The majority of NS cases in Chicago occurred among MSM co-infected with HIV infection.

Implications:
Clinicians should be alert to signs and symptoms of NS especially among MSM. MSM should be counseled about various sings of NS and the risk for illness and permanent disability.