Abstract: Objective To assess the effect of early syphilis on CD4 cell count among men who have sex with men (MSM) with human immunodeficiency virus(HIV) infection. Methods Cases of early syphilis in HIV infected patients among MSM were included. Benzathine penicillin was given after the diagnosis of syphilis. CD4 cell counts were measured by flow cytometry before, during, and after three and six months of treatment, and the results were compared. Results Fifty patients were included, and forty-five patients had successful treatment of syphilis. CD4 cell count decreased significantly during infection in patients with early syphilis(P=0.04). There was no significant difference in the levels of CD4 cell during infection and after the 3-month treatment(P>0.05), and CD4 cell count increased significantly during infection and after the 6-month treatment(P=0.02). Conclusion CD4 cell count decreased in the early infection with Treponema pallidum in HIV infected patients, and the successful treatment of syphilis can reverse the trend.

Key words: early syphilis, acquired immune deficiency syndrome, benzathine penicillin, CD4⁺T cells