HIV, Syphilis, and When to LP

Syphilis is a significantly prevalent STD in North Carolina, particularly in the setting of co-infection with HIV. Screening for syphilis is reviewed in the Syphilis Screening section of the blog. But, a common question that must be addressed in this circumstance is:

When is it necessary to perform an LP in to rule out Neurosyphilis in the HIV-positive patient?

The answer has many answers, but the commonly accepted answer is as follows: "All neurologically asymptomatic HIV-infected patients whose serum RPR titer is greater than or equal to 1:32 should undergo lumbar puncture regardless of syphilis stage." And, of course, any symptomatic HIV-patient with a history of syphilis should undergo LP to rule out Neurosyphilis.

This recommendation is taken from two main studies:

• Marra, et al. J Infect Dis 2004; 189: 369 - 376.
• Libois, et al. Sex Transm Dis 2006. HIV and syphilis: When to perform a lumbar puncture.

Yvonne Carter, MD