CD4 and neurosyphilis: In an alternative analysis, considering only CSF positive VDRL titers as confirmed neurosyphilis criteria, neurologic symptoms (OR = 5.74, 95 % CI 1.72‒19.09, p = 0.004), VDRL serological titers ≥ 1:32 (OR = 8.9, 95 % CI 1.10–73.4, p = 0.043) and CD4 count ≤ 350 cells/mm3 (OR = 4.4, 95 % CI 1.5‒13.6, p < 0.001) were independent risk factors, while HIV viral load ≤ 400 copies/mm3 (OR = 0.25, 95 % CI 0.8‒0.76, p = 0.015) was a protective factor.