Ulfhammer G, Edén A, Antinori A, et al. - This large multicenter study was conducted with the aim to determine how cerebrospinal fluid (CSF) HIV-RNA differs in different phases of untreated HIV-1 infection and examine the associations of its variations with plasma HIV-RNA and other biomarkers.

• A total of 1.018 treatment naïve adults were included.

• Findings support the existence of variations in CSF HIV-RNA in different stages of HIV disease.

• When compared with plasma, there was lower CSF HIV-RNA in CSF by nearly 1 log₁₀ copies/mL.

• CSF HIV-RNA was noted to be correlated with plasma HIV-RNA, neopterin concentration in CSF and in serum, CSF WBC and albumin ratio.

• However, there was CSF discordance in a substantial minority of individuals, most commonly in patients with HIV-associated dementia (HAD), suggesting increasing CNS compartmentalization paralleling disease progression.