Asymptomatic Cerebrospinal Fluid HIV-1 Viral Blips and Viral Escape During Antiretroviral Therapy: A Longitudinal Study

We examined longitudinal cerebrospinal fluid (CSF) samples (median, 5 samples/patients; interquartile range [IQR], 3-8 samples/patient) in 75 neurologically asymptomatic human immunodeficiency virus (HIV)-infected patients receiving antiretroviral therapy. Twenty-seven patients (36%) had >= 1 CSF HIV RNA load of > 20 copies/mL (23% had >= 1 load of > 50copies/mL), with a median HIV RNA load of 50 copies/mL (IQR, 3277 copies/mL). In plasma, 42 subjects (52%) and 22 subjects (29%) had an HIV RNA load of >20 and >50 copies/mL, respectively. Two subjects had an increasing virus load in consecutive CSF samples, representing possible CSF escape. Of 418 samples, 9% had a CSF HIV RNA load of >20 copies/mL (5% had a load of > 50 copies/mL) and 19% had a plasma HIV RNA load of > 20 copies/mL (8% had a load of >50 copies/mL). A CSF-associated virus load of >20 copies/mL was associated with higher CSF level of neopterin. In conclusion, CSF escape was rare, and increased CSF HIV RNA loads usually represented CSF virus load blips.