Background: Neopterin, a biomarker of macrophage activation, is elevated in the cerebrospinal fluid (CSF) of most HIV-infected individuals and decreases after initiation of antiretroviral therapy (ART). We studied decay characteristics of neopterin in CSF and blood after commencement of ART in HIV-infected subjects and estimated the set-point levels of CSF neopterin after ART-mediated viral suppression.Methods: CSF and blood neopterin were longitudinally measured in 102 neurologically asymptomatic HIV-infected subjects who were treatment-naïve or had been off ART for ≥ 6 months. We used a non-linear model to estimate neopterin decay in response to ART and a stable neopterin set-point attained after prolonged ART. Seven subjects with HIV-associated dementia (HAD) who initiated ART were studied for comparison.Results: Non-HAD patients were followed for a median 84.7 months. Though CSF neopterin concentrations decreased rapidly after ART initiation, it was estimated that set-point levels would be below normal CSF neopterin levels (<5.8 nmol/L) in only 60/102 (59%) of these patients. Pre-ART CSF neopterin was the primary predictor of set-point (P <0.001). HAD subjects had higher baseline median CSF neopterin levels than non-HAD subjects (P <0.0001). Based on the non-HAD model, only 14% of HAD patients were predicted to reach normal levels.Conclusions: After virologically suppressive ART, abnormal CSF neopterin levels persisted in 41% of non-HAD and the majority of HAD patients. ART is not fully effective in ameliorating macrophage activation in CNS as well as blood, especially in subjects with higher pre-ART levels of immune activation. © 2013 Yilmaz et al.; licensee BioMed Central Ltd.

Though depression is known to frequently afflict those with chronic HIV, mood during the early course of HIV is not well characterized. In a prospective study we assessed mood during primary HIV infection [primary HIV infection (PHI), <1 year duration], its association with neuropsychological performance and markers of neurological disease, and its longitudinal course including effects of antiretroviral therapy (ART). The Beck Depression Inventory (BDI) and Profile of Mood States (POMS) subscales were longitudinally administered prior to and after ART in PHI subjects. This evaluation of mood was done concurrently with blood, cerebrospinal fluid (CSF) and neuropsychological [total z and global deficit score (GDS)] evaluation at each visit. Analysis employed Spearman's rho, logistic regression, and linear mixed models. 47.7 % of the 65 men recruited at a median 3.5 months HIV duration met BDI criteria for clinical depression at baseline, classified as 'mild' (n = 11), 'moderate' (n = 11), or 'severe' (n = 9). Drug, alcohol, and depression history did not associate with BDI score. Proportional somatic-performance scores were worse than cognitive-affective scores (p = .0045). Vigor subscore of POMS was reduced compared to norms and correlated with total z (r = 0.33, p = 0.013) and GDS (r = -0.32, p = 0.016). BDI and POMS correlated with one another (r = 0.85, p<.0001), but not with CSF or plasma HIV RNA, WBC, albumin ratio or neopterin. Improvement was not observed in BDI and POMS over 330 total follow-up visits, even after initiation of ART. Depression was prevalent during PHI in our subjects, associated with abnormal somatic-performance and vigor scores. Neither neuropsychological performance nor disease biomarkers correlated with depressed mood. Mood indices did not improve over time in the presence of ART. © Springer Science+Business Media New York 2014.