Short communication: focal encephalitis related to viral escape and resistance emergence in cerebrospinal fluid in a patient on lopinavir/ritonavir monotherapy with plasma HIV-1 RNA suppression

Cerebrospinal fluid viral escape in HIV patients on antiretroviral therapy: A systematic review of reported cases

Cerebrospinal fluid (CSF) viral escape rarely occurs when HIV is detected in the CSF, while it is undetectable in the blood plasma or detectable in CSF at levels that exceed those in the blood plasma. We conducted this review to comprehensively synthesise its clinical presentation, diagnosis, management strategies and treatment outcomes. A review registered with PROSPERO (CRD42023475311) searched evidence across PubMed/MEDLINE, Embase, Web of Science, Scopus, and Google Scholar to gather articles (case reports/series) that report on CSF viral escape in people living with HIV (PLHIV) on antiretroviral therapy (ART). The quality of studies was assessed based on the domains of selection, ascertainment, causality, and reporting. A systematic search identified 493 articles and 27 studies that include 21 case reports, and six case series were involved in the review. The studies reported 62 cases of CSF viral escape in PLHIV. The majority were men (66.67%), with a median age of 43 (range: 28-73) years. Approximately, 31 distinct symptoms were documented, mostly being cognitive dysfunction, gait abnormalities, and tremors (12.51%). Diagnosis involved blood and CSF analysis, magnetic resonance imaging, and neuropsychological assessments. Over 36 ART regimens were employed, with a focus on ART intensification; almost one-third of the regimens contained Raltegravir (integrase strand transfer inhibitor). The outcomes showed 64.49% full recovery, 30.16% partial recovery, and 4.76% died. When neuropsychological symptoms manifest in PLHIV, monitoring for CSF viral escape is essential, regardless of plasma viral suppression. Personalised treatment strategies, particularly ART intensification, are strongly advised for optimising treatment outcomes in PLHIV diagnosed with CSF HIV escape.

Studying the Changes in Physical Functioning and Oxidative Stress-Related Molecules in People Living with HIV after Switching from Triple to Dual Therapy

BACKGROUND

Physical activity could increase the production of oxidative stress biomarkers, affecting the metabolism and excretion of antiretroviral drugs and, consequently, the clinical outcome. Nowadays, people living with HIV (PLWH) are mostly switching from triple to dual therapy, but no data are available in terms of physical functioning and oxidative stress. The aim of this study was to evaluate if some antioxidant biomarkers and physical functioning tests could be different according to triple or dual antiretroviral therapy.

METHODS

PLWH were evaluated at baseline (BL), while treated with three drugs, and six months after the switch to dual therapy. Physical functioning was quantified using validated tools. Mitochondrial and cytosol antioxidant molecules were evaluated through liquid chromatography.

RESULTS

Twenty-five patients were analyzed. A statistically significant difference between triple and dual therapy was found for mitochondrial glutathione, but not for physical tests. Evaluating differences between physically active and inactive individuals, the following statistically significant differences were suggested, considering triple therapy (mitochondrial n-formyl-methionine p = 0.022, triglycerides p = 0.023) and double therapy (mitochondrial glycine p = 0.035, cytosol glutamic acid p = 0.007, cytosol s-adenosylmethionine p = 0.021).

CONCLUSIONS

For the first time, this study suggests possible differences in terms of antioxidant molecules and physical functioning in PLWH switching from triple to dual therapy.

The symptomatology of cerebrospinal fluid HIV RNA escape: a large case-series

OBJECTIVE

To characterize the clinical, laboratory and radiological characteristics of persons with HIV (PWH) presenting with cerebrospinal fluid (CSF) HIV RNA escape.

DESIGN

Retrospective case review of PWH presenting with symptomatic CSF HIV RNA escape at seven tertiary HIV clinical sites in the United Kingdom and Italy.

METHOD

PWH with symptomatic CSF HIV RNA escape episodes were identified and data obtained from medical records. CSF HIV RNA escape was defined as quantifiable CSF HIV RNA in unquantifiable plasma HIV RNA or CSF HIV RNA greater than plasma HIV RNA in cases where plasma HIV RNA was quantifiable. The onset of clinical symptoms was classified as acute (<2 weeks-6 months), or chronic (>6 months) and differences in presentation in those with CSF HIV RNA below and above 1000 copies/ml determined.

RESULTS

We identified 106 PWH with CSF HIV RNA escape (65 male); 68 (64%) PWH had acute presentations and 38 (36%) had chronic presentations. Cognitive decline (n = 54; 50.9%), confusion (n = 20; 18.9%) and headache (n = 28; 26.4%) were the most common presentations, with cognitive decline being more common in PWH who presented chronically compared with PWH who presented acutely (73.7% vs. 35.3%, P = 0.0002). Sixty PWH had CSF HIV RNA at least 1000 copies/ml and presented more frequently with confusion (n = 15/60; 25.0%) compared with PWH with CSF HIV RNA less than 1000 copies/ml at presentation (n = 5/46; 10.9%; P = 0.03).

CONCLUSION

Cognitive decline, confusion and headache are the most frequent presenting symptoms of CSF HIV RNA escape and their relative frequency varied according to symptom onset and CSF HIV RNA concentration.

Analysis of the Effect of Incentive Nursing Intervention in Children with Severe Viral Encephalitis and Myocarditis during Rehabilitation Based on Diffusion Weighted MRI

Background

Severe viral encephalitis in children causes a viral infection that damages their central nervous system. This situation arises the mental abnormalities, sudden rise in body temperature, disturbance of consciousness, and so forth in children, which can be life-threatening.

Objective

This work aimed at exploring the effect of diffusion weighted MRI on children with severe viral encephalitis and myocarditis.

Methods

This work presents a diffusion weighted MRI scanning method that involves scanning through a serial imaging device, axial scanning, and sagittal and coronal scanning. 60 children with severe viral encephalitis and myocarditis who admitted to Brain Hospital of Hunan Province from April 2017 to May 2020 were deemed as research subjects. All the children underwent CT and MRI examination, blood routine examination, and cerebrospinal fluid examination after admission. This work uses the random number table method to classify the subjects into control group and observation group, each consisting of 30 cases. Children in the control group were provided with the routine nursing intervention, whereas children in the observation group were subjected to incentive nursing intervention. The baseline data, ECG monitoring indicators, body abnormalities, and clinical symptom relief time of the two groups of children were compared and the results of diffusion weighted MRI scans were analyzed and the ADC values were counted.

Results

The two groups of children were compared on the basis of baseline data, and the variation was not statistically substantial (P > 0.05). The cases of children in the control group had higher heart rate and respiration, and physical dysfunction, language dysfunction, unconsciousness, and nervous dysfunction were more than those in the observation group. However, the cases of blood oxygen saturation were less than those of the observation group. After nursing intervention done for the control group, remission time of clinical symptoms such as convulsion, physical dysfunction, unconsciousness, and nerve dysfunction was longer relative to the observation group (all P < 0.05 are considered).

Conclusion

The diffusion weighted MRI had diagnostic significance for severe viral encephalitis and myocarditis. For children with severe viral encephalitis and myocarditis, clinical incentive nursing intervention was particularly imperative. It can not only help children to relieve symptoms and control the deterioration of the disease in a short time but also help improve the quality of life of the children and the confidence of family members to cope with the disease.

A rare case of HIV CNS escape in a patient previously considered a viral controller

Human immunodeficiency virus (HIV) ribonucleic acid (RNA) levels generally remain undetectable in the cerebrospinal fluid of people living with HIV with peripheral viral suppression. Secondary HIV central nervous system (CNS) escape refers to the rare independent replication of HIV RNA in the central nervous system despite peripheral viral suppression that occurs in the setting of a concomitant non-HIV infection. We describe here a young man with perinatal HIV infection considered a viral controller who developed secondary HIV CNS escape in the setting of a presumed fungal CNS infection.

Herpes zoster in HIV-1 infection: The role of CSF pleocytosis in secondary CSF escape and discordance

HIV cerebrospinal fluid (CSF) escape is defined by a concentration of HIV-1 RNA in CSF above the lower limit of quantification of the employed assay and equal to or greater than the plasma HIV-1 RNA level in the presence of treatment-related plasma viral suppression, while CSF discordance is similarly defined by equal or higher CSF than plasma HIV-1 RNA in untreated individuals. During secondary CSF escape or discordance, disproportionate CSF HIV-1 RNA develops in relation to another infection in addition to HIV-1. We performed a retrospective review of people living with HIV receiving clinical care at Sahlgrenska Infectious Diseases Clinic in Gothenburg, Sweden who developed uncomplicated herpes zoster (HZ) and underwent a research lumbar puncture (LP) within the ensuing 150 days. Based on treatment status and the relationship between CSF and plasma HIV-1 RNA concentrations, they were divided into 4 groups: i) antiretroviral treated with CSF escape (N = 4), ii) treated without CSF escape (N = 5), iii) untreated with CSF discordance (N = 8), and iv) untreated without CSF discordance (N = 8). We augmented these with two additional cases of secondary CSF escape related to neuroborreliosis and HSV-2 encephalitis and analyzed these two non-HZ cases for factors contributing to CSF HIV-1 RNA concentrations. HIV-1 CSF escape and discordance were associated with higher CSF white blood cell (WBC) counts than their non-escape (P = 0.0087) and non-discordant (P = 0.0017) counterparts, and the CSF WBC counts correlated with the CSF HIV-1 RNA levels in both the treated (P = 0.0047) and untreated (P = 0.002) group pairs. Moreover, the CSF WBC counts correlated with the CSF:plasma HIV-1 RNA ratios of the entire group of 27 subjects (P = <0.0001) indicating a strong effect of the CSF WBC count on the relation of the CSF to plasma HIV-1 RNA concentrations across the entire sample set. The inflammatory response to HZ and its augmenting effect on CSF HIV-1 RNA was found up to 5 months after the HZ outbreak in the cross-sectional sample and, was present for one year after HZ in one individual followed longitudinally. We suggest that HZ provides a ‘model’ of secondary CSF escape and discordance. Likely, the inflammatory response to HZ pathology provoked local HIV-1 production by enhanced trafficking or activation of HIV-1-infected CD4+ T lymphocytes. Whereas treatment and other systemic factors determined the plasma HIV-1 RNA concentrations, in this setting the CSF WBC counts established the relation of the CSF HIV-1 RNA levels to this plasma set-point.

Two treatment strategies for management of Neurosymptomatic cerebrospinal fluid HIV escape in Pune, India

Symptomatic cerebrospinal fluid (CSF) viral escape (sCVE) is reported in people with HIV, who are on ritonavir-boosted protease inhibitor (PI/r) containing antiretroviral therapy (ART). Management of sCVE includes performing genotypic HIV-1 resistance testing (GRT) on CSF and plasma HIV and changing ART accordingly. Neither GRT nor newer drugs (Dolutegravir and Darunavir/ritonavir) are routinely available in India. As a result, management of sCVE includes 2 modalities: a) ART intensification by adding drugs that reach therapeutic concentrations in CSF, like Zidovudine, to existing ART or b) Changing to a regimen containing newer boosted PI/r and integrase strand transfer inhibitor (INSTI) as per GRT or expert opinion. In this retrospective study, we report the outcomes of above 2 modalities in treatment of sCVE in Pune, India.Fifty-seven episodes of sCVE in 54 people with HIV taking PI/r-containing ART were identified. Clinical, demographic, laboratory and ART data were recorded. Forty-seven cases had follow-up data available after ART change including measurement of plasma and CSF viral load (VL).Of the 47 cases, 23 received zidovudine intensification (Group A, median VL: plasma- 290, CSF- 5200 copies/mL) and 24 received PI/INSTI intensification (Group B, median VL: plasma- 265, CSF-4750 copies/mL). CSF GRT was performed in 16 participants: 8 had triple class resistance. After ART change, complete resolution of neurologic symptoms occurred in most participants (Group A: 18, Group B: 17). In Group A, follow-up plasma and CSF VL were available for 21 participants, most of whom achieved virologic suppression (VL < 20 copies/mL) in plasma (17) and CSF (15). Four participants were shifted to the PI/INSTI intensification group due to virologic failure (plasma or CSF VL > 200 copies/mL). In Group B, follow-up plasma and CSF VL were available for 23 participants, most of whom also achieved virologic suppression in plasma (21) and CSF (18). Four deaths were noted, 2 of which were in individuals who interrupted ART.This is a unique sCVE cohort that was managed with 1 of 2 approaches based on treatment history and the availability of GRT. At least 75% of participants responded to either approach with virologic suppression and improvement in symptoms.

What can characterization of cerebrospinal fluid escape populations teach us about viral reservoirs in the central nervous system?

OBJECTIVE

To review the evidence that CSF (cerebrospinal fluid) escape populations are produced by viral reservoirs in the central nervous system (CNS).

DESIGN

CSF escape is a rare phenomenon in which individuals on suppressive ART have well controlled systemic infections with elevated levels of HIV-1 RNA in their CSF. However, the rarity of CSF escape coupled with relatively low CSF viral loads has impeded detailed analyses of these populations. Here, and in a previous study, we performed genetic and phenotypic assessments of CSF escape populations to determine whether CSF escape is produced by CNS reservoirs or by cells trafficking through the CNS.

METHODS

We report HIV-1 viral loads in the CSF and blood plasma of four individuals with CSF escape (one new example and three previously described examples). We performed phylogenetic analyses of the viral env gene to evaluate diversity within the CSF escape populations and performed entry analyses to determine whether Env proteins were adapted to entering macrophage/microglia.

RESULTS

Two individuals had CSF escape produced by CNS reservoirs. In contrast, the remaining two cases were likely because of transient viral production from cells migrating into the CNS and releasing virus.

CONCLUSION

Together our analyses indicate that replication-competent HIV-1 can persist in the CNS during ART, but that not all cases of CSF escape are produced by CNS reservoirs. Our results also suggest that both CD4 T cells and macrophage/microglia can serve as persistent viral reservoirs in the CNS.

Symptomatic cerebrospinal fluid escape

: Cerebrospinal fluid (CSF) viral escape is defined by detectable HIV-RNA in CSF despite undetectable or lower-than-CSF level in plasma of patients receiving combination antiretroviral therapy (cART). This condition may occasionally be associated with neurological problems, consisting of new and progressive cognitive decline and/or focal symptoms and signs, defining the 'symptomatic CSF escape'. Brain MRI usually shows diffuse white matter hyperintensities that recall the presentation of HIV encephalopathy in the precART era. However, patients develop symptomatic CSF escape with relatively high CD4 cell counts and suppressed or low systemic virus replication. In addition, the frequent CSF pleocytosis and the pathological demonstration of CD8 T-cell brain infiltrates in some cases of symptomatic escape indicate that inflammation is an important component in the pathogenesis of this condition. Low nadir CD4 cells are common, likely reflecting the establishment of a HIV reservoir in the central nervous system (CNS). CSF escape seems to result from reactivation of CNS infection when cART potency is lowered, because of low patient's adherence, drug resistance, or use of drug combinations that are poorly effective in the CNS and cART optimization is key to revert escape and neurological disease in the great majority of cases.

Brain MRI Features of CSF Human Immunodeficiency Virus Escape

BACKGROUND AND PURPOSE

HIV infection of the central nervous system (CNS) is a nearly universal feature of untreated systemic HIV infection. While combination antiretroviral therapy (ART) that suppresses systemic infection usually suppresses CNS (CNS) HIV infection, exceptions have been reported with discordance between CSF and blood HIV RNA concentrations such that CSF demonstrates higher HIV concentrations than blood, referred to as CSF HIV escape. Rarely, CSF HIV escape presents with neurological symptoms, called neurosymptomatic escape.

METHODS

In this report, we describe the MRI findings in 6 patients with neurosymptomatic escape who were identified at our institution.

RESULTS

MR imaging suggests an encephalitis possibly evolving from a distinct HIV subpopulation within the CNS. A major difference between primary HIV infection and the current case series is that untreated HIV encephalitis usually occurs in the setting of late disease and a low CD4 whereas CSF Escape develops in setting of a higher CD4, as well as more robust immune and inflammatory responses. Our findings show a burden and distribution of white matter signal abnormalities atypical for patients adherent to ART and that differs from that seen in untreated HIV encephalitis and leukoencephalopathy. Moreover, these patients may also demonstrate perivascular enhancement, a finding not previously reported in the CSF HIV escape literature.

CONCLUSION

Recognition of these imaging characteristics-patchy subcortical white matter intensities and a perivascular pattern of enhancement-may be helpful in recognition and, along with other clinical information and CSF findings, in diagnosis of neurosymptomatic escape.

Cerebrospinal fluid drug concentrations and viral suppression in HIV-1-infected patients receiving ritonavir-boosted atazanavir plus lamivudine dual antiretroviral therapy (Spanish HIV/AIDS Research Network, PreEC/RIS 39)

This study aimed to assess cerebrospinal fluid (CSF) drug concentrations and viral suppression in HIV-1-infected patients on ritonavir-boosted atazanavir (ATV/r) plus lamivudine (3TC) dual therapy. HIV-1-infected adults with suppressed plasma HIV-1 RNA who switched to ATV/r plus 3TC were studied. Total ATV and 3TC concentrations at the end of the dosing interval (C_24h), using a validated LC-MS/MS method, and HIV-1 RNA were measured in paired CSF and plasma samples 12 weeks after switching. Ten individuals were included. Median (range) age was 42.5 (33-70) years, time on ART was 39.5 (11-197) months, and time with plasma HIV-1 RNA < 40 copies/mL was 15.5 (6-46) months. At baseline, CSF HIV-1 RNA was < 40 copies/mL in all patients. Twelve weeks after switching to ATV/r plus 3TC, HIV-1 RNA remained at < 40 copies/mL in both plasma and CSF in 9/10 patients. One patient with suboptimal adherence to ART had HIV-1 RNA rebound in both plasma and CSF. The median CSF-to-plasma concentration ratios of ATV and 3TC were 0.013 and 0.417, respectively. Median ATV C_24h in CSF was 10.4 (3.7-33.4) ng/mL (in vitro ATV IC₅₀ range, 1-11 ng/mL). Median 3TC C_24h in CSF was 43.4 (16.2-99.3) ng/mL (in vitro 3TC IC₅₀ range, 0.68-20.6 ng/mL). Most patients maintained HIV-1 RNA in CSF < 40 copies/mL despite CSF ATV C_24h close to or within the IC₅₀ range in the majority. ATV PK data in CSF should be considered and rigorous patient selection is advisable to assure effective CSF viral suppression with this two-drug simplification regimen.

Human Immunodeficiency Virus in the Brain-Culprit or Facilitator?

Introduction:

Human immunodeficiency virus (HIV) enters the brain early, where it can persist, evolve, and become compartmentalized. Central nervous system (CNS) disease can be attributed to HIV alone or to the complex interplay between the virus and other neurotropic pathogens.

Aim:

The current review aims to describe the direct impact of HIV on the brain as well as its relationship with other pathogens from a practitioner’s perspective, to provide a general clinical overview, brief workup, and, whenever possible, treatment guidance.

Methods:

A review of PubMed was conducted to identify studies on neuropathogenesis of HIV in relation to host responses. Furthermore, the interaction between the CNS pathogens and the host damage responses were revised in the setting of advanced and also well-controlled HIV infection.

Results:

Similar to other pathogens, HIV leads to CNS immune activation, inflammation, and viral persistence. Therefore, almost half of the infected individuals present with neurocognitive disorders, albeit mild. Compartmentalized HIV in the CNS can be responsible in a minority of cases for the dramatic presentation of symptomatic HIV escape. Disruption of the immune system secondary to HIV may reactivate latent infections or allow new pathogens to enter the CNS. Opportunistic infections with an inflammatory component are associated with elevated HIV loads in the cerebrospinal fluid and also with greater cognitive impairment. The inflammatory immune reconstitution syndrome associated with CNS opportunistic infections can be a life-threatening condition, which needs to be recognized and managed by efficiently controlling the pathogen burden and timely balanced combination antiretroviral therapy. Latent neurotropic pathogens can reactivate in the brain and mimic HIV-associated severe neurological diseases or contribute to neurocognitive impairment in the setting of stable HIV infection.

Conclusions:

As HIV can be responsible for considerable brain damage directly or by facilitating other pathogens, more effort is needed to recognize and manage HIV-associated CNS disorders and to eventually target HIV eradication from the brain.

Discordant CSF/plasma HIV-1 RNA in individuals on virologically suppressive antiretroviral therapy in Western India

Aim of this study was to estimate the prevalence of cerebrospinal fluid (CSF)/Plasma HIV-1 RNA discordance in virologically suppressed individuals presenting with incident neurologic symptoms.In this retrospective cohort study conducted between March 1, 2009, and March 1, 2017, HIV-1 infected adults exposed to atleast 12 months of antiretroviral therapy (ART) and having plasma viral load (VL) <1000 copies/mL (virologically suppressed) were included. Among these, individuals presenting with neurologic symptoms during follow-up were assessed for CSF/Plasma HIV-1 RNA discordance by measuring HIV-1 RNA in collected plasma and CSF samples. CSF/plasma HIV-1 RNA discordance was defined as either detectable CSF HIV-1 RNA (VL > 20 copies/mL) with an undetectable plasma RNA (complete viral suppression, VL ≤20 copies/mL) or CSF HIV-1 RNA ≥ 0.5 log10 higher than plasma RNA when plasma VL was between 20 and 1000 copies/mL (low-level viremia, LLV).Out of 1584 virologically suppressed patients, 71 (4.4%) presented with incident neurologic symptoms. Twenty out of 71 (28.2%) patients were diagnosed with CSF/Plasma HIV-1 discordance. Median plasma and CSF VL in patients with discordance was 120 [interquartile range (IQR): <20 to 332.5] and 4250 (IQR: 2550.0- 9615.0) copies/mL, respectively. All 9 individuals in which CSF HIV-1 genotypic resistance testing was done showed mutations that would compromise efficacy of prescribed ART regimen. Prevalence of CSF/plasma HIV-1 RNA discordance was higher among neurologically symptomatic patients with plasma LLV as compared with those with complete viral suppression (70% vs 11.8%, P < .001). The risk of discordance was also greater in patients who received protease inhibitor (PI) containing ART (P < .001) and those on ART regimens with central nervous system (CNS) penetration effectiveness (CPE) value <6 (P = .006).CSF/plasma HIV-1 RNA discordance indicates replication of HIV-1 that has adapted to the CNS or has developed antiretroviral drug resistance. Larger studies should be performed to study incidence of discordance in India. This will help in managing patients presenting with neurologic symptoms on suppressive ART with appropriate neuroeffective therapy.

Neurological Complications of HIV Infection

PURPOSE OF REVIEW

HIV-associated neurocognitive disorders (HAND) are common in patients with HIV disease, even during suppressive combination antiretroviral therapy (cART). This review article addresses the pathogenesis of HAND, focusing on important findings from the last 5 years.

RECENT FINDINGS

While HIV-associated dementia is now rare in settings with cART availability, mild forms of HAND are increasing in prevalence. Biomarkers of cellular injury, such as neurofilament light chain and neopterin, can detect early stages of neuroinflammation associated with HIV infection and are increased even in asymptomatic individuals with chronic HIV infection. Several recent studies form a growing body of evidence that HIV can infect and replicate in monocytes and that blocking monocyte activity can potentially improve neurological outcomes in HIV. Early cART may also prevent HAND. Understanding the multifactorial causes of CNS infection and inflammation is critical to devising treatment and preventive strategies for HAND.

Dual antiretroviral therapy for HIV infection

INTRODUCTION

For two decades, triple combinations of antiretrovirals have been the standard treatment for HIV infection. The challenges of such lifelong therapy include long-term side effects, high costs and reduced drug adherence. The recent advent of more potent and safer antiretrovirals has renewed the interest for simpler HIV regimens. Areas covered: We discuss the pros and cons of dual antiretroviral therapies in both drug-naïve and in treatment-experienced patients with viral suppression (switch strategy). Expert opinion: Some dual antiretroviral regimens are safe and efficacious, particularly as maintenance therapy. At this time, combinations of dolutegravir plus rilpivirine represent the best dual regimen. Longer follow-up and larger study populations are needed before supporting dolutegravir plus lamivudine. In contrast, dual therapy based on maraviroc is less effective. Although dual regimens with boosted protease inhibitors plus either lamivudine or raltegravir may be effective, they are penalized by metabolic side effects and risk for drug interactions. The newest dual regimens could save money, reduce toxicity and spare drug options for the future. For the first time in HIV therapeutics, less can be more. Dual therapy switching has set up a new paradigm in HIV treatment that uses induction-maintenance.

Temporal Patterns and Drug Resistance in CSF Viral Escape Among ART-Experienced HIV-1 Infected Adults

Supplemental Digital Content is Available in the Text.

Background:

Cerebrospinal fluid (CSF) viral escape is an increasingly recognized clinical event among HIV-1-infected adults. We analyzed longitudinal data and drug-resistance mutations to characterize profiles of HIV-1-infected patients on antiretroviral therapy with discordant CSF and plasma HIV-1 RNA levels.

Methods:

Forty-one cases of CSF escape defined as detectable CSF HIV-1 RNA when plasma levels were undetectable, or HIV-1 RNA >0.5-log higher in CSF than plasma were identified from Boston Hospitals and National NeuroAIDS Tissue Consortium (NNTC) from 2005 to 2016.

Results:

Estimated prevalence of CSF escape in Boston and NNTC cohorts was 6.0% and 6.8%, respectively; median age was 50, duration of HIV-1 infection 17 years, CD4 count 329 cells/mm³ and CD4 nadir 21 cells/mm³. Neurological symptoms were present in 30 cases; 4 had repeat episodes of CSF escape. Cases were classified into subtypes based plasma HIV-1 RNA levels in the preceding 24 months: high-level viremia (1000 copies/mL), low-level viremia (LLV: 51–999 copies/mL), and plasma suppression with CSF blip or escape (CSF RNA <200 or ≥200 copies/mL). High-level viremia cases reported more substance abuse, whereas LLV or plasma suppression cases were more neurosymptomatic (81% vs. 53%); 75% of repeat CSF escape cases were classified LLV. M184V/I mutations were identified in 74% of CSF samples when plasma levels were ≤50 copies per milliliter.

Conclusions:

Characteristics frequently observed in CSF escape include HIV-1 infection >15 years, previous LLV, and M184V/I mutations in CSF. Classification based on preceding plasma HIV RNA levels provides a useful conceptual framework to identify causal factors and test therapeutics.

Short Communication: The Impact of Switching from Atripla to Darunavir/Ritonavir Monotherapy on Neurocognition, Quality of Life, and Sleep: Results from a Randomized Controlled Study

We investigated whether a treatment switch from Atripla^® (tenofovir, emtricitabine, and efavirenz) to DRV/r monotherapy may improve neuropsychological performance, health-related quality of life, and sleep function. Virologically suppressed subjects and asymptomatic on Atripla for ≥6 months were randomized 1:1 to continue Atripla or switch to boosted darunavir (DRV/r) 800/100 mg once daily for 48 weeks. Neurocognitive tests, the International HIV Dementia Scale (IHDS), Medical Outcomes Study HIV Health Survey (MOS-HIV), EQ-5D-3L, and the Hospital Anxiety and Depression Scale (HADS) were completed at baseline and at week 48. Sleep function was evaluated at week 48. Twenty-six patients on DRV/r and 31 on Atripla completed the 48-week study. No significant difference in the change in scores from week 0 to week 48 between the two arms was observed in neurocognitive outcomes, IHDS, health outcomes (EQ-5D-3L and QOL), and HADS score. By contrast, the HADS score and sleep quality were both significantly better in the DRV/r arm. In conclusion, switching to DRV/r monotherapy did not affect neurocognitive function or quality of life but improved anxiety, and sleep quality was significantly better than in continued Atripla.

HIV-1 replication in central nervous system increases over time on only protease inhibitor therapy

There are concerns about central nervous system (CNS)-replication of HIV-1 in patients on boosted protease inhibitors. Purpose of this study was to compare HIV-1 viral loads (VLs) from patients treated with only boosted dual protease inhibitor (bdPI), versus combination antiretroviral therapy (cART group), containing two nucleoside analogue reverse transcriptase inhibitors (NRTI) and a third partner. All patients from a large German HIV-treatment cohort with available medication, clinical and demographic data, including results from simultaneous HIV-1 viral load (VL) assessments in cerebrospinal fluid (CSF) and blood plasma, were retrospectively evaluated as controlled cross-sectional study. CSF had been obtained from patients with variable neurological symptoms during 2005-2014. Statistical analysis comprised nonparametric tests, regression and correlation techniques accounting for undetectable quantifications. Statistical analysis comprised nonparametric tests, regression and correlation techniques accounting for undetectable quantifications. Overall, 155 patients were evaluable (bdPI: 24; cART: 131). At time of CSF-collection, both groups were comparable in age, gender, CD4-cell counts, or primary HIV-transmission risks, though bdPI patients were clinically more advanced. The proportion of patients with undetectable HIV-1 (<50 copies/ml) in CSF was lower for bdPI group (25 vs 49.6 %; p = 0.026), but similar in plasma (46 vs 41 %). Median CSF-VL was higher in bdPI group (600 vs 50 copies/ml; p = 0.027) and similar in plasma. Mean VL CSF/plasma ratio was 342.91 for bdPI- and 54.48 for cART patients (p < 0.001). Pearson's regression analysis revealed a trend for an elevated VL-ratio over time within bdPI group. HIV-1 replication was higher and more frequently detectable in CSF from bdPI patients, indicating a worse CNS penetration effectiveness of used boosted PI. Within bdPI group, measured CNS-viral replication was increasing over time, suggesting an over time impaired HIV-1 suppression in CSF.

Cerebrospinal fluid analysis for HIV replication and biomarkers of immune activation and neurodegeneration in long-term atazanavir/ritonavir monotherapy treated patients

BACKGROUND

Cerebrospinal fluid (CSF) viral escape is a concern in ritonavir-boosted protease inhibitors monotherapy. The aim was to assess HIV-RNA, biomarkers of immune activation and neurodegeneration, and atazanavir concentrations in CSF of patients on successful long-term atazanavir/ritonavir (ATV/r) monotherapy.

METHODS

This is a substudy of the multicentric, randomized, open-label, noninferiority trial monotherapy once a day with atazanavir/ritonavir (NCT01511809), comparing the ongoing ATV/r along with 2 nucleoside retrotranscriptase inhibitors (NRTIs) regimen to a simplified ATV/r monotherapy. Patients with plasma HIV-RNA < 50 copies/mL after at least 96 study weeks were eligible.We assessed HIV-RNA, soluble (s)CD14, sCD163, CCL2, CXCL10, interleukin-6, and YKL40 by enzyme-linked immunosorbent assay; neopterin, tryptophan, kynurenine, and neurofilament by immunoassays; and ATV concentrations by liquid chromatography-mass spectrometry in paired plasma and CSF samples. Variables were compared with Wilcoxon rank-sum or Fisher exact test, as appropriate.

RESULTS

HIV-RNA was detected in the CSF of 1/11 patients on ATV/r monotherapy (114 copies/mL), without neurological symptoms, who was successfully reintensified with his previous 2NRTIs, and in none of the 12 patients on ATV/r + 2NRTIs. CSF biomarkers and ATV concentrations did not differ between the 2 arms.

CONCLUSIONS

CSF escape was uncommon in patients on long-term ATV/r monotherapy and was controlled with reintensification.

Cerebrospinal Fluid HIV Escape from Antiretroviral Therapy

CNS infection is a nearly constant facet of systemic CNS infection and is generally well controlled by suppressive systemic antiretroviral therapy (ART). However, there are instances when HIV can be detected in the cerebrospinal fluid (CSF) despite suppression of plasma viruses below the clinical limits of measurement. We review three types of CSF viral escape: asymptomatic, neuro-symptomatic, and secondary. The first, asymptomatic CSF escape, is seemingly benign and characterized by lack of discernable neurological deterioration or subsequent CNS disease progression. Neuro-symptomatic CSF escape is an uncommon, but important, entity characterized by new or progressive CNS disease that is critical to recognize clinically because of its management implications. Finally, secondary CSF escape, which may be even more uncommon, is defined by an increase of CSF HIV replication in association with a concomitant non-HIV infection, as a consequence of the local inflammatory response. Understanding these CSF escape settings not only is important for clinical diagnosis and management but also may provide insight into the CNS HIV reservoir.

Cerebrospinal fluid viral escape and acute encephalitis in a patient on boosted protease inhibitor monotherapy

Although currently available data suffice to support the use of protease inhibitor monotherapy in selected patients, there is concern about the antiviral activity of this regimen in the long term and in viral sanctuaries, such as the central nervous system. We report a case of encephalitis related to viral escape while receiving darunavir/ritonavir monotherapy in a carefully selected patient for participation in a clinical trial.

Cerebrospinal fluid and plasma lopinavir concentrations and viral response in virologically suppressed patients switching to lopinavir/ritonavir monotherapy once daily

BACKGROUND

Lopinavir/ritonavir (LPV/r) monotherapy is used in selected virologically suppressed HIV-infected patients. Some would prefer a once-daily (OD) dose instead of the usual twice-daily dose to favour adherence. However, trough concentrations of the drug in blood and particularly in cerebrospinal fluid (CSF) may not be adequate to maintain viral suppression.

METHODS

Prospective, open-label pilot study to evaluate the efficacy and safety of LPV/r monotherapy OD. HIV-1-infected patients, virologically suppressed for at least 6 months were enrolled. HIV viral load (VL) was determined at baseline and at weeks 4, 8, 12, 16, 24, 36 and 48. Lumbar puncture was performed in a subgroup of patients to evaluate CSF VL and CSF LPV concentrations.

RESULTS

A total of 21 patients were included. At week 48, 85.7% (n=18) showed viral suppression (VL<40 copies/ml). Two patients had viral failure (9.5%) and a third was withdrawn from the study because of gastrointestinal symptoms. Nine patients were enrolled in the substudy. CSF VL was <40 copies/ml in all cases. Median (range) LPV concentration was 9.78 ng/ml (1.93-78.3) in CSF and 1,970 (154-16,700) ng/ml in plasma; the CSF/plasma ratio was 0.004 (0.001-0.186).

CONCLUSIONS

In this small pilot study, LPV/r monotherapy OD maintained plasma HIV RNA suppression at 48 weeks in most patients, with no cases of CSF viral escape. However, CSF LPV concentrations were close to the 50% inhibitory concentration threshold in several patients; hence, this intervention should be avoided in patients with advanced immune suppression and/or those individuals presenting with significant comorbidities such as hepatitis C coinfection.