Drug-induced liver injury secondary to increased levonorgestrel exposure in a patient taking ritonavir.

We report the first published case of a drug induced liver injury (DILI) presumed secondary to a drug-drug interaction between ritonavir and levonorgestrel progestogen-only emergency contraception (POEC). Our patient is a 25-year-old female living with human immunodeficiency virus (HIV), taking antiretroviral therapy (ART) containing tenofovir alafenamide/emtricitabine and darunavir/ritonavir. She was found to have elevated transaminases at a routine clinic appointment consistent with hepatocellular DILI. Further investigation found the most likely cause of this was a drug-drug interaction (DDI) between the ritonavir component of her ART and recent use of levonorgestrel POEC 3 days earlier. Evidence suggests that ritonavir increases levonorgestrel exposure, yet our patient received double the usual dose as per dispensing guidance at the time. We review the pharmacokinetics of ritonavir-levonorgestrel DDIs and highlight the need for consistent guidelines on this topic.

Prognostic value of non-invasive scores based on liver stiffness measurement, spleen diameter and platelets in HIV-infected patients.

BACKGROUND AND AIMS: People living with HIV (PLWH) are at high risk for advanced chronic liver disease and related adverse outcomes. We aimed to validate the prognostic value of non-invasive scores based on liver stiffness measurement (LSM) and on markers of portal hypertension (PH), namely platelets and spleen diameter, in PLWH. METHODS: We combined data from eight international cohorts of PLWH with available non-invasive scores, including LSM and the composite biomarkers liver stiffness-spleen size-to-platelet ratio score (LSPS), LSM-to-Platelet ratio (LPR) and PH risk score. Incidence and predictors of all-cause mortality, any liver-related event and classical hepatic decompensation were determined by survival analysis, controlling for competing risks for the latter two. Non-invasive scores were assessed and compared using area under the receiver operating curve (AUROC). RESULTS: We included 1695 PLWH (66.8% coinfected with hepatitis C virus). During a median follow-up of 4.7 (interquartile range 2.8-7.7) years, the incidence rates of any liver-related event, all-cause mortality and hepatic decompensation were 13.7 per 1000 persons-year (PY) (95% confidence interval [CI], 11.4-16.3), 13.8 per 1000 PY (95% CI, 11.6-16.4) and 9.9 per 1000 PY (95% CI, 8.1-12.2), respectively. The AUROC of LSM was similar to that of the composite biomarkers, ranging between 0.83 and 0.86 for any liver-related event, 0.79-0.85 for all-cause mortality and 0.87-0.88 for classical hepatic decompensation. All individual non-invasive scores remained independent predictors of clinical outcomes in multivariable analysis. CONCLUSIONS: Non-invasive scores based on LSM, spleen diameter and platelets predict clinical outcomes in PLWH. Composite biomarkers do not achieve higher prognostic performance compared to LSM alone.

The clinical presentation of monkeypox: a retrospective case-control study of patients with possible or probable monkeypox in a West London cohort.

OBJECTIVES: Since May 2022, cases of human monkeypox virus (hMPXV) with human-to-human cross-transmission have significantly increased in nonendemic countries. Our aim was to characterize diagnostic features of patients with confirmed and possible monkeypox to guide future risk stratification and to describe a virtual care model. METHODS: We performed a retrospective case-control study of 140 patients assessed and screened for suspected monkeypox; on hMPXV polymerase chain reaction testing, 70 were confirmed positive, and 70 were negative. Data were compared to generate odds ratios of demographic and clinical features. RESULTS: Patients who tested positive were predominantly cis-male (99%) and self-identified as gay, bisexual, and other men who have sex with men (94%). Lymphadenopathy at presentation was associated with a higher likelihood of a positive result (odds ratio [OR] 7.69 [95% confidence interval (CI) 3.58, 16.51]). Patients who tested positive were more likely to have a rash affecting the genital (OR 5.38 [95% CI 2.57, 11.23]) or buttocks/perianal region (OR 3.79 [1.70, 8.45]) than negative controls. A total of 79% of patients were engaged with a virtual ward follow-up. CONCLUSION: These data can inform a risk-based approach to the management of suspected monkeypox in gay, bisexual, and other men who have sex with men populations. Lymphadenopathy at presentation and the location of the rash were more associated with a positive hMPXV result. Health authorities can consider a virtual ward approach in the hMPHXV outbreak.

Identification of hepatitis delta superinfection when investigating transaminitis in HIV/hepatitis B virus co-infection.

Hepatitis delta virus (HDV) is a highly pathogenic virus which can cause rapidly progressive liver disease in individuals with chronic hepatitis B virus and for which treatment options are limited. The incidence of sexually transmitted HDV infection is unknown. Here we report the case of a HDV seronegative man with pre-existent HIV/hepatitis B virus, taking effective tenofovir-containing antiretroviral therapy, who experienced a significant acute transaminitis with HDV antibody seroconversion and viraemia and no other identifiable cause.

Decline in Hepatitis C Virus (HCV) Incidence in Men Who Have Sex With Men Living With Human Immunodeficiency Virus: Progress to HCV Microelimination in the United Kingdom?

BACKGROUND: Modeling of the London hepatitis C virus (HCV) epidemic in men who have sex with men (MSM) and are living with human immunodeficiency virus (HIV) suggested that early access to direct-acting antiviral (DAA) treatment may reduce incidence. With high rates of linkage to care, microelimination of HCV within MSM living with HIV may be realistic ahead of 2030 World Health Organization targets. We examined trends in HCV incidence in the pre- and post-DAA eras for MSM living with HIV in London and Brighton, United Kingdom. METHODS: A retrospective cohort study was conducted at 5 HIV clinics in London and Brighton between 2013 and 2018. Each site reported all acute HCV episodes during the study period. Treatment timing data were collected. Incidence rates and reinfection proportion were calculated. RESULTS: A total of.378 acute HCV infections were identified, comprising 292 first infections and 86 reinfections. Incidence rates of acute HCV in MSM living with HIV peaked at 14.57/1000 person-years of follow-up (PYFU; 95% confidence interval [CI], 10.95-18.20) in 2015. Rates fell to 4.63/1000 PYFU (95% CI, 2.60 to 6.67) by 2018. Time from diagnosis to starting treatment declined from 29.8 (2013) to 3.7 months (2018). CONCLUSIONS: We observed a 78% reduction in the incidence of first HCV episode and a 68% reduction in overall HCV incidence since the epidemic peak in 2015, which coincides with wider access to DAAs in England. Further interventions to reduce transmission, including earlier access to treatment and for reinfection, are likely needed for microelimination to be achieved in this population.

Increased Body Mass Index and Type 2 Diabetes Are the Main Predictors of Nonalcoholic Fatty Liver Disease and Advanced Fibrosis in Liver Biopsies of Patients With Human Immunodeficiency Virus Monoinfection.

BACKGROUND: Liver disease is an important cause of morbidity and mortality in people living with human immunodeficiency virus (PLWH), of which nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized cause. There are limited data investigating NAFLD in HIV monoinfection and histologically defined disease. We aimed to identify who is at risk of fibrosis, NAFLD, and nonalcoholic steatohepatitis (NASH) among PLWH and explore the diagnostic accuracy of noninvasive markers of fibrosis. METHODS: This was a retrospective, cross-sectional, international, multicenter study including patients with HIV monoinfection, without chronic viral hepatitis or other known causes of chronic liver disease, who underwent liver biopsy for abnormal liver biochemistry and/or clinical suspicion of liver fibrosis. RESULTS: A total of 116 patients from 5 centers were included. Sixty-three (54%) had NAFLD, of whom 57 (92%) had NASH. Overall, 36 (31%) had advanced fibrosis (≥F3) and 3 (3%) had cirrhosis. Of the 53 cases without NAFLD, 15 (28%) had advanced fibrosis. Collagen proportionate area was similar between cases with and without NAFLD (3% vs 2%). Body mass index was independently associated with NAFLD (aOR, 1.2; 95% CI, 1.08-1.34), and type 2 diabetes was independently associated with advanced fibrosis (aOR, 3.42; 95% CI, 1.00-11.71). The area under the curve for advanced fibrosis was 0.65 and 0.66 for both NAFLD Fibrosis Score (NFS) and FIB-4. Cutoff values of -1.455 (NFS) and 1.3 (FIB-4) have negative-predictive values of 0.80 and 0.82, respectively. CONCLUSIONS: Advanced fibrosis is strongly associated with type 2 diabetes in PLWH. Serological markers require further optimization.

Interventions to reduce acute hepatitis C virus in HIV-positive MSM.

PURPOSE OF REVIEW: The WHO has set ambitious targets for hepatitis C virus (HCV) elimination by 2030. In this review, we explore the possibility of HCV micro-elimination in HIV-positive (+) MSM, discussing strategies for reducing acute HCV incidence and the likely interventions required to meet these targets. RECENT FINDINGS: With wider availability of directly acting antivirals (DAAs) in recent years, reductions in acute HCV incidence have been reported in some cohorts of HIV+ MSM. Recent evidence demonstrates that treatment in early infection is well tolerated, cost effective and may reduce the risk of onward transmission. Modelling studies suggest that to reduce incidence, a combination approach including behavioural interventions and access to early treatment, targeting both HIV+ and negative high-risk groups, will be required. HCV vaccine trials have not yet demonstrated efficacy in human studies, however phase one and two studies are ongoing. SUMMARY: Some progress towards the WHO HCV elimination targets has been reported. Achieving sustained HCV elimination is likely to require a combination approach including early access to DAAs in acute infection and reinfection, validated and reproducible behavioural interventions and an efficacious HCV vaccine.

Spleen stiffness measurements using point shear wave elastography detects noncirrhotic portal hypertension in human immunodeficiency virus.

To assess the utility of spleen stiffness as a diagnostic tool in individuals with human immunodeficiency virus (HIV) and non-cirrhotic portal hypertension (NCPH).The Philips EPIQ7, a new point shearwave elastography (pSWE) technique, was used to assess liver and spleen stiffness in 3 patient groups. Group 1: HIV and NCPH (n = 11); Group 2: HIV with past didanosine (ddI) exposure without known liver disease or NCPH (n = 5); Group 3: HIV without known liver disease or ddI exposure (n = 9).Groups were matched for age, HIV chronicity, and antiretroviral treatment (including cumulative ddI exposure in Groups 1 and 2). Differences in liver and spleen stiffness (in kPa) between groups were analyzed using the Mann-Whiney U test.Liver and spleen stiffness were both significantly higher in NCPH versus ddI-exposed (P = .019 and P = .006) and ddI-unexposed controls (P = .038 and P < .001). Spleen stiffness was more effective than liver stiffness at predicting NCPH, area under receiver operating characteristic (AUROC) 0.812 versus 0.948. Combining the 2 variables improved the diagnostic performance, AUROC 0.961. The optimal cut-off for predicting NCPH using splenic stiffness was 25.4 kPa, with sensitivity 91%, specificity 93%, positive predictive value (PPV) 91%, negative predictive value (NPV) 93%, positive likelihood ratio 12.73, negative likelihood ratio 0.10. Spleen and liver stiffness scores were strongly correlated (P = .0004, 95% confidence interval [CI] 18, 59).Elevated spleen stiffness is observed in HIV with NCPH and can be quantified easily using pSWE with high diagnostic accuracy. Novel strategies such as pSWE for longitudinal monitoring of patients with HIV and NCPH should be considered.

Monocyte-macrophage activation is associated with nonalcoholic fatty liver disease and liver fibrosis in HIV monoinfection independently of the gut microbiome and bacterial translocation.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is common among people living with HIV. There are limited data available on the pathophysiology of NAFLD and the development of fibrosis in this population. OBJECTIVES: The aim of this study was to investigate the association of bacterial translocation, adipose tissue dysfunction, monocyte activation and gut dysbiosis in patients with HIV monoinfection and NAFLD. METHODS: Cases with biopsy-proven NAFLD and HIV monoinfection were age and sex-matched to HIV-positive and HIV-negative controls. Markers of bacterial translocation [lipopolysaccharide-binding protein (LBP), bacterial DNA and lipopolysaccharide (LPS)], adipose tissue dysfunction (leptin, adiponectin) and monocyte activation (sCD14 and sCD163) were measured by ELISA. Hepatic patterns of macrophage activation were explored with immunohistochemistry. 16 s rRNA sequencing was performed with stool. RESULTS: Thirty-three cases were included (≥F2 fibrosis n = 16), matched to HIV-positive (n = 29) and HIV-negative (n = 17) controls. Cases with NAFLD were more obese (BMI 31.0 ±â€Š4.4 vs. 24.1 ±â€Š2.8 kg/m, P < 0.001) and had significantly increased levels of sCD14, sCD163 and higher leptin to adiponectin ratio vs. HIV-positive controls. Cases with ≥F2 verses < F2 fibrosis had increased sCD14 (1.4 ±â€Š0.4 vs. 1.1 ±â€Š0.3 µg/ml, P = 0.023) and sCD163 (1.0 ±â€Š0.3 vs. 0.8 ±â€Š0.3 µg/ml, P = 0.060), which correlated with waist circumference (sCD14 P = 0.022, sCD163 P = 0.011). Immunohistochemistry showed increased hepatic portal macrophage clusters in patients with fibrosis. No markers of bacterial translocation or changes to the microbiome were associated with NAFLD or fibrosis. CONCLUSION: NAFLD fibrosis stage in HIV monoinfected patients is associated with monocyte activation in the context of obesity, which may be independent of bacterial translocation and gut microbiome.

A comparison of two post-processing analysis methods to quantify cerebral metabolites measured via proton magnetic resonance spectroscopy in HIV disease.

OBJECTIVE: Non-invasive biomarkers to monitor cerebral function in treated human immunodeficiency virus (HIV) disease are required. Cerebral metabolite ratios (CMRs) measured by proton-MR spectroscopy ((1)H-MRS) are a potential biomarker. Here, we compare two post-processing software packages to quantify CMRs. METHODS: Cerebral (1)H-MRS data from 11 HIV-positive subjects before and after antiretroviral therapy intensification with maraviroc were quantified using a java-based version of the MR user interface package (jMRUI) and the totally automatic robust quantitation in nuclear MR (TARQUIN). (1)H-MRS data included N-acetylaspartate (NAA), creatine (Cr), choline (Cho) and myo-inositol (mI) from three cerebral locations. Differences in quantification and clinical associations of CMRs measured by the two packages were evaluated. RESULTS: Mean CMRs were generally lower when measured by TARQUIN than by jMRUI (NAA/Cr, Cho/Cr, mI/Cr ratios of 1.78, 0.83, 0.81 for jMRUI, and 1.27, 0.25, 0.81 for TARQUIN). Longitudinal changes were observed in CMRs in the basal ganglia voxel although these changes were not statistically significant [+7.1% (p = 0.18), +0.0% (p = 0.91) and -6.6% (p = 0.61) and +14.8% (p = 0.18), +17.9% (p = 0.07) and +34.8% (p = 0.17) for NAA/Cr, Cho/Cr and mI/Cr ratios measured by TARQUIN and jMRUI, respectively]. Plasma maraviroc concentration was associated with a decrease in mI/Cr ratio measured via TARQUIN (p = 0.049). CONCLUSION: Although CMRs differed when quantified by jMRUI vs TARQUIN, these differences were consistently observed across three cerebral locations, and clinical associations were evident by both methods. ADVANCES IN KNOWLEDGE: TARQUIN and jMRUI are viable options to use in the post-processing of cerebral MRS data acquired in HIV disease.

HIV-1 CNS in vitro infectivity models based on clinical CSF samples.

BACKGROUND: The concentration of antiretrovirals in CSF is often utilized as a surrogate for CNS drug exposure. This measurement does not consider pharmacodynamic or combinative effects of ART. We have developed a novel endpoint measurement to assess antiretroviral activity of CSF from subjects on ART. METHODS: CSF samples were obtained from patients receiving tenofovir/emtricitabine (245/200 mg once daily) with either rilpivirine (25 mg once daily) or lopinavir/ritonavir/maraviroc (400/100/150 mg twice daily) and HIV-uninfected controls. Antiviral activity of ART-containing CSF was assessed in cell cultures using PBMCs and neuro-derived glial (U87) and astrocyte (373) cell lines. Infectivity model half-maximal inhibitory concentration (IMIC50) values were calculated and expressed as -log2IMIC50. Results were correlated with CSF antiretroviral concentrations. RESULTS: Compared with controls, CSF from both ART studies demonstrated in vitro antiretroviral activity in all models. CSF antiretroviral activity of patients on lopinavir/ritonavir/maraviroc was significantly greater than that of patients on rilpivirine [-log2IMIC50 (95% CI) 4.82 (4.74-4.89) versus 3.43 (3.33-3.54) in PBMCs, 3.06 (2.98-3.15) versus 2.56 (2.46-2.65) in U87 cells and 6.00 (6.11-5.88) versus 4.90 (5.09-4.72) in 373 cells, respectively]. Positive correlations were observed for individual CSF antiretroviral activity in different cellular models with CSF concentrations of rilpivirine (P = 0.040 in 373 cells) and lopinavir (P = 0.048 in 373 cells), but not maraviroc. CONCLUSIONS: Antiviral activity of CSF from patients on ART was successfully calculated and was greater with a regimen containing four active drugs compared with three active drugs. The use of neuro-derived cell lines alongside PBMCs to assess the effect of ART on CSF may act as a useful future clinical research tool.

Differences in the variability of cerebral proton magnetic resonance spectroscopy (1H-MRS) measurements within three HIV-infected cohorts.

INTRODUCTION: Cerebral functional impairment remains prevalent in effectively treated HIV-infected subjects. As the results of formal cognitive testing are highly variable, surrogate markers to accurately measure cerebral function parameters are needed. Such markers include measurement of cerebral metabolite ratios (CMR) using proton magnetic resonance spectroscopy (1H-MRS). However, data on the inter-subject variability of CMR are sparse. Our aim was to assess inter-subject variability in CMRs within three different HIV-infected cohorts. METHODS: Cerebral 1H-MRS was performed using a Phillips Achieva™ 1.5 Tesla magnetic resonance scanner in HIV-infected subjects as follows: 12 subjects before (group 1) and after intensification of antiretroviral therapy with maraviroc (group 2) and 13 subjects with acute viral hepatitis C (HCV) co-infection (group 3). The coefficients of variation (CV) for CMRs in each group were determined and compared using non-parametric tests to determine whether the inter-subject variability differed significantly. All baseline characteristics between the groups were similar. RESULTS: Overall CVs for all CMRs in groups 1, 2 and 3 were 32.3%, 33.2% and 23.4%, respectively (group 1 vs. 2, p=0.863; group 1 vs. 3, p=0.076). On testing for differences in variability between individual CMRs, two metabolites in the right basal ganglia (RBG) had statistically significantly different CVs when comparing group 1 with group 3: N-acetyl aspartate/creatine (NAA/Cr), p=0.029 and myo-Inositol/creatine (mI/Cr), p=0.016. CONCLUSION: The variability of 1H MRS-measurable CMRs in HIV-infected individuals was lower in those with acute HCV co-infection (group 3).We can conclude that the use of these CMRs in 1H MRS imaging in patients with HIV/acute HCV co-infection is more reliable to assess cerebral function than in patients with HIV infection alone. This has implications for future sample size estimations.

Cerebral function in perinatally HIV-infected young adults and their HIV-uninfected sibling controls.

BACKGROUND: Perinatally acquired HIV-infected (PaHIV) young adults undergo neurodevelopment in the presence of HIV infection and antiretroviral therapy, which may lead to neurocognitive (NC) impairment. Knowledge of NC function in this group is sparse and control data lacking. We compared cerebral function in young adults with PaHIV infection to aged matched HIV negative family controls. METHODS: 16-25-year-old PaHIV young adults (Group 1, n = 33) and HIV-uninfected family controls (Group 2, n = 14) were recruited. Cerebral function was evaluated by: a computerized battery assessing NC function (CogState(TM)), International HIV Dementia Scale (IHDS) and the prospective and retrospective memory questionnaire (PRMQ). Eight cases and four controls also underwent (1)H cerebral magnetic resonance spectroscopy ((1)H-MRS) scanning measuring basal ganglia (BG) metabolites. Cases and controls were compared. RESULTS: Group 1 mean (SD) CD4 count; 444 (319) cells/µl, plasma HIV viral load < 50 in 55%. There were no statistically significant differences between study groups in NC function or IHDS results (P>0.27 all observations). PRMQ scores were significantly higher (42 versus 35, P = 0.02) and MRS BG inflammatory-metabolites (choline- and myo-inositol- to creatine ratios) were significantly greater in Group 1 versus Group 2 (0.83 versus 0.63, P = 0.02 and 3.43 versus 3.03.P = 0.09 respectively). No significant association between PRMQ score and MRS metabolites was observed (P = 0.89). CONCLUSION: Statistically significant differences in cerebral function parameters were observed in PaHIV young adults compared to a well-matched control population. The cognitive deficit observed, in memory, rather than fine motor function, differs from the cerebral impairment often reported in HIV-infected adults.

Increased microglia activation in neurologically asymptomatic HIV-infected patients receiving effective ART.

BACKGROUND: Neuroinflammation plays an important role in HIV-associated neurological disorders; however, its role prior to the onset of symptomatic disease is unclear. We imaged microglial activation, the hallmark of neuroinflammation, in asymptomatic HIV-infected patients on effective combination ART. METHODS: Seven neurologically and cognitively asymptomatic adults with chronic HIV-infection and nine healthy volunteers were investigated with [11C]-PK11195 PET, a marker of translocator protein (TSPO) expressed by activated microglia. In the HIV-infected patients, cognitive speed, accuracy and executive function were also assessed. Between-group differences in [11C]-PK11195 binding potential were localized throughout the brain with statistical parametric mapping (SPM) and associations between levels of [11C]-PK11195 binding and cognitive performance were interrogated using linear regression modelling. RESULTS: In HIV-infected patients, Statistical parametric mapping detected clusters of significantly increased [11C]-PK11195 binding in corpus callosum (P = 0.001), anterior cingulate (P = 0.001), posterior cingulate (P = 0.008) and temporal (P = 0.026) and frontal (P = 0.038) areas. Cognitive functions were intact in the HIV group, however, a significant association between greater [11C]-PK11195 binding and poorer executive function performance was observed in the anterior cingulate (P = 0.031), corpus callosum and posterior cingulate (P = 0.001). CONCLUSION: Despite effective control of HIV infection, neuroinflammation, as evidenced by the presence of focal cortical areas of activated microglia, occurs in asymptomatic HIV-infected patients and levels correlate with poorer executive performance. Further studies are needed to establish whether detection of activated microglia in HIV-infected patients represents a marker of future neurocognitive decline.

The impact of HIV-1 reverse transcriptase polymorphisms on responses to first-line nonnucleoside reverse transcriptase inhibitor-based therapy in HIV-1-infected adults.

OBJECTIVE: HIV-1 genetic variability may influence antiretroviral therapy (ART) outcomes. The study aim was to determine the impact of polymorphisms in regions known to harbor major nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance mutations (codons 90-108, 135-138, 179-190, 225-348) on virologic responses to first-line NNRTI-based ART. METHODS: Reverse transcriptase sequences from ART-naive individuals who commenced efavirenz (EFV) or nevirapine (NVP) with at least two nucleos(t)ide reverse transcriptase inhibitors (NRTIs) without major drug resistance mutations were analyzed. The impact of polymorphisms on week 4 viral load decrease and time to virologic failure was measured over a median 97 weeks. RESULTS: Among 4528 patients, most were infected with HIV-1 subtype B (67%) and commenced EFV-based ART (84%). Overall, 2598 (57%) had at least one polymorphism, most frequently at codons 90, 98, 101, 103, 106, 135, 138, 179, and 238. Virologic failure rates were increased in patients with two (n = 597) or more than two (n = 72) polymorphisms [adjusted hazard ratio 1.43; 95% confidence interval (CI) 1.07-1.92; P = 0.016]. Polymorphisms associated with virologic failure occurred at codons 90 (mostly V90I), 98 (mostly A98S), and 103 (mostly K103R), with adjusted hazard ratios of 1.78 (1.15-2.73; P = 0.009), 1.55 (1.16-2.08; P = 0.003), and 1.75 (1.00-3.05: P = 0.049), respectively. Polymorphisms at codon 179, especially V179D/E/T, predicted reduced week 4 responses (P = 0.001) but not virologic failure. CONCLUSION: The occurrence of multiple polymorphisms, though uncommon, was associated with a small increase in the risk of NNRTI treatment failure; significant effects were seen with polymorphisms at codon 90, 98, and 103. The mechanisms underlying the slower suppression seen with V179D/E/T deserve further investigation.

Alterations in cerebrospinal fluid chemokines are associated with maraviroc exposure and in vivo metabolites measurable by magnetic resonance spectroscopy.

BACKGROUND: Cerebrospinal (CSF) fluid biomarkers may be a useful tool for assessing the cerebral effects of antiretroviral therapy. OBJECTIVE: The aim of the study was to investigate the relationship between 4 CSF chemokines with maraviroc exposure and cerebral metabolite ratios (CMR) measured by magnetic resonance spectroscopy (1H-MRS) in HIV-infected individuals following maraviroc intensification. METHODS: CSF concentration of maraviroc and 4 chemokines (MCP-1, IP-10, MCP-4, and MIP-1ß), plasma concentration of maraviroc pre-CSF assessment, and right basal ganglia CMR were assessed in 12 male HIV-infected, neuro-asymptomatic adults after 14 days of antiretroviral therapy intensification with maraviroc 150 mg twice daily. The relationship between CSF analytes with both CMRs and plasma and CSF maraviroc concentrations were examined using Spearman correlation coefficient. RESULTS: Twelve subjects completed study procedures with baseline values as follows: mean (SD) age 42 (8) years, CD4+ cell count 503 (199) cells/µL, and plasma HIV RNA<50 copies/mL in most subjects. Mean (range, pg/mL) chemokine concentrations were IP-10, 1242 (190-8073); MCP-4, 6.52 (1-18); MCP-1, 702 (201-1618); and MIP-1ß, 42 (5-153). IP-10, MCP-4, and MIP-1ß were significantly associated with CMRs in the right basal ganglia with (1) lower concentrations of IP-10 correlating with higher N-acetyl aspartate to creatine ratios (NAA/Cr) and (2) higher concentrations of MCP-4 and MIP-1ß correlating with higher myoinositol to creatine (mI/Cr) ratios. There were no significant associations with MCP-1. Finally lower concentrations of IP-10 were significantly associated with higher maraviroc plasma trough concentration (r=-0.629, P=.028) but not CSF concentration (r=-0.308, P=.331). CONCLUSION: We hypothesize that the relationship between IP-10, MCP-4, and MIP-1ß with maraviroc exposure and CMRs may be associated with a direct cerebral effect of maraviroc.

Acute HCV/HIV coinfection is associated with cognitive dysfunction and cerebral metabolite disturbance, but not increased microglial cell activation.

BACKGROUND: Microglial cell activation and cerebral function impairment are described in both chronic hepatitis C viral (HCV) and Human-Immune-Deficiency viral (HIV) infections. The aim of this study was to investigate the effect of acute HCV infection upon cerebral function and microglial cell activation in HIV-infected individuals. METHODS: A case-control study was conducted. Subjects with acute HCV and chronic HIV coinfection (aHCV) were compared to matched controls with chronic HIV monoinfection (HIVmono). aHCV was defined as a new positive plasma HCV RNA within 12 months of a negative RNA test. Subjects underwent neuro-cognitive testing (NCT), cerebral proton magnetic resonance spectroscopy ((1)H-MRS) and positron emission tomography (PET) using a (11)C-radiolabeled ligand (PK11195), which is highly specific for translocator protein 18 kDA receptors on activated microglial cells. Differences between cases and controls were assessed using linear regression modelling. RESULTS: Twenty-four aHCV cases completed NCT and (1)H-MRS, 8 underwent PET. Of 57 HIVmono controls completing NCT, 12 underwent (1)H-MRS and 8 PET. Subjects with aHCV demonstrated on NCT, significantly poorer executive function (mean (SD) error rate 26.50(17.87) versus 19.09(8.12), p = 0.001) and on (1)H-MRS increased myo-inositol/creatine ratios (mI/Cr, a marker of cerebral inflammation) in the basal ganglia (ratio of 0.71(0.22) versus 0.55(0.23), p = 0.03), compared to subjects with HIVmono. On PET imaging, no difference in (11)C-PK11195 binding potential (BP) was observed between study groups (p>0.10 all cerebral locations), however lower BPs were associated with combination antiretroviral therapy (cART) use in the parietal (p = 0.01) and frontal (p = 0.03) cerebral locations. DISCUSSION: Poorer cognitive performance and disturbance of cerebral metabolites are observed in subjects with aHC,V compared to subjects with HIVmono. Higher (11)C-PK11195 BP was not observed in subjects with aHCV, but was observed in subjects not on cART.