Diagnostic value of serological biomarkers for detection of non-alcoholic fatty liver disease (NAFLD) and/or advanced liver fibrosis in people living with HIV

The prevalence of nonalcoholic fatty liver disease in people living with HIV: a systematic review and meta-analysis

BACKGROUND

Owing to long-term antiretroviral therapy (ART), the incidence of non-HIV-related chronic diseases is increasing, and liver disease is the leading cause of increased AIDS mortality. Moreover, the prevalence of NAFLD and liver fibrosis has been reported to vary widely across regions and studies. There is no precise description of the trend and characteristics of NAFLD in PLWH. Here, we aimed to explore the prevalence and outcomes of NAFLD in people living with HIV (PLWH).

METHODS

The PubMed, Web of Science, Embase, and Cochrane Library databases were searched on August 15, 2023, for studies that evaluated the prevalence of NAFLD or liver fibrosis among PLWH. The meta-synthesized effects of NAFLD and liver fibrosis were the primary outcomes, and potential moderators were the secondary outcomes. The meta-analysis of the combined event rate (ER) and random effects was conducted on the basis of the number of individuals with NAFLD, the number of individuals with liver fibrosis, and the total sample size.

RESULTS

Of the 3520 studies identified, 41 studies were eligible for the meta-analysis. The results revealed that the combined ERs of NAFLD and liver fibrosis were 0.38 (95% CI: 0.33-0.43, p < 0.01) and 0.25 (95% CI: 0.18-0.32, p < 0.01), respectively.

CONCLUSIONS

This meta-analysis provided empirical evidence that the prevalence of NAFLD and liver fibrosis in PLWH is greater than that in the general population, which requires sufficient attention. In the HIV population, noninvasive imaging to monitor NAFLD changes should be strengthened, and a high TG level might be an early predictive indicator for HIV-associated fatty liver disease; however, large-scale prospective clinical research data are still needed for further validation and evaluation.

Burden of liver steatosis and liver fibrosis in a large cohort of people living with HIV

BACKGROUND

Liver steatosis (LS) and liver fibrosis (LF) can increase the risk of cardiovascular disease in people with HIV, but their prevalence and associated factors are poorly understood. This study aimed to assess the prevalence of and factors associated with LS and LF in a large cohort of people with HIV.

METHODS

We conducted a cross-sectional study of consecutive people with HIV attending the Clinic of Barcelona from September 2022 to September 2023, excluding those with chronic B or/and C hepatitis virus coinfection. LS was assessed using the Hepatic Steatosis Index (HSI) and Fatty Liver Index (FLI), and LF was assessed using the Non-Alcoholic Fatty Liver Disease Fibrosis Score (NFS), Fibrosis-4 score (FIB-4), and the European AIDS Clinical Society (EACS) algorithm in both the whole cohort (cohort 1) and in a specific cohort more susceptible to liver disease (cohort 2). We identified independent variables associated with LS and LF using logistic regression.

RESULTS

Cohort 1 included 4664 people with HIV; 76% and 37% of them had available HSI and FLI data, LS was present in 28% and 19%, respectively. LF risk was present in 1%, 2%, and 1% of people with HIV according to NFS, FIB-4, and EACS algorithm scores, respectively. Cohort 2 included 1345 people with HIV; 60% and 30% of them had available HSI and FLI data, LS affected 55% and 43% and LF 2%, 5%, or 3%, respectively. Factors associated with LS included current CD4 cell count, diabetes, and hypertension, whereas LF was associated with previous exposure to dideoxynucleoside drugs and current CD4 to LF. Current integrase strand transfer inhibitor (INSTI) therapy appeared protective for LF in cohort 1.

CONCLUSIONS

In this study, one in four people with HIV had LS, and the prevalence rose to one in two in those with cardiovascular risk factors. The prevalence of LF was low, but it should be considered in older people with HIV with low CD4 counts or high aspartate transaminase levels. A possible protective effect from INSTIs deserves further investigation.

Global Prevalence of Nonalcoholic Fatty Liver Disease: An Updated Review Meta-Analysis comprising a Population of 78 million from 38 Countries

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a global health challenge, with a rising rate in line with other metabolic diseases. We aimed to assess the global prevalence of NAFLD in adult and pediatric populations.

METHODS

PubMed, Scopus and Web of Science databases were systematically searched up to May 2023. Heterogeneity was assessed using Cochran's Q test and I2 statistics, and random-effects model was used for meta-analysis. Analyses were performed using STATA version 18.

RESULTS

A total of 479 studies with 78,001,755 participants from 38 countries were finally included. The global prevalence of NAFLD was estimated to be 30.2% (95% CI: 28.7-31.7%). Regionally, the prevalence of NAFLD was as follows: Asia 30.9% (95% CI: 29.2-32.6%), Australia 16.1% (95% CI: 9.0-24.8%), Europe 30.2% (95% CI: 25.6-35.0%), North America 29% (95% CI: 25.8-32.3%), and South America 34% (95% CI: 16.9-53.5%). Countries with a higher human development index (HDI) had significantly lower prevalence of NAFLD (coefficient = -0.523, p = 0.005). Globally, the prevalence of NAFLD in men and women was 36.6% (95% CI: 34.7-38.4%) and 25.5% (95% CI: 23.9-27.1%), respectively. The prevalence of NAFLD in adults, adults with obesity, children, and children with obesity was 30.2% (95% CI: 28.8-31.7%), 57.5% (95% CI: 43.6-70.9%), 14.3% (95% CI: 10.3-18.8%), and 38.0% (95% CI: 31.5-44.7%), respectively.

CONCLUSION

The prevalence of NAFLD is remarkably high, particularly in countries with lower HDI. This substantial prevalence in both adults and children underscores the need for disease management protocols to reduce the burden.

External Validation of Serologic Scores for the Detection of Liver Steatosis Among People With HIV

Background

Fatty liver index (FLI) and hepatic steatosis index (HSI) are serologic scores used to detect liver steatosis. However, their diagnostic performance in people with HIV (PWH) remains unclear. We performed an external validation of FLI and HSI in the Swiss HIV Cohort Study.

Methods

We systematically performed vibration-controlled transient elastography (VCTE) among Swiss HIV Cohort Study participants at Bern University Hospital between November 2019 and August 2021. Individuals with viral hepatitis and pregnant women were excluded. We defined liver steatosis as controlled attenuation parameter ≥248 dB/m using VCTE. Model discrimination was assessed with the C-index and model calibration with calibration plots. A decision curve analysis was performed to compare the clinical usefulness of both scores.

Results

Of 321 participants, 91 (28.4%) were female, the median age was 51.4 years (IQR, 42-59), 230 (71.7%) were Caucasian, and 164 (51.1%) had a body mass index >25 kg/m2. VCTE-confirmed liver steatosis was present in 158 (49.2%). Overall, 125 (38.9%) had an FLI ≥60, and 128 (39.9%) had an HSI ≥36. At these cutoffs, the C-index to diagnose liver steatosis was 0.85 for FLI (95% CI, .80-.89) and 0.78 for HSI (95% CI, .73-.83). Whereas FLI was well calibrated, HSI overestimated the risk for steatosis. Both models showed a positive net benefit, with FLI having a greater net benefit when compared with HSI.

Conclusions

FLI and HSI are valid tools to detect liver steatosis in PWH. FLI should be the preferred score, given its better performance and greater clinical usefulness.

Steatotic liver disease and HIV: an agenda for 2030

People living with HIV are particularly susceptible to developing metabolic disorders, including metabolic dysfunction-associated steatotic liver disease and other forms of SLD. However, people living with HIV have been historically excluded from clinical trials and large cohort studies of SLD. Therefore, our understanding of the risk factors and natural history of SLD in this population is poor. Moreover, relevant knowledge gaps on the epidemiology and barriers for adequate health care, such as stigma, hamper adequate responses to the ongoing HIV and SLD syndemic. This Viewpoint provides a comprehensive perspective on how to tackle SLD in people living with HIV by examining the role of social determinants of health in the development of liver disease and metabolic syndrome comorbidities among this population, emphasising the importance of prioritising SLD management, summarising the most urgent needs in the field, and offering recommendations for advancing research to fill key data gaps and protect liver health of people living with HIV.

Diagnostic Ability of Simple Noninvasive Blood Tests to Predict Increased Liver Stiffness in People Living With HIV and Steatotic Liver Disease

INTRODUCTION

Steatotic liver disease is common in people with HIV (PWH). Identifying those with advanced fibrosis (AF, bridging fibrosis or cirrhosis), F3-4, is important. We aimed to examine the performance of FIB-4 and nonalcoholic fatty liver disease (NAFLD) fibrosis score (NFS) in PWH to identify those with AF assessed by liver stiffness measurement (LSM).

METHODS

We prospectively collected data on adults participating in 2 National Institute of Health-sponsored HIV NAFLD networks. All had HIV on antiretroviral therapy (ART) ≥6 months with HIV RNA <200 copies/mL. Those with viral hepatitis, other liver disease, excessive alcohol use, or hepatic decompensation were excluded. Vibration-controlled transient elastrography for LSM was performed, and AF defined as ≥11 kPa was compared with FIB-4 and NFS at predefined thresholds (<1.3 and >2.67 for FIB-4 and <-1.455 and >0.675 for NFS).

RESULTS

A total of 1,065 participants were analyzed: mean age 51.6 years, 74% male, 28% White, 46% Black, 22% Hispanic, with 34% overweight (body mass index 25-29 kg/m 2 ) and 43% obese (body mass index ≥30 kg/m 2 ). Features of the metabolic syndrome were common: hyperlipidemia 35%, type 2 diabetes 17%, and hypertension 48%. The median CD4 + T-cell count was 666 cells/mm 3 , 74% had undetectable HIV RNA, and duration of HIV-1 was 17 years with most taking a nucleoside reverse transcriptase inhibitor (92%) and an integrase inhibitor (83%). The mean LSM was 6.3 kPa, and 6.3% had AF. The area under the receiver characteristic curve for FIB-4 and NFS to identify AF were 0.70 and 0.75, respectively. While both had high negative predictive values (97%-98%), the sensitivity at low thresholds and specificity at high thresholds were 64% and 97% for FIB-4 and 80% and 96% for NFS, respectively. Neither FIB-4 nor NFS at either threshold had good positive predictive value to detect AF.

DISCUSSION

FIB-4 and NFS have excellent specificity and negative predictive value for detecting AF, and thus can be used as screening tools in PWH to exclude those with AF who do not need further testing (LSM) or referral to hepatologist.

Prevalence and risk factors of metabolic dysfunction-associated steatotic liver disease in south Central Uganda: A cross-sectional survey

BACKGROUND

Despite numerous risk factors and serious consequences, little is known about metabolic dysfunction-associated steatotic liver disease (MASLD) at population level in Africa.

AIM

The aim of the study was to estimate the prevalence and risk factors of MASLD in people living with and without HIV in Uganda.

METHODS

We collected data from 37 communities in South Central Uganda between May 2016 and May 2018. We estimated MASLD prevalence using the fatty liver index and advanced liver fibrosis using the dynamic aspartate-to-alanine aminotransferase ratio. We collected additional data on sociodemographics, HIV and cardiovascular disease (CVD) risk factors. We used multivariable logistic regression to determine the association between HIV, CVD risk factors and MASLD.

RESULTS

We included 759 people with HIV and 704 HIV-negative participants aged 35-49. MASLD prevalence was 14% in women and 8% in men; advanced liver fibrosis prevalence was estimated to be <1%. MASLD prevalence was more common in women (15% vs. 13%) and men (9% vs. 6%) with HIV. Being female (odds ratio [OR] = 2.1; 95% confidence interval [CI] = 1.4-3.3) was associated with a higher odds of MASLD after adjustment for confounders; HIV infection was borderline associated with MASLD (OR = 1.4; 95% CI: 1.0-2.0).

CONCLUSIONS

In a relatively young cohort in Uganda, 14% of women and 8% of men had MASLD. There was an indication of an association between HIV and MASLD in multivariable analysis. These data are the first to describe the population-level burden of MASLD in sub-Saharan Africa using data from a population-based cohort.

Fatty Liver Disease: Enter the Metabolic Era

PURPOSE OF REVIEW

The goal of this review is to summarize the recent literature linking HIV to metabolic dysfunction-associated steatotic liver disease (MASLD). This is a pressing issue due to the scale of the MASLD epidemic and the urgent need for preventive and therapeutic strategies for MASLD in PWH.

RECENT FINDINGS

The prevalence of MASLD in PWH is higher than previously appreciated, approaching 50% depending on the population and definition of MASLD. MASLD in PWH is likely multifactorial due to risk factors present in the general population such as metabolic syndrome, and features unique to HIV including systemic inflammation and ART. Statin therapy results in a significant reduction in major adverse cardiovascular events in PWH. PWH are at high risk for MASLD. Screening PWH with metabolic syndrome features could enable earlier interventions to reduce morbidity and mortality associated with MASLD in PWH.

Innovative Therapeutic Approaches in Non-Alcoholic Fatty Liver Disease: When Knowing Your Patient Is Key

Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disorders ranging from simple steatosis to non-alcoholic steatohepatitis (NASH). Hepatic steatosis may result from the dysfunction of multiple pathways and thus multiple molecular triggers involved in the disease have been described. The development of NASH entails the activation of inflammatory and fibrotic processes. Furthermore, NAFLD is also strongly associated with several extra-hepatic comorbidities, i.e., metabolic syndrome, type 2 diabetes mellitus, obesity, hypertension, cardiovascular disease and chronic kidney disease. Due to the heterogeneity of NAFLD presentations and the multifactorial etiology of the disease, clinical trials for NAFLD treatment are testing a wide range of interventions and drugs, with little success. Here, we propose a narrative review of the different phenotypic characteristics of NAFLD patients, whose disease may be triggered by different agents and driven along different pathophysiological pathways. Thus, correct phenotyping of NAFLD patients and personalized treatment is an innovative therapeutic approach that may lead to better therapeutic outcomes.

The human microbiome and gut-liver axis in people living with HIV

PURPOSE OF REVIEW

Chronic liver disease is a major cause of morbidity and mortality amongst people living with HIV (PLWH). Emerging data suggests that gut microbial translocation may play a role in driving and modulating liver disease, a bi-directional relationship termed the gut-liver axis. While it is recognized that PLWH have a high degree of dysbiosis and gut microbial translocation, little is known about the gut-liver axis in PLWH.

RECENT FINDINGS

Recent studies have shown that microbial translocation can directly lead to hepatic inflammation, and have linked gut microbial signatures, dysbiosis, and translocation to liver disease in PLWH. Additionally, multiple trials have explored interventions targeting the microbiome in PLWH. Emerging research supports the interaction between the gut microbiome and liver disease in PLWH. This offers new opportunities to expand our understanding of the pathophysiology of liver disease in this population, as well as to explore possible clinical interventions.

Predictive plasma biomarkers of long-term increase in hepatic steatosis index after HCV eradication in HIV/HCV-coinfected patients

Hepatic steatosis is a common condition found in the liver of hepatitis C virus (HCV)-infected patients, contributing to more severe forms of liver disease. In addition, the human immunodeficiency virus (HIV) may accelerate this process. Alternatively, several immune checkpoint proteins have been reported to be upregulated and correlated with disease progression during HCV and HIV infections. In steatosis, a detrimental immune system activation has been established; however, the role of the immune checkpoints has not been addressed so far. Thus, this study aimed to evaluate the association between plasma immune checkpoint proteins at baseline (before antiviral therapy) with hepatic steatosis index (HSI) increase at the end of follow-up (∼ five years after sustained virologic response (SVR)). We performed a multicenter retrospective study in 62 patients coinfected with HIV/HCV who started antiviral therapy. Immune checkpoint proteins were analyzed at baseline using a Luminex 200TM analyzer. The statistical association analysis was carried out using Generalized Linear Models (GLM) and Partial Least Squares Discriminant Analysis (PLS-DA). Fifty-three percent of the patients showed HSI increase from baseline to the end of follow-up. Higher immune checkpoint protein levels of BTLA, CD137(4-1BB), CD80, GITR, LAG-3, and PD-L1 before HCV therapy were associated with a long-term increase in HSI after successful HCV therapy, suggesting a potential predictive role for early detection of progression towards steatosis in HIV/HCV-coinfected patients.

Prevalence of non-alcoholic fatty liver disease in a multicentre cohort of people living with HIV in Spain

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is one of the most important liver comorbidities in people living with HIV (PLWH). Factors that could lead to a higher prevalence of NAFLD or ease the onset of fibrosis are unclear.

METHODS

Cohort study of the Spanish HIV Research Network, which comprehends 46 hospitals and more than 15,000 PLWH. Primary objectives were to assess NAFLD prevalence and liver fibrosis according to hepatic steatosis index (HSI) and NAFLD fibrosis score, respectively. Factors associated with both were analysed.

RESULTS

A total of 4798 PLWH were included of whom 1461 (30.5%) showed an HSI>36; these patients had higher risk for significant fibrosis (OR 1.91; 95%CI 1.11-3.28). Factors associated with NAFLD were body mass index (OR 2.05; 95%CI 1.94-2.16) and diabetes (OR 4.68; 95%CI 2.17-10.08), while exposure to integrase strand transfer inhibitors showed a lower risk (OR 0.78; 95%CI 0.62-0.97). In patients with HSI>36, being female (OR 7.33; 95%CI 1.34-40), age (OR 1.22; 95%CI 1.11-1.34), body mass index (OR 1.35; 95%CI 1.18-1.54) and exposure to thymidine analogues (OR 75.4, 95%CI 6.9-823.5) were associated with a higher risk of significant fibrosis. However, exposure to non-nucleoside reverse transcriptase inhibitors (OR 0.12, 95%CI 0.02-0.89) and time of exposure to protease inhibitors (OR 0.97, 95%CI 0.95-1) showed a lower risk.

CONCLUSION

NAFLD prevalence was high in our cohort. Patients exposed to INSTI showed a lower risk of NAFLD. In patients with hepatic steatosis, exposure to thymidine analogues had 75-fold more risk of significant fibrosis while exposure to NNRTIs reduced this risk.

Development and validation of an online dynamic nomogram based on the atherogenic index of plasma to screen nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD), a common liver disease worldwide, can be reversed early in life with lifestyle and medical interventions. This study aimed to develop a noninvasive tool to screen NAFLD accurately.

METHODS

Risk factors for NAFLD were identified using multivariate logistic regression analysis, and an online NAFLD screening nomogram was developed. The nomogram was compared with reported models (fatty liver index (FLI), atherogenic index of plasma (AIP), and hepatic steatosis index (HSI)). Nomogram performance was evaluated through internal and external validation (National Health and Nutrition Examination Survey (NHANES) database).

RESULTS

The nomogram was developed based on six variables. The diagnostic performance of the present nomogram for NAFLD (area under the receiver operator characteristic curve (AUROC): 0.863, 0.864, and 0.833, respectively) was superior to that of the HSI (AUROC: 0.835, 0.833, and 0.810, respectively) and AIP (AUROC: 0.782, 0.773, and 0.728, respectively) in the training, validation, and NHANES sets. Decision curve analysis and clinical impact curve analysis presented good clinical utility.

CONCLUSION

This study establishes a new online dynamic nomogram with excellent diagnostic and clinical performance. It has the potential to be a noninvasive and convenient method for screening individuals at high risk for NAFLD.

Liver Inflammation Is Common and Linked to Metabolic Derangements in Persons With Treated Human Immunodeficiency Virus (HIV)

BACKGROUND

We sought to characterize in people with human immunodeficiency virus (PWH) the potential etiologies of elevated alanine aminotransferase (ALT) levels, which are common and often unexplained.

METHODS

Participants from the longitudinal observational AIDS Clinical Trials Group HAILO cohort without a history of hepatitis C virus (HCV) or hepatitis B virus (HBV) infection nor reported heavy alcohol use were included. Clinical and demographic characteristics, including medication use, the hepatic steatosis index (HSI), and metabolic syndrome (MetS) were compared between participants with and without ALT elevation.

RESULTS

Six hundred sixty-two participants were included; 444 (67%) had ≥1 and 229 (35%) ≥2 consecutive ALT elevations during a median of 4.0 years of follow-up. HSI and Hispanic or other (non-White or Black) race/ethnicity were consistently associated with higher odds of abnormal ALT (odds ratio [OR] 1.1 for HSI as a continuous variable, OR 1.9-2.8 for Hispanic/other race/ethnicity for ≥1 or ≥2 ALT elevations); older age and current smoking were associated with lower odds of abnormal ALT. Associations with metabolic disease, as well as with incident HBV and HCV infection, were strengthened by restricting outcomes to persistent and higher degrees of ALT elevation.

CONCLUSIONS

ALT elevation was common in this cohort of PWH and associated with metabolic disease and hepatic steatosis markers. Nonalcoholic fatty liver disease is likely a common cause of liver inflammation in PWH receiving suppressive antiretrovirals, deserving targeted diagnosis and intervention.

Controlled attenuation parameter accurately detects liver steatosis in people with HIV

OBJECTIVES

Hepatic steatosis is a leading cause of cirrhosis and hepatocellular carcinoma and is highly prevalent in persons with HIV (PWH). However, most studies of hepatic steatosis diagnosis in PWH have focused on those at high risk. We determined the accuracy of vibration-controlled transient elastography (VCTE) with controlled attenuation parameter (CAP) in detecting mild or greater hepatic steatosis as compared with the noninvasive gold standard magnetic resonance spectroscopy (MRS) in PWH.

METHODS

Among 149 participants with and without HIV, we evaluated test characteristics of CAP and calculated serum indices Hepatic Steatosis Index (HSI) and STEATO-ELSA in identifying 3T MRS-measured hepatic steatosis (defined as a liver fat fraction ≥5%).

RESULTS

Most participants were women and over half were African American. Median BMI was 27 kg/m 2 . Hepatic steatosis prevalence by MRS and CAP (cutoff 248 dB/m) was 36% and 47%, respectively. CAP had an AUROC of 0.82, and the at least 248 dB/m cutoff yielded a sensitivity, specificity, positive-predictive value, and negative-predictive value of 83%, 72%, 61%, and 88%, respectively. These test characteristics were not statistically different from the optimal cutoff of at least 252 dB/m. Higher waist circumference, greater visceral adipose tissue, heavy alcohol use, and VCTE scans flagged as having the probe positioned too low were associated with CAP and MRS discordance. Serum indices of hepatic steatosis had slightly worse performance characteristics than CAP.

CONCLUSION

CAP may be an effective alternative to MRS for noninvasive hepatic steatosis assessment in PWH. The commonly used CAP cutoff of at least 248 dB/m to diagnose hepatic steatosis can be used in PWH.

Prevalence and risk factors of nonalcoholic steatohepatitis with significant fibrosis in people with HIV

OBJECTIVE

Metabolic risk factors and nonalcoholic fatty liver disease (NAFLD) in people with HIV (PWH) have been increasing. Patients exhibiting the inflammatory subtype nonalcoholic steatohepatitis (NASH) are at increased risk of liver-related complications. Therefore, the aim was to investigate the prevalence of NASH with significant fibrosis in PWH using noninvasive tests (NITs).

DESIGN

In this prospectively enrolling cohort study, 282 PWH were explored for hepatic steatosis, fibrosis and steatohepatitis using vibration-controlled transient elastography (VCTE) and the Fibroscan-AST (FAST) score.

METHODS

On the basis of controlled attenuation parameter (CAP; dB/m) and liver stiffness measurement (LSM; kPa), patients were categorized according to the presence of steatosis (≥275 dB/m) and significant fibrosis (≥8.2 kPa). The FAST score was calculated according to established cut-offs.

RESULTS

The prevalence of hepatic steatosis in this cohort was 35.5% ( n  = 100) with 75 (75%) of these patients fulfilling the criteria of NAFLD. The prevalence of significant fibrosis (≥ F2) was 6.7% ( n  = 19). The FAST score identified a total of 32 (12.3%) patients with a cut-off greater than 0.35, of whom 28 (87.5%) PWH qualified as NASH. On multivariable analysis, waist circumference was a predictor of hepatic steatosis and type 2 diabetes was a predictor of significant fibrosis. Type 2 diabetes and ALT remained independent predictors of a FAST score greater than 0.35.

CONCLUSION

NASH with significant fibrosis is highly prevalent among PWH. The FAST score may be helpful to identify patients at risk for significant liver disease.

A pilot study of microbial signatures of liver disease in those with HIV mono-infection in Rio de Janeiro, Brazil

OBJECTIVE

The rectal microbiome was examined to assess the relationship between the microbiome and liver disease in HIV-infection.

DESIGN

Eighty-two HIV-1 mono-infected individuals from the PROSPEC-HIV-study (NCT02542020) were grouped into three liver health categories based on results of controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) of transient elastography: normal (n = 30), steatosis (n = 30), or fibrosis (n = 22).

METHODS

Liver steatosis and fibrosis were defined by CAP at least 248 dB/m and LSM at least 8.0 kPa, respectively. 16S rRNA gene and whole genome shotgun metagenomic sequencing were performed on rectal swabs. Bacterial differences were assessed using zero-inflated negative binomial regression and random forests modeling; taxonomic drivers of functional shifts were identified using FishTaco.

RESULTS

Liver health status explained four percentage of the overall variation (r2 = 0.04, P = 0.003) in bacterial composition. Participants with steatosis had depletions of Akkermansia muciniphila and Bacteroides dorei and enrichment of Prevotella copri, Finegoldia magna, and Ruminococcus bromii. Participants with fibrosis had depletions of Bacteroides stercoris and Parabacteroides distasonis and enrichment of Sneathia sanguinegens. In steatosis, functional analysis revealed increases in primary and secondary bile acid synthesis encoded by increased Eubacterium rectale, F. magna, and Faecalibacterium prausnitzii and decreased A. muciniphila, Bacteroides fragilis and B. dorei. Decreased folate biosynthesis was driven by similar changes in microbial composition.

CONCLUSION

HIV mono-infection with steatosis or fibrosis had distinct microbial profiles. Some taxa are similar to those associated with non-alcoholic fatty liver disease in HIV-negative populations. Further studies are needed to define the role of the gut microbiota in the pathogenesis of liver disease in HIV-infected persons.