Hepatic steatosis and HIV infection

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.

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.

Associations of visceral fat thickness and anthropometric measurements with non-alcoholic fatty liver disease development in male patients mono-infected with human immunodeficiency virus

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) represents the most common form of chronic liver disease in mono-infected (without concomitant hepatitis B and/or C virus infection) people living with human immunodeficiency virus (HIV). The proper and on time identification of at-risk HIV-positive individuals would be relevant in order to reduce the rate of progression from NAFLD into non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma.

OBJECTIVES

The aim of this study was to explore visceral fat thickness (VFT) and anthropometric measurements associated with the development of NAFLD in patients mono-infected with HIV and on long-standing combination antiretroviral therapy (cART).

METHOD

Eighty-eight (n = 88) HIV-positive male patients, average age 39.94 ± 9.91 years, and stable on cART, were included in this prospective study. VFT was measured using ultrasonography. Anthropometric measurements included body mass index (BMI), waist-to-hip ratio (W/H), waist-to-height ratio (WHtR), waist and hip circumference (WC, HC). Differences between variables were determined using the chi-square test. The receiver operating characteristic (ROC) curve and the Youden index were used to determine optimal cut-off values of VFT and hepatic steatosis. The area under the curve (AUC), 95% confidence intervals, sensitivity and specificity are reported for the complete sample. Significance was set at p < 0.05.

RESULTS

Patients with steatosis had significantly higher values of BMI, HC, WC, W/H and WHtR. The VFT was higher in patients with steatosis (p < 0.001). Specifically, VFT values above 31.98 mm and age > 38.5 years correlated with steatosis in HIV-positive patients, namely sensitivity 89%, specificity 72%, AUC 0.84 (95% CI, 0.76-0.93, p < 0.001), with the highest Youden index = 0.61. The sensitivity of the age determinant above this cut-off point was 84%, specificity 73% and AUC 0.83 (95% CI, 0.75-0.92, p < 0.001), with the highest Youden index of 0.57.

CONCLUSION

In the absence of more advanced radiographic and histological tools, simple anthropometric measurements and VFT could assist in the early identification of persons at risk of hepatic steatosis in low- and middle-income regions.

Resveratrol increases CD68⁺ Kupffer cells colocalized with adipose differentiation-related protein and ameliorates high-fat-diet-induced fatty liver in mice

SCOPE

Resveratrol reportedly improves fatty liver. This study purposed to elucidate the effect of resveratrol on fatty liver in mice fed a high-fat (HF) diet, and to investigate the role of liver macrophages (Kupffer cells).

METHODS AND RESULTS

C57BL/6 mice were divided into three groups, receiving either a control diet, HF diet (50% fat), or HF supplemented with 0.2% resveratrol (HF + res) diet, for 8 weeks. Compared with the HF group, the HF + res group exhibited markedly attenuated fatty liver, and reduced lipid droplets (LDs) in hepatocytes. Proteomic analysis demonstrated that the most downregulated protein in the livers of the HF + res group was adipose differentiation-related protein (ADFP), which is a major constituent of LDs and reflects lipid accumulation in cells. The HF + res group exhibited greatly increased numbers of CD68(+) Kupffer cells with phagocytic activity. Immunohistochemistry showed that several CD68(+) Kupffer cells were colocalized with ADFP immunoreaction in the HF + res group. Additionally, the HF + res group demonstrated markedly decreased TNF-alpha production, which confirmed by both liver mononuclear cells stimulated by LPS in vitro and in situ hybridization analysis, compared with the HF group.

CONCLUSION

Resveratrol ameliorated fatty liver and increased CD68-positive Kupffer cells with downregulating ADFP expression.

[Lipodystrophy and echographic hepatic steatosis in HIV-positive patients under highly active antiretroviral therapy (HAART) in Yaounde (Cameroon)]

The association between sonographic liver steatosis and clinical lipodystrophy in AIDS patients treated by highly active antiretroviral therapy (HAART) has been studied. We conducted a cross-sectional study reviewing medical files of 117 AIDS patients followed up in Yaounde, Cameroon (6.3 F/1 M, mean age = 40 ± 9.4 years), and treated the patients with HAART protocol comprising stavudine or zidovudine for at least six months. All participants underwent abdominal ultrasonography and anthropometric assessment including body mass index (BMI). Data analysis included determining the association between sonographic liver steatosis, clinical lipodystrophy, and other clinical and biological data using the ¢(2) test, and the calculation of odd ratio. Fifty-one patients presented clinical lipodystrophy. The sonographic prevalence of hepatomegaly and splenomegaly was 70.1% and 25.6%, respectively. The overall prevalence of sonographic steatosis was 28.2%; specifically 37.3% among lipodystrophic patients and 21.1% among nonlipodystrophic patients (P = 0.03). According to the type of lipodystrophy, the prevalence was 40.6% among lipohypertrophic patients, 38.5% among lipodystrophic patients, and 16.7% among lipoatrophic patients. Clinical lipohypertrophy was statistically associated with a higher prevalence of sonographic steatosis (odd ratio = 2.5; 95% CI: [1.01-6.39], and P = 0.04). HAART protocol including stavudine was associated with lipodystrophy. The prevalence of sonographic liver steatosis is high among AIDS patients under HAART and is associated with lipohypertrophy.

The effect of HIV infection, immunodeficiency, and antiretroviral therapy on the risk of hepatic dysfunction

BACKGROUND

Limited data exists regarding the effect of chronic HIV infection on the liver. We sought to characterize the hepatic risks of HIV infection, immunodeficiency, and cumulative use of antiretroviral therapy (ART).

METHODS

Adult HIV infected and 10:1 age-matched and sex-matched HIV-uninfected individuals were followed for incident hepatic dysfunction or hepatic dysfunction-related death. Multivariable Poisson regression models were used to obtain incident rate ratios, adjusting for multiple hepatic risk factors including alcohol/drug abuse, hepatitis B and C, and diabetes.

RESULTS

We identified 20,775 HIV-infected and 215,158 HIV-uninfected individuals. HIV-infected individuals had a significantly greater overall risk compared with HIV-uninfected individuals of both hepatic dysfunction and hepatic dysfunction-related death. The highest risk was seen in patients with low CD4 cell counts not on ART [adjusted rate ratio of hepatic dysfunction-related death 59.4; (95% confidence interval: 39.3 to 89.7), P < 0.001; hepatic dysfunction, adjusted rate ratio 15.7 (95% confidence interval: 11.4 to 21.6), P < 0.001]. In an HIV-infected only model, factors that increased risk included low CD4 cell count, high HIV RNA level, alcohol/drug abuse, hepatitis B or C coinfection, and diabetes. Longer cumulative exposure to ART did not increase risk, regardless of therapy class.

CONCLUSIONS

HIV-infected individuals have a higher risk of hepatic dysfunction and hepatic dysfunction-related death compared with HIV-uninfected individuals, even with adjustment for known hepatic risk factors. Hepatic outcomes were associated with lower CD4+ T-cell counts but not with longer cumulative ART exposure. These findings provide indirect evidence supporting early use of ART to reduce the risk for hepatic-related complications.

Human immunodeficiency virus is the major determinant of steatosis and hepatitis C virus of insulin resistance in virus-associated fatty liver disease

BACKGROUND AND AIMS

To promote our understanding of the relative contribution of metabolic and viral factors, the independent predictors of fatty liver and insulin resistance (IR) were assessed by comparing patients with nonalcoholic fatty liver disease (NAFLD) to individuals with virus-associated fatty liver disease (VAFLD): human immunodeficiency virus (HIV)-VAFLD, hepatitis C virus (HCV)-VAFLD and HIV-HCV-VAFLD.

METHODS

One hundred eighty eight consecutive patients with viral infections (103 HIV, 85 patients with HCV genotype 1 infection: 45 mono-infected and 40 HIV/HCV co-infected) with or without steatosis and 126 NAFLD patients were analyzed. Steatosis was diagnosed by ultrasonography. To assess the odds ratio (OR) of steatosis and IR, HCV and NAFLD, respectively, were used as the reference values. IR was evaluated through homeostasis model (HOMA) and the metabolic syndrome (MetS) using standard criteria.

RESULTS

The prevalence of VAFLD was 47%. Multivariate logistic regression analysis was carried out using HCV as the reference. VAFLD was predicted by HIV, HIV/HCV, female gender, waist circumference (WC) and HOMA (OR = 3.99, 3.76, 2.80, 1.08 and 1.18). According to multiple linear regression using NAFLD as the reference, IR was predicted by HCV, HIV and HIV/HCV, WC, triglycerides (coefficient beta = 2.25, 0.99, 1.86, 0.08, 0.05, respectively). In linear models, for any given number of components of MetS, HCV and HCV/HIV-associated fatty liver disease had greater HOMA compared to NAFLD (p <0.001).

CONCLUSIONS

Whereas HIV confers a higher risk of steatosis, VAFLD is associated with higher IR than NAFLD and such an effect is specifically linked to HCV rather than to HIV infection.

Sex hormones, insulin resistance, and diabetes mellitus among men with or at risk for HIV infection

OBJECTIVE

To examine the relationship of free testosterone (FT) and sex hormone-binding globulin (SHBG) with insulin resistance and diabetes mellitus (DM) in HIV disease.

DESIGN

Cross-sectional analysis from 322 HIV-uninfected and 534 HIV-infected men in the Multicenter AIDS Cohort Study.

METHODS

: The main outcomes were DM and homeostasis model assessment-insulin resistance (HOMA-IR). DM was defined as fasting serum glucose ≥126 or self-reported DM and use of DM medications. HOMA-IR was calculated from fasting serum glucose and fasting insulin.

RESULTS

Compared with HIV-uninfected men in our sample, HIV-infected men were younger, with lower body mass index, and more often black. HIV-infected men had lower FT (P < 0.001) and higher SHBG (P < 0.0001). The adjusted odds ratio for DM was 1.98 (95% confidence interval: 1.04 to 3.78); mean adjusted log HOMA-IR was 0.21 units higher in HIV-infected men (P < 0.0001). Log SHBG, but not log FT, was associated with DM (odds ratio = 0.44, 95% confidence interval: 0.25 to 0.80) in both groups. Log FT and log SHBG were inversely related to insulin resistance (P < 0.05 for both) independent of HIV.

CONCLUSIONS

Compared with HIV-uninfected men, HIV-infected men had lower FT, higher SHBG, and more insulin resistance and DM. Lower FT and lower SHBG were associated with insulin resistance regardless of HIV serostatus. This suggests that sex hormones play a role in the pathogenesis of glucose abnormalities among HIV-infected men.

Hepatic steatosis in patients coinfected with human immunodeficiency virus/hepatitis C virus: a meta-analysis of the risk factors

Hepatic steatosis (HS) is frequent in patients with hepatitis C virus (HCV) infection, occurring in 40%-80%, associating with metabolic and virus-related factors, namely, genotype 3 and viral load. Human immunodeficiency virus (HIV) infection and antiretroviral treatment seem to be risk factors for HS. Several studies addressed this issue in coinfected patients, with discrepant results. A meta-analysis was performed on the HS risk factors in coinfected patients. Eligible studies were identified through structured keywords including coinfection, HCV, HIV, and steatosis in relevant databases including PubMed. Pooled odds ratios (ORs) and confidence limits (CIs) were obtained with the random-effects model and the DerSimonian-Laird method. Twelve studies, including 1,989 coinfected patients, were selected. Twenty percent were infected with HCV genotype 3. The overall prevalence of HS was 50.8% (23%-72%). Four studies also included 1,540 HCV monoinfected patients, not showing an increased risk for HS in coinfected patients (OR 1.61, 95% CI 0.84-3.10, P = 0.151). In coinfected patients, HS was associated with higher body mass index (OR 1.13, 95% CI 1.07-1.19, P < 0.001), diabetes mellitus (OR 2.32, 95% CI 1.32-4.07, P = 0.003), elevated alanine aminotransferase levels (OR 1.28, 95% CI 1.02-1.61, P = 0.035), necroinflammatory activity (OR 1.72, 95% CI 1.11-2.67, P = 0.016), and fibrosis (OR 1.67, 95% CI 1.20-2.34, P = 0.003). No associations were found between HS and gender, other metabolic factors (dyslipidemia, glucose, metabolic syndrome), HCV-related factors (genotype, viral load), or HIV-related factors (viral load, CD4 count, antiretroviral therapy, and class of medication).

CONCLUSION

In coinfected patients, HS does not seem to be more frequent than in HCV monoinfected patients and is mostly associated with metabolic factors, such as increased weight, diabetes mellitus, and more severe liver disease. The fact that no associations with HCV factors were found may be due to the small percentage of genotype 3-infected patients.

MR spectroscopy of the liver: principles and clinical applications

Magnetic resonance (MR) spectroscopy allows the demonstration of relative tissue metabolite concentrations along a two- or three-dimensional spectrum based on the chemical shift phenomenon. An MR spectrum is a plot of the signal intensity and frequency of a chemical or metabolite within a given voxel. At proton MR spectroscopy, the frequency at which a chemical or compound occurs depends on the configuration of the protons within the structure of that chemical. At in vivo proton MR spectroscopy, the frequency location of water is used as the standard of reference to identify a chemical. The frequency shift or location of chemicals relative to that of water allows generation of qualitative and quantitative information about the chemicals that occur within tissues, forming the basis of tissue characterization by MR spectroscopy. MR spectroscopy also may be used to quantify liver fat by measuring lipid peaks and to diagnose malignancy, usually by measuring the choline peak. Interpretation of MR spectroscopic data requires specialized postprocessing software and is subject to technical limitations including low signal-to-noise ratio, masking of metabolite peaks by dominant water and lipid peaks, partial-volume averaging from other tissue within the voxel, and phase and frequency shifts from motion. MR spectroscopy of the liver is an evolving technology with potential for improving the diagnostic accuracy of tissue characterization when spectra are interpreted in conjunction with MR images.

A translational view of the genetics of lipodystrophy and ectopic fat deposition

A wide range of lipodystrophy syndromes exist, each with varying clinical presentations, and yet cumulatively they underscore the importance of adipocyte biology in human metabolism. Loss of the ability to retain excess lipids in "classical" adipose tissue stores can lead to the overdevelopment of ectopic fat stores, often creating severe perturbations of both glucose and lipid homeostasis. Linkage analysis and candidate sequencing efforts have successfully identified responsible mutations for multiple forms of lipodystrophy. Recently, the reduction in the cost of DNA sequencing has resulted in discovery of many novel mutations within both known and novel loci. In this review, we present the steps involved in clinical characterization of a suspected lipodystrophy case, an overview of the clinical manifestations, molecular findings, and pathogenic basis of different forms of lipodystrophy, a discussion of therapeutic options for lipodystrophy patients, and an examination of genetic advances that will be used to identify additional pathogenic mechanisms.

Evaluation of quantitative liver function tests in HIV-positive patients under anti-retroviral therapy

Background and aims

Quantitative tests of liver function (QTLF) which are based on the hepatic metabolism or clearance of test substances have been successfully used to predict prognosis of a variety of different liver diseases. Still sufficient data in HIV-patients under anti-retroviral therapy (ART) are lacking. Therefore, the aim of this prospective study was to investigate if and to what extent ART influences a broad panel of quantitative tests of liver function in patients with HIV-infection.

Patients and methods

Nineteen patients (14 males, 5 females, mean age 40 years) with HIV-infection underwent QTLF including lidocaine half-life test (LHT), galactose elimination capacity (GEC), and indocyanine green clearance (IGC). These tests were performed before and 3 to 6 months after initiation of anti-retroviral therapy. Twenty age-matched healthy, medication-and virus-free adults served as controls.

Results

Lidocaine half-life was significantly lower in HIV-patients without ART. Combining anti-retroviral therapies shifted cytochrome p450 activity back into standard ranges. Galactose elimination capacity as a parameter of cytosolic liver function and indocyanine green clearance as a parameter of liver perfusion were not affected by ART.

Conclusions

QTLF may be a tool to predict prognosis or hepatic complications in HIV-infected patients with liver disease. Early determination of lidocaine half-life seems to be useful - this should be considered during the treatment of HIV-positive individuals.

[Non alcoholic steatosis in HIV infection]

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatosis (NASH) are common conditions in the setting of HIV infection, especially if HCV coinfection or metabolic syndrome's features are present. The factors that contribute to the progression of NAFLD to NASH and fibrosis are not completely known and the role of antiretroviral therapy is especially controversial. Although the natural history of NASH in the setting of HIV infection is unknown, it may emerge as one of the leading causes of liver disease over the long term in these patients. Liver biopsy is still the gold standard for the diagnosis of NASH. Indeed, although non-invasive techniques are promising tools for the diagnosis of NAFLD, they do not assess liver damage. There is no specific therapy for NASH in HIV infection, as the role of glitazones has not been evaluated in these patients.

Fatty liver and hyperlipidemia in a cohort of HIV-positive Africans on highly active antiretroviral therapy

AIM

To determine the prevalence of fatty liver and to assess its association with hyperlipidemia and other metabolic risk factors in HIV/AIDS patients on long-term antiretroviral therapy.

METHODS

A prospective cross-sectional study of 113 adults attending an urban outpatient HIV clinic in Lagos, Nigeria. Demographic characteristics were obtained using interviewer administered questionnaires, and serum levels of fasting glucose, total cholesterol, high-density lipoprotein (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and alanine transaminase were determined. Ultrasound scan imaging was used to identify hepatic steatosis.

RESULTS

One hundred thirteen subjects, mean age (SD), 38.7 (9.9) years on highly active antiretroviral therapy (HAART) therapy for 6 to 42 months were evaluated. Sixty-six (58.4%) were female and 47 (41.6) were male. Fifteen (13.3%) had hepatic steatosis. Total cholesterol > 200 mg/dL, LDL-C > 130 mg/dL, and fasting serum triglycerides > 150 mg/dL were seen in 28%, 24% and 35%, respectively. The presence of fatty liver was significantly associated with hepatomegaly (p = .03) and elevated LDL-C (p = .01).

CONCLUSION

The prevalence of hepatic steatosis is lower than reported in Caucasian populations, but strongly associated with hepatomegaly and hyperlipidemia in subjects on long-term HAART. Early recognition of fatty liver and regular screening for lipid are warranted in Africans receiving long-term HAART.

Evaluation of diffuse liver steatosis by ultrasound, computed tomography, and magnetic resonance imaging: which modality is best?

PURPOSE

To compare ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) determination of diffuse liver steatosis.

MATERIALS AND METHODS

Quantification of liver steatosis on ultrasound, CT, and MRI was correlated with histopathology in 67 patients.

RESULTS

Opposed-phase MRI demonstrated the highest correlation with steatosis (0.68 and 0.69, P<.01; intraclass correlation coefficient, 0.93). Spearman's correlation (and intraclass correlation) coefficients were lowest for ultrasound [0.54, 0.33 (0.40)] and enhanced CT [0.33, 0.39 (0.97)].

CONCLUSION

Opposed-phase MRI demonstrated best overall performance for determining steatosis.

HIV-related liver disease: ARV drugs, coinfection, and other risk factors

Highly-active antiretroviral therapy (HAART) has proven remarkably effective for prolonging the life of patients with human immunodeficiency virus (HIV). However, while most HAART agents are safe, many have the potential to cause liver toxicity. Physicians must therefore consider the possibility of drug-induced liver injury in the management of HIV-infected patients, especially those with certain risk factors such as coinfection with hepatitis B virus (HBV) or hepatitis C virus (HCV), female gender, alcohol abuse, older age, or obesity. Understanding how, when, and why drug-related liver damage occurs is key to managing these patients safely and effectively. Knowledge of HAART-related liver effects will help ensure that patients receive the most benefit with the least toxicity from any given drug regimen. As more information about the mechanisms of drug related liver injury is known, clinicians will be better able to tailor therapies to suit individual situations, resulting in greater patient safety and outcomes.

Hepatic histopathology and clinical characteristics associated with antiretroviral therapy in HIV patients without viral hepatitis

BACKGROUND

All available ARV (antiretroviral) agents can cause hepatotoxicity. Many case reports of ARV-induced hepatotoxicity have been described in patients with confounding viral hepatitis. This case series is comprised 23 HIV-positive patients with hepatic enzyme abnormalities but without the evidence of viral hepatitis. The data available for these 23 patients were assessed with an effort to establish any correlation between ARV therapy and abnormal liver function tests (LFTs) as well as the histologic findings on liver biopsies.

METHODS

The 23 participants included in this study were referred to a hepatology/gastrointestinal clinic that catered specifically to HIV patients. The patients were referred by their HIV providers for evaluation of elevated LFTs, gastrointestinal symptoms or cirrhosis. The data surveyed included variables associated with hepatotoxicity and HIV infection.

RESULTS

Liver biopsies were obtained in 21 out of 23 participants. The remaining two participants had evidence of cirrhosis based on imaging studies. The LFT elevations were definitely or possibly attributed to ARV therapy in 17 out of 23 participants. Specifically, the biochemical hepatotoxicity was definitely related to ARV therapy in six and possibly related to ARV medications in 11 participants. Nine out of 17 participants had evidence of nonalcoholic steatohepatitis, whereas four out of 17 had clinical features of lipodystrophy. Six participants had elevated LFTs before starting ARV therapy. The participants with nonalcoholic fatty liver diseases had normal LFTs for many years after which a steep rise was noted. All participants with nonalcoholic fatty liver diseases were exposed to nucleoside reverse transcriptase inhibitors.

CONCLUSION

ARV medications, particularly the nucleoside reverse transcriptase inhibitors, can cause a dose-dependent hepatotoxicity that occurs after several months of exposure and possibly result in increasing the adverse effects of alcohol and obesity. Owing to the overlap of ARV medications, the contribution of each class of drugs toward the observed hepatotoxicity is not entirely clear. Liver biopsies should be considered in patients receiving ARV therapy with elevated LFTs and/or evidence of fatty liver.

Relationship between leptin expression and hepatic steatosis in liver tissues of patients with acquired immunodeficiency syndrome

AIM: To investigate the prevalence of hepatic steatosis and its correlation with the expression of leptin in patients with acquired immunodeficiency syndrome (AIDS) in Beijing district.

METHODS: A total of 18 Chinese AIDS patients were included in this study. Immunohistochemistry was used to detect the expression of leptin, CD68 and tumor necrosis factor-α (TNF-α) in liver specimens of these patients. The hepatic steatosis and histopathological changes of these liver specimens were evaluated. Meanwhile, we also analyzed the relations of age, gender, body mass index (BMI), liver function, fasting blood glucose, cholesterol, triglyceride, HIV load, CD4⁺ count and CD8⁺ count with hepatic steatosis.

RESULTS: In this group of AIDS patients with AIDS, the prevalence of hepatic steatosis was 61.1% (11/18). Macrovesicular steatosis was 72.7% (8/11). The patients complicated with liver disease-associated opportunistic infections accounted for 22.2% (4/18). The positive rate of leptin was 44.4% in AIDS patients, and the positive rates of leptin and CD68 in steatosis patients were higher than those in non-steatosis patients without statistical significances. The positive expression of TNF-α in AIDS patients with steatosis was significantly higher than those in patients without steatosis (100% vs 42.9%, P = 0.012), but the CD8⁺ cell count (× 10⁶ cells/L) was just the opposite (142.0 ± 93.0 vs 515.6 ± 320.7, P = 0.026). Hepatic steatosis had no correlations with the patients' age, gender, BMI, liver function, blood-fasting sugar, cholesterol, triglyceride, HIV load, CD4⁺ count and coinfection of hepatitis C virus.

CONCLUSION: Hepatic steatosis is highly prevalent in AIDS patients and shows no significant relations with leptin expression, which seems to associate with the mechanism of injury-repair in liver.

Alterations in hepatic metabolism in fld mice reveal a role for lipin 1 in regulating VLDL-triacylglyceride secretion

OBJECTIVE

Lipin 1 controls fatty acid metabolism in the nucleus as a transcriptional regulator and in the cytosol as an enzyme catalyzing the penultimate step in phosphoglycerol triacylglyceride (TAG) synthesis. We sought to evaluate the effects of lipin 1 on hepatic TAG synthesis and secretion by gain-of-function and loss-of-function approaches.

METHODS AND RESULTS

Rates of TAG synthesis were not impaired in hepatocytes isolated from adult lipin 1-deficient (fld) mice and were actually increased in 14-day-old fld mice. Additionally, compared to littermate controls, VLDL-TAG secretion rates were markedly increased in fld mice of both ages. Lipin 1 overexpression did not alter TAG synthesis rates but significantly suppressed VLDL-TAG secretion. The lipin 1-mediated suppression of VLDL-TAG secretion was linked to the peptide motif mediating its transcriptional-regulatory effects. However, the expression of candidate genes required for VLDL assembly and secretion was unaltered by lipin 1 activation or deficiency. Finally, the hepatic expression of lipin 1 was diminished in obese insulin-resistant mice, whereas adenoviral-mediated overexpression of lipin 1 in liver of these mice inhibits VLDL-TAG secretion and improves hepatic insulin signaling.

CONCLUSIONS

Collectively, these studies reveal new and unexpected effects of lipin 1 on hepatic TAG metabolism and obesity-related hepatic insulin resistance.

Effect of antiretroviral therapy and hepatitis c co-infection on changes in lipid levels in HIV-Infected patients 48 weeks after initiation of therapy

Hepatitis C virus (HCV) commonly co-infects HIV-infected individuals. Antiretroviral therapy (ART) is associated with elevated serum lipid levels, and HCV infection is associated with low serum lipid levels. Fasting lipid levels were investigated in 1,434 ART-naïve HIV-infected people participating in the AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) protocol who prospectively initiated ART with 3 agents. Subjects with elevated liver-associated enzymes (>5 x ULN) were excluded. Demographics, body mass index, HCV status, CD4 cell count, HIV RNA, liver enzymes, lipid levels, and glucose were assessed before and following 48 weeks of ART. HCV-positive subjects (n = 160; 11%) were older, more likely to be Black, have a history of intravenous drug use (IDU), have higher baseline liver-associated enzyme levels than the HCV-negative group (p < .001 for each), and to have diabetes at baseline (5% vs. 2%, p = .07). Lipid levels rose in both groups following ART, and the differences were not significant except that HDL levels increased significantly more in the HCV-positive group (p = .006). In summary, HCV infection did not appear to provide significant protection against ART-induced hyperlipidemia in this cohort of HIV-infected subjects prospectively enrolled in ART trials, although HDL levels rose to a greater degree.

Relation of epicardial fat and alanine aminotransferase in subjects with increased visceral fat

BACKGROUND

Increased visceral adipose tissue (VAT) is a risk factor for an unfavorable cardio-metabolic profile and fatty liver. Individuals with human immunodeficiency virus (HIV) on highly active antiretroviral therapy (HAART) can be associated with metabolic syndrome (MS) and higher visceral fat. However, the potential link between cardiac adiposity, emerging index of visceral adiposity, and fatty liver is still unexplored.

OBJECTIVE

To evaluate whether echocardiographic epicardial adipose tissue, index of cardiac adiposity, could be related to serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity, surrogate markers of fatty liver, in HIV-infected patients with (HIV+MS+) and without HAART-associated MS (HIV+MS-).

METHODS AND PROCEDURES

This was a cross-sectional observational study on 57 HIV+MS+ patients, 52 HIV+MS- and 57 HIV-negative subjects with MS (HIV-MS+), as control group. Epicardial fat thickness and intra-abdominal VAT were obtained by echocardiography and magnetic resonance imaging (MRI), respectively. Serum ALT and AST activity, plasma adiponectin levels, and MS biochemical parameters were measured.

RESULTS

Echocardiographic epicardial fat thickness was correlated with MRI-VAT (r = 0.83, P < 0.01), AST/ALT ratio (r = 0.77, P < 0.01), ALT (r = 0.58, P < 0.01), AST (r = 0.56, P < 0.01), and adiponectin (r = -0.45, P < 0.01) in HIV+MS+. MRI-VAT and AST/ALT ratio were the best correlates of epicardial fat thickness (r (2) = 0.45, P < 0.01).

DISCUSSION

This study shows for the first time a clear relationship of epicardial fat, index of cardiac and visceral adiposity, and serum ALT and AST activity, markers of fatty liver, in subjects with increased visceral adiposity and cardio-metabolic risk. This correlation seems to be independent of overall adiposity and rather function of excess visceral adiposity.

Hepatic steatosis in HIV-HCV coinfected patients in France: comparison with HCV monoinfected patients matched for body mass index and HCV genotype

BACKGROUND

Significance of steatosis in HIV-HCV coinfection remains controversial.

AIM

To compare the prevalence and predictors of hepatic steatosis between HIV-HCV and HCV patients matched for steatosis known determinants.

METHODS

A total of 564 HCV-naive patients undergoing liver biopsy were studied: 137 with HIV-HCV coinfection and 427 with HCV monoinfection, among whom 137 were matched for age, gender, body mass index and HCV genotype.

RESULTS

Steatosis of any grade (67.1% vs. 41.6%, P < 0.0001), mixed steatosis (55.4% vs. 21.1%, P < 0.0001), severe histological activity (A2-A3: 78.1% vs. 55.5%, P < 0.0001) and severe fibrosis (F3-F4: 33.1% vs. 15.3%, P < 0.0001) were significantly more common in coinfected than in matched monoinfected patients. In multivariate analysis, steatosis was associated only with severe histological activity [odds ratio (OR): 3.1 (95% CI: 1.3-7.1)] in coinfected patients and with elevated body mass index [OR; 1.3 (1.1-1.5)], HCV genotype 3 [OR: 5.6 (2.3-13.9)], severe histological activity [OR: 3.1 (1.3-7.3)] and severe fibrosis [OR: 4.7 (1.3-17.3)] in monoinfected patients.

CONCLUSIONS

Steatosis is significantly more common and severe in HIV-HCV coinfected than in HCV monoinfected French patients, even after matching for body mass index and HCV genotype. Steatosis is associated only with severe histological activity in coinfected patients and with previously reported factors in monoinfected patients, thus suggesting different underlying mechanisms.

HIV-associated adipose redistribution syndrome (HARS): definition, epidemiology and clinical impact

A segment of the HIV infected population develops abnormal and excessive accumulation of adipose tissue in the trunk, including accumulation of visceral (deep abdominal) adipose tissue. This condition, known as HIV-related adipose redistribution syndrome (HARS), may also be accompanied by fat accumulation in the upper back/neck (dorsocervical region) and/or depletion of subcutaneous adipose tissue from the abdomen, face, limbs, or buttocks. HARS is estimated to occur in up to 32% of patients and is associated with health risks similar to those of metabolic syndrome. Techniques to detect and measure HARS include physician and patient assessments and radiologic or anthropometric methods.

Hepatitis C infection is associated with lower lipids and high-sensitivity C-reactive protein in HIV-infected men

Increased cardiovascular risk has been linked to HIV infection and combination antiretroviral therapy, but the impact of hepatitis C virus (HCV) status on indices of cardiovascular risk has not been routinely assessed in the HIV-infected population. The objective of this study was to analyze associations of HCV, HIV, and combination antiretroviral therapy with lipid levels and C-reactive protein (CRP) among older men. We measured fasting total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride, and high-sensitivity CRP serum levels in a cross-sectional study of 108 HIV-infected and 74 HIV-uninfected at-risk older men. One hundred ten men (60%) had detectable HCV RNA, with no difference by HIV status (p = 0.25). The majority (88%) of men with HCV infection had a history of injection drug use. Among all men, HCV infection was independently associated with lower total cholesterol (p < 0.001), LDL-C (p < 0.001), triglycerides (p = 0.01), and CRP (p = 0.001). Among HIV-infected men, HCV infection was associated with lower total cholesterol (p < 0.001), LDL-C (p < 0.001), and CRP (p = 0.004). HCV infection was associated with lower triglycerides among men on protease inhibitors (PI) (p = 0.02) and non-PI combination antiretroviral therapy (p = 0.02), but not among antiretroviral-naïve men. These findings demonstrate an association of lower serum lipid and CRP levels with HCV infection and suggest that HCV status should be assessed as an important correlate of cardiovascular risk factors in studies of older men with or at risk for HIV.

Prevalence of and Factors Associated With Hepatic Steatosis in Patients Coinfected With Hepatitis C Virus and HIV

BACKGROUND

Hepatic steatosis is a common feature in liver biopsies from patients with chronic hepatitis C and is associated with fibrosis progression. Patients with HIV infection and hepatitis C virus (HCV) coinfection have more rapid progression of liver fibrosis than patients with HCV infection alone. The prevalence and factors associated with hepatic steatosis are not well defined in HCV-HIV-coinfected patients.

METHODS

Steatosis was assessed among 148 HCV-HIV-coinfected patients of the Aquitaine Cohort. Steatosis was graded as follows: none, mild (1%-10% of hepatocytes), moderate (11%-30%), severe (31%-60%), and massive (more than 60%). Epidemiologic, clinical, biologic, and therapeutic data were retrieved from the cohort database to investigate the risk factors.

RESULTS

Steatosis was present in 67% of patients (95% confidence interval [CI]: 59% to 74%) and was at least moderate in 30% (95% CI: 23% to 38%). Steatosis was macrovesicular or mixed (macro- and microvesicular) in 40.5% and 52.8% of patients, respectively. Necroinflammatory activity was the only factor independent of steatosis (adjusted odds ratio = 5.3, 95% CI: 1.6 to 17.9). When necroinflammatory activity was removed from the model, HCV genotype 3 and body mass index (BMI) were significantly associated with steatosis.

CONCLUSIONS

Liver inflammation, HCV genotype 3, and BMI are associated with steatosis, a common finding in HCV-HIV-coinfected patients.

Thematic review series: Adipocyte Biology. Lipodystrophies: windows on adipose biology and metabolism

The lipodystrophies are characterized by loss of adipose tissue in some anatomical sites, frequently with fat accumulation in nonatrophic depots and ectopic sites such as liver and muscle. Molecularly characterized forms include Dunnigan-type familial partial lipodystrophy (FPLD), partial lipodystrophy with mandibuloacral dysplasia (MAD), Berardinelli-Seip congenital generalized lipodystrophy (CGL), and some cases with Barraquer-Simons acquired partial lipodystrophy (APL). The associated mutant gene products include 1) nuclear lamin A in FPLD type 2 and MAD type A; 2) nuclear lamin B2 in APL; 3) nuclear hormone receptor peroxisome proliferator-activated receptor gamma in FPLD type 3; 4) lipid biosynthetic enzyme 1-acylglycerol-3-phosphate O-acyltransferase 2 in CGL type 1; 5) integral endoplasmic reticulum membrane protein seipin in CGL type 2; and 6) metalloproteinase ZMPSTE24 in MAD type B. An unresolved question is whether metabolic disturbances are secondary to adipose repartitioning or result from a direct effect of the mutant gene product. Careful analysis of clinical, biochemical, and imaging phenotypes, using an approach called "phenomics," reveals differences between genetically stratified subtypes that can be used to guide basic experiments and to improve our understanding of common clinical entities, such as metabolic syndrome or the partial lipodystrophy syndrome associated with human immunodeficiency virus infection.

Impact of human immunodeficiency virus infection on the prevalence and severity of steatosis in patients with chronic hepatitis C virus infection

BACKGROUND/AIMS

Although steatosis is strongly associated with hepatitis C virus (HCV) infection, little is known about this finding in patients coinfected with human immunodeficiency virus (HIV) and HCV. The aims of the present study were to determine the prevalence and severity of steatosis in HIV/HCV coinfected patients.

METHODS

Consecutive patients undergoing liver biopsy were prospectively identified and were interviewed to obtain detailed demographic and clinical data. Steatosis was scored according to the percentage of hepatocytes involved: 0 (none), 1 (<33%), 2 (33-66%), or 3 (>66%); fibrosis was scored on a scale from 0 to 4.

RESULTS

A total of 708 patients were enrolled, including 154 with HIV/HCV coinfection and 554 with HCV monoinfection. Steatosis of any grade (72.1 vs. 52.0%, P<0.001), grade 2/3 steatosis (48.1 vs. 20.2%, P<0.001), and stage 3/4 fibrosis (43.5 vs. 30.0%, P=0.002) were significantly more common in coinfected patients. Compared to HCV monoinfected subjects, HIV/HCV coinfection was associated with a significantly increased odds of steatosis of any grade (OR=3.21; 95% CI, 1.84-5.60) and grade 2/3 steatosis (OR=5.63; 95% CI, 3.05-10.36) after adjusting for potential confounding variables. Among coinfected patients, the fibrosis progression rate increased in a linear fashion with the grade of steatosis.

CONCLUSIONS

Steatosis is more common and more severe in HIV/HCV coinfected patients than in those with HCV monoinfection.

HIV-related liver disease: infections versus drugs

HIV-infected individuals have myriad causes of hepatotoxicity that range from mild hepatitis to significant liver failure with its associated morbidity and mortality, especially in the setting of chronic viral hepatitis (HCV and HBV). Immune restoration by HAART therapy can contribute liver-related toxicity in HIV-coinfected patients. Clinicians need to be aware of this problem and individualize management in this challenging clinical scenario. Avoidance of potentially hepatotoxic agents or close monitoring during treatment of HIV may prevent liver failure in patients who have HIV. Furthermore, vaccination against hepatitis A virus and HBV in nonimmune HIV individuals may prevent acquisition of hepatitis A virus and HBV infections in patients who have HIV. Finally, treatment of HIV, and, if appropriate, treatment of those who are coinfected with HCV and HBV with close monitoring, may improve the outcome of patients who have HIV and are at risk fo r significant hepatotoxicity during treatment from immune restoration or hypersensitivity reactions.

Non-alcoholic fatty liver disease in HIV-positive patients predisposes for acute-on-chronic liver failure: two cases

Non-alcoholic fatty liver disease is a prominent feature in HIV-positive patients. We present two patients with long-lasting HIV-infection who suffered from this disease, as induced by highly active anti-retroviral therapy (HAART). The patients developed acute-on-chronic (AOC) liver failure after either (case 1) acute infection with hepatitis A virus (HAV) or (case 2) methamphetamine abuse ('Ecstasy'). Approximately 1 week after visiting an area endemic for HAV, case 1, a male patient, presented with icterus, elevated liver transaminases and HAV IgM. Previous examinations had demonstrated normal liver transaminase activities while hepatic steatosis had been suspected. He developed complications associated with liver failure including renal failure as well as pleural and pericardial effusions. Case 2, a second male patient, developed both liver failure and lactic acidosis 24 h after methamphetamine abuse. Both patients suffered from fatty liver in the pre-acute stage as indicated by ultrasound examination. After developing symptoms of liver failure, HAART was discontinued in both patients. Follow-up visits demonstrated that the patients recovered clinically with almost normalized laboratory parameters. In HIV infection, HAART-induced hepatopathological alterations may exist despite the absence of relevant laboratory parameters. These patients are likely to develop AOC liver failure when subjected to acute risk factors such as hepatitis viruses and narcotics or other drugs. In patients treated with HAART, we thus highly recommend hepatitis A and B virus vaccinations, and close monitoring of liver parameters.