Hepatitis C virus and kidney: a strong association with different clinical aspects

Understanding the relationship between HCV infection and progression of kidney disease

Hepatitis C virus (HCV) can cause a range of kidney diseases. HCV is the primary cause of mixed cryoglobulinaemia, which leads to cryoglobulinaemic vasculitis and cryoglobulinaemic glomerulonephritis (GN). Patients with acute cryoglobulinaemic vasculitis often exhibit acute kidney disease due to HCV infection, which typically progresses to acute kidney injury (AKI). HCV also increases the risk of chronic kidney disease (CKD) and the likelihood of developing end-stage renal disease (ESRD). Currently, direct-acting antiviral agents (DAAs) can be used to treat kidney disease at different stages. This review focuses on key findings regarding HCV and kidney disease, discusses the impact of DAAs, and highlights the need for further research and treatment.

Efficacy and safety of new direct-acting antivirals in kidney transplant recipients with chronic hepatitis C: a single-center study

Background

The recent interferon-free direct-acting antiviral (DAA) regimens have very good safety and efficacy profiles and are highly recommended for kidney transplant (KT) recipients with chronic hepatitis C (CHC).

Methods

All KT recipients with CHC followed at our hospital and who received therapy with the current DAAs were included. At the baseline visit, demographic, clinical and laboratory variables before and after KT, as well as at the commencement of DAAs, at the end of antiviral therapy and the end of follow up, were recorded, including assessment of glomerular filtration rate (eGFR). The changes in eGFR (DGFR) between baseline and end of therapy (1^st period), and between end of therapy and end of follow up (2^nd period), were evaluated.

Results

Twelve KT recipients were retrospectively evaluated: 2 had received antiviral therapy in the past; 4 (33.3%) patients had genotype 1 and 3 (25%) genotype 4 CHC. The median stiffness was 11.9 kPa (range 5-16.8), while 5 patients, none with decompensated cirrhosis, had stiffness >12.5 kPa. Eight patients received a sofosbuvir-containing antiviral regimen (Group 1) and 4 patients received an antiviral regimen without sofosbuvir (Group 2). Eleven (91.7%) patients achieved a sustained virological response (SVR). One patient discontinued DAAs early after treatment and did not achieve SVR. Otherwise, DAAs were well tolerated and no rejection episode was recorded. The DGFRs in the 1^st period and 2^nd period did not differ significantly between Group 1 and Group 2 patients.

Conclusion

In this real-world study of KT recipients with CHC, the high efficacy and clinically acceptable tolerability of DAAs were confirmed.

Antiviral therapy reduces risk of haemorrhagic stroke in patients with HCV infection: a nationwide cohort study

BACKGROUND

The tendency for haemorrhagic stroke in patients with chronic HCV infection has emerged recently but the finding may be confounded by comorbidities. Proving the causality between HCV infection and haemorrhagic stroke is mandatory. Our study was designed to investigate the incidence of intracranial haemorrhage in HCV-infected patients with and without treatment.

METHODS

In the 11-year and population-based retrospective study, we acquired data from the Taiwan National Health Insurance Research Database. The patients with major comorbidities were excluded and 97,198 HCV-infected patients were included for analysis. Treated and untreated cohorts were matched with propensity score to make the confounding factors in two groups comparable. Cox proportional hazard regression analysis was performed to evaluate the hazard ratio of haemorrhagic stroke in the cohorts. We applied survival analysis to compare the cumulative incidence of outcome events between the two cohorts.

RESULTS

After matching, the incidence density (ID) of haemorrhagic stroke in the untreated cohort is significantly higher than in the treated cohort (ID: 1.0 versus 0.6 events per 1,000 person-years; P=0.0014). The adjusted hazard ratio (aHR) of haemorrhagic stroke is significantly reduced in the treated group (P<0.05). Cumulative incidence of haemorrhagic stroke is significantly lower in the treated group than in the untreated group (P=0.013).

CONCLUSIONS

The study demonstrates that antiviral therapy significantly reduces the events of intracranial haemorrhage in HCV-infected patients and consolidates the novel concept that chronic HCV infection is a risk factor for haemorrhagic stroke.

Hepatitis C co-infection is associated with an increased risk of incident chronic kidney disease in HIV-infected patients initiating combination antiretroviral therapy

BACKGROUND

Combination antiretroviral therapy (cART) has reduced mortality from AIDS-related illnesses and chronic comorbidities have become prevalent among HIV-infected patients. We examined the association between hepatitis C virus (HCV) co-infection and chronic kidney disease (CKD) among patients initiating modern antiretroviral therapy.

METHODS

Data were obtained from the Canadian HIV Observational Cohort for individuals initiating cART from 2000 to 2012. Incident CKD was defined as two consecutive serum creatinine-based estimated glomerular filtration (eGFR) measurements <60 mL/min/1.73m² obtained ≥3 months apart. CKD incidence rates after cART initiation were compared between HCV co-infected and HIV mono-infected patients. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression.

RESULTS

We included 2595 HIV-infected patients with eGFR >60 mL/min/1.73m² at cART initiation, of which 19% were HCV co-infected. One hundred and fifty patients developed CKD during 10,903 person-years of follow-up (PYFU). The CKD incidence rate was higher among co-infected than HIV mono-infected patients (26.0 per 1000 PYFU vs. 10.7 per 1000 PYFU). After adjusting for demographics, virologic parameters and traditional CKD risk factors, HCV co-infection was associated with a significantly shorter time to incident CKD (HR 1.97; 95% CI: 1.33, 2.90). Additional factors associated with incident CKD were female sex, increasing age after 40 years, lower baseline eGFR below 100 mL/min/1.73m², increasing HIV viral load and cumulative exposure to tenofovir and lopinavir.

CONCLUSIONS

HCV co-infection was associated with an increased risk of incident CKD among HIV-infected patients initiating cART. HCV-HIV co-infected patients should be monitored for kidney disease and may benefit from available HCV treatments.

Concentration Monitoring of Plasma Ribavirin: Validation of a Liquid Chromatography-Mass Spectrometric Method and Clinical Sample Collection

BACKGROUND

A liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for routine measurement of ribavirin concentrations in EDTA-anticoagulated plasma.

METHODS

After protein precipitation, we used a bridged ethylene hybrid (hydrophilic interaction) chromatography column, 0.1 mmol/L ammonium formate pH 3.0, and a gradient of 85%-96% acetonitrile to achieve baseline separation of ribavirin from isobaric uridine. Quantitation was assured using both primary (m/z 245.3 > 113.0) and secondary transitions (m/z 245.3 > 96.0) of the protonated species. Chromatographic separation and column washing also negated interference from major phospholipid species.

RESULTS

There was a linear relationship between concentration and response to 10 mg/L, with a minimum detectable level and a minimum level of quantitation both of 0.1 mg/L. Imprecision within the assay was <10% at 0.1 mg/L and <6% between assays for concentrations >0.4 mg/L. Bias was <4%. In clinical samples (n = 12), there was no difference in ribavirin concentrations obtained by an established liquid chromatographic assay with ultraviolet detection. Ribavirin concentrations were stable in plasma stored at room temperature for 3 days but then decreased significantly on day 7. Plasma concentrations were stable for 15 weeks at -20 °C. Concentrations in plasma separated from whole blood at room temperature fell by a median of 19.4% at 4 hours and then rose substantially (median 251% by 3 days). Dose-normalized ribavirin concentrations reached a steady state after a mean of >6 weeks treatment in 76 patients with hepatitis C.

CONCLUSIONS

A hydrophilic interaction liquid chromatography-tandem mass spectrometric method to measure ribavirin in plasma was developed. Samples for ribavirin estimation should be kept at 4 °C, separated within 2 hours of collection and stored at 4 °C before analysis, with long-term storage at -20 °C. This method was applied to a study of the ribavirin therapeutic monitoring in patients with hepatitis C.

Frequent injection cocaine use increases the risk of renal impairment among hepatitis C and HIV coinfected patients

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Objective:

To examine the association between injection cocaine use, hepatitis C virus (HCV) infection, and chronic renal impairment (CRI).

Design:

Prospective observational cohort study of HIV–HCV coinfected patients.

Methods:

Data from 1129 participants in the Canadian Co-Infection Cohort with baseline and follow-up serum creatinine measurements between 2003 and 2014 were analyzed. Prevalent and incident cohorts were created to examine the association between self-reported past, current, and cumulative cocaine use and chronic HCV with CRI. CRI was defined as an estimated glomerular filtration rate below 70 ml/min per 1.73 m². Multivariate logistic regression was used to calculate odds ratios, and discrete-time proportional-hazards models were used to calculate hazard ratios for cocaine use, in the two respective cohorts, adjusted for HCV RNA and important demographic, HIV disease stage, and comorbidity confounders.

Results:

Eighty-seven participants (8%) had prevalent CRI. Past injection cocaine use was associated with a two-fold greater risk of prevalent CRI [odds ratio 2.03, 95% confidence interval (CI) 0.96, 4.32]. During follow-up, 126 of 1061 participants (12%) developed incident CRI (31 per 1000 person-years). Compared to nonusers, heavy (≥ 3 days/week) and frequent injection cocaine users (≥75% of follow-up time) experienced more rapid progression to CRI (hazard ratio 2.65, 95% CI 1.35, 5.21; and hazard ratio 1.82, 95% CI 1.07, 3.07, respectively). There was no association between chronic HCV and CRI in either cohort.

Conclusion:

After accounting for HCV RNA, frequent and cumulative injection cocaine abuse was associated with CRI progression and should be taken into consideration when evaluating impaired renal function in HIV–HCV coinfection.

Increase in nonhepatic diagnoses among persons with hepatitis C hospitalized for any cause, United States, 2004-2011

Although persons with hepatitis C virus (HCV) infection may experience nonhepatic illnesses, little is known about the frequency of and trends in such conditions in a population-based sample of HCV-infected persons. Using hospitalization data collected during 2004-2011 from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project, we examined trends in comorbidities among all hospitalizations that included either a principal or secondary HCV diagnostic code (i.e., HCV was not necessarily the cause for hospitalization). We also compared comorbidities among all persons aged 45-64 years hospitalized with and without principal or secondary HCV diagnostic codes. The estimated number of hospitalizations among persons with HCV infection increased from 850,490 in 2004-2005 to 1,178,633 in 2010-2011; mean age at hospitalization was 50 years in 2004-2005 and 52.5 years in 2010-2011. There were significant increases in the prevalence of most medical and psychiatric comorbidities; the largest were for lipid disorders, chronic kidney disease and obesity. Among HCV-infected aged 45-64 persons hospitalized for any cause, the prevalence of alcohol /substance abuse, mental disorders, chronic kidney disease, pneumonia, hepatitis B virus infection and HIV infection were significantly higher than those aged 45-64 persons hospitalized without HCV infection (P < 0.001 for all). The prevalence of cryoglobulinaemia, vasculitis, nephrotic syndrome or membranoproliferative glomerulonephritis and porphyria cutanea tarda among hospitalizations with HCV infection was consistently low during the study period (i.e., <0.5%). The increase we observed in nonhepatic comorbidities associated with a high risk of HCV-related complications has important implications for the current HCV treatment recommendations in a greatly expanded treatment population.

Neutrophil Gelatinase-Associated Lipocalin: A New Marker of Renal Function in C-Related End Stage Liver Disease

Background/Aims. Renal impairment is a common complication of cirrhosis. Serum creatinine is less sensitive in these patients. Measurement of the glomerular filtration rate (GFR) is the gold standard but time consuming. The aim is to validate plasma NGAL (pNGAL) and urinary NGAL (uNGAL) as markers of renal function in patients with HCV related cirrhosis. Patient and Methods. One hundred HCV related end stage liver cirrhosis patients were randomized into two groups: Group I (n = 35), patients with GFR < 60 mL/m measured by isotope scanning of the kidney (Renogram), and Group II (n = 65), patients with GFR ≥ 60 mL/m. The pNGAL and uNGAL were measured within 2 days of the Renogram. Results. Both groups were matched with age, sex, and Child Pugh score. There was statistically significant difference between both groups regarding serum creatinine (1.98 ± 1.04 versus 1.38 ± 0.88 mg/dL; p = 0.003) and pNGAL level (5.79 ± 2.06 versus 7.25 ± 3.30 ng/dL; p = 0.019). Both groups were comparable (p > 0.05) for the uNGAL (6.00 ± 0.78 versus 6.03 ± 0.96 ng/mL). Unlike uNGAL, the pNGAL positively correlated with total GFR by Renogram (r = 0.3; p = 0.001). With a cutoff ≥4 ng/mL, pNGAL had 94.3% sensitivity and 1.5% specificity and PPV = 34, NPV = 33.3, LR+ = −175.1, and LR− = −60.6. Conclusion. The pNGAL is a promising marker of the renal function in patients with cirrhosis.

Sleep apnea and the risk of chronic kidney disease: a nationwide population-based cohort study

STUDY OBJECTIVES

Sleep apnea (SA) is characterized by apnea during sleep and is associated with cardiovascular diseases and an increase in all-cause mortality. Chronic kidney disease (CKD) is a global health problem that has placed a substantial burden on healthcare resources. However, the relationship between SA and the incidence of CKD is not clear. This study aimed to determine whether SA is an independent risk factor for the development of CKD.

DESIGN

Retrospective cohort study.

SETTING

National Health Insurance Research Database (NHIRD) of Taiwan.

PATIENTS OR PARTICIPANTS

A total of 4,674 adult patients (age ≥ 30 y) in whom SA was newly diagnosed from 2000 to 2010 were included, together with 23,370 non-SA patients as the comparison group. The two groups were frequency-matched for sex, age, and year of receiving medical service. Each individual was followed until 2011.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

These two groups were monitored and observed for the occurrence of CKD. Patients with SA experienced a 1.94-fold increase (95% confidence interval [CI], 1.52-2.46; P < 0.001) in the incidence of CKD, which was independent of sex, age, and comorbid medical conditions. Additionally, they showed a 2.2-fold increase (95% CI, 1.31-3.69; P < 0.01) in the incidence of end-stage renal disease (ESRD).

CONCLUSIONS

Patients with sleep apnea are at increased risk for chronic kidney disease and end-stage renal disease compared with the general population. As such, screening renal function and treatment of chronic kidney disease is an important issue in patients with sleep apnea.

Neutrophil Gelatinase-Associated Lipocalin: A New Marker of Renal Function in C-Related End Stage Liver Disease

Background/Aims. Renal impairment is a common complication of cirrhosis. Serum creatinine is less sensitive in these patients. Measurement of the glomerular filtration rate (GFR) is the gold standard but time consuming. The aim is to validate plasma NGAL (pNGAL) and urinary NGAL (uNGAL) as markers of renal function in patients with HCV related cirrhosis.Patient and Methods. One hundred HCV related end stage liver cirrhosis patients were randomized into two groups: Group I (n=35), patients with GFR < 60 mL/m measured by isotope scanning of the kidney (Renogram), and Group II (n=65), patients with GFR ≥ 60 mL/m. The pNGAL and uNGAL were measured within 2 days of the Renogram.Results. Both groups were matched with age, sex, and Child Pugh score. There was statistically significant difference between both groups regarding serum creatinine (1.98 ± 1.04 versus 1.38 ± 0.88 mg/dL;p=0.003) and pNGAL level (5.79 ± 2.06 versus 7.25 ± 3.30 ng/dL;p=0.019). Both groups were comparable (p>0.05) for the uNGAL (6.00 ± 0.78 versus 6.03 ± 0.96 ng/mL). Unlike uNGAL, the pNGAL positively correlated with total GFR by Renogram (r=0.3;p=0.001). With a cutoff ≥4 ng/mL, pNGAL had 94.3% sensitivity and 1.5% specificity and PPV = 34, NPV = 33.3, LR+ = −175.1, and LR− = −60.6.Conclusion. The pNGAL is a promising marker of the renal function in patients with cirrhosis.

Neutrophil Gelatinase-Associated Lipocalin: A New Marker of Renal Function in C-Related End Stage Liver Disease

Background/Aims. Renal impairment is a common complication of cirrhosis. Serum creatinine is less sensitive in these patients. Measurement of the glomerular filtration rate (GFR) is the gold standard but time consuming. The aim is to validate plasma NGAL (pNGAL) and urinary NGAL (uNGAL) as markers of renal function in patients with HCV related cirrhosis.Patient and Methods. One hundred HCV related end stage liver cirrhosis patients were randomized into two groups: Group I (n=35), patients with GFR < 60 mL/m measured by isotope scanning of the kidney (Renogram), and Group II (n=65), patients with GFR ≥ 60 mL/m. The pNGAL and uNGAL were measured within 2 days of the Renogram.Results. Both groups were matched with age, sex, and Child Pugh score. There was statistically significant difference between both groups regarding serum creatinine (1.98 ± 1.04 versus 1.38 ± 0.88 mg/dL;p=0.003) and pNGAL level (5.79 ± 2.06 versus 7.25 ± 3.30 ng/dL;p=0.019). Both groups were comparable (p>0.05) for the uNGAL (6.00 ± 0.78 versus 6.03 ± 0.96 ng/mL). Unlike uNGAL, the pNGAL positively correlated with total GFR by Renogram (r=0.3;p=0.001). With a cutoff ≥4 ng/mL, pNGAL had 94.3% sensitivity and 1.5% specificity and PPV = 34, NPV = 33.3, LR+ = −175.1, and LR− = −60.6.Conclusion. The pNGAL is a promising marker of the renal function in patients with cirrhosis.

Deteriorating renal function and clinical outcomes in HIV-positive persons

OBJECTIVES

To determine the relationship between measures of renal function [current estimated glomerular filtration rate (eGFR) and proportion of follow-up with a low eGFR (%FU ≤60 ml/min)] and fatal/ nonfatal AIDS, non-AIDS events and all-cause mortality.

DESIGN

An observational, longitudinal cohort study of 12 155 persons from EuroSIDA.

METHODS

Persons with at least one eGFR measurement after 1 January 2004, using the CKD-EPI formula, were included. Poisson regression analyses were used to determine whether current eGFR or %FU of 60 ml/min or less were independent prognostic markers for clinical events.

RESULTS

During 61 425 person-years of follow-up (PYFU), the crude incidence of deaths was 11.1/1000 PYFU [95% confidence interval (CI) 10.0-12.1] at current eGFR more than 90 ml/min and 199.6 (95% CI 1144.3-254.3/1000 PYFU) when current eGFR was 30 ml/min or less. Corresponding figures for AIDS were 12.2 (11.1-13.3) and 63.9 (36.5-103.7) and for non-AIDS were 16.0 (14.8-17.3) and 203.6 (147.7-259.5). After adjustment, current eGFR of 30 ml/min or less was a strong predictor of death [adjusted incidence rate ratios (aIRR) 4.35; 95% CI 3.20-5.91] and non-AIDS events (3.63; 95% CI 2.57-5.13), although the relationship with AIDS was less strong (1.45; 95% CI 1.01-2.08). After adjustment, %FU of 60 ml/min or less was associated with a 22% increased incidence of death (aIRR 1.22 per 10% longer; 95% CI 1.18-1.27), a 13% increased incidence of non-AIDS events (95% CI 1.08-1.18) and a 15% increased incidence of AIDS events (95% CI 1.06-1.24).

CONCLUSION

Both current eGFR and %FU of 60 ml/min or less were associated with death and non-AIDS events in HIV-positive persons. Our findings highlight the association between underlying renal dysfunction and morbidity and mortality in HIV infection, although reverse causality cannot be excluded.

Transjugular renal biopsy in a case of nephrotic syndrome with extrahepatic portal venous obstruction

Renal biopsy in patients with nephrotic syndrome helps to establish the pathological diagnosis and subsequent treatment. In certain circumstances, biopsies are difficult to obtain because of the risk of bleeding. We report a case where renal biopsy was obtained through the transjugular route in a patient who had nephrotic syndrome with extrahepatic portal venous obstruction.

Differential regulation of interleukin-12 (IL-12)/IL-23 by Tim-3 drives T(H)17 cell development during hepatitis C virus infection

Cytokine production by innate immunity is critical for shaping the adaptive immunity through regulation of T cell differentiation. In this report, we studied T cell immunoglobulin mucin domain protein 3 (Tim-3) expression on monocytes and its regulatory effect on interleukin-12 (IL-12)/IL-23 production by CD14(+) monocytes, as well as IL-17 production by CD4(+) T cells in individuals with chronic hepatitis C virus (HCV) infection. We found that Tim-3 and IL-23p19 are highly expressed and that IL-12p35 is inhibited in human CD14(+) monocytes, while IL-17 expression is upregulated in CD4(+) T cells, in chronically HCV-infected individuals compared to healthy subjects. Interestingly, Tim-3 expression is closely associated with the differential regulation of IL-12/IL-23 expression in CD14(+) monocytes and correlated to IL-17 production by CD4(+) T cells. These Tim-3-associated IL-12/IL-23/IL-17 dysregulations in HCV-infected individuals are also recapitulated in vitro by incubating healthy monocytes or peripheral blood mononuclear cells with Huh-7 hepatoma cells transfected with HCV RNA. Importantly, blocking Tim-3 signaling on monocytes restores the balance of IL-12/IL-23 through the intracellular STAT3 signaling, which in turn reverses the upregulated IL-17 expression both ex vivo and in vitro. Our findings suggest that Tim-3-mediated differential regulation of IL-12/IL-23 drives T(H)17 cell development, a milieu favoring viral persistence and autoimmune phenomenon during HCV infection.

Hepatitis C virus viremia increases the incidence of chronic kidney disease in HIV-infected patients

BACKGROUND

Several studies have reported on an association between hepatitis C virus (HCV) antibody status and the development of chronic kidney disease (CKD), but the role of HCV viremia and genotype are not well defined.

METHODS

Patients with at least three serum creatinine measurements after 1 January 2004 and known HCV antibody status were included. Baseline was defined as the first eligible estimated glomerular filtration rate (eGFR) (Cockcroft-Gault equation), and CKD was either a confirmed (>3 months apart) eGFR of 60 ml/min per 1.73 m or less for patients with a baseline eGFR more than 60 ml/min per 1.73 m or a confirmed 25% decline in eGFR for patients with a baseline eGFR of 60 ml/min per 1.73 m or less. Incidence rates of CKD were compared between HCV groups (anti-HCV-negative, anti-HCV-positive with or without viremia) using Poisson regression.

RESULTS

Of 8235 patients with known anti-HCV status, 2052 (24.9%) were anti-HCV-positive of whom 983 (47.9%) were HCV-RNA-positive, 193 (9.4%) HCV-RNA-negative and 876 (42.7%) had unknown HCV-RNA. At baseline, the median eGFR was 97.6 (interquartile range 83.8-113.0) ml/min per 1.73 m. During 36123 person-years of follow-up (PYFU), 495 patients progressed to CKD (6.0%) with an incidence rate of 14.5 per 1000 PYFU (95% confidence interval 12.5-14.9). In a multivariate Poisson model, patients who were anti-HCV-positive with HCV viremia had a higher incidence rate of CKD, whereas patients with cleared HCV infection had a similar incidence rate of CKD compared with anti-HCV-negative patients. There was no association between CKD and HCV genotype.

CONCLUSION

Compared with HIV-monoinfected patients, HIV-positive patients with chronic rather than cleared HCV infection were at increased risk of developing CKD, suggesting a contribution from active HCV infection toward the pathogenesis of CKD.