Intractable pruritus in patients with hepatitis C virus

Systematic review: efficacy of therapies for cholestatic pruritus

Background

Pruritus is a symptom of several cholestatic liver diseases (CLDs) that can impair health-related quality of life (HRQoL). Despite evidence-based guideline therapy, managing cholestatic pruritus (CP) remains challenging, thus making the need for newer, more effective therapeutic agents more evident.

Objective

Our study evaluated the efficacy of existing CP therapies.

Design

Systematic review.

Data sources

From inception until March 2023, we conducted a comprehensive search of MEDLINE, Cochrane, EMBASE, Scopus, ClinicalTrial.gov, and other sources, including pharmaceutical webpages and conference proceedings published in English that reported on CP interventions.

Methods

Two reviewers independently conducted screening and full-text review of articles with extraction conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The methodological quality of studies included in our qualitative synthesis was assessed by using the Cochrane ROBINS-I and ROBINS-II tools for interventional studies and the National Heart, Lung, and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. The primary outcome assessed in our systematic review was the severity of CP after therapy.

Results

Of 3293 screened articles, 92 studies were eligible for inclusion in the qualitative synthesis. Some patients' HRQoL improved with evidence-based standard therapy. Others, particularly those with severe and refractory CP, often required conversion to or addition of experimental noninvasive (e.g., ondansetron) or extracorporeal liver support to alleviate CP. In addition, studies investigating a newer class drug, the ileal bile acid transporter inhibitor (IBATi), demonstrate its effectiveness in reducing serum bile acid and alleviating CP with sustained improvement noted in patients with the inherited childhood cholestatic disorders - progressive familial intrahepatic cholestasis and Alagille syndrome.

Conclusion

Our findings consolidate data on the efficacy of guideline-based approaches and newer therapies for CP. While the initial findings are promising, additional clinical trials will be needed to determine the full extent of IBATi's efficacy and potential use in treating other common CLDs. These results provide a foundation for future research and highlight the need for continued investigation into the management and treatment of CLDs.

Efficacy of Treatments for Cholestatic Pruritus: A Systemic Review and Meta-analysis

Cholestatic itch is a disabling symptom that may be secondary to liver or biliary diseases. Management of cholestatic pruritus is complex. A systematic review and meta-analysis on the efficacy of treatments for cholestatic pruritus were performed. PubMed and Cochrane Library were searched using the algorithm “(hepatitis OR cholestatic OR liver) AND (pruritus OR itch) AND (management OR treatment OR treatments)” for 1975–2019. Of the 2,264 articles identified, 93 were included in a systematic review and 15 in a meta-analysis (studies evaluating pruritus with a visual analogue scale). Some treatments act by reducing levels of pruritogens in the enterohepatic cycle, others modify the metabolism or secretion of these pruritogens, or act on pruritus pathways. A further possible treatment is albumin dialysis. However, due to many heterogeneities in the reviewed studies it is difficult to identify and recommend an optimum treatment. Only 15 studies were included in the meta-analysis, due to the small number of randomized studies using a visual analogue scale.

Blood cytokine, chemokine and gene expression in cholestasis patients with intractable pruritis treated with a molecular adsorbent recirculating system: a case series

BACKGROUND

The molecular adsorbent recirculating system (MARS) is an albumin-dialysis modality that has been investigated predominantly in patients with acute and acute-on-chronic liver failure.

OBJECTIVES

To report the clinical efficacy and safety of MARS therapy for intractable pruritus in cholestasis patients with stable chronic liver disease, characterizing the impact of MARS on cytokine levels and on the transcriptome in the blood compartment.

METHODS

MARS therapy was performed on three patients with cholestatic liver disease using 8 h runs for two consecutive days. The expression levels of 65 cytokines⁄chemokines and 24,000 genes were profiled by Luminex (Luminex Corporation, USA) and microarray, respectively.

RESULTS

A quality-of-life assessment demonstrated a marked improvement during therapy, which was sustained in two of three patients. No bleeding or infectious complications were observed. Bile acid levels were markedly reduced following MARS (mean [± SD] pretreatment 478.9±112.2 µmol⁄L versus post-treatment 89.7±68.8 µmol⁄L). Concordant decreases in cytokine⁄chemokine levels were noted for interleukin (IL)-1beta, IL-2, IL-6, IL-8, IL-12 (p40), RANTES, tranforming growth factor-alpha, tumour necrosis factor-alpha and thrombopoietin following MARS. On microarray profiling, biologically relevant concordant changes among all patients were evident for 20 different genes (10 upregulated and 10 downregulated). The upregulation of several potentially immune suppressive⁄regulatory genes (eg, early growth response 3 [EGR-3], ephrin-A2 [EFNA2] and serum amyloid A1 [SAA1]), concurrent with downregulation of genes involved in innate immunity (eg, toll-like receptor 4 interactor with leucine-rich repeats [TRIL]) and inflammation (eg, ephrin receptor B1 [EPHB1]), was observed.

CONCLUSIONS

This investigative approach offers new insights into intractable pruritus and suggests future therapeutic targets. The clinical benefit of MARS in cholestasis patients with intractable pruritus may not exclusively result from filtration of pruritogens, but also from systemic changes in cytokine⁄chemokine levels and changes in gene expression of blood cells.

ITCH regulates degradation of mutant glucocerebrosidase: implications to Gaucher disease

Inability to properly degrade unfolded or misfolded proteins in the endoplasmic reticulum (ER) leads to ER stress and unfolded protein response. This is particularly important in cases of diseases in which the mutant proteins undergo ER-associated degradation (ERAD), as in Gaucher disease (GD). GD is a genetic, autosomal recessive disease that results from mutations in the GBA1 gene, encoding the lysosomal enzyme acid β-glucocerebrosidase (GCase). We have shown that mutant GCase variants undergo ERAD, the degree of which is a major determinant of disease severity. Most ERAD substrates undergo polyubiquitination and proteasomal degradation. Therefore, one expects that mutant GCase variants are substrates for several E3 ubiquitin ligases in different cells. We tested the possibility that ITCH, a known E3 ubiquitin ligase, with a pivotal role in proliferation and differentiation of the skin, recognizes mutant GCase variants and mediates their polyubiquitination and degradation. Our results strongly suggest that ITCH interacts with mutant GCase variants and mediates their lysine 48 polyubiquitination and degradation.

Molecular Adsorbents Recirculating System dialysis in children with cholestatic pruritus

BACKGROUND

Cholestatic pruritus may severely compromise quality of life. The Molecular Adsorbents Recirculating System (MARS) allows removal of pruritogenic substances without exposure to foreign proteins. Pediatric data, however, are scant.

METHODS

We retrospectively analyzed the efficacy of MARS in three boys with severe cholestatic pruritus. They received a total of 135 MARS sessions during 8, 4, and 13 months prior to liver transplantation. Total serum bilirubin and bile acids were monitored, and pruritus was assessed by a numerical rating scale (NRS 0 = no pruritus, 10 = maximal pruritus).

RESULTS

MARS sessions were initially performed three times weekly at a mean duration of 6.3 ± 1.4 h. Sessions could be reduced to once weekly and once every other week in two patients. Pre-MARS plasma bile acid concentrations averaged 207 ± 67 μmol/l. They declined to 67 ± 9%, 48 ± 3%, 38 ± 14%, and 37 ± 5% of baseline within 2, 4, 6 and 8 h of therapy, respectively (all p < 0.05). The average interdialytic increase of plasma bile acids was 34 ± 33 μmol/l per day. Mean NRS score decreased from 6.5 ± 2.3 to 3.3 ± 2.9 (p < 0.01). Skin lesions from itching disappeared. All MARS treatments were well tolerated.

CONCLUSION

MARS dialysis substantially reduces cholestatic pruritus in children refractory to pharmacological treatment.