[Treatment of chronic itch in systemic disease. Current standards]

Plasmapheresis exerts a long-lasting antipruritic effect in severe cholestatic itch

BACKGROUND & AIMS

The amelioration of refractory cholestatic pruritus after plasmapheresis has been reported in single patients. Here, we analyse the efficacy of plasmapheresis in a cohort of patients with primary biliary cholangitis (PBC).

METHODS

Seventeen consecutive patients with PBC (age range 39-85 years, 16 females, 9 with cirrhosis) and refractory pruritus underwent 129 plasmapheresis procedures during 40 admissions. Pruritus was quantified by the 10-point numeric rating scale (NRS) before and after plasmapheresis, as well as ~30 and ~90 days later.

RESULTS

The mean pruritus before plasmapheresis did not differ between patients with and without cirrhosis (P>.05). Cirrhotics presented, however, with significantly higher serum alanine aminotransferase (ALT), aspartate transaminase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP) and bilirubin before plasmapheresis. Plasmapheresis decreased itching to NRS≤5 in all but five admissions: Mean pruritus decreased from 8.3±1.4 to 3.1±2.2 (P<.0001) in the entire cohort. It also led to a significant decrease in serum ALT, ALP, AST, GGT (all P<.001) and bilirubin (P=.002). Antipruritic effect persisted throughout the 90-days follow-up (P<.0001). The amelioration of pruritus was not affected by the presence of cirrhosis.

CONCLUSIONS

Plasmapheresis is a promising method for reducing intractable itch in a significant proportion of PBC patients regardless of liver fibrosis. Long-lasting improvement of symptoms requires repeated procedures.

Hepatitis C virus-associated pruritus: Etiopathogenesis and therapeutic strategies

In addition to its contributing role in the development of chronic liver diseases, chronic hepatitis C virus (HCV) infection is associated with extrahepatic manifestations, particularly, cutaneous-based disorders including those with pruritus as a symptom. Pruritus is frequently associated with the development of chronic liver diseases such as cholestasis and chronic viral infection, and the accumulation of bile acids in patients’ sera and tissues as a consequence of liver damage is considered the main cause of pruritus. In addition to their role in dietary lipid absorption, bile acids can trigger the activation of specific receptors, such as the G protein-coupled bile acid receptor (GPBA/ TGR5). These types of receptors are known to play a crucial role in the modulation of the systemic actions of bile acids. TGR5 expression in primary sensory neurons triggers the activation of the transient receptor potential vanilloid 1 (TRPV1) leading to the induction of pruritus by an unknown mechanism. Although the pathologic phenomenon of pruritus is common, there is no uniformly effective therapy available. Understanding the mechanisms regulating the occurrence of pruritus together with the conduction of large-scale clinical and evidence-based studies, may help to create a standard treatment protocol. This review focuses on the etiopathogenesis and treatment strategies of pruritus associated with chronic HCV infection.

[Cutaneous manifestations in renal diseases]

In addition to general skin changes like pallor or dryness and the frequent, often excruciating nephrogenic pruritus, specific diseases in patients with renal failure may occur. Acquired perforating dermatoses are usually also highly pruritic. Calciphylaxis is a severe disease with poor prognosis. Nonhealing wounds with superinfection and progression to sepsis are characteristic. Bullous lesions can be caused by disturbances in porphyrin metabolism. Nephrogenic systemic fibrosis is a disease which was first described in 2000. Its incidence is already on the decline. Furthermore, this article provides an overview of systemic diseases which have both skin symptoms and kidney changes. These include connective tissue diseases, vasculitis or sarcoidosis and amyloidosis. After a kidney transplantation, particular attention must be paid to the development of skin tumors and infections. The last part of this article is dedicated to genodermatoses with skin and renal involvement, where numerous causative mutations have already been characterized. Knowing the correlations of characteristic skin symptoms and specific, potentially life-threatening kidney disease is important in order to initiate further investigations and steps such as referral to nephrologists at an early stage.