Study of pruritus in chronic hepatitis C patients

Chronic Kidney Disease-Associated Itch (CKD-aI) in Children-A Narrative Review

Chronic kidney disease (CKD) is a condition of widespread epidemiology and serious consequences affecting all organs of the organism and associated with significant mortality. The knowledge on CKD is rapidly evolving, especially concerning adults. Recently, more data is also appearing regarding CKD in children. Chronic itch (CI) is a common symptom appearing due to various underlying dermatological and systemic conditions. CI may also appear in association with CKD and is termed chronic kidney disease-associated itch (CKD-aI). CKD-aI is relatively well-described in the literature concerning adults, yet it also affects children. Unfortunately, the data on paediatric CKD-aI is particularly scarce. This narrative review aims to describe various aspects of CKD-aI with an emphasis on children, based on the available data in this population and the data extrapolated from adults. Its pathogenesis is described in details, focusing on the growing role of uraemic toxins (UTs), as well as immune dysfunction, altered opioid transmission, infectious agents, xerosis, neuropathy and dialysis-associated aspects. Moreover, epidemiological and clinical aspects are reviewed based on the few data on CKD-aI in children, whereas treatment recommendations are proposed as well, based on the literature on CKD-aI in adults and own experience in managing CI in children.

Prevalence of pruritus in patients with chronic liver disease: A multicenter study

AIM

Pruritus is a common comorbidity in chronic liver disease. The aim of this study was to clarify the prevalence of pruritus and its characteristics in patients with chronic liver disease.

METHODS

A total of 1631 patients with chronic liver disease who attended one of nine joint-research facilities from January to June 2016 were enrolled. We investigated the prevalence of pruritus, itch location, itch duration, daily itch fluctuation, seasonal itch exacerbation, treatment drugs, and therapeutic effects using a medical interview questionnaire.

RESULTS

The median age was 66 years and 890 (54.6%) patients were women. The prevalence of pruritus was 40.3% (658/1631), and it differed according to the underlying liver disease. The most frequent body location for pruritus was on the back (63.1%). Pruritus duration was more than 6 months in 252 (38.3%) patients. The severity of pruritus, assessed using a visual analog scale, was higher during the day than at night (median, 4 vs. 3, P < 0.001). Seasonal exacerbation was observed in 296 (45.0%) patients. Although 301 (45.7%) patients were treated with antipruritic agents, 57.8% (174/301) patients reported an insufficient effect. Active hepatitis B virus infection (odds ratio [OR], 2.51; P = 0.043), primary biliary cholangitis (OR, 3.69; P = 0.018), diabetes (OR, 1.57; P = 0.010), and aspartate aminotransferase ≥60 U/L (OR, 2.06; P = 0.011) were independent factors associated with pruritus.

CONCLUSION

The prevalence of pruritus varies according to the chronic liver disease etiology. Underlying liver disease, aspartate aminotransferase ≥60 U/L, and comorbid diabetes are factors associated with pruritus in patients with chronic liver disease.

Predictors of pruritus in patients with chronic liver disease and usefulness of nalfurafine hydrochloride

AIM

Pruritus is one of the complications of chronic liver disease, and it is important to investigate the predictors.

METHODS

Six hundred and seventy-three consecutive Japanese patients with chronic liver disease were retrospectively investigated for itch severity. Furthermore, 138 of all 673 patients were introduced to nalfurafine hydrochloride, and the improvement of itch severity was evaluated. The itch severity was self-assessed using the pruritus scores by Kawashima's criteria and visual analog scale.

RESULTS

Two hundred and twenty-nine of the 673 patients (34.0%) were evaluated as 1 point or more of pruritus severity of Kawashima's criteria, and 46 patients (6.8 %) as 3 points or more. Multivariate analysis established that being negative for hepatitis B surface antigen (HBsAg) and presence of hepatocellular carcinoma (HCC) were significant determinants of pruritus (≥1 point of Kawashima's criteria), and being negative for HBsAg and having lower levels of platelet count were significant determinants of severe pruritus (≥3 points). Ninety-three of the 138 patients (67.4%) with nalfurafine hydrochloride indicated improvement of itch, defined as a decrease in VAS of 50 mm or more. There were no significant differences in treatment efficacy of nalfurafine hydrochloride, regardless of the three predictors of pruritus (HBsAg, HCC and platelet count).

CONCLUSION

The present retrospective study indicated the predictors for pruritus, based on the large number of patients with chronic liver disease. Furthermore, this study demonstrated that nalfurafine hydrochloride may be useful for pruritus, regardless of the predictors.

Efficacy of nalfurafine hydrochloride in patients with chronic liver disease with refractory pruritus: A randomized, double-blind trial

AIMS

Patients with chronic liver disease sometimes develop cholestasis, which induces severe whole-body pruritus that may disrupt daily activities and sleep. To determine the efficacy of nalfurafine hydrochloride (5 μg), which is a selective κ-opioid receptor agonist, in improving pruritus, we undertook a double-blind placebo-controlled study in patients with chronic liver disease with refractory pruritus. Nalfurafine hydrochloride at 2.5 μg was also used to evaluate the dose-response relationship.

METHODS

In total, 318 subjects were randomly assigned to receive the placebo or nalfurafine hydrochloride (2.5 or 5 μg) given orally once daily for 84 consecutive days. Pruritus was assessed based on the visual analog scale and pruritus scores.

RESULTS

Changes in the visual analog scale at week 4 (last observation carried forward) were significantly greater in the nalfurafine hydrochloride groups at 28.56 and 27.46 mm in the 2.5 μg and 5 μg groups, respectively, compared to 19.25 mm in the placebo group (P = 0.0022 and 0.0056, respectively). The major adverse drug reactions (ADRs) included pollakiuria (including nocturia), somnolence, insomnia (including middle insomnia), and constipation. Most ADRs were mild.

CONCLUSIONS

Nalfurafine hydrochloride (2.5 or 5 μg daily) was effective in the treatment of refractory pruritus in patients with chronic liver disease. Furthermore, no clinically significant ADRs were observed at either dose.

Long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients: Patient-reported outcome based analyses

Background and aim

Among various symptoms accompanied with chronic liver disease, pruritus affects the quality of life of patients, causing physical and mental stress, and worsens hepatic function. Recently, κ-opioid receptor agonist, nalfurafine hydrochloride was approved to treat central pruritus in patients with liver disease in Japan. This study aimed to assess the long-term efficacy and safety of nalfurafine hydrochloride on pruritus in chronic liver disease patients.

Methods

A patient-reported outcome using questionnaire-based methods was used for 41 liver disease patients with or without pruritus symptoms. Nalfurafine hydrochloride (2.5 μg/day) was orally administered to 18 patients suffering from pruritus symptoms and whose current treatment was not effective. The same questionnaires and visual analogue scales (VAS) were repeatedly followed up for the patients for the entire follow-up period, and biochemical analyses were performed to evaluate the safety of the treatment.

Results

Pruritus completely disappeared in seven of 18 cases, and VAS scores showed a decreasing trend over time from the start of nalfurafine hydrochloride administration in all patients who received the medication. Among 11 patients who were followed up for more than 12 weeks, nine patients showed continuous improvement of symptoms, and this progress was still apparent at ≥20 weeks after starting administration (p < 0.0001). The medication was discontinued in four patients because of progression of primary disease, high cost, oral dryness, and anemia. No significant toxicity was observed on the serum biochemical analyses.

Conclusions

Nalfurafine hydrochloride contributed to long-term suppression of pruritus without significant safety problems.