Therapeutic effect of topical gamma-linolenic acid on refractory uremic pruritus

Metabolomic and lipidomic insights into the impact of Euglena gracilis-derived β-glucan supplementation on sow colostrum and milk composition

Euglena gracilis, an algae-derived source of β-glucan, exhibits prebiotic activity that enhances colostrum quality and improves growth, though the underlying mechanisms remain unclear. This study investigates the effects of E. gracilis supplementation during late gestation and lactation on sow colostrum and milk biomolecular profiles. Sixty-one crossbred sows (Landrace × Yorkshire) were assigned to a standard diet (CON; n = 30) or the CON diet supplemented with 1 g/sow/day of E. gracilis (TRT; n = 31) from day 85 of gestation until day 21 of lactation. Sow performance, including litter size and weight, was recorded from birth to day 21 of age. Colostrum samples (n = 20; 10 sows/group) were collected within 1 h of farrowing, and milk samples were collected from the same sows on days 3 and 10 of lactation to assess alterations in non-volatile polar metabolites (NVM), fatty acids (FA), and associated metabolic pathways. On average, the litter size at birth was 14.2 ± 2.5 piglets/litter, with no effect of dietary treatment from birth to day 21 of lactation (P > 0.05). However, piglets suckled by TRT sows tended to have higher average daily gain from birth to day 21 of age than those suckled CON sows (191.0 ± 6.7 vs. 173.6 ± 6.8 g/day, P = 0.073). Chemometric analysis revealed distinct NVM and FA profiles between the groups, particularly in the colostrum. Although E. gracilis supplementation influenced the contents of multiple metabolites, focus has been given to those that have direct impact on piglet development, including increased colostrum leucine (P = 0.001), threonine (P < 0.001), and N-acetylglucosamine (P = 0.002), enhancing colostrum quality and immunomodulatory potential. Elevated colostrum gamma-linolenic acid (P = 0.047) and arachidonic acid (P = 0.019) levels suggested enhanced immune development. Pathways associated with amino sugars and nucleotide sugars and glucose-related metabolism in colostrum were also modulated. These findings suggest E. gracilis-derived β-glucan as a potential dietary supplement for enhancing sow colostrum quality and piglet growth.

Identification and Management of CKD-Associated Pruritus: Current Insights

Chronic kidney disease-associated pruritus (CKD-aP) is a frequent and distressing problem for individuals with chronic kidney disease (CKD) and end-stage renal disease. It affects around 20% of those with CKD and 40% of those with end-stage renal disease. Despite its clear association with poorer psychosocial and medical outcomes, it is often underreported by patients and frequently remains unnoticed by healthcare providers. This is likely due to uncertainty regarding its diagnosis and treatment. Most commonly, CKD-aP could be screened with questionnaires like the KDQoL-36 and WI-NRS, chosen for their simplicity and ease of use. Prior treatment studies of CKD-aP were mostly limited by noncontrolled design and small sample size. First CKD-aP medication - difelikefalin a powerful, new therapeutic option was approved by Federal Drug Administration (FDA) in 2021 and European Medicines Agency (EMA) in 2022. Recent expert opinions, clinical trials and metanalysis identified difelikefalin and gabapentinoids as medications of choice in treatment of CKD-aP. All these findings improved current understanding and management of this condition.

Skin barrier: new therapeutic targets for chronic kidney disease-associated pruritus - a narrative review

The current incidence of chronic kidney disease-associated pruritus (CKD-aP) in patients with end-stage renal disease (ESRD) is approximately 70%, especially in those receiving dialysis, which negatively affects their work and private lives. The CKD-aP pathogenesis remains unclear, but uremic toxin accumulation, histamine release, and opioid imbalance have been suggested to lead to CKD-aP. Current therapeutic approaches, such as opioid receptor modulators, antihistamines, and ultraviolet B irradiation, are associated with some limitations and adverse effects. The skin barrier is the first defense in preventing external injury to the body. Patients with chronic kidney disease often experience itch due to the damaged skin barrier and reduced secretion of sweat and secretion from sebaceous glands. Surprisingly, skin barrier-repairing agents repair the skin barrier and inhibit the release of inflammatory cytokines, maintain skin immunity, and ameliorate the micro-inflammatory status of afferent nerve fibers. Here, we summarize the epidemiology, pathogenesis, and treatment status of CKD-aP and explore the possibility of skin barrier repair in CKD-aP treatment.

Eicosapentaenoic acid supplementation alleviates pruritus, enhances skin moisture, and mitigates depression in maintenance hemodialysis patients

Background

The objective of this study is to investigate the effects of oral supplementation with eicosapentaenoic acid (EPA) on circulating inflammatory factors, cardiometabolic parameters, skin moisturization, and the consequent symptoms of pruritus and depression in maintenance hemodialysis patients.

Materials and methods

A total of 60 maintenance hemodialysis patients with severe pruritus symptoms completed this randomized, placebo-controlled study. Subjects of treatment group (n = 30) were instructed to consume 1000 mg fish oil (>900 mg EPA) and subjects of placebo group (n = 30) were instructed to consume 1000 mg soybean oil twice daily for 3 months. 5-D pruritus scoring, the Beck Depression Inventory (BDI) scale, skin moisture, serum creatinine, inflammatory factors, and cardiometabolic parameters were examined at baseline, and at the first, second, and third month post-supplementation.

Results

A significantly decreased pruritus level was observed in the treatment group, whereas an opposite result was observed in the placebo group. Increased skin moisture levels on both the face and arms were observed in the treatment group, but not in the placebo group. Supplementation of EPA significantly decreased serum CRP and IL-6 levels. Significant decreases in total cholesterol (CHO), and triglycerides (TG) levels were observed; however, a decrease in high-density lipoprotein (HDL) level was observed in the treatment group. There was no change in plasma creatinine (CR) observed in both groups. A significantly decreased BDI score was observed, whereas the opposite result was observed in the placebo group. A correlational study showed that the severity of pruritus was significantly associated with skin moisture and serum CRP. The severity of pruritus was also positively correlated with the BDI score.

Conclusion

Supplementation of EPA may provide multiple benefits including alleviating pruritus symptoms, addressing skin dryness, and mitigating depression in maintenance hemodialysis patients.

Pathways for Diagnosing and Treating CKD-Associated Pruritus: A Narrative Review

Purpose of Review

Chronic kidney disease (CKD)-associated pruritus is a common, persistent, and distressing itch experienced by patients across the CKD spectrum. Although the disorder is associated with adverse outcomes and poor health-related quality of life, it remains underdiagnosed and undertreated. The purpose of this narrative review is to offer health care providers guidance on how to effectively identify, assess, and treat patients with CKD-associated pruritus, with the goal of reducing symptom burden and improving patient-important outcomes, such as quality of life (QoL).

Sources of Information

A panel of nephrologists and researchers from across Canada and the United States was assembled to develop this narrative review based on the best available data, current treatment guidelines, and their clinical experiences.

Methods

A panel of nephrologists who actively care for patients with pruritus receiving dialysis from across Canada was assembled. Two researchers from the United States were also included based on their expertise in the diagnosis and management of CKD-associated pruritus. Throughout Spring 2023, the panel met to discuss key topics in the identification, assessment, and management of CKD-associated pruritus. Panel members subsequently developed summaries of the pertinent information based on the best available data, current treatment guidelines, and added information on their own clinical experiences. In all cases, approval of the article was sought and achieved through discussion.

Key Findings

This narrative review provides pragmatic guidance addressing: (1) methods for screening CKD-associated pruritus, (2) assessing severity, (3) management of CKD-associated pruritus, and (4) suggested areas for future research. The panel developed a 3-pillar framework for proactive assessment and severity scoring in CKD-aP: systematic screening for CKD-associated pruritus (pillar 1), assessment of pruritus intensity (pillar 2), and understanding the impact of CKD-associated pruritus on the patient's QoL (pillar 3). Management of CKD-associated pruritus can include ensuring optimization of dialysis adequacy, achieving mineral metabolism targets (ie, calcium, phosphate, and parathyroid hormone). However, treatment of CKD-associated pruritus usually requires additional interventions. Patients, regardless of CKD-associated pruritus severity, should be counseled on adequate skin hydration and other non-pharmacological strategies to reduce pruritus. Antihistamines should be avoided in favor of evidence-based treatments, such as difelikefalin and gabapentin.

Limitations

A formal systematic review (SR) of the literature was not undertaken, although published SRs were reviewed. The possibility for bias based on the experts' own clinical experiences may have occurred. Key takeaways are based on the current available evidence, of which head-to-head clinical trials are lacking.

Funding

This work was funded by an arm's length grant from Otsuka Canada Pharmaceutical Inc. (the importer and distributer of difelikefalin in Canada). LiV Medical Education Agency Inc. provided logistical and editorial support.

Chronic kidney disease-associated pruritus in patients undergoing hemodialysis: Xerosis and topical therapy

Chronic kidney disease-associated pruritus (CKD-aP) is a common and distressing symptom for patients with CKD and a difficult challenge for nephrologists and dermatologists. Recent results showed the multifactorial nature of the pathophysiology, and therapeutic trials were only successful in certain subsets of patients. The clinical manifestations are varied, with xerosis being the most common dermatological manifestation and correlated with the intensity of CKD-aP. A better understanding of the pathophysiology of xerosis in CKD-aP and appropriate topical treatment could correct xerosis to reduce the intensity of CKD-aP and improve the patient's quality of life.

Uremic pruritus: pathophysiology, clinical presentation, and treatments

Uremic pruritus is one of the most common and bothersome symptoms in patients with end-stage renal disease. Most patients with uremic pruritus experience a prolonged and relapsing course and significant impairments of quality of life. The pathophysiology of uremic pruritus is not completely understood. A complex interplay among cutaneous biology and the nervous and immune systems has been implicated, with the involvement of various inflammatory mediators, neurotransmitters, and opioids. Uremic pruritus treatment outcomes are often unsatisfactory. Clinical trials have mostly been small in scale and have reported inconsistent results. Recent evidence shows that gabapentinoids, nalfurafine, and difelikefalin are effective for relieving uremic pruritus in hemodialysis patients. This review provides an overview of the epidemiology and proposed mechanisms of uremic pruritus, then highlights the manifestations of and clinical approach to uremic pruritus. Current evidence regarding treatment options, including topical treatments, treatment of underlying disease, phototherapy, and systemic treatments, is also outlined. With a better understanding of uremic pruritus, more therapeutic options can be expected in the near future.

Nouvelles thérapies dans la prise en charge du patient avec maladie rénale chronique souffrant de prurit : une revue de la littérature New therapies in the management of chronic kidney disease associated pruritus

Chronic Kidney Disease associated Pruritus (CKD-aP) is a well-established and frequent complication observed in patient with CKD, especially in dialysis patients. However, the management of CKD-aP remains a challenge as the pathophysiology and research studies are too small. Finally, there are a few proposed treatment options with significant clinical benefits. This general review will summarize all the available treatments for the CKD-aP and will highlight the clinical efficacy and limits of the current drugs. Notably, we will focus on the implication of the opioid receptor in the pathophysiology of the CKD-aP and the recently Kappa opioid receptor agonist. © 2022 Published by Elsevier Masson SAS on behalf of Société francophone de néphrologie, dialyse et transplantation.

Omega-3 Fatty Acids Improve Chronic Kidney Disease-Associated Pruritus and Inflammation

Background and Objectives: Chronic kidney disease-associated pruritus (CKD-aP) is a common symptom in hemodialysis patients. A frequent and intense itching sensation largely torments patients, impacts quality of life outcomes, and it has an independent association with mortality. The objective of this study is to investigate the effects of oral supplementation with omega-3 polyunsaturated fatty acid (omega-3 PUFA) on circulating interleukin-6 (IL-6), cardiometabolic parameters, skin moisturization, and the consequent symptoms of pruritus in hemodialysis patients. Materials and Methods: Volunteers on maintenance hemodialysis with very severe pruritus symptoms were enrolled in this prospective cohort study. Subjects were instructed to consume 1000 mg fish oil once daily for 3 months. Pruritus scoring, skin moisture, plasma IL-6, and cardiometabolic parameters were measured at baseline, and at the first, second, and third month post-supplementation with fish oil for assessment of the clinical significance. Results: A total of 27 patients who had a mean age of 67.33 ± 11.06 years and 3.98 ± 3.23 years on hemodialysis completed the study. Supplementation with omega-3 PUFA significantly decreased IL-6 levels (p < 0.001), but increased the levels of c-reactive protein (CRP) (p < 0.05). Evaluation of the cardiovascular risk showed significant (all p < 0.001) decreases in the total cholesterol (CHO), low-density lipoprotein (LDL), and triglycerides (TG) levels, and an increase in the high-density lipoprotein (HDL) level. A significant decrease in plasma creatinine (CR) was observed (p < 0.001), but the decrease was limited. Supplementation with omega-3 PUFA significantly improved (all p < 0.001) skin hydration on both the face and arms, as well as disease-related symptoms of pruritus. Conclusion: Omega-3 PUFA supplementation improved inflammation, renal function, cardiovascular parameters, dry skin conditions, and the consequent symptoms of pruritus in hemodialysis patients.

Uremic Pruritus: From Diagnosis to Treatment

Uremic pruritus, or chronic kidney disease-associated pruritus, is common, bothersome, and sometimes debilitating in patients with chronic kidney disease or end-stage renal disease. Due to its variable clinical manifestations, the diagnosis of uremic pruritus requires exquisite evaluation. Excluding itch resulting from other dermatological causes as well as other systemic conditions is essential for a proper diagnosis. The pathophysiology of uremic pruritus remains uncertain. Hypotheses including toxin deposition, immune system dysregulation, peripheral neuropathy, and opioid imbalance are supposed. This review summarizes the way to accurately diagnose uremic pruritus and describes the latest treatment options.

Chronic Intractable Pruritus in Chronic Kidney Disease Patients: Prevalence, Impact, and Management Challenges - A Narrative Review

Chronic kidney disease (CKD) is recognized as a leading public health problem and causes numerous health complications. One of the most common and burdensome dermatological symptoms affecting patients undergoing dialysis is CKD-associated pruritus (CKD-aP). This condition not only has a negative impact on sleep, mood, daily activities, and quality of life but also increases the mortality risk of hemodialyzed patients. Despite that, this condition is greatly underestimated in clinical practice. Due to the complex and still not fully understood etiopathogenesis of CKD-aP, the choice of an effective therapy remains a challenge for clinicians. Most common therapeutic algorithms use topical treatment, phototherapy, and various systemic approaches. This review aimed to summarize most recent theories about the pathogenesis, clinical features, and treatment of CKD-aP.

Western and complementary alternative medicine treatment of uremic pruritus: A literature review

Uremic pruritus (UP), also called chronic kidney disease-associated pruritus (CKD-aP), is a bothersome symptom that causes sleep disturbance, anxiety, depression, and reduced quality of life. Pruritus often occurs in patients with end-stage renal disease. There is still no definite treatment for UP due to its unclear pathogenesis. We searched electronic databases (PubMed and Google Scholar) and gathered the latest clinical trials and pilot studies of Western and complementary alternative medicine (CAM) therapies for UP in English. These UP studies were separated into three main groups: systemic, topical, and others and CAM. Gabapentin, nalfurafine, acupuncture, and Chinese herbal bath therapy (CHBT) show antipruritic effects, with higher evidence grades in the meta-analysis. Emollients with additive compounds are more effective for reducing itch than emollients without additives. Supplements for deficient elements, such as zinc, omega-3, and omega-6, also show benefits for pruritus improvement. CAM therapies such as acupuncture, herbs, and herbal baths or creams all have good results for UP treatment. We summarize the treatments and suggest a treatment algorithm for UP according to severity. Some UP therapies are already supported by large-scale clinical evidence, and some new treatments can provide patients with new hope and treatment options. However, these new methods still need large population studies and further exploration.

Chronic Kidney Disease-Associated Pruritus: A Review

BACKGROUND

Chronic kidney disease-associated pruritus (CKD-aP), also known as uraemic pruritus, is a disabling symptom for patients and a challenging condition for clinicians. Despite being common amongst end-stage kidney disease (ESKD) patients, it remains underestimated and underdiagnosed. The exact pathogenesis remains largely elusive, which hampers the synthesis of a definite treatment approach.

SUMMARY

Chronic pruritus (lasting 6 weeks or more in duration) is a common and potentially disabling symptom in patients with advanced CKD. A unified hypothesis of pathogenesis has not yet been concluded. Studies have shown changes in the immunochemical milieu of the skin in patients with CKD-aP with several inciting stimuli identified. However, other unrecognized factors are likely to be involved. This article will review the current observations and understanding of the postulated pathogenesis of CKD-aP, as well as the evidence for current management strategies. Key Messages: CKD-aP is a common and troubling symptom amongst ESKD patients that is associated with decreased quality of life and poor prognosis. Its exact pathogenesis, at the time of writing, is not well-understood. A stepwise approach is recommended for management. Systematic reviews show the largest body of evidence was found for the effectiveness of gabapentin. Comparison is needed between newly emerging pharmacological agents such as kappa-opioid receptor agonists and more established agents, such as the gabapentinoids. Finally, renal transplantation should be considered in severe and refractory cases who are suitable transplant candidates as it has shown an excellent outcome in most cases.

Systemic causes of non-dermatologic chronic pruritus in the pediatric population and their management: An unexplored area

Chronic pruritus associated with systemic diseases in the pediatric population has been infrequently addressed in the literature. This review focuses on chronic pruritus presenting without cutaneous manifestations. Common systemic etiologies include diseases with hepatic, renal, and hematologic origins. This encompasses several congenital liver disorders, end-stage renal disease (ESRD), and lymphoproliferative disorders such as Hodgkin's lymphoma. In this paper, an expert panel describes the clinical characteristics, pathophysiology, and therapeutic treatment ladders for chronic pruritus associated with the aforementioned systemic etiologies. Novel therapies are also reviewed. Our aim is to shed light on this unexplored area of pediatric dermatology and instigate further research.

Chronic Kidney Disease-Associated Pruritus

Pruritus is a distressing condition associated with end-stage renal disease (ESRD), advanced chronic kidney disease (CKD), as well as maintenance dialysis and adversely affects the quality of life (QOL) of these patients. It has been reported to range from 20% to as high as 90%. The mechanism of CKD-associated pruritus (CKD-aP) has not been clearly identified, and many theories have been proposed to explain it. Many risk factors have been found to be associated with CKD-aP. The pruritus in CKD presents with diverse clinical features, and there are no set features to diagnose it.The patients with CKD-aP are mainly treated by nephrologists, primary care doctors, and dermatologists. Many treatments have been tried but nothing has been effective. The search of literature included peer-reviewed articles, including clinical trials and scientific reviews. Literature was identified through March 2021, and references of respective articles and only articles published in the English language were included.

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.

Interventions for itch in people with advanced chronic kidney disease

BACKGROUND

Itch in patients with chronic kidney disease (CKD) is common, often very distressing and associated with depression, reduced quality of life, and increased death. The most common first-line treatment has been the use of antihistamines despite the lack of substantial evidence for its use for uraemic itch. Few recommendations and guidelines exist for treatment.

OBJECTIVES

We aimed to determine: 1) the benefits and harms (both absolute and relative) of all topical and systemic interventions for the treatment of uraemic itch, either alone or in combination, when compared with placebo or standard care; and, 2) the dose strength or frequency, stage of kidney disease or method of dialysis used (where applicable) in cases where the effects of these interventions vary depending on co-interventions.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 17 December 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in adults with CKD stages 4 or 5 comparing treatments (pharmacological, topical, exposure, dialysis modality) for CKD associated itch to either placebo or other established treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted study data and assessed study quality. Data were analysed using a random effects meta-analysis design estimating the relative effects of treatment versus placebo. Estimates of the relative effects between treatments are included where possible. For continuous measures of severity of itch up to three months, mean difference (MD) or standardised mean difference (SMD) were used. When reported, adverse effects were tabulated. The certainty of the evidence was estimated using GRADE.

MAIN RESULTS

Ninety-two RCTs, randomising 4466 participants were included. Fifty-eight studies (3285 participants) provided sufficient data to be meta-analysed. Of these, 30 compared an intervention to a placebo or control. The 10 cm Visual Analogue Scale (VAS) was the dominant instrument utilized for itch reporting and the Duo score was used in a minority of studies. GABA analogues including, gabapentin and pregabalin, reduce itch in patients with CKD (5 studies, 297 participants: 4.95 cm reduction, 95% CI 5.46 to 4.44 lower in VAS compared to placebo; high certainty evidence). Kappa opioid agonists, including nalfurafine also reduced itch in this population (6 studies, 661 participants: 1.05 cm reduction, 95% CI 1.40 to 0.71 lower in VAS compared to placebo; high certainty evidence). Ondansetron had little or no effect on itch scores (3 studies, 183 participants: 0.38 cm reduction, 95% CI 1.04 lower to 0.29 higher in VAS compared to placebo; high certainty evidence). Reduction in the severity of itch was reported with oral montelukast, turmeric, zinc sulfate and topical capsaicin. For all other interventions, the certainty of the evidence was low to moderate, and the interventions had uncertain effects on uraemic pruritus. Six studies have disclosed significant financial support from their respective manufacturers, six were affected by lack of blinding, and 11 studies have 15 participants or less. Older, smaller RCTs often failed to follow intention-to-treat protocols with unexplained dropouts after randomisation. Adverse effects were generally poorly and inconsistently reported across all RCTs. No severe adverse events were reported for any intervention.

AUTHORS' CONCLUSIONS

The RCTs of this meta-analysis contain a large array of interventions with a diverse set of comparators. For many interventions, trials are sparse. This served to make informative meta-analysis challenging. Of all treatments for uraemic pruritus, gabapentinoids (gabapentin and pregabalin) were the most studied and show the greatest reduction in itch scores. Further RCTs, even of the scale of the largest trials included in this review, are unlikely to significantly change this finding. Kappa-opioid agonists (mainly nalfurafine) also may reduce itch, but indirect comparison suggests a much more modest effect in comparison to GABA analogues. Evidence for oral montelukast, turmeric, zinc sulfate, and topical capsaicin also showed an itch score reduction. However, these reductions were reported in small studies, and warrant further investigation. Ondansetron did not reduce itch. It is somewhat unlikely that a further study of ondansetron will change this result.

Complementary and alternative medicine therapies for uremic pruritus - A systematic review of randomized controlled trials

INTRODUCTION

Uremic pruritus (UP) is one of the most bothersome symptoms among chronic kidney disease (CKD) patients. The pathophysiology of UP remains elusive, resulting in limited treatment options. The inability of standard medical treatments to provide effective relief has piqued interest in complementary and alternative medicine (CAM).

METHODOLOGY

A systematic review of randomized controlled trials (RCTs) summarizing the efficacy and safety profile of CAM used for UP in CKD patients was performed. CAM interventions were classified using categories proposed by the National Center for Complementary and Integrative Health. The efficacy of each CAM was determined from changes in UP severity and all reported adverse effects were extracted.

RESULTS

Of 5242 articles screened, 34 RCTs were included, with 15 (44.1 %) studies having a sample size greater than 50. The studies considered 21 treatments including omega-3 fatty acid supplementation (n=5), acupuncture (n=5), topical capsaicin (n=4) and acupressure (n=3). Acupuncture, acupressure and topical capsaicin were shown to be effective in improving uremic pruritus. Interventions which include oral omega-3 fatty acid and zinc supplementation demonstrated mixed efficacy. Other therapies such as evening primrose oil, turmeric, vitamin B3, vitamin D and thermal therapy were not effective for treatment of UP. Common adverse effects reported with topical capsaicin included mild burning sensations (50.0-88.2 %) or erythema (6.7-22.7%) while that of acupuncture included soreness (7.5 %), bleeding (6.0-7.5%) and hematoma (1.9 %).

CONCLUSIONS

Acupuncture, acupressure and topical capsaicin have the largest body of evidence for efficacy in the treatment of UP. Larger and higher quality RCTs are required to examine the efficacy and safety of promising CAM.

Uremic solutes of indoxyl sulfate and p-cresol enhance protease-activated receptor-2 expression in vitro and in vivo in keratinocytes

OBJECTIVES

Uremic pruritus is common in patients with chronic kidney disease (CKD). The retention of uremic solutes is thought to be associated with uremic pruritus. Meanwhile, activation of protease-activated receptor-2 (PAR-2) has been suggested to play an important role in pruritus. The present study was performed to investigate the effects of uremic solutes on the expression of PAR-2 in the skin.

METHODS

Indoxyl sulfate (IS), p-cresol (PC), and uremic sera from CKD patients were used to stimulate PAR-2 expression in normal human epidermal keratinocytes (NHEKs). Also, NHEKs were additionally pretreated with soybean trypsin inhibitor to evaluate its inhibitory effect on PAR-2 expression. Patterns of cutaneous PAR-2 expression were investigated in skin samples from five CKD patients and CKD mice.

RESULTS

In NHEKs, IS, PC, and sera from CKD patients significantly induced PAR-2 mRNA and protein expression. Soybean trypsin inhibitor significantly decreased PAR-2 mRNA and protein expression in NHEKs treated with IS, PC, and CKD sera. NHEKs treated with IS and PC exhibited significant increases in protease activity. Skin from both CKD patients and mice exhibited marked upregulation of PAR-2 expression compared to control skin.

CONCLUSIONS

Results from the present study suggest that uremic solutes either directly or indirectly affect PAR-2 expression in the skin of CKD subjects, potentially playing an important role in the pathogenesis of uremic pruritus.

The Effect of Ostrich Oil as a Complementary Medicine on the Severity of Pruritus and Quality of Life in Hemodialysis Patients

INTRODUCTION

Pruritus is one of the most common problems in a uremic syndrome that reduces the quality of life due to the constant unpleasant feeling. The purpose of this study was to investigate the effect of ostrich oil massage on the severity of pruritus and quality of life in hemodialysis patients.

METHODS

In this study, 68 hemodialysis patients with pruritus were selected based on the available sampling method. The intervention group used 1 mL ostrich oil on the pruritus area for 10 min each night for 1 month. The control group received a placebo massage. Pruritus severity questionnaire-based itch severity scale and quality of life questionnaire were completed, respectively, at the end of each week and at the end of the period. Statistical analysis was done using SPSS software version 23 and applying on independent t test, paired t test, and analysis of covariance.

RESULTS

During the first and second weeks after the treatment, there was no statistical difference between the mean scores of pruritus severity in both groups (p > 0.05); however, in the third and fourth weeks after the treatment, the mean severity level of pruritus in the ostrich oil group was lower than in the placebo group, and these differences were statistically significant between the two groups (p < 0.05). There was no significant difference in quality of life between two groups of ostrich and placebo.

CONCLUSION

The use of ostrich oil was effective in reducing pruritus in hemodialysis patients. This method can be proposed as a complementary method for relieving pruritus in hemodialysis patients.

HYVIA™: A novel, topical chia seed extract that improves skin hydration

BACKGROUND

Chia seeds have gained importance as it is the highest known plant source of omega-3 (ω3) polyunsaturated fatty acids. Specifically, chia seeds possess ω3 α-linolenic acid (ALA) and ω6 linoleic acid (LA), together known as Vitamin F, which play an important role in maintaining skin function. Protein phosphatase 2A (PP2A) is a master regulatory protein that plays a critical role in skin barrier function and its activity is modulated by natural lipids.

AIMS

Obtain a chia seed extract (HYVIA™) with significant higher levels of Vitamin F, determine in vitro PP2A activity and skin hydration markers compared to other commercial chia seed extracts (CCSEs), and evaluate the potential skin hydration benefits clinically in human subjects.

METHODS

A PP2A demethylation assay was utilized to assess PP2A activity. In vitro studies utilizing normal human epidermal keratinocytes (NHEKs) were treated with HYVIA™ and gene expression of hydration markers (AQP3, HAS2) were measured by quantitative PCR (qPCR). A 16-subject clinical trial was performed with 0.1% HYVIA™ formulated in a cream and applied topically to assess its skin moisturizing potential.

RESULTS

We demonstrate here that HYVIA™, ALA, and LA inhibit PP2A demethylation, boosting PP2A activity, while most other CCSEs do not. Unlike other CCSEs, HYVIA™ increases keratinocyte hydration factors aquaporin-3 and hyaluronic acid synthase-2 in vitro. Clinical assessment of 0.1% HYVIA™ cream shows that HYVIA™ improves skin hydration.

CONCLUSIONS

HYVIA™ is a novel chia seed extract, enriched for Vitamin F, that modulates PP2A activity and clinically improves skin hydration and barrier function.

CKD-Associated Pruritus: New Insights Into Diagnosis, Pathogenesis, and Management

Chronic kidney disease–associated pruritus (CKD-aP) is a common, troubling and in some cases debilitating problem for patients with CKD and end-stage renal disease. Despite a prevalence rate of approximately 20% in CKD and 40% in end-stage renal disease, and a clear association with poorer psychosocial and medical outcomes, this condition is often underreported by patients and overlooked by health care providers. This is likely due, in part, to uncertainty regarding its pathogenesis and treatment. Most commonly, CKD-aP is attributed to toxin build-up, peripheral neuropathy, immune system dysregulation, or opioid dysregulation. Prior treatment studies of CKD-aP have targeted these potential etiologies but have been limited by noncontrolled design, small sample size, and non-uniform definitions of CKD-aP. Recently, several large, randomized controlled trials targeting opioid dysregulation have yielded promising results. These trials have spurred new hope for understanding and treating this condition.

Randomized controlled trial of medium cut-off versus high-flux dialyzers on quality of life outcomes in maintenance hemodialysis patients

Medium cut-off (MCO) dialyzers help remove larger middle molecules associated with symptoms related to the accumulation of uremic retention solutes. We investigated the effect of an MCO dialyzer on the improvement of quality of life (QOL) in maintenance hemodialysis (HD) patients. Forty-nine HD patients with high-flux dialysis were randomly assigned to either an MCO (Theranova 400, Baxter) or a high-flux (FX CorDiax 80 or 60, Fresenius Medical Care) dialyzer and completed the study. QOL was assessed at baseline and after 12 weeks of treatment using the Kidney Disease Quality of Life Short Form-36, and pruritus was assessed using a questionnaire and visual analog scale. The reduction ratios of middle molecules were also evaluated. Laboratory markers, including serum albumin, did not differ between the two groups after 12 weeks. Removals of kappa and lambda free light chains were greater for MCO dialyzer than high-flux dialyzer. The MCO group had higher scores than the high-flux group in the domains of physical functioning and physical role (75.2 ± 20.8 vs. 59.8 ± 30.1, P = 0.042; 61.5 ± 37.6 vs. 39.0 ± 39.6, P = 0.047, respectively), and the MCO group had lower mean scores for morning pruritus distribution and the frequency of scratching during sleep (1.29 ± 0.46 vs. 1.64 ± 0.64, P = 0.034; 0.25 ± 0.53 vs. 1.00 ± 1.47, P = 0.023, respectively). MCO dialyzers may improve patient-reported outcomes, particularly the physical components of QOL and uremic pruritus, in patients with high-flux dialyzers.

Itching as the onset of pain (part 2)

Itching of the skin is a particularly unpleasant subjective sensation that causes the need to scratch. Physiological itching occurs in response to environmental irritants (friction, insect crawling, temperature changes, etc.) and disappears after elimination of the cause. Pathological itching is caused by changes in the skin or throughout the body and causes a strong need to get rid of itching by combing or any other method. Itching is a common symptom of local (dermatological) or general (systemic) disease. It can be limited (localized) or diffuse (generalized).One of the causes of itching is often noted endocrine diseases and metabolic disorders: hyper- and hypofunction of the thyroid gland, diabetes mellitus and hyperparathyroidism. In thyroid hyperfunction, generalized (inconstant and little-pronounced) itching of the skin is observed in the clinical picture only in 10 % of patients. It is accepted that itching of the skin in thyrotoxicosis syndrome is due to increased activity of kinin in combination with an increase in major metabolism and an increase in body and skin temperature (123).Itching caused by impaired bile secretion is characteristic of many diseases of the liver: primary biliary cirrhosis, sclerosing cholangitis, viral hepatitis caused by cholestasis medications and other causes of obstructive jaundice. It is in these cases that prurigo is usually generalized, but in some typical cases it is more pronounced on the feet and palms. With this pathology, itching is caused by obstruction of the biliary tract, however, and to this day, no close correlation has been found between serum bilirubin and the severity of itching.If it was previously thought that itching in pathology of the peripheral or central nervous system, such as multiple sclerosis, neuropathy, compression or irritation of nerves (e.g., paraesthetic dorsalgia, brachioradial itching) is also a significant symptom, then modern studies prove that in more cases, itching is not characteristic of most pathologies of the nervous system, so after a detailed anamnesis, examination and initial research, the patient should be referred to a related specialist, except in cases of about obvious postherpetic neuropathy, painless paresthesia, or brachioradial itching, which can often be guided in the provision of primary care.Instead, there are some psychological conditions and a number of psychiatric illnesses (obsessive-compulsive disorders, depression, and parasite illusions) that are most commonly diagnosed with the exclusion method. Neurotic squabbles are scattered on the body of the excorii, covered with scales that may occur in any area of the body that the patient may reach, but are often limited by limbs.

[Pruritus in systemic diseases : Common and rare etiologies]

Chronic pruritus is a symptom of various internal disorders. In contrast to dermatological diseases, pruritus does not present with primary skin alterations in these patients. However, intense scratching my cause secondary skin changes such as abrasion, excoriation, prurigo nodularis, or in rare cases even scarring. The most common internal causes for chronic pruritus are chronic kidney disease, hepatobiliary, and hematological disorders as well as adverse drug reactions. Pruritus is less commonly seen in patients with endocrine or metabolic diseases, malabsorption syndromes, infectious diseases, and solid tumors. The pathogenesis of pruritus in these disorders remains largely elusive, albeit first insights have been gained for uremic and cholestatic pruritus. Antipruritic treatment is therefore symptomatic in most cases and may represent a clinical challenge. The calcium channel blockers gabapentin and pregabalin have the best proven efficacy in chronic kidney disease associated pruritus. In Japan, nalfurafine, a κ-opioid receptor agonist, has been licensed for this indication. UVB light may also attenuate uremic symptoms. In patients suffering from hepatobiliary disorders the sequestrant cholestyramine and the enzyme inducer rifampicin are effective. Furthermore, bezafibrate, the μ‑opioid receptor antagonists and, in Japan, nalfurafine may be used to ameliorate cholestatic pruritus. So far, no randomized controlled trials have been performed for chronic itch in other internal disorders. Antipruritic treatment is symptom-based with a focus on the effective therapy of the underlying disease.

Pruritus Associated With Chronic Kidney Disease: A Comprehensive Literature Review

The prevalence of pruritus in chronic kidney disease (CKD) patients has varied over the years, and some studies suggest the prevalence may be coming down with more effective dialysis. Chronic kidney disease-associated pruritus (CKD-aP), previously called uremic pruritus, is a distressing symptom experienced by patients with mainly advanced chronic kidney disease. CKD-aP is associated with poor quality of life, depression, anxiety, sleep disturbance, and increased mortality. The incidence of CKD-aP is decreasing given improvements in dialysis treatments, but approximately 40% of patients with end-stage renal disease experience CKD-aP. While the pathogenesis of CKD-aP is not well understood, the interaction between non-myelinated C fibers and dermal mast cells plays an important role in precipitation and sensory stimulation. Other causes of CKD-aP include metabolic abnormalities such as abnormal serum calcium, parathyroid, and phosphate levels; an imbalance in opiate receptors is also an important factor. CKD-aP usually presents as large symmetric reddened areas of skin, often at night. Managing CKD-aP is a challenge. Research in this area is difficult because most studies are not comparable given their small group samples, study designs, and lack of standardized study measures. The most commonly used treatment is a combination of narrow-band ultraviolet B phototherapy and a μ-opioid receptor antagonist such as naltrexone.

Current treatment strategies in refractory chronic pruritus

Chronic pruritus is a highly prevalent, debilitating disease, which is often refractory to conventional therapies. A step-wise, guideline-driven approach should be adopted in the management of these patients. Emollients as well as topical corticosteroids if appropriate should be initiated whilst looking for the cause underlying the pruritus. If these measures fail, and the origin of the pruritus remains unknown, cannot be treated or does not respond to therapy, systemic therapies as for example gabapentinoids, antidepressants, mu-opioid-receptor antagonists or, in case of inflammatory conditions, immunosuppressive drugs should be recommended. Novel agents, especially systemic monoclonal antibodies, neurokinin-1 receptor antagonists and opioid receptor modulators, are promising in providing relief in refractory cases.

Dermatologic manifestations in end stage renal disease

Skin manifestations are commonly seen in end stage renal disease (ESRD). Skin involvement in this population can be extensive and dramatically worsen quality of life. Close observation of the skin and nails of ESRD patients by clinicians allows for timely diagnosis and treatment, which ultimately improves quality of life and reduces mortality. In this article we focus on the cutaneous changes most commonly seen in ESRD patients. PubMed/Medline database search was done for published literature on skin manifestations in ESRD patients. All the available literature was reviewed and relevant articles were used to discuss about clinical features, pathogenesis, histology and treatment of each skin disorder in ESRD patients. Most commonly encountered skin manifestations in patients with ESRD are pruritus, xerosis, pigmentation changes, nail changes, perforating disorders, calcifying disorders, bullous dermatoses and nephrogenic systemic fibrosis. Skin manifestations in ESRD can be difficult to treat and multiple comorbidities in this patient population can exacerbate these disorders. Many of the treatment options are experimental with evidence largely derived from the case reports and small clinical trials. More large-scale trials are needed to firmly establish evidence based treatment guidelines. Prompt evaluation and management of these disorders improve morbidity and quality of life in ESRD patients.

Treatments of uremic pruritus: A systematic review

Till now many treatments attempted to relieve uremic pruritus (UP) though none of them are definite treatment. In this study, we gathered all studies conducted on UP treatment since 2000-2016. We conducted a systematic review by searching the electronic databases (PubMed, Scopus, and Google scholar). Patients were with chronic kidney disease who complained of UP. Clinical trials and pilot studies in English and Persian which were done on patients with ESRD who complained of itching between 2000 till 2016 were gathered. A total of 166 articles were collected. After excluding articles 41 articles were remaining. Then UP treatments classified into two main groups: Medical (chemical and herbal medicine) and non-medical. Most studies measured UP by VAS scoring system in which patients described the severity. This scoring system is individual dependent. There are lots of studies on UP treatment though there are lots of controversies in studies. Finding a definite cure for this unpleasant symptom can improve patients' quality of life. Conducting further studies for each treatment on larger population is essential to improve quality of life among the end stage renal disease patients.

The efficacy of a pseudo-ceramide and eucalyptus extract containing lotion on dry scalp skin

Objective

Dry and scaly conditions on the scalp are often observed in patients with atopic dermatitis, seborrheic dermatitis and/or pityriasis capitis. Those scalp lesions often exhibit low barrier function and reduced ceramide levels. Therefore, a clinical study was conducted to evaluate the efficacy of topical application of a pseudo-ceramide and eucalyptus extract-containing lotion on the scalps of patients with skin diseases.

Methods

Thirty-four subjects participated in this study (atopic dermatitis: 19 subjects; seborrheic dermatitis: 6 subjects; pityriasis capitis: 9 subjects). After 4 weeks of daily treatment with a pseudo-ceramide and eucalyptus extract-containing lotion, the skin symptoms had significantly improved in all patients with those skin diseases.

Results

Skin dryness, scaling, and erythema were significantly improved by treatment with the lotion. The moisture-retention ability of the scalp was significantly increased and itchiness, evaluated using a visual analog scale, decreased significantly. Accompanying those improvements was a significant improvement in the quality of life of the subjects, evaluated by the Skindex-16^®.

Conclusion

From these results, we conclude that this pseudo-ceramide and eucalyptus extract-containing lotion effectively improved the dry and scaly conditions of the scalp as well as the quality of life of subjects with atopic dermatitis, seborrheic dermatitis, or pityriasis capitis.

Treatment of Uremic Pruritus: A Systematic Review

BACKGROUND

Uremic pruritus is a common and burdensome symptom afflicting patients with advanced chronic kidney disease (CKD) and has been declared a priority for CKD research by patients. The optimal treatments for uremic pruritus are not well defined.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Adult patients with advanced CKD (stage ≥ 3) or receiving any form of dialysis.

SELECTION CRITERIA FOR STUDIES

PubMed, CINAHL, Embase, International Pharmaceutical Abstracts, Scopus, Cochrane Library, and ClinicalTrials.gov from their inception to March 6, 2017, were systematically searched for randomized controlled trials (RCTs) of uremic pruritus treatments in patients with advanced CKD (stage ≥ 3) or receiving any form of dialysis. 2 reviewers extracted data independently. Risk of bias was assessed using the Cochrane Collaboration risk-of-bias tool.

INTERVENTION

Any intervention for the treatment of uremic pruritus was included.

OUTCOMES

A quantitative change in pruritus intensity on a visual analogue, verbal rating, or numerical rating scale.

RESULTS

44 RCTs examining 39 different treatments were included in the review. These treatments included gabapentin, pregabalin, mast cell stabilizers, phototherapy, hemodialysis modifications, and multiple other systemic and topical treatments. The largest body of evidence was found for the effectiveness of gabapentin. Due to the limited number of trials for the other treatments included, we are unable to comment on their efficacy. Risk of bias in most studies was high.

LIMITATIONS

Heterogeneity in design, treatments, and outcome measures rendered comparisons difficult and precluded meta-analysis.

CONCLUSIONS

Despite the acknowledged importance of uremic pruritus to patients, with the exception of gabapentin, the current evidence for treatments is weak. Large, simple, rigorous, multiarm RCTs of promising therapies are urgently needed.

Blood lead level is a positive predictor of uremic pruritus in patients undergoing hemodialysis

Although uremic pruritus (UP) is a common and annoying symptom for end-stage renal disease patients on hemodialysis (HD) and peritoneal dialysis, its pathogenesis is poorly understood. However, systemic inflammation is one of the possible pathogenesis of UP, and blood lead level (BLL) has been noted to be associated with inflammation and nutritional status in long-term HD patients. There might be an interaction or association, therefore, between BLL and UP through systemic inflammation. We analyzed cross-sectional data among 866 participants. All of the 866 patients in this study were stratified into groups with low-normal (<10 μg/dL), high-normal (10-20 μg/dL), and abnormal BLLs (>20 μg/dL). The associations between UP and BLL and the clinical data were analyzed. Multivariate logistic regression demonstrated that HD duration, non-anuria, log ferritin, serum low-density lipoprotein, log BLL, high-normal BLL, and high BLL were associated with UP. In conclusion, BLL was positively associated with UP.

Development of a multidimensional assessment tool for uraemic pruritus: Uraemic Pruritus in Dialysis Patients (UP-Dial)

BACKGROUND

Dialysis patients with uraemic pruritus (UP) have significantly impaired quality of life. To assess the therapeutic effect of UP treatments, a well-validated comprehensive and multidimensional instrument needed to be established.

OBJECTIVES

To develop and validate a multidimensional scale assessing UP in patients on dialysis: the Uraemic Pruritus in Dialysis Patients (UP-Dial).

METHODS

The development and validation of the UP-Dial instrument were conducted in four phases: (i) item generation, (ii) development of a pilot questionnaire, (iii) refinement of the questionnaire with patient recruitment and (iv) psychometric validation. Participants completed the UP-Dial, the visual analogue scale (VAS) of UP, the Dermatology Life Quality Index (DLQI), the Kidney Disease Quality of Life-36 (KDQOL-36), the Pittsburgh Sleep Quality Index (PSQI) and the Beck Depression Inventory (BDI) between 15 May 2012 and 30 November 2015.

RESULTS

The 27-item pilot UP-Dial was generated, with 168 participants completing the pilot scale. After factor analysis was performed, the final 14-item UP-Dial encompassed three domains: signs and symptoms, psychosocial, and sleep. Face and content validity were satisfied through the item generation process and expert review. Psychometric analysis demonstrated that the UP-Dial had good convergent and discriminant validity. The UP-Dial was significantly correlated [Spearman rank coefficient, 95% confidence interval (CI)] with the VAS-UP (0·76, 0·69-0·83), DLQI (0·78, 0·71-0·85), KDQOL-36 (-0·86, -0·91 to -0·81), PSQI (0·85, 0·80-0·89) and BDI (0·70, 0·61-0·79). The UP-Dial revealed excellent internal consistency (Cronbach's α 0·90, 95% CI 0·87-0·92) and reproducibility (intraclass correlation 0·95, 95% CI 0·90-0·98).

CONCLUSIONS

The UP-Dial is valid and reliable for assessing UP among patients on dialysis. Future research should focus on the cross-cultural adaptation and translation of the scale to other languages.

[Pruritus in systemic diseases : Common and rare etiologies]

Chronic pruritus is a symptom of various internal disorders. In contrast to dermatological diseases, pruritus does not present with primary skin alterations in these patients. However, intense scratching may cause secondary skin changes such as abrasion, excoriation, prurigo nodularis, or in rare cases even scaring. The most common internal medicine causes for chronic pruritus are chronic kidney disease, hepatobiliary and hematological disorders as well as adverse drug reactions. Pruritus is less commonly seen in patients with endocrine or metabolic diseases, malabsorption syndromes, infectious diseases and solid tumors. The pathogenesis of pruritus in these disorders remains largely elusive, albeit preliminary insights have been gained for uremic and cholestatic pruritus. Antipruritic treatment is therefore symptomatic in most cases and may represent a clinical challenge. The calcium channel blockers gabapentin and pregabalin have the best proven efficacy in chronic kidney disease-associated pruritus. In Japan nalfurafine, a κ-opioid receptor agonist, has been licensed for this indication. UVB light may also attenuate uremic symptoms. In patients suffering from hepatobiliary disorders the sequestrant cholestyramine and the enzyme inducer rifampicin are effective. Furthermore, μ‑opioid receptor antagonists and sertraline may be used to ameliorate cholestatic pruritus. So far, no randomized controlled trials have been performed for chronic itch in other internal medicine disorders. Antipruritic treatment is mainly based on effective therapy of the underlying disease.

Chronic kidney disease-associated pruritus: impact on quality of life and current management challenges

Chronic kidney disease-associated pruritus (CKD-aP) is a distressing, often overlooked condition in patients with CKD and end-stage renal disease. It affects ~40% of patients with end-stage renal disease and has been associated with poor quality of life, poor sleep, depression, and mortality. Prevalence estimates vary based on the instruments used to diagnose CKD-aP, and standardized diagnostic instruments are sorely needed. Treatment studies have often yielded conflicting results. This is likely related to studies that are limited by small sample size, flawed designs, and nonstandardized diagnostic instruments. Several large well-designed treatment trials have recently been completed and may soon influence CKD-aP management.

Diagnosis and Management of Chronic Pruritus: An Expert Consensus Review

The aim of this study is to formulate the best clinical practice in the diagnosis and management of chronic pruritus (CP). We searched PubMed, EMBASE, Scopus, Web of Science, and the WHO's regional databases, for studies on "Diagnosis and management of chronic pruritus" from January 1, 2014, to July 31, 2015. We included programmatic reports and hand-searched references of published reviews and articles. Two independent reviewers screened articles and extracted data. We screened 87 of 95 studies that contained qualitative data. Avoid: Dry climate, heat, alcohol compress, ice packs, frequent bathing and washing, intake of very hot and spicy food, intake of alcohol, contact with irritant substances, excitement, strain and stress, and allergens. Using: Mild nonalkaline soaps, moisturizers, bathing oils, lukewarm water while bathing, soft cotton clothing and night creams/lotions, relaxation therapy, autogenic training, psychosocial education, educating patients to cope with itching and scratching, and educational programs. Especially use of moisturizers is considered important. In addition, symptomatic treatment options include systemic H1 antihistamines and topical corticosteroids. Symptomatic therapy directed toward the cause (hepatic, renal, atopic, polycythemia, etc.). If refractory or cause is unknown, consider capsaicin, calcineurin inhibitors for localized pruritus and naltrexone, pregabalin, ultraviolet therapy, Cyclosporine for generalized itching. CP is quite frequent finding associated with skin and systemic diseases in the overall population. It is known to significantly affect quality life score of an individual and also adds burden on the health-care cost. A specific recommendation for treatment of CP is difficult as a result of varied and diverse possibility of underlying diseases associated with CP.

Therapeutic Effects of Omega-3 Fatty Acids on Chronic Kidney Disease-Associated Pruritus: a Literature Review

Uremic pruritus remains one of the most tormenting, frequent and potentially disabling problem in chronic kidney disease (CKD) patients. However, an area of substantial etiological interest with relation to uremic pruritus is the essential fatty acids deficiency. So we performed a literature review to elucidate the efficacy of omega-3 fatty acids on uremic pruritus. This review evaluated all of the studies published in English language, focusing on the clinical effects of omega-3 fatty acids on uremic pruritus. The literature review was conducted in December 2015 and carried out by searching Scopus, Medline, Cochrane central register of controlled trials, and Cochrane database of systematic reviews. The search terms were "kidney injury", "kidney failure", "chronic kidney disease", "end-stage renal disease", "dialysis", "hemodialysis", "peritoneal dialysis", "pruritus", "itch", "skin problems", "fish oil", "omega 3", "n-3 fatty acids", "polyunsaturated fatty acids", "docosahexaenoic acid", and "eicosapentaenoic acid". Four small studies investigating potential benefits of omega-3 fatty acids on symptoms of uremic pruritus were found. Among them, three small randomized controlled trials have shown a significant improvement in pruritus symptoms (evaluated by a standard questionnaire) in CKD patients who took omega-3 supplement compared to omega-6, omega-9, and placebo supplementation. Despite numerous limitations of the studies, it is worth noting that even minor reduction in itching symptoms may be clinically significant for CKD patients. Therefore, and considering multiple health benefits of omega-3 fatty acids in advanced CKD and negligible risk profile, omega-3 intake can wisely be applied to CKD patients with uremic pruritus.

Pharmacological interventions for pruritus in adult palliative care patients

BACKGROUND

This is an update of the original Cochrane review published in 2013 (Issue 6). Pruritus occurs in patients with disparate underlying diseases and is caused by different pathologic mechanisms. In palliative care patients, pruritus is not the most prevalent but is one of the most puzzling symptoms. It can cause considerable discomfort and affects patients' quality of life.

OBJECTIVES

To assess the effects of different pharmacological treatments for preventing or treating pruritus in adult palliative care patients.

SEARCH METHODS

For this update, we searched CENTRAL (the Cochrane Library), and MEDLINE (OVID) up to 9 June 2016 and Embase (OVID) up to 7 June 2016. In addition, we searched trial registries and checked the reference lists of all relevant studies, key textbooks, reviews and websites, and we contacted investigators and specialists in pruritus and palliative care regarding unpublished data.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing the effects of different pharmacological treatments, compared with a placebo, no treatment, or an alternative treatment, for preventing or treating pruritus in palliative care patients.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the identified titles and abstracts, performed data extraction and assessed the risk of bias and methodological quality. We summarised the results descriptively and quantitatively (meta-analyses) according to the different pharmacological interventions and the diseases associated with pruritus. We assessed the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and created 10 'Summary of findings' tables.

MAIN RESULTS

In total, we included 50 studies and 1916 participants in the review. We added 10 studies with 627 participants for this update. Altogether, we included 39 different treatments for pruritus in four different patient groups.The overall risk of bias profile was heterogeneous and ranged from high to low risk. However, 48 studies (96%) had a high risk of bias due to low sample size (i.e. fewer than 50 participants per treatment arm). Using GRADE criteria, we downgraded our judgement on the quality of evidence to moderate in seven and to low in three comparisons for our primary outcome (pruritus), mainly due to imprecision and risk of bias.In palliative care participants with pruritus of different nature, the treatment with the drug paroxetine, a selective serotonin reuptake inhibitor, reduced pruritus by 0.78 points (numerical analogue scale from 0 to 10; 95% confidence interval (CI) -1.19 to -0.37; one RCT, N = 48, quality of evidence: moderate) compared to placebo.For participants suffering from uraemic pruritus (UP), gabapentin was more effective than placebo (visual analogue scale (VAS): 0 to 10), mean difference (MD) -5.91, 95% CI -6.87 to -4.96; two RCTs, N = 118, quality of evidence: moderate). The κ-opioid receptor agonist nalfurafine showed amelioration of UP (VAS 0 to 10, MD -0.95, 95% CI -1.32 to -0.58; three RCTs, N = 422, quality of evidence: moderate) and only few adverse events. Moreover, cromolyn sodium relieved UP participants from pruritus by 2.94 points on the VAS (0 to 10) (95% CI -4.04 to -1.83; two RCTs, N = 100, quality of evidence: moderate) compared to placebo.In participants with cholestatic pruritus (CP), data favoured rifampin (VAS: 0 to 100, MD -24.64, 95% CI -31.08 to -18.21; two RCTs, N = 42, quality of evidence: low) and flumecinol (RR > 1 favours treatment group; RR 1.89, 95% CI 1.05 to 3.39; two RCTs, N = 69, quality of evidence: low) and showed a low incidence of adverse events in comparison with placebo. The opioid antagonist naltrexone reduced pruritus for participants with CP (VAS: 0 to 10, MD -2.26, 95% CI -3.19 to -1.33; two RCTs, N = 52, quality of evidence: moderate) compared to placebo. However, effects in participants with UP were inconclusive (percentage difference -12.30%, 95% CI -25.82% to 1.22%, one RCT, N = 32). Furthermore, large doses of opioid antagonists (e.g. naltrexone) could be inappropriate in palliative care patients because of the risk of reducing analgesia.For participants with HIV-associated pruritus, it is uncertain whether drug treatment with hydroxyzine hydrochloride, pentoxifylline, triamcinolone or indomethacin reduces pruritus because the evidence was of very low quality (e.g. small sample size, lack of blinding).

AUTHORS' CONCLUSIONS

Different interventions tended to be effective for CP and UP. However, therapies for patients with malignancies are still lacking. Due to the small sample sizes in most meta-analyses and the heterogeneous methodological quality of the included trials, the results should be interpreted cautiously in terms of generalisability.

Comparison of uremic pruritus between patients undergoing hemodialysis and peritoneal dialysis

Background

Uremic pruritus is a common, but unpleasant, complication of end-stage renal disease. The uremic burden may differ between hemodialysis (HD) and peritoneal dialysis (PD) patients. This difference may also change the clinical characteristics of uremic pruritus between the 2 modalities. In this study, we investigated the uremic pruritus between patients on HD and PD.

Methods

A total of 425 HD and 223 PD patients from the Clinical Research Center registry in Korea were included. Patients were assessed for pruritus intensity, scratching activity, pruritus distribution, and frequency of pruritus-related sleep disturbance using the visual analog scale and questionnaire.

Results

The prevalence of uremic pruritus was higher in PD patients than that in HD patients (62.6% vs. 48.3%, P = 0.001). In the multivariable logistic analysis, PD treatment was significantly associated with the prevalence of uremic pruritus (odds ratio, 1.76; 95% confidence interval, 1.20–2.57, P = 0.004) after adjustment for clinical variables. The visual analog scale score, representing a subjective intensity of itchiness, was significantly higher in PD patients (PD 2.11 ± 2.32 vs. HD 1.65 ± 2.28, P = 0.013) compared with HD patients. The intensity of uremic pruritus was independently related with serum albumin levels (β = –0.143, P = 0.006) in HD patients and total weekly Kt/V (β = –0.176, P = 0.028) in PD patients.

Conclusion

Our data demonstrate the difference in prevalence, intensity, and risk factors of uremic pruritus between HD and PD patients. These findings suggest that careful consideration for uremic pruritus might be needed in end-stage renal disease patients according to the dialysis modality.

Pruritus in Systemic Diseases: A Review of Etiological Factors and New Treatment Modalities

Pruritus is the most frequently described symptom in dermatology and can significantly impair the patient's quality of life. In 10–50% of adults with persistent pruritus, it can be an important dermatologic clue for the presence of a significant underlying systemic disease such as renal insufficiency, cholestasis, hematologic disorder, or malignancy (Etter and Myers, 2002; Zirwas and Seraly, 2001). This review describes the presence of pruritus in different systemic diseases. It is quite important to discover the cause of pruritus for providing relief for the patients experiencing substantial morbidity caused by this condition.

Evaluation of uraemic pruritus in long-term dialysis patients using a modified Chinese scale

AIM

To examine the reliability and validity of a modified Chinese version of the uraemic pruritus scale for measurement of different degrees of itching, as well as to identify the predictors for the severity of uraemic pruritus among long-term dialysis patients.

METHODS

Long-term dialysis patients (n = 110) were recruited for a cross-sectional study from a medical centre in Taiwan. A modified Chinese version of the uraemic pruritus scale was used to evaluate sleep disturbance and the severity, frequency and distribution of itching. Reliability was evaluated using item-total correlations, Cronbach's α, and intra-class correlation. Validity was evaluated by the content validity index, predictive and discriminative validity. Multiple linear regression was used on the predictors for the severity of uraemic pruritus.

RESULTS

After optimization for reliability, the scale retained seven items. The Cronbach's α was 0.86, and the results showed that the scale had predictive and discriminative validity. High intact-parathyroid hormone and creatinine clearance rate were important predictors for the severity of uraemic pruritus. The severity of uraemic pruritus was the important predictor for the sleeping disturbance.

CONCLUSION

The modified uraemic pruritus scale can discriminate between patients with a total pruritus score of ≥11 and those with a score of 0 points. The modified Chinese scale is a useful tool for clinically assessing the various degrees of itching among long-term dialysis patients. Our study validates that it could apply to clinical practice in assessment of uraemic pruritus.