Uremic Pruritus: From Diagnosis to Treatment

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.

Treatment of renal pruritus with dupilumab monotherapy: A case report

Chronic kidney disease-associated pruritus leads to decreased quality of life and is an independent risk factor for mortality. There is limited evidence for treatment of chronic kidney disease-associated pruritus, with only one on-label treatment approved by the FDA and Health Canada. We present a case of a 69-year-old female with a history of chronic kidney disease, who presented to clinic with a several-year history of diffuse, intense pruritus. There were no primary lesions. She was started on dupilumab 600 mg loading dose, then 300 mg subcutaneously every 2 weeks. At her follow-up appointment 5 months after initiation of dupilumab, she reported her pruritus as 1/10, with no interruptions in her sleep. Her creatinine remained elevated and was stable throughout the follow-up period. This case demonstrates sustained improvement in chronic kidney disease-associated pruritus with dupilumab. Further research is required to quantify the efficacy of dupilumab for treatment of chronic kidney disease-associated pruritus.

Data independent acquisition reveals in-depth serum proteome changes in uremic pruritus

Introduction: Uremic pruritus (UP) is a prevalent symptom in patients suffering from uremia, yet its underlying etiology and mechanisms remain incompletely elucidated. Given the significant incidence of UP, identifying specific alterations in proteins present in the blood of UP patients could offer insights into the potential biological pathways associated with UP and facilitate the exploration of biomarkers. Methods: In this study, we employed LC-MS/MS-based data-independent acquisition (DIA) mode to analyze serum samples obtained from 54 UP patients categorized as DKD-UP, HN-UP, and GN-UP (n = 18 for each subgroup), along with 18 uremic patients without pruritus (Negative) and 18 CKD patients without pruritus (CKD). Through DIA mode analysis, a total of 7075 peptides and 959 proteins were quantified. Within these, we identified four upregulated and 13 downregulated Differentially Expressed Proteins (DEPs) in DKD-UP versus Negative, five upregulated and 22 downregulated DEPs in HN-UP versus Negative, and three upregulated and 23 downregulated DEPs in GN-UP versus Negative. Furthermore, we conducted an intersection analysis of the DEPs across these three comparison groups to derive a set of common DEPs (COMP). Subsequently, a total of 67 common DEPs were identified in the three UP groups when compared to the CKD group, with 40 DEPs showing upregulation and 27 DEPs displaying downregulation. Results: Following Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses, we observed that the DEPs distinguishing UP from CKD were primarily associated with mitochondrial function (MT-CYB, PRDX2, TOMM22), inflammation (CD59, CSF1), renal injury (WFDC2), and neural function (CAP1, VGF). Discussion: Our findings contribute to a potential molecular comprehension of UP pathogenesis, shedding light on the identification of these DEPs as plausible biomarkers for UP.

Effectiveness of omega-3 fatty acid supplementation for pruritus in patients undergoing hemodialysis

Background

Patients undergoing hemodialysis (HD) frequently experience the chronic kidney disease-associated pruritus (CKD-aP).

Objective

The aim of this study was to investigate the effectiveness of omega-3 supplementation in the management of CKD-aP in patients undergoing hemodialysis.

Methods

In this triple blind, randomized clinical trial, the effect of the omega-3 supplement on uremic CKD-aP was assessed in 112 chronic hemodialysis patients at Caspian Hemodialysis Center in Rasht, Iran. Patients were randomly divided into the intervention group receiving omega-3 supplements (3 g/day) and the control group receiving placebo containing MCT oil for 2 months.

Results

Omega-3 supplementation had no effect on CKD-aP. The results did not change after adjusting for age and sex, additional adjustments for weight, height, physical activity, smoking, and alcohol use, additional adjustments for underlying diseases and weight, height, physical activity, smoking, and drinking alcohol, and further adjustments for underlying diseases and biochemical indices.

Discussion

Omega-3 supplementation for 2 months had no effect on CKD-aP in patients with CKD. Further studies with longer duration are warranted.

Clinical Trial Registration

https://www.irct.ir/trial/66638, IRCT20151226025699N6.

Characteristics of Xerosis, Pruritus, and Pallor in Stage 5 Chronic Kidney Disease Patients Undergoing Hemodialysis at Dr. Hasan Sadikin General Hospital, Bandung

Purpose

This study aims to delineate the demographic and clinical characteristics of xerosis, pruritus, and pallor among patients with stage 5 chronic kidney disease (CKD) undergoing hemodialysis at Dr. Hasan Sadikin General Hospital, Bandung.

Patients and Methods

This cross-sectional, descriptive study involved the analysis of 139 selected medical records of patients with stage 5 CKD who underwent hemodialysis between July and August 2022. A comprehensive examination was conducted by a dermatovenereologist, and the findings were duly recorded in the patients' medical records. The documentation encompassed gender, age, employment status, as well as the clinical characteristics of xerosis, pruritus, and pallor. The collected data were analyzed using descriptive statistical methods.

Results

Out of the 139 patients, 70 (50.4%) were male, while 69 (49.6%) were female. The mean (SD) age was 47.6 (11.8) years. The majority of the patients were unemployed (n=96, 69.1%). The median (IQR) duration of hemodialysis was 48 (96.0-24.0) months. The predominant findings were xerosis (n=84, 60.4%) and pallor (n=83, 59.7%), followed by pruritus (n=56, 40.3%). Instances of xerosis were more frequently observed in males, whereas pallor was more prevalent in females. Xerosis and pruritus exhibited higher prevalence in the ≥65 years age group, whereas pallor was more common in the 18-44 years age group. In contrast to xerosis, pruritus and pallor were more frequently noted in the unemployed group. Xerosis was predominantly mild with overall dry skin (ODS) score of one, and it was mainly observed on the patients' legs. Among those experiencing pruritus, over half displayed a moderate severity with visual analogue scale (VAS) scores ranging from ≥3 to <7. Patients with pallor mostly exhibited hemoglobin levels below 10 g/dL.

Conclusion

Xerosis, pruritus, and pallor were prevalent among patients with stage 5 CKD undergoing hemodialysis. These disorders presented with distinct demographic and clinical characteristics. Timely diagnosis and intervention have the potential to enhance the quality of life for these patients.

Early clinical observation of supra-hemodiafiltration with endogenous reinfusion in the treatment of uremic pruritus

BACKGROUND

To evaluate the clinical efficacy of supra-hemodiafiltration with endogenous reinfusion (Supra-HFR) for pruritus in uremic maintenance hemodialysis (HD) patients and explore the possible mechanism.

METHODS

This study prospectively included 60 patients with uremia who underwent maintenance hemodialysis and developed pruritus. Patients were randomly divided into a study group (30 cases) and a control group (30 cases). Patients in the study group underwent dialysis once a week with Supra-HFR and twice a week with HD. The group received HD dialysis 3 times a week. Visual analog scales (VAS) scores, 5-D itch scale scores, and 12-Item Pruritus Severity Scale (12-PSS) were used to evaluate the itching degree of patients. Quality of life was assessed using KDTA and SF-36 scores. Blood levels of hypersensitive C-reactive protein, calcium ion (Ca2+), phosphorus ion (P3+ ), free parathyroid hormone (iPTH), and β2-microglobulin (β2-MG) were compared between the two groups before treatment and at follow-up 24 weeks after treatment.

RESULTS

Before treatment, there was no significant difference in VAS, 5-D itch scale, and 12-PSS score between the study group and the control group (all p > 0.05). After 24 weeks of treatment, the VAS score of the study group (2.82 ± 0.91) was significantly lower than that of the control group (7.47 ± 1.32, p < 0.001), the 5-D itch scale score of the study group (9.47 ± 2.34) was significantly lower than that of the control group (18.53 ± 4.02, p < 0.001), the 12-PSS score of the study group (11.20 ± 1.81) was significantly lower than that of the control group (16.47 ± 2.09, p < 0.001). KDTA of the study group (64.17 ± 8.07 vs. 47.83 ± 13.46, p < 0.001) and SF-36 scores (65.37 ± 6.28 vs. 55.90 ± 14.28, p = 0.002) were significantly higher than that in the control group. The levels of hs-CRP, P3+ , iPTH, and β2-MG in the study group after treatment were lower than those before treatment, and lower than those in the control group after treatment (all p < 0.05).

CONCLUSIONS

The Supra-HFR can effectively reduce the itching symptoms of uremia patients and improve their quality of life.

Management of Uremic Xerosis and Chronic Kidney Disease (CKD)-Associated Pruritus (CKD-ap) With Topical Preparations: A Systematic Review and Implications in the Indian Context

Uremic xerosis and chronic kidney disease (CKD)-associated pruritus (CKD-ap) are the most commonly occurring dermatological problems faced by most of the CKD patients on hemodialysis which are not only annoying and draining to the patients but also have an intense effect on patients' quality of life. The PubMed, Scopus, Google Scholar, and Web of Science databases were searched for the literature with the following search terms: uremic xerosis OR CKD-ap OR uremic pruritus AND topical therapy OR topical ointment OR natural oil from the year 2002 -2022, and finally, 22 articles were chosen to write this review. Out of 22 studies, six used pharmacological preparations and remaining 16 studies used natural oils and components. All the articles were experimental studies (Pre/Quazi/RCT/True experimental) focusing on managing itch and xerosis associated with CKD and hemodialysis by topical application. The topical agents tried in various research studies are effective in managing itch and xerosis associated with CKD. They are safe, easy to use, and without allergic reactions. Natural oils like almond, chia seed, clove, glycerin, paraffin, and virgin coconut oil are readily available in home-care settings and can be used as a nurse-led intervention. Topical preparations for uremic xerosis and pruritus are effective, safe, and easy to apply on large body surface areas without systematic side effects. Natural oil-based topical preparations are cost-effective, safe, and easy to use.

Acupuncture for Uremic Pruritus: A Systematic Review and Meta-Analysis

Uremic pruritus (UP) is a chronic disease that can seriously affect the quality of life of dialysis patients. Acupuncture is a non-medication therapy that has been used to treat pruritus disorders. This systematic review aimed to evaluate the efficacy and safety of acupuncture for the treatment of UP. A total of nine Chinese and English databases were searched from their inception to December 31, 2021, and 214 studies were retrieved. Finally, seven randomized controlled trials (n=504) were included in the meta-analysis performed using RevMan V.5.3. Results included effective rate, recurrence rates, and adverse events. Compared with conventional treatment, acupuncture was more effective in treating UP (risk ratio [RR]=1.28, 95% confidence interval [CI]=1.09 to 1.50, P=0.003). The results were consistent after sensitivity analysis (RR=1.38, 95% CI=1.21 to 1.57, P<0.00001). In subgroup analysis, the efficacy rates of acupuncture and medications (oral and topical) were comparable (RR=1.20, 95% CI=0.98 to 1.47, P=0.07). Acupuncture combined with hemodialysis was more effective than hemodialysis alone in relieving pruritus (RR=1.42, 95% CI=1.18 to 1.72, P=0.0002). Adverse events were reported in only three studies, including one case of hyperphosphatemia in the medications group (RR=0.29, 95% CI=0.01 to 7.06, P=0.45). None of the studies reported recurrence rates. In conclusion, acupuncture is a safe treatment modality for patients with UP receiving hemodialysis that can effectively improve UP symptoms, and acupuncture in combination with hemodialysis has more efficacy than hemodialysis alone in improving the UP symptoms.

Arrhythmia and Heart Rate Variability during Long Interdialytic Periods in Patients on Maintenance Hemodialysis: Prospective Observational Cohort Study

Sudden cardiac death among hemodialysis patients is related to the hemodialysis schedule. Mortality is highest within 12 h before and after the first hemodialysis sessions of a week. We investigated the association of arrhythmia occurrence and heart rate variability (HRV) using an electrocardiogram (ECG) monitoring patch during the long interdialytic interval in hemodialysis patients. This was a prospective observational study with 55 participants on maintenance hemodialysis for at least six months. A patch-type ECG monitoring device was applied to record arrhythmia events and HRV during 72 h of a long interdialytic period. Forty-nine participants with sufficient ECG data out of 55 participants were suitable for the analysis. The incidence of supraventricular tachycardia and ventricular tachycardia did not significantly change over time. The square root of the mean squared differences of successive NN intervals (RMSSD), the proportion of adjacent NN intervals differing by >50 ms (pNN50), and high-frequency (HF) increased during the long interdialytic interval. The gap in RMSSD, pNN50, HF, and the low-frequency/high-frequency (LF/HF) ratio between patients with and without significant arrhythmias increased significantly over time during the long interdialytic interval. The daily changes in RMSSD, pNN50, HF, and the LF/HF ratio were more prominent in patients without significant arrhythmias than in those with significant arrhythmias. The electrolyte fluctuation between post-hemodialysis and subsequent pre-hemodialysis was not considered in this study. The study results suggest that the decreased autonomic response during interdialytic periods in dialysis patients is associated with poor cardiac arrhythmia events.