Psychometric evaluation of the multidimensional Uraemic Pruritus in Dialysis patients (UP-Dial) scale: comparison of haemodialysis and peritoneal dialysis patients with chronic pruritus.

BACKGROUND: High-quality patient-reported outcome (PRO) measures for dialysis patients with chronic pruritus are urgently needed. However, no known, well-validated multidimensional tools have been investigated to measure pruritus symptoms in dialysis patients. OBJECTIVES: To examine the psychometric properties of a multidimensional tool of chronic pruritus, the Uraemic Pruritus in Dialysis patients (UP-Dial) 14-item scale, by comparing haemodialysis and peritoneal dialysis modality. METHODS: This validation study used data from the Thai Renal Outcomes Research-Uraemic Pruritus, a prospective, multicentre, longitudinal study. Data for this study were collected from 1 February 2019 to 31 May 2022. The adult sample of 226 haemodialysis and 327 peritoneal dialysis patients fulfilled the criteria of chronic pruritus based on the International Forum for the Study of Itch. Psychometric properties of the UP-Dial included validity and reliability, as measured across haemodialysis and peritoneal dialysis patients. Patients completed a set of anchor-based measurement tools, including global itching, Dermatology Life Quality Index (DLQI), EuroQoL-5 dimension-5 level (EQ-5D-5L), Kidney Disease Quality of Life-36 (KDQOL-36), Pittsburgh Sleep Quality Index (PSQI), global fatigue, Somatic Symptom Scale-8 (SSS-8) and Patient Health Questionnaire-9 (PHQ-9). RESULTS: From the patient's perspective, face validity was satisfactory for both dialysis samples. Psychometric analyses of the UP-Dial for each dialysis sample had good convergent validity. Spearman rho correlations indicate a positively strong correlation (0.73-0.74) with global itching, a positively moderate correlation (0.33-0.58) with DLQI, PSQI, global fatigue, SSS-8 and PHQ-9, and a negatively moderate correlation (-0.39 to -0.58) with EQ-5D-5L and KDQOL-36. The discriminant validity was satisfactory with a group of moderate and severe burden of pruritus for both dialysis samples. For scale reliability, the UP-Dial revealed excellent internal consistency (Cronbach's α = 0.89 and McDonald's ω = 0.90) and reproducibility (intraclass correlation 0.84-0.85) for both dialysis samples. Regarding psychometric properties, no statistically significant differences between dialysis samples were observed (all P > 0.05). CONCLUSIONS: The findings reaffirm good measurement properties of the UP-Dial 14-item scale in haemodialysis and peritoneal dialysis patients with chronic pruritus. These suggest a transferability of the UP-Dial as a PRO measure in clinical trial and practice settings.

Itch is a common symptom in chronic kidney disease, especially for people experiencing end-stage kidney disease and receiving dialysis. Itching among dialysis patients can present and affect any part of the body. Although there has been improvement in dialysis treatment over time, chronic itching (itching lasting more than 6 weeks) remains under-recognized in dialysis patients. In recent years, a specific clinical tool called the Uraemic Pruritus in Dialysis patients (UP-Dial) has been developed to assess the severity and burden of itching in dialysis patients. However, a comprehensive tool for evaluating itching symptoms has yet to be tested in a large dialysis population (haemodialysis and peritoneal dialysis). We examined and validated the measurement properties of the UP-Dial scale in an adult sample of 226 haemodialysis and 327 peritoneal dialysis patients with chronic itching. Our study found that the UP-Dial had good measurement properties for evaluating the burden of itching symptoms among haemodialysis and peritoneal dialysis patients with chronic itching. Our findings support the use of UP-Dial to compare treatments for chronic itching clinical trials and track treatment responses in daily practice.

Extracellular vesicles as potential diagnostic markers for kidney allograft rejection.

Kidney transplantation is a highly effective treatment for end-stage kidney disease. However, allograft rejection remains a significant clinical challenge in kidney transplant patients. Although kidney allograft biopsy is the gold-standard diagnostic method, it is an invasive procedure. Since the current monitoring methods, including screening of serum creatinine and urinary protein, are not of sufficient sensitivity, there is a need for effective post-transplant monitoring to detect allograft rejection at an early stage. Extracellular vesicles are vesicles with a lipid bilayer that originate from different cell types in pathological and physiological conditions. The content of extracellular vesicles reflects the status of cells at the time of their production. This review comprehensively summarizes clinical, in vivo, and in vitro reports that highlight the potential of extracellular vesicles as diagnostic biomarkers for kidney allograft rejection. Clarification would facilitate differentiation between rejection and non-rejection and identification of the mechanisms involved in the allograft rejection. Despite increasing evidence, further research is necessary to establish the clinical utility of extracellular vesicles in the diagnosis and monitoring of allograft rejection in kidney transplant recipients. Using extracellular vesicles as non-invasive biomarkers for diagnosis of kidney allograft rejection could have tremendous benefits in improving patient outcomes and reduce the need for invasive procedures.

Effect of Curcuminoids on Contrast-Induced Acute Kidney Injury after Elective Coronary Angiography or Intervention: A Pilot Randomized, Double-Blind, Placebo-Controlled Study.

INTRODUCTION: The role of curcuminoids, a striking antioxidant, in prevention of contrast-induced acute kidney injury (CI-AKI) remains unknown. We aimed to evaluate the efficacy and safety of curcuminoids in preventing CI-AKI in patients undergoing elective coronary angiography (CAG) and/or percutaneous coronary intervention (PCI). METHODS: We randomized 114 patients who were undergoing elective CAG and/or PCI to receive curcuminoids, 4 g/day (1 day before and 1 day after the procedure, n = 56), or placebo (n = 58). Serum creatinine was assessed at baseline, 12, 24, and 48 h after contrast exposure. The primary endpoint was development of CI-AKI defined as serum creatinine increase ≥0.3 mg/dL within 48 h after contrast exposure. The secondary endpoint was the occurrence of kidney injury defined by >30% increase in urine neutrophil gelatinase-associated lipocalin (NGAL). RESULTS: Baseline characteristics were comparable between the two groups. Seven (12.7%) in curcuminoids group and eight (14.0%) in placebo group developed CI-AKI (p = 0.84). The incidence of increased urine NGAL was comparable in the placebo and curcuminoids group (39.6% vs. 50%, respectively; p = 0.34). None in both groups had drug-related adverse events. CONCLUSION: This is a pilot study to demonstrate the safety and tolerability of curcuminoids in patients undergoing elective CAG and/or PCI. Curcuminoids have no protective effects against kidney injury after elective CAG and/or PCI.