Chen Yung-Chih, Chiu Wan-Ting, Wu Mai-Szu
Division of Nephrology, Chang Gung Memorial Hospital, Keelung, Taiwan.
Am J Kidney Dis. 2006 Jul;48(1):69-76. doi: 10.1053/j.ajkd.2006.03.082.
Pruritus is a bothersome symptom affecting up to 80% of dialysis patients. Lymphocyte and cytokine interaction has an important role in the pathogenesis of uremic pruritus. Gamma-linolenic acid (GLA) is associated with immune modulation of T lymphocytes and lymphokines. The aim of this study is to determine whether topical GLA can attenuate uremic pruritus.
Seventeen dialysis patients with refractory uremic pruritus who passed the screening criteria entered a prospective, randomized, double-blind, placebo-controlled, crossover study. They stopped all antipruritic therapy at least 2 weeks before the study and were randomly assigned to treatment with either GLA 2.2% cream or placebo-based cream applied to the entire body after taking a bath once a day and to pruritic sites 3 times a day for 2 weeks, and then the reverse treatment after a 2-week washout period. Severity of pruritus was evaluated by using a traditional visual analogue scale (VAS) and a modified questionnaire method (pruritus score [PS]). Hemogram, aspartate and alanine aminotransferases, bilirubin, albumin, blood urea nitrogen, creatinine, calcium, phosphate, and intact parathyroid hormone were measured.
Sixteen patients completed the study; 1 patient was withdrawn because of an allergic skin reaction. There were no significant differences between groups except for sex distribution. Median VAS and PS values between groups did not differ significantly at baseline. There is a greater antipruritic effect of GLA based on evaluation with both the VAS and PS. There is persistence of a residual effect into the second treatment period after GLA treatment.
GLA-rich cream is better than placebo-based cream for alleviating uremic pruritus. It is a useful adjuvant in the management of refractory uremic pruritus.
瘙痒是一种令人烦恼的症状，影响高达80%的透析患者。淋巴细胞和细胞因子的相互作用在尿毒症瘙痒的发病机制中起重要作用。γ-亚麻酸（GLA）与T淋巴细胞和淋巴因子的免疫调节有关。本研究的目的是确定局部应用GLA是否能减轻尿毒症瘙痒。
17名符合筛查标准的难治性尿毒症瘙痒透析患者进入一项前瞻性、随机、双盲、安慰剂对照、交叉研究。他们在研究前至少2周停止所有止痒治疗，随机分配接受2.2%GLA乳膏或安慰剂乳膏治疗，每天洗澡后全身涂抹一次，瘙痒部位每天涂抹3次，持续2周，然后在2周的洗脱期后进行反向治疗。使用传统视觉模拟量表（VAS）和改良问卷法（瘙痒评分[PS]）评估瘙痒严重程度。检测血常规、天冬氨酸和丙氨酸转氨酶、胆红素、白蛋白、血尿素氮、肌酐、钙、磷和完整甲状旁腺激素。
16名患者完成研究；1名患者因皮肤过敏反应退出。除性别分布外，各组之间无显著差异。两组之间的VAS和PS中位数在基线时无显著差异。基于VAS和PS评估，GLA具有更大的止痒效果。GLA治疗后，残余效应持续到第二个治疗期。
富含GLA的乳膏在减轻尿毒症瘙痒方面优于安慰剂乳膏。它是难治性尿毒症瘙痒管理中的一种有用辅助药物。
