An epidemiology study of patients with uremic pruritus

BACKGROUND: Pruritus is a common problem in continuous ambulatory peritoneal dialysis (CAPD) and haemodialysis patients. There are few studies on the clinical characteristics of uremic itch, the cause of which is still unknown. OBJECTIVES: The aim of this study was to define the prevalence and clinical characteristics of pruritus in CAPD and haemodialysis patients. METHODS: A questionnaire was used to evaluate pruritus in 52 CAPD and 289 haemodialysis patients in two dialysis units. The relationship of various factors and medical parameters to itch was examined. RESULTS: Of the 341 patients, 177 (51.9%) had pruritus at the time of examination, 97 (28.4%) had pruritus in the past. Pruritus was present in 145 (50.2%) of the haemodialysis patients and 32 (61.5%) of the CAPD patients. Men, patients with liver disease, and patients with pruritus before starting dialysis treatment were more likely to have uremic pruritus. CONCLUSIONS: This study showed us that uremic pruritus was observed more in men than women. The high prevalence of uremic pruritus in our study does not support the decrease of pruritus due to an improvement in the management of dialysis patients.     

Hemodialysis-related pruritus and associated cutaneous manifestations

BACKGROUND: Uremic pruritus is one of the most common disabling problems in patients with chronic renal failure. Few studies have evaluated itching and cutaneous manifestations in hemodialysis-dependent patients. OBJECTIVES: The aim of this prospective study was to identify the prevalence of pruritus and cutaneous changes affecting patients undergoing hemodialysis. METHODS: The degree of itching in 70 patients treated at the Haemek Medical Center Hemodialysis Unit, in northern Israel, was scored according to presence and severity. We examined the relationship between the quality of dialysis and the frequency of pruritus, and identified concurrent cutaneous disorders. RESULTS: Pruritus was a common problem in the study cohort and affected 74.3% of hemodialysis patients at some point. The main characteristics of pruritus were a general pattern in 65.7% and mild intensity in 78.3% of observed patients. Duration of hemodialysis varied between 3 months and 13 years. There was no correlation between occurrence of pruritus and demographic or medical parameters (sex, type of kidney disease, regular medications or duration of hemodialysis) of the patients. Higher dialysis efficacy, as expressed by dialyser clearance, volume distribution of area, dialysis duration (Kt/v), may reduce the prevalence of pruritus (P < 0.02). None of the blood and chemical values considered (hemoglobin, creatinine, urea, phosphorus, calcium, albumin, parathormone and alkaline phosphatase) revealed any statistically relevant differences between pruritus groups. The appearance of foot ulcers was different between diabetic and nondiabetic individuals undergoing hemodialysis (P < 0.001). CONCLUSIONS: Pruritus is still a common problem in hemodialysis-dependent patients. The prevalence of xerosis and excoriations was high in patients undergoing replacement therapy. Efficient replacement hemodialysis may provide a clinical benefit.     

Efficacy and tolerance of the cream containing structured physiological lipids with endocannabinoids in the treatment of uremic pruritus: a preliminary study

Uremic pruritus is still a common phenomenon in patients with end-stage renal failure, however, there is no effective treatment of choice for this condition. This study was undertaken to evaluate the efficacy and tolerance of the cream with structured physiological lipids (DMS, Derma Membrane Structure) and endogenous cannabinoids in controlling pruritus in patients on maintenance hemodialysis. Twenty-one subjects with uremic pruritus completed the trial. All patients applied the tested cream twice daily for a period of three weeks. Pruritus was evaluated using two pruritus scoring methods: standard visual analog scale (VAS) and a questionnaire method. Moreover, all patients had dry skin scored according to the 5-point scale. Global pruritus and xerosis were examined before the trial, on study visits at weekly intervals, and on follow-up visit performed two weeks of study discontinuation. After 3-week therapy pruritus was completely eliminated in 8 (38.1%) patients. Pruritus evaluation by both scales revealed significant reduction of pruritus scores (p<0.0001) during the tested product application. At the beginning of the trial there was no significant correlation between the intensity of dry skin and severity of pruritus. The 3-week treatment period resulted in complete reduction of xerosis in 17 (81%) patients, while xerosis scores were significantly reduced (p=0.0001) throughout the study period. The test product was very well tolerated by all patients. The test product appeared to be effective in reducing both pruritus and xerosis in hemodialysis patients. It is very probable that the observed decrease of pruritus with the test product therapy was not only the result of dry skin improvement but that the addition of endocannabinoids may have also played a role. These preliminary results are encouraging, however, additional controlled studies are needed to clarify the exact usefulness of this product in therapy of uremic pruritus.     

Gabapentin for uremic pruritus: a systematic review of randomized controlled trials

Uremic pruritus is one of the most prevalent and bothersome dermatologic symptoms in patients with end-stage renal disease. Some studies suggest a possible neuropathic cause of uremic pruritus. Gabapentin, an anticonvulsant, may control pruritus with neuropathic origin. The objectives of this study were to assess the efficacy of gabapentin in reducing pruritus scores of patients with uremic pruritus and evaluate its safety among dialysis patients. Meta-analysis of randomized controlled trials, using gabapentin as treatment for uremic pruritus among hemodialysis patients was included and analyzed using Review Manager Version 5.1.4 software. Seven out of 17 screened articles were included, with a total of 315 participants. Meta-analysis of the incidence of improved pruritus scores after treatment from four studies (n = 171) showed that treatment with gabapentin decreased the severity of uremic pruritus as compared to the placebo (risk ratio = 0.18; 95% confidence interval: 0.09, 0.33; I² = 4%: P =< 0.00001). Six studies (n = 290) presented with incidence of adverse drug events such as dizziness, drowsiness, and somnolence. In the pooled analysis, treatment with gabapentin was associated with a higher incidence of adverse drug events compared to the comparator drugs, but the results were not significant (risk ratio = 1.3, 95% confidence interval: 0.81, 2.11; P = 0.28, I² = 37%). The results of this systematic review suggest that gabapentin is efficacious and safe in improving uremic pruritus among dialysis patients.     

Uremic pruritus: a clinical study of maintenance hemodialysis patients

Uremic pruritus is one of the most bothersome symptoms in patients with chronic renal failure. Its pathogenesis remains unclear. The aim of this study was to evaluate the frequency of uremic pruritus in hemodialysis patients and to correlate its presence and intensity with several clinical parameters. One hundred thirty patients on maintenance hemodialysis were included into the study. The intensity of pruritus was assessed by two methods: visual analog scale and specially adapted questionnaire scoring method. A significantly positive correlation (p < 0.00001) was demonstrated between the two methods for evaluating pruritus. Uremic pruritus was found in 40.8% of patients. An additional 36.1% of patients reported pruritus to have been present in the past during the renal disease period. Itching was generalized in 19% of patients; the remaining subjects suffered from scattered pruritus (50%) or pruritus in a single location (31%). A significant positive relationship (p < 0.02) was demonstrated between the total score of pruritus and duration of the hemodialysis period. Severity of pruritus and sleep disturbance caused by itching also significantly correlated (p < 0.05) with the duration of hemodialysis. Patients hemodialysed on polysulphone membranes more commonly suffered from pruritus than those on hemophane (p < 0.04) or cuprophane (p < 0.03) dialysis membranes. A marked relationship was demonstrated between the intensity of xerosis and prevalence of pruritus. Significantly more patients with very rough skin had pruritus compared to those with rough skin (p < 0.05) and those with slightly dry skin (p < 0.02). Itching was more common in female patients (p < 0.04), but patient age, underlying renal disease and erythropoietin intake did not correlate with the incidence or intensity of pruritus.     

A comparative study on the effects of naltrexone and loratadine on uremic pruritus

BACKGROUND: Two recent studies have provided opposite results on the efficacy of naltrexone on uremic pruritus. We have performed a third study. OBJECTIVE: To compare the efficacy and tolerance of naltrexone and loratadine in uremic pruritus. PATIENTS/METHODS: Among 296 hemodialyzed patients, 65 suffered from uremic pruritus. Fifty-two patients participated in the study. The patients were treated for 2 weeks with naltrexone (50 mg/day; 26 patients) or loratadine (10 mg/day; 26 patients), after a washout of 48 h. Pruritus intensity was scored by a visual analogue scale (VAS). Adverse events were carefully searched for. The two groups were statistically equivalent. RESULTS: There was no significant difference in the mean VAS scores after treatment, but naltrexone allowed a dramatic decrease in VAS scores (Delta >3/10) in 7 patients. Adverse events (mainly nausea and sleep disturbances) were observed in 10/26 patients. CONCLUSIONS: Naltrexone is effective only in a subset of patients. Adverse events are very frequent. The differences of efficacy and tolerance between patients might be due to metabolism. Naltrexone might be considered as a second-line treatment.     

Patients' perspective of pruritus in chronic plaque psoriasis: a questionnaire-based study

Background  Pruritus in psoriasis patients has not been regarded as a major symptom.
Objective  To study the pattern of pruritus in chronic plaque psoriasis.
Methods  A questionnaire was sent out to 109 patients with a diagnosis of chronic plaque psoriasis, who attended our outpatient departments during the period of January 2006 to January 2007.
Results  Out of 109 patients, 80 patients (74%) answered the questionnaire. Pruritus was found in 80% of the patients, with an intensity of 5.2 ± 2.6 (±SD) using a visual analogue scale (0–10). The frequency and intensity of pruritus were higher in women. Lower leg and scalp were reported to be the most commonly affected sites. Major aggravating factors for pruritus were stress and dryness of skin. Sun, sleep and vacation could relieve pruritus. The most common antipruritic treatments used by the patients were topical steroids, topical vitamin D, emollients and ultraviolet light therapy, whereas antihistamines were used by a small number of patients. Mood, concentration and sleep were negatively affected by pruritus.
Conclusion  Pruritus is a common symptom in patients with chronic plaque psoriasis.     

The sensitivity of uremic and normal human skin to histamine

Cutaneous reactions induced by intradermal histamine injection were studied in uremic patients with and without pruritus who were undergoing maintenance hemodialysis and also in healthy subjects. Flare reactions were significantly smaller in both groups of patients than in controls. However, the itch responses following histamine injection were greater in patients with pruritus than in non-pruritic patients and healthy subjects, indicating an augmented sensitivity to pruritogens in these patients. The development of histamine tachyphylaxis was demonstrated in healthy human skin. After repeated histamine injections at intervals of 90 min, both itch and flare responses decreased rapidly. A similar decline in histamine reactivity occurred when the interval between injections was extended to 24 h. The phenomenon of histamine tolerance was confirmed in 2 uremic patients.     

A questionnaire for the assessment of pruritus: validation in uremic patients

A questionnaire was constructed for the evaluation and measurement of pruritus. The questionnaire, based on the short form of the McGill Pain Questionnaire, was tested in 145 patients suffering from uremic pruritus and currently undergoing hemodialysis treatment in 3 centers. The newly developed questionnaire proved to be reliable and provided valid data on the sensory, affective and overall intensity of uremic pruritus. The data suggest that uremic pruritus tends to be prolonged, frequently intense and a major source of distress to the patient. Dialysis was not found to influence the pruritus. The questionnaire may also be useful in pruritus secondary to other causes.     

The incidence of hydroxyethyl starch-associated pruritus

BACKGROUND: Pruritus due to hydroxyethyl starch (HES) is reported with a very variable frequency but appears to be relatively uncommon in the U.K. compared with other European countries. OBJECTIVES: To determine the frequency of HES-related pruritus in patients discharged from intensive care units (ICUs) in two U.K. hospitals. METHODS: A questionnaire survey was given to 253 patients after discharge from ICU. Questions were designed to exclude pre-existing skin disease and other causes of pruritus. RESULTS: One hundred and fifty-nine completed questionnaires were suitable for analysis. Seventeen of 135 (12.6%) subjects who had received HES reported itch, as did one of 24 who had not received HES. There was no apparent relationship between the occurrence of HES-related pruritus and either the surgical indication or the brand or volume of HES infused. CONCLUSIONS: HES-related pruritus is a problem that dermatologists need to recognize; however, its frequency in the U.K., when other causes of itch are excluded, appears to be lower than suggested in some previous reported studies.     

Clinical characteristics of pruritus in chronic idiopathic urticaria

BACKGROUND: Although pruritus is a predominant symptom of chronic idiopathic urticaria (CIU) its clinical characteristics have not been explored. OBJECTIVES: To characterize the clinical pattern and sensory and affective dimensions of the itch experience, utilizing a comprehensive itch questionnaire. METHODS: A structured questionnaire based on the McGill pain questionnaire was used in 100 patients suffering from CIU randomly recruited from a tertiary referral centre. RESULTS: All 100 patients recruited with CIU completed the questionnaire. In 68 patients pruritus appeared on a daily basis. Most patients experienced their pruritus at night and in the evening (n = 83), and 62 reported difficulty in falling asleep. Pruritus involved all body areas, but mostly the arms (n = 86), back (n = 78) and legs (n = 75). Accompanying symptoms were a sensation of heat in 45 patients and sweating in 15. Most patients (n = 98) were prescribed antihistamines (mainly sedating), of whom 34 experienced long-term relief. The sensation of itch was reported to be stinging (n = 27), tickling (n = 25) and burning (n = 23). Seventy-six patients found their pruritus bothersome, 66 annoying and 14 complained of depression. The itch intensity at its peak was more than double that felt after a mosquito bite. The worst itch scores of those who felt depressed were significantly higher than of those who did not (P = 0.018). There was a positive correlation between the sensory and affective scores during worst itch (P < 0.001). CONCLUSIONS: This study describes the itch experienced in CIU, highlighting sensory and affective dimensions. The itch questionnaire was found to be a valuable tool for evaluating pruritus in CIU and its unique features.     

Computerized recording of itch in patients on maintenance hemodialysis

Itch was assessed both continuously using a computerized method, Pain-Track, and retrospectively using visual analogue scales (VAS) by 28 patients undergoing maintenance hemodialysis and suffering from uremic pruritus. Measurements were performed during 7 consecutive days including three dialysis sessions. Pain-Track recordings showed that itch intensity was greater during dialysis than on days following dialysis (p less than 0.05). Possible explanations are that pruritogenic substances might be released during treatment or that removal of such substances during dialysis leads to amelioration of symptoms after treatment. Alternatively, lowering of the sensory threshold due to general discomfort in association with dialysis may exacerbate the itch intensity. There was no consistent difference between daytime and bedtime itch scores over the week, except on the second day without treatment, when bedtime itch ratings significantly exceeded those during the day (p less than 0.05), suggesting that factors other than inactivity are essential for this peak in itch intensity. Thus, after 2 days without treatment, when patients become increasingly metabolically deranged, they reported maximal itch, implying that the accumulation of pruritogenic substances is of major importance in the pathogenesis of uremic pruritus. There was a positive correlation between Pain-Track and VAS data, although significant fluctuations in itching could be detected only with Pain-Track.     

Focus groups in Swedish psoriatic patients with pruritus

Pruritus is a common complaint among patients of psoriasis vulgaris of the chronic plaque type. Despite a high prevalence of pruritus in psoriasis, limited information is available on this subject. The aim was to assess patients' perspective of pruritus in psoriasis vulgaris of plaque type, by using focus groups. A total of 20 patients with chronic plaque psoriasis participated in focus group discussions and were divided into five groups, on different occasions. Themes for the discussion were introduced and moderated by the investigators. The focus groups created a proper atmosphere for discussion on different aspects of pruritus in psoriasis. The patients regarded themselves able to discriminate between pruritus and pain. Pruritus was most common on the lower back and legs. Stress, cold weather and skin dryness were seen as the most common worsening factors for pruritus. Sunbathing and application of emollients with or without steroids and calcipotriol cream were suggested as factors that relieved pruritus. Quality of life was affected in some patients, for instance they were reluctant to participate in social activities. Patients' perspectives on pruritus in psoriasis were important for a better understanding of this sensation. The information collected from the focus group discussions might be useful for further study in this area.     

Current and Emerging Therapies for Itch Management in Psoriasis

Pruritus is a common and significant symptom among patients with psoriasis. Pruritus is often present beyond the borders of psoriatic plaques, and frequently affects the scalp and genital regions. Psoriatic itch may be severe and can profoundly affect quality of life and sleep, even in the context of mild-to-moderate disease. These features often make the treatment of psoriatic pruritus challenging. However, there are a variety of effective topical and systemic treatment modalities available to address this symptom. While there remains a need for treatments that specifically target psoriatic itch, newly licensed therapies including secukinumab, ixekizumab and apremilast have been shown to rapidly and effectively mediate itch reduction.     

Chronic pruritus: a paraneoplastic sign

Chronic itch could be a presenting sign of malignancy. Pruritus of lymphoma is the common prototype of paraneoplastic itch and can precede other clinical signs by weeks and months. Paraneoplastic pruritus has also been associated with solid tumors and is an important clinical symptom in paraneoplastic skin diseases such as erythroderma, Grovers disease, malignant acanthosis nigricans, generalized granuloma annulare, Bazex syndrome, and dermatomyositis. In any case with high index of suspicion a thorough work-up is required. This review highlights the association between itch and malignancy and presents new findings related to pathophysiological mechanisms and the treatment of itch associated with malignancy. Combinative therapies reducing itch sensitization and transmission using selective serotonin and neuroepinephrine reuptake inhibitors, Kappa opioids, and neuroleptics are of prime importance in reducing this bothersome symptom.     

Clinical characteristics of generalized idiopathic pruritus in patients from a tertiary referral center in Singapore

BACKGROUND: Generalized idiopathic pruritus is a rarely studied heterogeneous condition, where patients with non-inflamed, non-pathologic skin complain of widespread pruritus. METHODS: We had administered a detailed pruritus questionnaire, based on the short form of the McGill pain questionnaire, on 75 patients with this condition. RESULTS: All 75 patients recruited with generalized idiopathic pruritus completed the questionnaire. In 92% of the patients, pruritus appeared on a daily basis. Most patients experienced pruritus at night (56%) and in the evening (61%) and 69% had difficulty falling asleep. Pruritus mainly involved the legs (79%), arms (76%) and back (68%). Accompanying symptoms were heat sensation (17%) and pain (13%). 80% had been prescribed antihistamines, of whom 56% obtained short-term relief. The sensation of itch has been reported to be crawling (33%), tickling (20%), stinging (19%) and burning (19%). Patients also reported that the itch was unbearable (73%), bothersome (72%), annoying (67%) and worrisome (45%). The worst-state VAS scores were significantly higher in patients who reported agitation (P = 0.006), difficulty in concentration (P= 0.010) and anxiety (P= 0.033). CONCLUSION: This study describes the sensory and affective dimensions of generalized idiopathic pruritus, and this questionnaire has been found to be a useful tool for evaluating pruritus in this condition.     

银屑病患者瘙痒特征及其对生活质量的影响

目的:确定银屑病患者的瘙痒特征并评价其生活质量。方法:采用问卷调查的方法,评价银屑病患者的瘙痒特征和生活质量。结果:131例银屑病患者中有89.31%伴有不同程度的瘙痒,其中87.18%的患者因瘙痒影响心情,62.39%因瘙痒影响睡眠;相关分析显示,瘙痒强度、频率、持续时间与银屑病严重程度和皮损红斑、浸润、脱屑呈正相关(P0.05)。结论:大多数银屑病患者有不同程度的瘙痒,且对患者的生活质量产生的负面影响。