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.     

Itch Severity Scale: a self-report instrument for the measurement of pruritus severity

Background Assessing pruritus severity is difficult because of its subjective nature. A questionnaire that takes into account how the symptom is perceived by the patient may provide a more accurate representation of the pruritus. However, recently developed questionnaires do not specifically quantify severity of the symptom. Objectives To develop a self‐report questionnaire to measure pruritus severity and to provide initial evidence of its validity and reliability. Methods We modified a previously developed interview for the characterization and evaluation of pruritus, which was completed along with the RAND‐36 Health Status Inventory and Dermatology Life Quality Index by patients with psoriasis‐associated pruritus. Exploratory factor analysis, studies of internal consistency, and correlation analyses with health‐related quality of life scores were used to help determine which components of the modified pruritus interview to include in the new questionnaire, the Itch Severity Scale (ISS). The ISS was then assessed for construct validity, internal consistency reliability and test–retest reliability. Results Seven of the initial 11 components of the modified pruritus interview were included in the ISS. ISS scores correlated moderately with physical (r = −0·483) and mental (r = −0·492) health composite scores of the RAND‐36 and strongly with Dermatology Life Quality Index scores (r = 0·628), evidence of construct validity. It had an internal consistency reliability of 0·80 and a test–retest reliability of 0·95. Conclusions Based on this preliminary evidence of validity and reliability, this new seven‐item ISS may be useful in comparing pruritus severity among different disease populations or in assessing pruritus treatment effectiveness.     

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.     

Neuropeptides and their receptors in psoriatic skin in relation to pruritus

BACKGROUND: Pruritus in patients with psoriasis has been reported to be more common than previously thought. OBJECTIVES: To determine the actual prevalence of pruritus in psoriasis according to severity of psoriasis and to verify the hypothesis of involvement of neuropeptides and their receptors in psoriatic pruritus. METHODS: We analysed questionnaire replies from 152 patients with chronic plaque-type psoriasis and we assayed the expression of neuropeptides and their receptors in lesional skin biopsies obtained from psoriatic patients with pruritus compared with those from psoriatic patients without pruritus, nonlesional skin of patients with pruritic psoriasis and normal controls by confocal laser scanning microscopy. RESULTS: Of the 152 patients with psoriasis, 112 (73.7%) had pruritus, and these patients had a higher mean Psoriasis Area and Severity Index (PASI) score than psoriatic patients without pruritus. There was positive correlation between the PASI score and the intensity of pruritus. Keratinocytes in the psoriatic plaques of patients with pruritus showed consistently increased expression of substance P receptor (SPR), high-affinity nerve growth factor receptor (TrkA) and calcitonin gene-related peptide receptor (CGRPR). CONCLUSIONS: Pruritus is a common feature in psoriasis. Considering the well-known roles of neuropeptides in pathogenesis of both psoriasis and pruritus, increased SPR, TrkA and CGRPR may be involved in the pathogenesis of pruritus in psoriasis and in the severity of psoriasis.     

Prevalence, correlates and characteristics of chronic pruritus: a population-based cross-sectional study

Pruritus is the most frequent symptom in dermatology. Its impact on quality of life is substantial. Epidemiological data on chronic pruritus (>6 weeks) at the population level is sparse, but is important in order to understand the burden and risk factors of this distressing symptom. The aim of this population-based cross-sectional study was to estimate the point, 12-month and lifetime prevalence of chronic pruritus, assessing its association with sociodemographic variables and describing its characteristics. A validated postal questionnaire was sent to 4,500 individuals in from the German General population. Three contact attempts were made. The response rate was 57.8% (n=2,540). The point prevalence of chronic pruritus was 13.5% (95% confidence interval (95% CI) 12.2-14.9%), 12-month prevalence 16.4% (15.0-17.9%) and lifetime prevalence 22.0% (20.4-23.7%). Multivariate analyses found only ethnic origin independently associated with chronic pruritus. The impact of chronic pruritus on quality of life and emotional well-being appears to depend on severity rather than on the presence of the symptom alone. This is the first study to investigate various prevalence estimates of chronic pruritus at the population level. Despite its limitations (self-report and potential self-selection) this study indicates a high burden of chronic pruritus in society.     

Pruritus of unknown origin: A retrospective study

BACKGROUND: Pruritus of unknown origin is a common complaint, and systemic causes must be considered. However, there is little data on how frequently systemic causes are responsible or whether any patient characteristics make a systemic cause more likely. OBJECTIVE: We attempted to determine how frequently pruritus of unknown origin had a systemic etiology in an outpatient population seen in a university dermatology department and whether any patient characteristics made a systemic explanation more likely. METHODS: This is a retrospective study using chart reviews and telephone interviews to collect data. RESULTS: Of 50 patients, 11 had a systemic cause of pruritus. Pruritus was the initial symptom of systemic disease in 7 of these patients. No patient characteristics were statistically associated with systemic causes of pruritus. CONCLUSION: Pruritus of unknown origin was the initial symptom of a systemic disease in 7 of 50 patients presenting to a dermatology clinic with this complaint. The underlying diseases included hypothyroidism, gastric adenocarcinoma, hepatitis C, HIV, laryngeal carcinoma, graft-versus-host disease, and chronic lymphocytic leukemia.     

Scratching and fasting: a study of pruritus and anorexia nervosa

An association between pruritus and eating disorders has been suggested. This study examined changes in pruritus during weight restoration in a homogeneous group of women with severe anorexia nervosa (n = 19), using a structured questionnaire, visual analogue scale, clinical examination and a range of serological markers. We demonstrated that itching is a clinical feature of anorexia nervosa, associated with low weight and resolving on weight restoration. Some 58% of the sample suffered pruritus at low weight in a stable hospital environment. There was a significant association between changes in body mass index and severity of pruritus (P = 0.033), with reduced itching on weight restoration. Pruritus occurred in the absence of abnormalities in thyroid, renal and hepatic function, serum androgens, oedema, dermatoses or compulsive washing. Scratching was manifest as 'scratch prurigo' in five cases. Where itching was present, it was experienced as severe. We discuss a variety of possible explanations, including psychopathology, endocrine factors, regional blood flow variation, eczema and the role of central opioid and serotonergic activity. We argue that anorexia nervosa should be considered in all patients at low weight presenting with pruritus, and pruritus should be considered to be a physical symptom of anorexia nervosa.     

Density of mast cells and intensity of pruritus in psoriasis vulgaris: a cross sectional study

Background:Psoriasis is a chronic and prevalent disease, and the associated pruritus is a common, difficult-to-control symptom. The mediators involved in psoriatic pruritus have not been fully established.Objective:To evaluate associations between the number of mast cells in psoriatic lesions and the intensity of pruritus.Methods:29 patients with plaque psoriasis were recruited. In all participants, Psoriasis Area and Severity Index and Body Surface Area were assessed. A questionnaire was administered to obtain clinical information and the Dermatology Life Quality Index. Pruritus was assessed using a visual analog scale and skin biopsies were performed for staining with Giemsa and Immunohistochemistry with C-Kit.Results:Pruritus was observed in 91.3% of our patients. Median VAS was 6 (p25-75: 2-8). The immunohistochemical method revealed a mean of 11.32 mast cells/field and Giemsa staining revealed a mean of 6.72 mast cells/field. There was no correlation between the intensity of pruritus and mast cell count, neither in Immunohistochemistry (p = 0.15; rho = -0.27) nor in Giemsa (p = 0.16; rho = -0.27). Pruritus did not impact on the Dermatology Life Quality Index (p = 0.51; rho = -0.13).Study limitations:The small sample size may be considered the main limitation of our study.Conclusions:Although mast cells are mediators of pruritus in many cutaneous diseases, our findings support that psoriatic pruritus is a complex disorder with multifactorial, complex pathophysiology, involving pruritogenic mediators others than mast cells.     

Pathophysiology of pruritus in atopic dermatitis: an overview

Pruritus is an essential feature of atopic dermatitis (AD) and the diagnosis of active AD cannot be made without the history of itching. Because of the high impact on life quality, most of the patients measure the severity of eczema by the intensity of pruritus rather than appearance of skin lesions. However, although pruritus is a cardinal symptom of AD, its mechanism and association with the cutaneous nervous system is not completely understood. Recently, a considerable progress has been achieved in clarifying the complex pathophysiology of pruritus in AD. As a cutaneous sensory perception, itch requires excitation of neuropeptide-containing free nerve endings of unmyelinated nociceptor fibers. It is well known that histamine and acetylcholine provoke itch by direct binding to 'itch receptors' and several mediators such as neuropeptides, proteases or cytokines indirectly via histamine release. Interestingly, some variations of these complex mechanisms could be demonstrated in patients with AD. This review highlights the recent knowledge of different mechanisms which may be involved in regulating pruritus in patients with AD potentially leading to new therapeutic applications for the treatment of itch in AD.     

Pruritus precipitated by hydroxyethyl starch: a review

Hydroxyethyl starch (HES) is widely used for fluid management in broad populations of patients, particularly in the surgery and intensive care settings. Pruritus, often manifested as pruritic crises, is increasingly being recognized as a common major adverse effect of HES administration. This iatrogenic form of pruritus is frequently severe and protracted with a serious negative impact on patient quality of life, including sleep disturbance, disruption of daily routine and mental distress. Such pruritus is generally refractory to available therapies and can persist for up to 12-24 months. All currently clinically available HES solutions entail the risk of pruritus, including those of diverse molecular weights and substitutions. Although dose dependent, HES-induced pruritus nevertheless can often be provoked by relatively low routine doses. The pathophysiological basis for pruritus is the widespread tissue deposition of HES, prominently in macrophages. HES tissue deposits are long lasting and sometimes massive. Usually several weeks elapse between HES exposure and the onset of pruritus. Consequently, it is important to inquire about prior HES exposure in the diagnostic evaluation of pruritus sine materia. Awareness about the scope of the pruritus problem needs to increase among physicians administering HES. Well-designed clinical outcome studies are needed to assess more fully the incidence, dose dependency and mechanisms of pruritus with particular HES solutions.     

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。     

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.     

Pruritus Gravidarum: A Clinical and Laboratory Study

Five hundred pregnant women attending obstetrics OPD were screened for the presence of pruritus. The patients with other dermatological causes of pruritus (other than specific dermatosis of pregnancy) were excluded from the study. The selected patients were further subjected to routine laboratory investigations including liver function tests and HBs Ag detection. The prevalence of pruritus in pregnancy was found to be 4.6% (23 cases). Ten patients were found to have specific dermatoses of pregnancy, including four cases of pruritus gravidarum and four of pruritic urticarial papules and papules of pregnancy. The prevalence of pruritus gravidarum was 0.8% of pregnancies. All the patients with pruritus gravidarum were primigravidae and had no clinical overlap with other specific dermatoses of pregnancy, jaundice, or intrahepatic cholestasis. One case of perinatal death was recorded among the pruritus gravidarum cases. This study has been helpful in determining the prevalence and severity of pruritus gravidarum in South India.     

Entwicklung eines deutschsprachigen Fragebogens zur Erfassung von chronischem Pruritus (AGP-Fragebogen)

Chronic pruritus may manifest itself clinically in terms of different duration, intensity and quality. There is no questionnaire assessing these parameters systematically. The study presents a pruritus questionnaire for the German speaking region (AGP-Questionnaire) developed by 4 experts in the field. It comprises questions on course, intensity and quality of pruritus, general health status, sociodemographic data, quality of life (QoL) and pruritus cognition. Standardised questionnaires such as the SF-12 Health Survey (recall period 4?weeks), the Hospital Anxiety and Depression Scale (HADS) and the Dermatology Life Quality Index (DLQI) were also used to assess the instrument's convergent validity. Feedback of the participants was obtained by a one-page evaluation sheet. 100 patients suffering from chronic pruritus of the university hospitals of Giessen, Heidelberg, Munich and Muenster participated in the study. This questionnaire is useful in providing a comprehensive and structured approach to assessing individual patients' chronic pruritus. The validity and sensitivity of this new pruritus questionnaire will require examination in further studies.     

Treatment of pruritus in early‐stage hypopigmented mycosis fungoides with aprepitant

Pruritus is a symptom that significantly affects the patient's quality of life in cutaneous T cell lymphoma (CTCL). The most effective treatments are those that address the condition itself; however, it is often not possible to control this symptom. Lymphoma‐related pruritus normally becomes more severe as CTCL progresses, constituting an important factor for quality of life in these patients. Substance P is a neuromodulator which appears to play a key role in pruritus. Aprepitant is a neurokinin‐1 receptor antagonist affecting the substance P receptor. So far, several cases have been documented with an antipruritic response to the drug aprepitant in advanced‐stage mycosis fungoides (MF). In this paper, we describe an excellent response to aprepitant in a female patient with severe pruritus secondary to hypopigmented stage I MF. We would also like to stress the absence of nausea and vomiting of this combined therapy of interferon and aprepitant. Aprepitant could improve tolerance to interferon.     

Aquagenic pruritus: associated diseases and clinical pruritus characteristics

Background: Aquagenic pruritus (AP) can be induced by systemic diseases. The distribution of underlying diseases in a representative patient collective has not been investigated. This retrospective study aimed to determine the frequency and pruritus‐specific parameter of systemic diseases in a series of patients. Patients and methods: Data of 39 patients with AP (24 f, 15 m; mean age: f: 51.3 ± 20.1, m: 57.2 ± 15.0 years) were obtained and statistically evaluated as follows: demographic data, pruritus characteristics, underlying diseases, family history. Results: 30.8 % of patients exhibited polycythemia vera or myelofibrosis (Group 1: G1), in 69.2 % (G2) no underlying disease was found. 25.6 % had lactose intolerance as possible contributing factor. Women were significantly more common in G2 (p < 0.01), with a lower mean age (p < 0.01) and longer duration of AP (18.9 years, p < 0.01). Conclusions: AP occurs frequently with polycythemia vera. Other underlying diseases are rare; in over half of the patients no cause can be detected. In 25 % lactose intolerance is present which possibly acts as co‐factor. Demographic parameters (age, gender) allow estimation of the possible underlying disease in AP. Pruritus characteristics are similar in all groups and not helpful in determining the origin of AP.     

Narrow-band ultraviolet B treatment for vitiligo,pruritus, and inflammatory dermatoses

BACKGROUND: Narrow-band ultraviolet B (NB-UVB) therapy has been used successfully for the treatment of inflammatory and pigmentary skin disorders including atopic dermatitis, psoriasis, mycosis fungoides, polymorphous light eruption, and vitiligo. METHODS: This is a retrospective review of the treatment outcomes of 117 consecutive patients with vitiligo, pruritus, and other inflammatory dermatoses, excluding those with psoriasis and CTCL, who were treated with NB-UVB between 1998 and 2001 at our institution. RESULTS: Approximately 80% of all patients showed improvement in their condition. NB-UVB phototherapy was well tolerated, with no serious adverse effects. In patients with vitiligo, 6.4% had an abnormal thyroid-stimulating hormone level and 6.5% had anemia. CONCLUSION: NB-UVB may be considered as a viable therapeutic option in the treatment of vitiligo, pruritus, and other inflammatory dermatoses. Long-term adverse effects and cost-benefit analysis of NB-UVB therapy compared to other treatment modalities remain to be determined.     

Improvement of pruritus and quality of life of children with atopic dermatitis and their families after joining support groups

Introduction  Atopic dermatitis places a large burden on patients and their families, with greater risk of emotional disorders and behavioural problems. Preliminary evidence suggests that support groups and educational programs are helpful in reducing stress, disease and pruritus severity and improves quality of life (QoL).
Objectives  To evaluate the intensity of pruritus and the QoL in children with atopic dermatitis and their families after joining support groups.
Material and methods  Subjects were randomly assigned to intervention or control group and completed the Children's Dermatology Life Quality Index (CDLQI) and Family Dermatitis Impact (FDI). Pruritus was evaluated by the Yosipovitch's questionnaire for pruritus. Each patient/family unit was considered as one 'patient'. Participants were divided into two different groups: one with children under 16 years and the second with patients' relatives. Each unit was accompanied during 6 months.
Results  Thirty-two patients and their relatives completed the questionnaires satisfactorily. After intervention, pruritus intensity was similar ( P =  0.42), but the pattern of pruritus improved in the intervention group. Overall QoL for CDLQI instruments improved significantly ( P <  0.01) and, when specific domains were analysed, personal relationships ( P =  0.02) and leisure ( P =  0.04) showed marked enhancement. FDI scores failed to demonstrate differences in the QoL of patients' relatives after treatment.
Conclusion  The improvement on pruritus and QoL showed that atopic dermatitis patients had benefits with the attendance to support groups. We consider that these non-pharmacological approaches can be a very effective accessory tools in the management of recalcitrant forms of the disease.