[Clinical features and prurigo nodularis in nephrogenic pruritus]. / Klinische Charakteristika und Prurigo nodularis bei nephrogenem Pruritus.

BACKGROUND: Nephrogenic pruritus (NP) is a well-known associated symptom in patients with chronic renal failure. The aim of the present study was to make a detailed dermatological analysis including distribution of excoriations and their correlation with pruritus characteristics. PATIENTS AND METHODS: Data on a total of 17 patients with NP (14 males, mean 65.4 ± SD 14.3 years) were subjected to retrospective analysis. Most of the patients developed NP after start of kidney disease; however, in 20 % of the patients, there was premonitory appearance of the symptom 18 months (median) earlier. A majority of patients reported neuropathic symptom qualities (burning, stinging). In 94.1 % of patients xerosis was present; in 58.8 %, prurigo nodularis. The latter group of patients had a longer duration of pruritus as well as up to 10 years longer duration of renal disease than those without prurigo. RESULTS: Pruritus characteristics of NP show a wide variance without a clear profile that is useful for clinical diagnosis. NP can occur premonitorily, and, if of long duration and with coexistent metabolic diseases, can develop into prurigo.

Body concept of patients with chronic pruritus in relation to scratch lesions and psychic symptoms.

BACKGROUND: There are only a few studies about the body concept of patients with chronic pruritus. We examined the body concept of this group of patients taking into account subgroup-specific differences, limitations of quality of life and the comparison to patients with eating disorders and a healthy control group. METHODS: 284 participants with chronic pruritus filled in the Frankfurt Body Concept Scale, the Hospital Anxiety and Depression Scale and the Dermatology Life Quality Index. Statistical analysis was performed using t tests, variance analysis and Pearson's correlations. RESULTS: Patients with chronic pruritus had a more negative body concept than healthy individuals but a less negative concept than patients with eating disorders. Higher levels of depression and anxiety were related to a more negative body image. CONCLUSION: The body concept of patients with chronic pruritus should be taken into consideration when planning therapy. Whether the body concept changes after successful treatment has to be examined in further studies.

Prurigo as a symptom of atopic and non-atopic diseases: aetiological survey in a consecutive cohort of 108 patients.

BACKGROUND: Prurigo nodularis Hyde (PN) is a highly pruritic condition due to a vicious circle of repeated itching and scratching. There are no representative clinical studies investigating comorbidities in a large collective of PN patients. OBJECTIVE: This pilot study aimed to investigate the exact distribution of the coexisting diseases in a large representative consecutive cohort of PN patients. METHODS: A total of 108 PN patients (36.1% male; mean age of 61.5 ± 16.7 years) were enrolled in the study. RESULTS: In 87.0% of patients, diseases underlying PN could be established (18.5% skin disease, 7.4% systemic origin, 1.8% neurological diseases, 59.3% mixed origin). Due to several possible causative co-factors, the majority of patients were classified in the group of mixed origin (59.3%). In 53.1% of these patients, at least one dermatological factor was involved in the induction of PN. Interestingly, nearly half (46.3%) of all PN patients had either an atopic predisposition or atopic dermatitis as a single cause of PN (18.5%) or as one co-factor of PN of mixed origin (27.8%). Considering the different underlying diseases, there was no significant age or gender difference. CONCLUSION: PN does not seem to represent a characteristic symptom of one disease only. Multiple pruritogenic diseases are linked to evolution and improvement of PN upon treatment. Atopic predisposition is a major factor in nearly half of PN patients. The large collective of the present study helped detect a broad range of underlying diseases and thus to provide recommendations for rational diagnostics.

[Assessment of pruritus - current standards and implications for clinical practice : consensus paper of the Action Group Pruritus Parameter of the International Working Group on Pruritus Research (AGP)]. / Erfassung von Pruritus - aktuelle Standards und Implikationen für die Praxis : Konsensuspaper der Initiative Pruritusparameter der Arbeitsgemeinschaft Pruritusforschung (AGP).

With a prevalence of 20%, chronic pruritus is a symptom of many diseases with major impact on healthcare costs. The lack of specific therapeutic measures makes the development of new drugs and their testing in clinical trials urgent. It is not possible to measure pruritus in an objective way. For these reasons, it is necessary to have a series of standardized measures to characterize pruritus in a reliable way. Intensity scales such as the visual analog scale (VAS) are most frequently used to document the course of the symptoms. However, for assessing pruritus intensity, VAS is not an optimal instrument, although it cannot be dispensed with. The VAS should be combined with other scales in clinical studies in order to internally test the consistency of data. Other instruments for assessing intensity and course of pruritus are in the process of development. Presently scratch activity and scratch-associated lesions can be documented in a descriptive fashion. There are some studies that have employed devices to document scratch activity; however, methodological studies are not yet available. The patient-benefit index is an indispensable tool in clinical trials. A questionnaire for gathering data on the history and some pruritus-specific parameters has been developed and published. Questionnaires on patient quality of life, anxiety and depression are helpful in obtaining data on other cost-relevant parameters. A questionnaire on the quality of life, for instance, can provide important help in the assessment of the burden of the disease. The results of these questionnaires can be correlated with data on pruritus intensity scales. The relevant questionnaires have been partially digitalized so that they are available immediately as part of patient care. Additional methodological developments and studies are required in order to define a robust set of instruments for measuring pruritus in daily practice and in clinical studies.

[Chronic pruritus in autoimmune dermatoses : results of a comparative survey]. / Chronischer Pruritus bei Autoimmundermatosen : Ergebnisse einer vergleichenden Fragebogenstudie.

As the frequency and characteristics of chronic pruritus in autoimmune dermatoses (AID) have not yet been investigated, the present study aimed at characterizing pruritus in a representative group of patients with AID. A total of 35 patients (80% women) with AID were included, divided into 3 main groups (group 1; n = 19: bullous pemphigoid (BP), pemphigus vulgaris (PV); group 2; n = 9: scleroderma (SSc), morphea (Mo); group 3; n = 7: lupus erythematosus (LE), dermatomyositis (DM). Demographic data and pruritus characteristics were obtained by standardized questionnaires and statistically evaluated by SPSS 20.0. In group 1 (BP/PV) and group 3 (LE/DM), pruritus preceded the initial diagnosis of AID (2.1 ± 7.6 years and 9.5 ± 16.0 years). Patients in group 2 (SSc/Mo) reported pruritus initially 2.8 ± 8.6 years after the initial diagnosis. In group 1 (BP/PV) significantly (p < 0.05) more excoriations and relief by scratching were observed than in groups 2 (SSc/Mo) and 3 (LE/DM). While pruritus occurred as a prodromal symptom of BP/PV and LE/DM, it was only detected once the initial diagnosis of SSc/Mo was made. In contrast to BP/PV, the other forms of AID were associated with mechanically inducible pruritus with dysesthetic qualities. All forms of AID were associated with intensive pruritus which had a significant impact on quality of life.

Reduced intraepidermal nerve fibre density in lesional and nonlesional prurigo nodularis skin as a potential sign of subclinical cutaneous neuropathy.

BACKGROUND: Prurigo nodularis (PN) is a highly pruritic condition characterized by multiple hyperkeratotic nodules. Previous immunohistochemical studies demonstrated increased numbers of dermal nerve fibres. OBJECTIVES: Given that the sensation of pruritus is transmitted mainly by thin, unmyelinated epidermal nerves, the aim of our study was to investigate the intraepidermal nerve fibre (IENF) density. METHODS: Biopsies taken from lesional and nonlesional skin of 53 patients (37 women and 16 men; mean ± SD age 60·6 ± 14·9 years) with PN of diverse origin were immunostained for protein gene product 9·5. According to the guideline of the European Federation of Neurological Societies, the IENF density per millimetre was determined and compared with that in 20 healthy volunteers. RESULTS: Lesional and uninvolved PN skin biopsies showed significantly decreased IENF density (P < 0·001) regardless of patient age, origin of PN, intensity or quality of pruritus. CONCLUSIONS: Hypoplasia of epidermal sensory nerves independently of clinical parameters is a new finding in PN and suggests involvement of epidermal nerves in PN pathophysiology. To date, it cannot be ruled out that reduced IENF density is due to repeated scratching. However, the presence of hypoplasia in nonlesional PN skin suggests the presence of a subclinical small fibre neuropathy.

Prevalence of chronic pruritus in Germany: results of a cross-sectional study in a sample working population of 11,730.

BACKGROUND: Pruritus is a frequent symptom in many diseases; its prevalence in German adults is unknown. OBJECTIVE: Our purpose was to assess the prevalence, severity and health care of chronic pruritus in the German working population. METHODS: A cross-sectional observational study was conducted in employees of 144 German companies. Pruritus-specific data were obtained by standardized questions. RESULTS: 11,730 people (53.2% male, 16-70 years, mean = 43.7 years) were suitable for analysis. The point prevalence of chronic pruritus (at least 6 weeks prior to data collection) was 16.8%. The prevalence increased with age from 12.3% (16-30 years) to 20.3% (61-70 years). A quarter of the affected persons had suffered from pruritus for >5 years, 47% had never sought medical advice, and 94% had not undergone any treatment. CONCLUSIONS: Chronic pruritus is a prevalent symptom in the working age population. A high proportion of people affected are not medically treated.

Measuring patient-relevant benefits in pruritus treatment: development and validation of a specific outcomes tool.

BACKGROUND: The assessment of patient-relevant benefit is gaining importance in evaluating treatments. The 'Patient Benefit Index, standard version' questionnaire (PBI-S) is a validated instrument to assess patients' treatment needs and benefits in skin diseases. Before therapy, the patient rates the importance of predefined treatment goals; after therapy, he rates the extent to which these goals have been achieved. Thus far, no such instrument has been developed specifically for pruritus. OBJECTIVES: Development and validation of a patient-relevant benefit questionnaire in the treatment of pruritus. METHODS: Fifty patients with pruritus were questioned on impairments due to pruritus and treatment needs. Four treatment objectives not already covered by the PBI-S were added to obtain a disease-specific instrument. This was tested for feasibility by 36 patients with pruritus and validated in a sample of 100 patients with pruritus. RESULTS: The instrument was feasible in clinical practice. There were < 2% missing values. Cronbach's alpha of the needs questionnaire was 0.93. Convergent validity was demonstrated with respect to reduction of pruritus and quality of life. CONCLUSIONS: The PBI for pruritus is a feasible, reliable and valid instrument that is highly accepted in daily routine for recording patient-reported benefit.