Search

The histopathology of psoriasis can lack classical features on certain anatomical sites. The aim of this study was to detail the histopathology and immunophenotype of psoriasis on the legs, in order to differentiate it from other inflammatory dermatoses, such as stasis dermatitis. The histopathology of psoriasis on the legs was retrospectively compared with psoriasis on the trunk and stasis dermatitis. Statistically, psoriasis on the legs was significantly less likely to show typical histological criteria of psoriasis, such as regular hyperplasia, suprapapillary thinning, and "kissing vessels". The most valuable criteria to distinguish psoriasis on the legs from stasis dermatitis were the presence of neutrophils in the cornified layer and staggered parakeratosis. In addition, an immunohistochemical panel (Ki-67, Bcl-2alpha, S100A7, CD3, MPO, CK10, CK16) revealed that staining with Ki-67 and MPO could be diagnostically useful. Since the cornified layer contains important histopathological clues to differentiate psoriasis on the legs from stasis dermatitis, clinicians should refrain from unnecessary rubbing during disinfection before taking a biopsy.

Chronic nodular prurigo presents with multiple pruriginous nodules and severe pruritus. This study aims to explore the treatment course and regimens in patients with chronic nodular prurigo and to analyse predictive factors contributing to therapeutic success. A total of 325 patients with chronic nodular prurigo (male 37.5%) were analysed concerning demographic data, pruritus intensity, medical history, psychological impairment, quality of life, treatment duration, regimens and outcome. These parameters were compared with 325 sex- and age-matched patients with chronic pruritus on non-lesional skin. Treatment success was dependent on duration and regime of treatment and independent of age, sex and initial itch intensity. Non-responders displayed a higher percentage of inflamed nodules, a higher portion of excoriated nodules and a higher impairment of quality of life and mood factors before initiation of treatment. Gabapentinoids and immunosuppressants proved to be the most successful therapeutic agents. Compared with patients with chronic pruritus, those with chronic nodular prurigo needed longer duration of therapy.

Chronic pruritus (CP) is often accompanied by paresthetic sensations like warmth, burning and stinging. The aim of this study was to analyze, whether divergent sensations are linked to structural and functional skin alterations in clinically diagnosed CP patients. Clinical responses to capsaicin, histamine, and to thermal and mechanical stimulation, intraepidermal nerve fiber density, and epidermal expression of transient receptor potential (TRP)-channels were investigated in healthy controls, and in CP patients, reporting either warmth (CP-W) or neuropathic sensations (CP-N). In CP-W, pinprick hyperalgesia and increased sensitivity to capsaicin were aligned with increased epidermal TRPV1 expression, while smaller histamine axon reflex erythema matched with significantly reduced intraepidermal nerve fiber density. CP-N showed earlier onset of sensations after capsaicin stimulation, significantly increased warmth detection threshold, and higher epidermal expression of TRPV4 compared to healthy controls. The present study contributes to the neurobiological understanding of the divergence of sensory sensations in CP, indicating new treatment targets.

Few studies have validated standard measurement instruments for evaluation of chronic pruritus. The Chronic Pruritus Tools Questionnaire PRURITOOLS assembles a set of instruments for the assessment of pruritus, such as the visual analogue scale (horizontal 100-mm line), numerical rating scale (0-10), verbal rating scale, and information on pruritus quality and improvement during therapy. This study, with 40 subjects, analysed PRURITOOLS regarding convergent validity and test-retest reliability (60 min), followed by a feasibility questionnaire. Test-retest reliability for PRURITOOLS items was excellent (intraclass correlation coefficient 0.84-1). Strong to very strong correlations between the pruritus intensity scales indicated convergent validity. The feasibility questionnaire showed an overall acceptance of PRURITOOLS, and the majority of subjects (82.5%) considered it an appropriate questionnaire to measure pruritus. In conclusion, PRURITOOLS offers validated tools for rapid pruritus assessment in routine care or endpoints of clinical trials.

Impaired sleep due to nocturnal pruritus is a common symptom in patients with chronic pruritus. However, there is no standardized, simplified instrument for assessing sleep-related problems in patients with chronic pruritus. After a literature search, we conducted 50 interviews with patients with chronic pruritus and tested 12 items most frequently used in routine sleep questionnaires. Afterwards, 2 sleep assessment questionnaires (Pittsburgh Sleep Quality Index; Regensburg Insomnia Scale) were selected for use in 88 patients with chronic pruritus with sleep impairment due to pruritus. They were completed twice; once before optimizing their individual pruritus therapy and once again after 4 weeks. During the latter survey, 21 patients reported that pruritus no longer negatively affected their sleep. These patients also achieved a significant improvement in their sleeping behaviour in the Regensburg Insomnia Scale. Therefore, the Regensburg Insomnia Scale appears to be well-suited to assessing sleep impairment in patients with chronic pruritus.

Performing a reliable assessment of chronic pruritus remains a challenge. Electronic diaries are often used, but many of the scales have not been validated. ItchApp© was developed for Android smartphones in order to address this lack. A total of 40 subjects with chronic pruritus completed questionnaires both on paper and with ItchApp© (verbal rating scale, numerical rating scale, dynamic pruritus score) in order to validate the software application. Strong correlations were found for test-retest reliability (intraclass correlation coefficient: 0.865-0.977) and convergent validity (Spearman's r: 0.442-0.924). A feasibility questionnaire for ItchApp© revealed a high level of user friendliness and compliance. This was confirmed in a randomized controlled trial with 68 subjects, for which the clinically important difference in the numerical rating scale values for ItchApp© was calculated (2.61 points). In summary, ItchApp© is a recently developed eDiary that can provide experts with a reliable evaluation of patients with chronic pruritus. It will be made available for future clinical trials.

Patients with chronic pruritus may develop scratch-induced lesions with elevated borders and central necrosis. This so-called umbilicated type of prurigo (UP) is rare and is assumed to develop preferentially in the context of metabolic diseases. The aim of this study was to characterize UP in its clinical and histological dimension. Demographic and clinical data were collected from 23 patients with UP. Intensive light microscopical analysis of biopsied lesions was performed. Statistical comparison with previous results for prurigo nodularis (PN) showed that UP is clearly a subtype of PN. In addition, clinical and microscopic features of epidermal perforation identical to those in acquired reactive perforating dermatosis (ARDP) were observed. Hence, we suggest that ARDP is identical to UP and is therefore a subtype of PN. We assume that reduced wound healing capacities due to underlying systemic disorders, particularly diabetes mellitus and uraemia, underlie the pathomechanism of development of umbilicated skin lesions with a perforating aspect.

Pruritus is a frequent sensation in dermatoses, but its prevalence in patients in dermatological practices has not been fully studied. The aim of this cross-sectional study is to investigate its prevalence and characteristics in all patients attending a dermatology practice in Germany over a period of one week (n = 334; 52.7% female; median age 45.0 years). The point prevalence of pruritus in this study population was 36.2% (87.6% of whom had chronic pruritus). It inhibited the everyday life of 73.6% of all patients, with 77.7% reporting a frequently to permanently experienced moderate intensity. (5.2 ± 2.3 on the numerical rating scale). Of the patients, 52.1% had previously consulted their general practitioner, and 62% had visited the dermatologist due to pruritus. This study shows that pruritus is a highly prevalent, clinically and economically relevant symptom in dermatological practices. The majority of patients suffering from chronic pruritus are severely burdened and medically underserved. Dermatologists should be aware that pruritus also occurs frequently in patients who do not primarily present due to their symptoms.

Severe persistent pruritus is a common, but incompletely characterized, complication of hydroxyethyl starch (HES) infusion. This retrospective study aimed to assess HES-induced pruritus by electron microscopic findings, pruritus characteristics, and response to stimuli, and to determine the impact of HES dosage, molecular weight and substitution. Seventy patients with electron micro-scopy-proven HES-induced pruritus were included. HES-laden vacuoles were observed in skin macrophages of all patients. The median latency between HES exposure and pruritus onset was 3 weeks, and the median duration of pruritus was 6 months. Pruritus was severe, or very severe, in 80% of patients. Mechanical stimuli triggered pruritus in 74% of patients. Although the median cumulative dose of HES was 300 g, 15% of patients developed pruritus after only 30 g. There were no significant differences between HES 130/0.4 and HES 200/0.5 in pruritus latency, duration or severity. HES-induced pruritus thus may occur at any dose, molecular weight or substitution.

Notalgia paraesthetica is a neuropathic pruritus on the back. The aim of this retrospective study was to examine patient characteristics in a consecutive cohort from Brazil and Germany. A total of 65 patients (49 women, 16 men; age range 25-80 years, mean 56.2 ± 12.7 years; median 57.0 years) were investigated in order to determine the spinal or peripheral origin of notalgia paraesthetica. Protein gene product 9.5-positive intraepidermal nerve fibers were significantly reduced in the pruritic compared with the non-lesional area (p < 0.05). In 32.3% of patients, radiological examinations showed a stenosis and in 47.7% a degeneration. A correlation between the radiological findings and the exact dermatomal localization of notalgia paraesthetica was found in 15.7% of the involved areas. The significant reduction in intraepidermal nerve fiber density suggests that damage to the peripheral nerves is a more important aetiological factor than spinal changes in notalgia paraesthetica.