Disease modification in chronic spontaneous urticaria.

Chronic spontaneous urticaria (CSU) is a debilitating, inflammatory skin condition characterized by infiltrating immune cells. Available treatments are limited to improving the signs and symptoms. There is an unmet need to develop therapies that target disease-driving pathways upstream of mast cell activation to inhibit or delay the progression of CSU and associated comorbidities. Here, we aim to define disease modification due to a treatment intervention and criteria that disease-modifying treatments (DMTs) must meet in CSU. We have defined disease modification in CSU as a favorable treatment-induced change in the underlying pathophysiology and, therefore, the disease course, which is clinically beneficial and enduring. A DMT must fulfil the following criteria: (1) prevents or delays the progression of CSU, (2) induces long-term, therapy-free clinical remission, which is the sustained absence of CSU signs and symptoms without the need for treatment, and (3) affects the underlying mechanism of CSU, as demonstrated by an effect on disease-driving signals and/or a biomarker. DMTs in CSU should slow disease progression, achieve long-lasting disease remission, target disease-driving mechanisms, reduce mast cell-activating IgE autoantibodies, target cytokine profile polarization, and normalize the gut microbiome and barrier. Treating CSU at the immune system level could provide valuable alternatives to pharmacotherapy in CSU management. Specific DMTs in CSU are yet to be developed, but some show potential benefits, such as inhibitors of Bruton's Tyrosine Kinase, IL-4 and IL-13. Future therapies could prevent CSU signs and symptoms, achieve long-term clinical benefits after discontinuing treatment, and prevent associated concomitant disorders.

New insights into chronic inducible urticaria.

PURPOSE OF REVIEW: Chronic inducible urticaria (CIndU) is a group of long-persisting and challenging to manage diseases, characterized by recurrent wheals and angioedema induced by definite triggers. In this review, we address recent findings on CIndU pathogenesis, diagnosis as well as its treatment, and we discuss novel potential targets that may lead to the development of more effective therapies for CIndU patients. RECENT ADVANCES: Meaningful advances in the understanding of its pathogenesis have been reported in the last decades. Novel CIndU-specific patient-reported outcome measures enable a closer and better evaluation of patients. CIndU is a hard-to-treat disease that highly impairs quality of life (QoL) of affected patients. Provocation tests allow to diagnose CIndU subtypes. The only licensed and recommended treatment for CIndU are second generation non-sedating H1-antihistamines, which lack efficacy in many cases. Omalizumab off-label use has been assessed in all types of CIndU with overall good outcomes. Promising emerging therapies currently assessed in chronic spontaneous urticaria are paving the path for novel treatments for CIndU.

[Chronic brachioradial pruritus in cervical spine meningioma]. / Chronischer brachioradialer Pruritus bei spinalem Meningeom.

We report a case of a 57-year-old slightly obese woman with localized itch on the arms accompanied by stinging and burning sensations. A few excoriations were observed upon clinical examination. The MRI examination of the cervical spine revealed a meningioma at C5/C6 level. The diagnosis of brachioradial pruritus due to compression of the cervical myelon was further supported by a positive ice-pack sign. Disc herniation or prolapse, foraminal stenosis and degenerative alterations constitute other possible causes of brachioradial pruritus.

Chronic Pruritus of Unknown Origin: Clinical Profile and Disease-Related Burden.

Chronic pruritus of unknown origin is established when no underlying origin for pruritus can be determined. This retrospective cohort study aimed to determine the clinical profile and disease-related burden of chronic pruritus of unknown origin. A total of 263 patients (female/male: 154/109, median age 55 years) were included. Moderate to severe itch intensities were recorded (median average itch: 5.5/10, n = 200; median worst itch: 7.5/10, n = 199). In most cases pruritus lasted longer than 1 year (77.6%), occurred daily (68.2%), occurred in attacks (72.8%), and was often accompanied by dysaesthesias, such as burning, tingling and stinging. Quality of life was moderately impaired, while 22.2% and 12.4% of patients showed pathological anxiety and depression scores. Scratch lesions were associated with higher intensities of itch and greater impairment of quality of life, while women were more burdened by the disease than men. Chronic pruritus of unknown origin may occur at any age and the majority of patients endure severe itch with substantial disease-related burden.

Hand Pruritus: Clinical Profile, Functional Impairment and Disease-related Burden in a Prospective Cohort Study of 395 Patients.

Human hands are complex structures essential for a variety of functions in everyday life. This study prospectively investigated the clinical features of hand pruritus and the resulting functional impairment and disease-related burden in 395 patients with chronic pruritus (210 females, median age 59 years). Moderate to very severe hand pruritus was reported by 91.2% of patients, while 79% perceived additional sensory symptoms, such as burning, pain or tingling. A long duration of pruritus occurred in most cases (>6 months: 71.4%). A considerable proportion of patients showed moderate to severe impairment in the use of their hands (40.2%), performance of daily activities (65.0%) and quality of life (45.2%). Disease severity and burden is particularly high when both the palms and the backs of the hands are affected, and when pain is present simultaneously. Pruritus located on the hands is impairing and burdensome due to the functional relevance of the hands in everyday life.

Investigator's Global Assessment of Chronic Prurigo: A New Instrument for Use in Clinical Trials.

Chronic prurigo is a pruritic disease characterized by the development of pruriginous lesions due to scratching. The number of lesions is representative of the stage of the disease, while the presence of excoriations reflects the scratching activity. Aim of this study was to validate a new developed tool for the objective assessment of chronic prurigo. Investigator's Global Assessment scales for stage and activity were completed for 187 patients with chronic prurigo, who also reported patient-reported outcomes for itch intensity and quality of life. To assess the reliability and objectivity of the Investigator's Global Assessment, 5 independent raters completed the Investigator's Global Assessment scales for 8 patients twice. The scores increased with increased intensity of pruritus. The Investigator's Global Assessment stage scales correlated strongly with each other (Kendall's-tau-b 0.62) and moderately with the Investigator's Global Assessment activity scale (Kendall's-tau-b 0.47). Intra-rater test-retest reliability was excellent for all items, while the congruence among raters was very good for Investigator's Global Assessment - chronic prurigo activity (Kendall's W 0.84) and good for Investigator's Global Assessment stage scales (Kendall's W 0.747). Investigator's Global Assessment - chronic prurigo stage and activity are thus the best Investigator's Global Assessment instruments for use in assessing chronic prurigo.

Chronic Nodular Prurigo: A European Cross-sectional Study of Patient Perspectives on Therapeutic Goals and Satisfaction.

Chronic nodular prurigo is characterized by recalcitrant itch. Patient perspectives on therapeutic goals, satisfaction with therapy and efficacy of therapeutic regimens for this condition are unknown. This questionnaire study examined these issues in 406 patients with chronic nodular prurigo from 15 European dermatological centres. Improvements in itch, skin lesions and sleep were the most important goals. Emollients, topical corticosteroids and antihistamines were the most frequently used treatments, while a minority of patients were prescribed potent medications, such as systemic immunosuppressants and gabapentinoids. Most patients were not satisfied with their previous therapy (56.8%), while 9.8% did not receive any therapy despite having active disease. A substantial number of respondents (28.7%) considered none of the therapeutic options effective. Although chronic nodular prurigo is a severe disease, most patients were not treated with potent systemic drugs, which may contribute to the high levels of dissatisfaction and disbelief in available therapies. Specific guidelines for chronic nodular prurigo and the development of novel therapies are necessary to improve care.

Analysis of 325 Patients with Chronic Nodular Prurigo: Clinics, Burden of Disease and Course of Treatment.

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.

Challenges in Clinical Research and Care in Pruritus.

Chronic pruritus is a frequent global condition. The pathophysiology, underlying aetiology, clinical manifestation, associated burden and response to therapy of chronic pruritus varies from patient to patient, making clinical research and management of this condition challenging. There are still several unmet needs, such as the need to standardize translational research protocols, diagnostic and therapeutic procedures and to enhance the knowledge of the humanistic and economic burden associated with chronic pruritus. Basic and clinical research is of the utmost importance to target these matters. Clinical research has the potential to identify new relevant mechanisms in affected patients, which may lead to identification of novel therapy targets. This article discusses in depth current shortcomings in the daily care of patients with chronic pruritus and the challenges clinical researchers and physicians treating chronic pruritus face in addressing these matters.

[Therapy for chronic pruritus-light at the end of a long tunnel?] / Arzneitherapie des chronischen Pruritus ­ Licht am Ende des langen Tunnels?

Chronic pruritus (CP) is a highly prevalent, difficult-to-treat, and burdensome condition. Today, multiple topical and systemic therapy concepts are available for the treatment of CP. Current guidelines recommend, besides topical treatments, the use of a vast array of mostly off-label systemic drugs with different mechanisms, including antihistamines, gabapentinoids, antidepressants, immunosuppressive drugs, and µ­opioid receptor antagonists. The choice of the right agent depends on the indication, the safety profile of the drug, and patient-specific features, such as comorbidities and comedication. Thanks to a deeper understanding of the pathophysiology of CP, novel drugs have been developed and have already shown antipruritic efficacy in clinical studies and case reports. Of note, phosphodiesterase­4 inhibitors as topical agents and monoclonal antibodies, neurokinin­1 receptor antagonists, Janus kinase inhibitors, and opioid receptor modulators as systemic agents are in the frontline of innovative CP treatment. Other promising targets include structures of the peripheral and central nervous system which are involved in itch signaling. This article provides an overview of currently available topical and systemic therapies for CP and their indications and discusses novel innovative agents and promising new targets in CP.

How to define chronic prurigo?

Chronic prurigo impairs quality of life and is immensely challenging to treat. Until recently, no clear definition or classification system was available for this disease. A European task force specialized in pruritus defined chronic prurigo as a distinct disease characterized by chronic pruritus, a lengthy scratching behaviour and the presence of pruriginous lesions. Papular, nodular, plaque, umbilicated and linear prurigo were identified as clinical subtypes according to the most prominent lesion type observed in the physical examination. Various clinical and pathophysiological aspects, which are common across the range of clinical manifestations of chronic prurigo, argue for chronic prurigo as a disease in its own right. Chronic prurigo should be clearly demarcated from other conditions such as so-called acute or subacute prurigo forms as well as from psychogenic self-inflicted skin lesions, since different diagnostic criteria apply for these diseases. This viewpoint essay provides a detailed definition and classification of chronic prurigo including its obligatory and associated diagnostic criteria and discusses chronic prurigo as a distinct disease as well as the demarcation to other relevant conditions.

Selective Nerve Fibre Activation in Patients with Generalized Chronic Pruritus: Hint for Central Sensitization?

Central sensitization induces pain augmentation in chronic pain states. An analogous mechanism is speculated for chronic pruritus. This study compared patients with chronic pruritus (n = 79) of different origins (atopic dermatitis, chronic pruritus on non-lesional skin, chronic prurigo) and healthy controls (HC, n = 54) with regard to itch intensity and qualities of sensory symptoms after selective peripheral nerve fibre activation by electrical stimulation at 5 Hz (surrogate for C-fibre function) and 2,000 Hz (surrogate for Aß-fibre function) using a Neurometer®. Electrically-induced itch was more intense in patients with chronic pruritus than in HC, but patients with chronic pruritus did not report "itch" more often than HC at 5 Hz. Stimulation at 2,000 Hz induced more pricking and tingling, but less throbbing in patients with chronic pruritus compared with HC. Treatment with cooling compound reduced clinical and experimental itch, but did not alter the distribution of sensory symptoms. These data show hyperknesis in chronic pruritus of various origins, arguing for common central sensitization mechanisms.

Sensory Qualities Point to Different Structural and Functional Skin Patterns in Chronic Pruritus Patients. A Translational Explorative Study.

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.

Ethnic differences and comorbidities of 909 prurigo nodularis patients.

BACKGROUND: Prurigo nodularis (PN) is a poorly understood, understudied pruritic dermatosis that reduces quality of life. OBJECTIVE: To characterize the demographics and comorbidities associated with PN. METHODS: Cross-sectional study of patients 18 years and older who were seen at the Johns Hopkins Health System between December 6, 2012, and December 6, 2017. RESULTS: Over the past 5 years, 909 patients with PN were seen at Johns Hopkins Health System. African American patients were 3.4 times more likely to have PN than white patients were (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.9-3.9; P < .001). A comparison of the study patients and race-matched controls revealed that PN was significantly associated with a variety of systemic, cardiovascular, and psychiatric comorbidities, including chronic kidney disease, chronic hepatitis C, chronic obstructive pulmonary disease, congestive heart failure, depression, and atopic dermatitis. Black patients with PN were 10.5 times more likely (OR, 10.5; 95% CI, 7.9-13.9; P < .001) to have HIV than were race-matched controls with atopic dermatitis, and 8 times more likely (OR, 8.0; 95% CI, 5.7-11.1; P < .001) to have HIV than were African American patients with psoriasis. LIMITATIONS: Our data describe patients seen by 1 hospital system. Our data identify associated conditions and comorbidities but are unable to support a causal relationship. CONCLUSION: PN disproportionately affects African Americans and is associated with several systemic conditions, including HIV, chronic kidney disease, and diabetes.

Brachioradial Pruritus and Notalgia Paraesthetica: A Comparative Observational Study of Clinical Presentation and Morphological Pathologies.

Brachioradial pruritus (BRP) and notalgia paraesthetica (NP) represent 2 of the most common neuropathic itch syndromes. A total of 58 consecutive patients presenting at the Center for Chronic Pruritus, University Hospital Münster, were analysed with regard to clinical presentation, anatomical and morphological pathologies, impairment in quality of life, and response to treatment with topical capsaicin. Patients with BRP reported stinging and burning more often than those with NP. In the BRP group structural magnetic resonance imaging abnormalities more frequently correlated with localization of the symptoms compared with in patients with NP. In addition, intraepidermal nerve fibre density was decreased in lesional skin in patients with BRP, but not in those with NP, confirming the neuropathic origin in BRP. Topical capsaicin resulted in a significantly higher alleviation of itch and pain intensity and improvement in quality of life in patients with BRP compared with those with NP, which may reflect clinical and aetiological differences between the conditions.

There is no functional small-fibre neuropathy in prurigo nodularis despite neuroanatomical alterations.

Prurigo nodularis (PN) is a pruritic condition with altered epidermal neuroanatomy as demonstrated previously. Here we elucidated neuroimmunological mechanisms by combining functional, morphological and gene expression experiments in twelve subjects with PN and eight healthy controls. Subjects with PN showed a reduced intra-epidermal nerve fibre density (IENFD) in lesional skin. Quantitative sensory testing indicated maintenance of somatosensory function compared to controls. None of the tested molecular markers including the neuron-distracting SEMA3A and neuron-attracting NGF were altered in lesional vs non-lesional skin in PN subjects. Accordingly, we speculate that scratching may contribute to reduced IENFD rather than an authentic endogenous neuropathy.