Prurito en dermatología. Enfermedades y su tratamiento. Parte 2 / Pruritus in Dermatology: Part 2 — Diseases and Their Treatment

El prurito es el síntoma principal en múltiples enfermedades dermatológicas y sistémicas. La dermatitis atópica, la psoriasis, la dermatitis de contacto, la urticaria, el liquen simple crónico, la micosis fungoides, las cicatrices, las enfermedades autoinmunes, la enfermedad renal o hepática crónica, entre otras, asocian prurito que puede requerir un manejo terapéutico distinto. Aunque los antihistamínicos parecen ser la primera línea de tratamiento, en realidad su papel queda limitado a la urticaria y reacciones por fármacos, ya que los mecanismos fisiopatológicos de cada una de las entidades tratadas a lo largo de este manuscrito serán distintas. En estos últimos años han aparecido nuevas moléculas para el tratamiento del prurito, con perfiles de eficacia y seguridad muy atractivos para su uso en práctica clínica. Sin duda, es un momento crucial para el desarrollo de la dermatología en el campo del prurito, y una oportunidad para ser más exigentes con los objetivos a alcanzar en estos pacientes (AU)

Pruritus is the main symptom of many dermatologic and systemic diseases. Atopic dermatitis, psoriasis, contact dermatitis, urticaria, lichen simplex chronicus, mycosis fungoides, scars, autoimmune diseases, kidney or liver diseases among others are all associated with itch that may require different approaches to management. Although antihistamines seem to be the first line of therapy, in reality their role is limited to urticaria and drug-induced reactions. In fact, the pathophysiologic mechanisms of each of the conditions covered in this review will differ. Recent years have seen the emergence of new drugs whose efficacy and safety profiles are very attractive for the management of pruritus in clinical practice. Clearly we are at a critical moment in dermatology, in which we have the chance to be more ambitious in our goals when treating patients with pruritus (AU)

[Translated article] Pruritus in Dermatology: Part 2—Diseases and Their Treatment / Prurito en dermatología. Enfermedades y su tratamiento. Parte 2

Pruritus is the main symptom of many dermatologic and systemic diseases. Atopic dermatitis, psoriasis, contact dermatitis, urticaria, lichen simplex chronicus, mycosis fungoides, scars, autoimmune diseases, kidney or liver diseases among others are all associated with itch that may require different approaches to management. Although antihistamines seem to be the first line of therapy, in reality their role is limited to urticaria and drug-induced reactions. In fact, the pathophysiologic mechanisms of each of the conditions covered in this review will differ. Recent years have seen the emergence of new drugs whose efficacy and safety profiles are very attractive for the management of pruritus in clinical practice. Clearly we are at a critical moment in dermatology, in which we have the chance to be more ambitious in our goals when treating patients with pruritus (AU)

El prurito es el síntoma principal en múltiples enfermedades dermatológicas y sistémicas. La dermatitis atópica, la psoriasis, la dermatitis de contacto, la urticaria, el liquen simple crónico, la micosis fungoides, las cicatrices, las enfermedades autoinmunes, la enfermedad renal o hepática crónica, entre otras, asocian prurito que puede requerir un manejo terapéutico distinto. Aunque los antihistamínicos parecen ser la primera línea de tratamiento, en realidad su papel queda limitado a la urticaria y reacciones por fármacos, ya que los mecanismos fisiopatológicos de cada una de las entidades tratadas a lo largo de este manuscrito serán distintas. En estos últimos años han aparecido nuevas moléculas para el tratamiento del prurito, con perfiles de eficacia y seguridad muy atractivos para su uso en práctica clínica. Sin duda, es un momento crucial para el desarrollo de la dermatología en el campo del prurito, y una oportunidad para ser más exigentes con los objetivos a alcanzar en estos pacientes (AU)

Patterns among Patients with Chronic Pruritus: A Retrospective Analysis of 170 Patients.

Chronic pruritus profoundly affects patients' quality of life. The objective of this retrospective cross-sectional study was to characterize patients with chronic pruritus and identify patterns, in order to delineate a better diagnostic approach. Both semantic connectivity map and classical analysis were applied, linking demographic, clinical, laboratory and histopathological data with clinical and aetiological categories of 170 patients with chronic pruritus (median age 72 years, 58.2% women). The semantic map showed clinical categories separated in different hubs associated with distinct patterns concerning sex, aetiology, laboratory findings, and pharmacological treatment. Diabetes, diagnosis of cancer and psychiatric comorbidities were linked with certain clinical categories. Skin eosinophilia was a common finding of chronic pruritus, on both diseased and non-diseased skin. High frequencies of patients with chronic pruritus taking anti-arrhythmics, beta-blockers and AT-II receptor antagonists were noticed among those with underlying systemic, neurological and psychiatric diseases. This study provides a complex analysis of chronic pruritus and thus basic principles for a clinical work-up.

Position Statement: Linear prurigo is a subtype of chronic prurigo.

BACKGROUND: Chronic prurigo (CPG) is a distinct disease characterized by chronic pruritus, history and/or signs of prolonged scratching and multiple pruriginous lesions. It may present with various clinical manifestations, including papules, nodules, plaques or umbilicated lesions. Some patients with chronic pruritus show pruriginous linear and scaring scratch lesions (LSSL) and it is unclear whether these lesions belong to the spectrum of CPG. OBJECTIVE: To achieve a consensus on the classification of pruriginous LSSL and establish criteria to differentiate them from similar appearing conditions of different nature. METHODS: Members of the Task Force Pruritus (TFP) of the European Academy of Dermatology and Venereology participated in the consensus conference, discussing representative clinical cases. Using the Delphi method, consensus was reached when ≥75% of members agreed on a statement. RESULTS: Twenty-one members of the TFP with voting rights participated in the meeting. It was consented that LSSL occurs due to chronic pruritus and prolonged scratching, and share common pathophysiological mechanisms with CPG. LSSL were thus considered as belonging to the spectrum of CPG and the term 'linear prurigo' was chosen to describe this manifestation. CONCLUSION: Considering linear prurigo as belonging to the spectrum of CPG has important clinical implications, since both the diagnostic and therapeutic approach of these patients should be performed as recommended for CPG. Importantly, linear prurigo should be differentiated from self-inflicted skin lesions as factitious disorders or skin picking syndromes. In the latter, artificial manipulation rather than pruritus itself leads to the development of cutaneous lesions, which can show clinical similarities to linear prurigo.

Itch and psyche: psychiatric aspects of pruritus.

Itch, also referred to as pruritus, is an unpleasant cutaneous sensation provoking the desire to scratch. It is often an uncomfortable, subjective sensation responsible for decreased quality of life in a variety of psychodermatological conditions. Comorbid psychiatric conditions, including depression and anxiety, are frequently associated with itch and scratch cycle. The reciprocal and intricate relationship between the psyche and itch has been widely studied. The neurobiology of itch involves the complexity of specific mediators, itch-related neuronal pathways, and central processing of itch. The connection between itch and the psyche can be grouped under three headings: pruritic diseases with psychosocial sequelae, pruritic diseases aggravated by psychosocial factors, and psychiatric disorders causing pruritus. Itch and pain modulation go together in most circumstances and involve various substances including histamine, interleukins, protease-activated receptors, transient receptor potential receptors, opioids, and cannabinoids. The close interaction between keratinocytes and nerve endings modulating pain and itch also play a major role. Management of itch associated with its psychosomatic components is directed at an underlying cause and adopting a holistic approach to address not only dermatologic and somatosensory aspects, but also the cognitive, emotional, and psychosocial components. An integrated multidisciplinary team consisting of a dermatologist, psychiatrist, psychologist, and social worker is vital in addressing the multifaceted aspects of pruritus.

AMA Code of Medical Ethics' Opinions Related to a Physician's Power to Name.

The AMA Code of Medical Ethics offers guidance on ethical issues related to naming a condition via diagnosis. This article discusses 3 case examples that consider how the AMA Code can be applied.

Development of a core outcome set for therapeutic clinical trials enrolling dogs with atopic dermatitis (COSCAD'18).

BACKGROUND: For decades, the efficacy of interventions in clinical trials enrolling dogs with atopic dermatitis (AD) relied on heterogeneous evaluations of skin lesions and pruritus using unvalidated tools. Although some instruments for clinical signs were validated later, there was little impact on standardizing outcome measures resulting in difficulties in comparing treatment efficacy between trials and impeding meta-analyses. RESULTS: Participants in the Outcome Measures subcommittee of the International Committee of Allergic Diseases of Animals (ICADA) collaborated for two years to develop a core outcome set (COS) for canine AD, the COSCAD. This project involved several steps, constantly-re-assessed during online exchanges, to define the scope of this COS, to identify the relevant stakeholders, the domains to be evaluated, the instruments available for measuring agreed-upon domains and how to express outcome measures. This COSCAD'18 was designed principally for therapeutic-but not preventive or proactive-clinical trials enrolling dogs with chronic, nonseasonal (perennial), moderate-to-severe AD. Selected domains were skin lesions, pruritus manifestations and perception of treatment efficacy. Instruments to evaluate these domains were the CADESI4 or CADLI, the 10-point pruritus visual analog scale (PVAS10) and the Owner Global Assessment of Treatment Efficacy (OGATE), respectively. The COSCAD'18 has three outcome measures: the percentages of dogs with veterinarian-assessed skin lesions or owner-rated pruritus manifestation scores in the range of normal dogs or those with mild AD; the third is a good-to-excellent global assessment by the pet owners of their perception of treatment efficacy. Importantly, this COSCAD'18 is not meant to represent the sole-or primary-outcome measures evaluated in a trial; authors are always free to add any others, which they deem will best assess the efficacy of tested interventions. Benchmarks to define a threshold for treatment success were not set, as what constitutes a clinically-relevant therapeutic efficacy is expected to vary greatly depending interventions. CONCLUSIONS: This COSCAD'18 should help veterinarians and owners compare the benefits of treatments in future trials. This COS should also facilitate the combination of trial results in future systematic reviews, thereby producing more reliable summary estimates of treatment effects and enhancing evidence-based veterinary dermatology.

Pruritus: Progress toward Pathogenesis and Treatment.

Pruritus, the most common cutaneous symptom, is widely seen in many skin complaints. It is an uncomfortable feeling on the skin and sometimes impairs patients' quality of life. At present, the specific mechanism of pruritus still remains unclear. Antihistamines, which are usually used to relieve pruritus, ineffectively work in some patients with itching. Recent evidence has suggested that, apart from histamine, many mediators and signaling pathways are involved in the pathogenesis of pruritus. Various therapeutic options for itching correspondingly have been developed. In this review, we summarize the updated pathogenesis and therapeutic strategies for pruritus.

Diagnostic Work-up of the Itchy Patient.

Pruritus is a common and troubling symptom associated with many dermatologic, systemic, neurologic, or psychiatric disorders. This article reviews the current understanding of the pathogenesis of itch and offers a differential diagnosis for the causes of chronic pruritus. The article discusses key diagnostic steps and considerations when evaluating patients with chronic pruritus.

Psychogenic itch.

Psychogenic itch can be defined as "an itch disorder where itch is at the center of the symptomatology and where psychological factors play an evident role in the triggering, intensity, aggravation, or persistence of the pruritus." The disorder is poorly known by both psychiatrists and dermatologists and this review summarizes data on psychogenic itch. Because differential diagnosis is difficult, the frequency is poorly known. The burden is huge for people suffering from this disorder but a management associating psychological and pharmacological approach could be very helpful. Classification, psychopathology, and physiopathology are still debating. New data from brain imaging could be very helpful. Psychological factors are known to modulate itch in all patients, but there is a specific diagnosis of psychogenic itch that must be proposed cautiously. Neurophysiological and psychological theories are not mutually exclusive and can be used to better understand this disorder. Itch can be mentally induced. Opioids and other neurotransmitters, such as acetylcholine and dopamine, are probably involved in this phenomenon.

The effect of Aloe vera gel and sweet almond oil on striae gravidarum in nulliparous women.

BACKGROUND AND OBJECTIVE: Striae are linear depressions of the skin and causes psychological and sexual problems in person. Different methods are used to prevent and treat them but there is no definitive method. We compared the effect of Aloe vera gel and sweet almond oil on striae gravidarum. MATERIALS AND METHODS: In this double-blind clinical trial, 160 nulliparous women were enrolled and randomly divided into three case groups and one control group. The four groups were given 700 g Aloe vera, sweet almond oil, and base cream to use topically on the abdominal skin and forth group don't receive any medication as control group in five steps, they were examined study's variables (itching, erythema, and spread of striae) using statistical tests in SPSS. RESULT: The findings showed that Aloe vera and sweet almond oil creams are more effective than the base cream and the control group to decrease itching and erythema and to prevent the spread of striae on the surface of abdomen (p < .05); however, all three creams had a similar effect on the diameter and the number of striae (p > .05). CONCLUSIONS: Aloe vera and sweet almond oil creams reduce the itching of striae and prevent their progression.

Classification of Itch.

Chronic pruritus has diverse forms of presentation and can appear not only on normal skin [International Forum for the Study of Itch (IFSI) classification group II], but also in the company of dermatoses (IFSI classification group I). Scratching, a natural reflex, begins in response to itch. Enough damage can be done to the skin by scratching to cause changes in the primary clinical picture, often leading to a clinical picture predominated by the development of chronic scratch lesions (IFSI classification group III). An internationally recognized, standardized classification system was created by the IFSI to not only aid in clarifying terms and definitions, but also to harmonize the global nomenclature for itch.

Paraneoplastic itch: an expert position statement from the Special Interest Group (SIG) of the International Forum on the Study of Itch (IFSI).

In clinical practice, the term "paraneoplastic itch" is used to describe itch in patients with cancer. Patients with hematological or solid tumor malignancies can be affected. In general, paraneoplastic itch is considered a rare disorder. However, paraneoplastic itch in hematological malignancies such as polycythemia vera and lymphoma are relatively frequent while other forms of paraneoplastic itch are in fact extremely rare. The true frequency of this symptom is unclear, epidemiological data in this field are limited. Itch in malignant disease may additionally impair patients' quality of life. A population-based cohort study showed that chronic itch without concomitant skin changes is a risk factor for having undiagnosed hematologic and bile duct malignancies. Paraneoplastic itch is rather resistant to treatment. In 2012, an interdisciplinary interest group of physicians and researchers was founded, aiming to generate a clear definition of paraneoplastic itch. In this paper we briefly review the current knowledge and aim to define what can be summarized under the term "paraneoplastic itch".

[Prurigo. Clinical definition and classification]. / Prurigo. Klinische Definition und Klassifikation.

BACKGROUND: There is no consistent definition of the term prurigo and a clear classification is unavailable. OBJECTIVES: Definition of the current forms of prurigo and a new approach to a specific classification. METHODS: Review of the types of prurigo as presented in current textbooks and publications. RESULTS: Pruritus is the main symptom of prurigo and shows an intensely pruritic papule or nodule as the main efflorescence. The term prurigo is not only used for secondary lesions, but also for primary dermatoses. The different forms of prurigo obtain their names depending on etiology, onset and duration of lesions or the clinical appearance. CONCLUSIONS: The term prurigo has not been used consistently. A revision of the classification with a clear distinction between primary dermatoses and secondary lesions seems reasonable. In secondary prurigo, a clinical classification and the cause should be mentioned.

Current concepts of pathophysiology, epidemiology and classification of pruritus.

Discovery of pruritus-specific mediators and receptors facilitated the neurobiological concept of pruritus: itch-specific (histamine-dependent and histamine-independent C-fibers); itch-specific receptors on cutaneous and spinal neurons; "dialogue" between the pruritus-specific neurons and cells in the skin; peripheral and central mediation of pruritus; functional "pruritus-specific matrix" in the brain with a role of pruritus center. In 10%-50% of persons without skin diseases, pruritus is considered the manifestation of a systemic disorder. Identification of pruritus within autoimmune and inflammatory diseases in dermatology is based on the clinical picture and nature of the underlying disease, implying the development of pruritus on primarily and/or secondarily inflamed skin. In the internal medicine, pruritus commonly presents on primarily non-inflamed skin., involvement of the skin and gastrointestinal tract are two independent risk factors of pruritus in systemic sclerosis, and of anal/vulvar pruritus. Classification combines etiological and clinical criteria and should be considered the only segment of a comprehensive approach to pruritus of unknown origin.

Similarities between neuropathic pruritus sites and lichen simplex chronicus sites.

BACKGROUND: Localized itch of non-pruritoceptive origin is often neuropathic and may be referred to as neuropathic itch syndrome. OBJECTIVES: To describe the results of nerve conduction studies in patients with anogenital pruritus, brachioradial pruritus and scalp dysesthesia, and compare these sites to typical sites of lichen simplex chronicus (LSC). METHODS: The study summarizes previously published data combined with unpublished data of patients with scalp dysesthesia. Nerve conduction studies included measurements of distal sensory and motor latency, conduction velocity and F-responses. RESULTS: A neuropathy was demonstrated in 29 of 36 patients with anogenital pruritus (80.5%), 8/14 with brachioradial pruritus (57.1%) and 4/9 with scalp dysesthesia (44.4%). The typical sites overlapped with some but not all LSC sites. CONCLUSIONS: A considerable proportion of patients with brachioradial pruritus, anogenital pruritus and scalp dysesthesia have abnormal nerve conduction findings, suggesting a neuropathic origin. The skin sites overlap with some common LSC sites, suggesting that in some cases of LSC a local neuropathy could be a possible cause.

Validation of the Canine Atopic Dermatitis Extent and Severity Index (CADESI)-4, a simplified severity scale for assessing skin lesions of atopic dermatitis in dogs.

BACKGROUND: Severity scales are used to grade skin lesions in clinical trials for treatment of dogs with atopic dermatitis (AD). At this time, only two scales have been validated, namely the Canine Atopic Dermatitis Extent and Severity Index (CADESI)-3 and the Canine Atopic Dermatitis Lesion Index (CADLI). However, the high number of assessed sites makes the CADESI-3 impractical. HYPOTHESIS/OBJECTIVES: The aim of this study was to develop and validate a fourth version of the CADESI that is simpler and quicker to administer. METHODS: Body sites, lesions and severity grades were revised by members of the International Committee on Allergic Diseases of Animals (ICADA). The newly designed CADESI-4 was tested for its validity (i.e. content, construct and criterion), reliability (i.e. inter- and intra-observer reliability and internal consistency), responsiveness (i.e. sensitivity to change) and time to administer. Disease severity benchmarks were chosen using receiver operating characteristic methodology. RESULTS: The CADESI-4 was simplified in comparison to its previous version to comprise 20 body sites typically affected in atopic dogs. Three lesions (erythema, lichenification and alopecia/excoriation) were scored from 0 to 3 at each site. The CADESI-4 had satisfactory validity, reliability and sensitivity to change. On average, the time to administer a CADESI-4 was one-third that of a CADESI-3. Proposed benchmarks for mild, moderate and severe AD skin lesions are 10, 35 and 60, respectively. CONCLUSIONS AND CLINICAL IMPORTANCE: The CADESI-4 is simpler to use and quicker to administer than its previous version. The ICADA recommends the CADESI-4 instead of the CADESI-3 to score skin lesions of AD in dogs enrolled in clinical trials.