S2k-Leitlinie zur Diagnostik und Therapie des chronischen Pruritus - Update - Kurzversion

[Geriatric dermatology]

BACKGROUND

With an ageing society the incidences of skin diseases increase.

OBJECTIVE

The most important skin diseases in geriatric patients are discussed.

MATERIAL AND METHODS

A literature search was conducted using the PubMed database and standard dermatological textbooks.

RESULTS

Skin diseases in geriatric patients are often more susceptible to external influences and can be affected by visceral diseases. Due to a delayed diagnosis, malignant skin diseases in geriatric patients are first diagnosed at a higher stage.

CONCLUSION

Physiological skin changes are to be treated with appropriate care. In the case of unclear skin changes, a timely dermatological check-up is to be done.

[Update on the treatment of chronic prurigo]

Chronic prurigo is an inflammatory dermatosis defined by the presence of chronic pruritus and single to multiple symmetrically distributed pruriginous lesions such as nodules, papules, and plaques. Various dermatological, systemic, neurological, and/or psychiatric diseases are associated with chronic prurigo. The care of these patients is very complex due to the multifactorial character and also because of the sometimes very pronounced consequences such as an impairment of quality of life with sleep disorders. Furthermore, there are no approved therapies. The current guideline-based treatment recommendations include topical application of steroids, capsaicin, calcineurin inhibitors, phototherapy, and systemic use of gabapentinoids, μ‑opioid receptor antagonists, immunosuppressants, or dupilumab. Results from randomized controlled trials and case series on new therapies including biologics (e.g., nemolizumab) and Janus kinase inhibitors are promising. This article provides an overview of currently available treatment options and discusses the latest data on the efficacy of future therapies.

Comparison of Epidermal Barrier Integrity in Adults with Classic Atopic Dermatitis, Atopic Prurigo and Non-Atopic Prurigo Nodularis

A deficient epidermal barrier is a key feature of atopic dermatitis (AD) and comprises altered lipid and protein content and composition of the stratum corneum resulting in disturbed water balance. Clinically, eczematous lesions on dry skin and pruritus develop. Pruritic nodules occur in prurigo nodularis (PN), another chronic skin disease, which can be associated with atopy. We aimed at comparing the three clinical pictures, classic AD, atopic prurigo (AP), and non-atopic PN, to healthy controls regarding the epidermal barrier. We determined clinical parameters and performed biophysical measurements, histology/immunohistochemistry, electron microscopy, and molecular biological analysis. We found distinctively elevated clinical scores, reduced hydration and increased transepidermal water loss, epidermal hyperplasia and inflammation reduced filaggrin and increased loricrin and involucrin expression, as well as reduced intercellular lipid lamellae in all three disease groups. These findings show a severe disruption in epidermal barrier structure and function in all three disorders so that epidermal barrier impairment is now proven not only for AD but also for PN.

[Chronic brachioradial pruritus in cervical spine meningioma]

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.

Skin Lesions, Skin Care, and Characteristics of Pruritus in Patients Undergoing Haemodialysis

INTRODUCTION

Pruritus has been shown to be a common and burdensome complaint in the general population. In some diseases, there is an even higher rate and intensity of pruritus such as in chronic kidney diseases. In particular, patients requiring dialysis commonly suffer from pruritus with proportions between 22.0 and 90.0%. Few data on the characteristics and burden of such pruritus have been published. Therefore, the aim of this study was to investigate the extent and profiles of pruritus in such patients related to skin lesions and care.

METHODS

A non-interventional cross-sectional study in 14 centres for haemodialysis across Germany was conducted. The survey explored the prevalence, severity, and resulting burden of pruritus and skin lesions.

RESULTS

In total, 302 patients with uraemia (56.5% male, mean age 66.0 ± 14.4 years, mean duration of dialysis 3.9 ± 4.8 years) were included. Skin lesions appeared since start of dialysis in 50.0% of patients, with xerosis (94.7%) and desquamation (25.8%) being the most frequent and disturbing findings. Pruritus was reported by 60.9% of patients undergoing dialysis with a current mean numerical rating scale of 5.1 ± 2.4 occurring most frequently in the back, legs, and arms. About 89.0% of patients with xerosis and 69.0% with desquamation reported self-medication. However, only 40.0% and 28.0% sought medical help, respectively, indicating a remarkable lack of healthcare.

DISCUSSION

The current data suggest a more intensive focus on the skin symptoms and signs related to uraemia in the patients with dialysis and thus underline claims from a previous German large-scale study. Recommendations for early treatment and prevention of skin lesions in dialysis patients should be developed. Further research should be conducted focusing on recognizing subgroups of patients of particular vulnerability to pruritus and skin lesions, which may facilitate identifying patients at risk in an early moment. Moreover, a more specific tool for screening of skin lesions as well as pruritus may be useful since the existing instruments lack such specificity.

Neuropathic Itch: Routes to Clinical Diagnosis

Neuropathic itch occurs due to damage of neurons of the peripheral or central nervous system. Several entities, including metabolic, neurodegenerative, orthopedic, infectious, autoimmune, malignant, and iatrogenic conditions, may affect the somatosensory system and induce neuropathic itch. Due to the complex nature of neuropathic itch, particularly concerning its clinical presentation and possible etiological factors, diagnostic work-up of this condition is challenging. A detailed medical history, especially in regard to the itch, and a comprehensive physical examination are relevant to detect characteristic signs and symptoms of neuropathic itch and to rule out other possible causes for chronic itch. Complementary diagnostic exams, especially laboratory tests, determination of the intraepidermal nerve fiber density via a skin biopsy and radiological examinations may be indicated to confirm the diagnosis of neuropathic itch and to identify underlying etiological factors. Functional assessments such as quantitative sensory testing, nerve conduction studies, evoked potentials, or microneurography may be considered in particular cases. This review article provides a comprehensive overview of the diagnostic work-up recommended for patients with neuropathic itch.

Pathophysiology and Treatment of Pruritus in Elderly

Pruritus is a relatively common symptom that anyone can experience at any point in their life and is more common in the elderly. Pruritus in elderly can be defined as chronic pruritus in a person over 65 years old. The pathophysiology of pruritus in elderly is still unclear, and the quality of life is reduced. Generally, itch can be clinically classified into six types: Itch caused by systemic diseases, itch caused by skin diseases, neuropathic pruritus, psychogenic pruritus, pruritus with multiple factors, and from unknown causes. Senile pruritus can be defined as a chronic pruritus of unknown origin in elderly people. Various neuronal mediators, signaling mechanisms at neuronal terminals, central and peripheral neurotransmission pathways, and neuronal sensitizations are included in the processes causing itch. A variety of therapies are used and several novel drugs are being developed to relieve itch, including systemic and topical treatments.

Vulvar pruritus-Causes, Diagnosis and Therapeutic Approach

BACKGROUND

In Germany, 17-23% of the population suffers from chronic itching of the skin; in 5-10% of cases, the female genitalia are affected, specifically, the vulva. Vulvar pruritus is thus a common symptom that often markedly impairs the affected women's quality of life.

METHODS

This review is based on pertinent publications that were retrieved by a selective search in MEDLINE/PubMed for articles on the pathogenesis, diagnosis, and treatment of vul- var pruritus. The search terms were (in German and English) "vulvärer Juckreiz," "pruritus vulvae," and "genital itch," alone and in combination with "Behandlung," "Therapie," or "treat- ment."

RESULTS

The most common cause of vulvar pruritus is vulvo- vaginal candidiasis followed by chronic dermatoses, such as lichen sclerosus and vulvar eczema. Especially in refractory cases, an invasive or preinvasive lesion such as squamous epithelial dysplasia (VIN, vulvar intraepithelial neoplasia) should be borne in mind in the differential diagnosis. Rarer causes include infection, atrophy, and vulvodynia. The essen- tial elements of treatment are topical/oral antimycotic drugs and high-potency glucocorticoids, along with consistently ap- plied, basic moisturizing care and the avoidance of potential triggering factors.

CONCLUSION

As vulvar pruritus has multiple causes, standard- ization of its diagnostic evaluation and treatment would be l efficacy and to meet the diverse needs of women who suffer from this condition.

Generalized chronic itch induced by small-fibre neuropathy: clinical profile and proposed diagnostic criteria

BACKGROUND

Small-fibre neuropathy (SFN) is a known cause for pain, however, it may be also associated with chronic itch. The clinical profile of chronic itch due to SFN is poorly defined and accordingly under-diagnosed in clinical care.

OBJECTIVES

To establish the clinical profile of patients with SFN and to propose diagnostic criteria for this patient population.

METHODS

Clinical data from patients diagnosed with SFN [chronic generalized itch and reduced intraepidermal nerve fibre density (IENFD)] were analysed retrospectively.

RESULTS

A total of 142 patients (60 females, median age: 62.5 years) were included. Patients reported daily, moderate to severe itch intensity scores occurring mostly in attacks (62.5%). Only 11 patients experienced exclusively itch, while the remaining patients (92%) reported pruralgia (itch along with painful sensations). Burning (50%), a sensation like needle pricks (46%) and tingling (45%) were the sensory symptoms reported by most patients. Cold or ice application led to an alleviation of the symptoms. The IENFD did not correlate with itch intensity; however, patients with a severely reduced IENFD (<30% of the normative cut-off value) reported more frequently sharp, spiky and drilling sensations compared to the remaining patients. The quality of life was moderately impaired and correlated with itch intensity, whereas anxiety and depression scores were low.

CONCLUSIONS

Onset of pruralgia on normal appearing skin, occurrence in attacks and symptomatic alleviation with cold/ice application should alert physicians for a possible neuropathic SFN-related origin of itch. A reduced IENFD can confirm the diagnosis of SFN.

[Supportive therapy and management of side effects in dermato-oncology]

In the context of supportive therapy, possible complaints which may be caused by the cancer itself, by the antitumoral therapy or by psychosocial concerns are considered. Due to the introduction of new anticancer drugs in dermato-oncology, clinicians are confronted with a novel spectrum of adverse events. There are a number of inflammatory, immune-mediated side effects caused by immunotherapies, which can affect virtually any organ. Targeted therapies also have specific side effects. Basically, the management of adverse events depends on their severity. Besides treatment breaks and dosage modifications, immunotherapy-related adverse events are treated with systemic immunosuppressants. Supportive symptomatic therapy is offered. The additional consideration of psychosocial problems can improve quality of life of cancer patients.

Characterization of cowhage-induced pruritus in inflamed and non-inflamed skin

BACKGROUND AND OBJECTIVE

Pruritus is a major symptom of many inflammatory diseases and impacts greatly the quality of life in patients. We aimed to specify the characteristics of experimentally induced pruritus in normal skin and in experimentally induced inflammatory dermatitis in healthy volunteers.

METHODS

Skin inflammation was induced by the repeated application of sodium lauryl sulphate (SLS 2%) on the volar forearms of 30 healthy volunteers. Inflammatory dermatitis intensity was assessed using the eczema score adapted from Frosch and Kligman. Non-histaminergic pruritus was induced by cowhage spicules rubbed on the volar forearms and recorded for 30 min on a 10-cm visual analogue scale (VAS) in both non-inflamed and inflamed skin.

RESULTS

Induction of inflammatory dermatitis by SLS resulted in a mild inflammatory dermatitis with an inflammation score of 2.3 ± 0.1 within 7 days of treatment. Cowhage-induced pruritus was of markedly higher intensity (P < 0.001), and all but two individuals had higher maximum pruritus intensity in inflamed skin as compared to non-inflamed skin, whereas the kinetics of the pruritus response were similar. The quality of cowhage-induced pruritus was significantly different with more 'burning' and 'painful sensations' in inflamed skin (P < 0.01). Maximum pruritus intensity in inflamed skin strongly correlated with maximum pruritus intensity in non-inflamed skin (r = 0.51, P = 0.004). Skin hydration, skin barrier integrity and dermatitis severity did not correlate with pruritus intensity.

CONCLUSION

Taken together, pruritus in inflamed skin is perceived as more intense, painful and burning. This may explain, in part, why pruritus is a major driver of quality-of-life impairment in patients with chronic inflammatory skin conditions such as atopic dermatitis.

[New findings regarding the neurobiology of pruritus]

Chronic pruritus may arise from different conditions, including dermatological, systemic, neurologic, psychiatric, and psychosomatic diseases, leading to a substantial decrease in the quality of life of affected patients. The neurobiological mechanisms involved in chronic pruritus are not yet fully understood. However, in recent years important achievements have been made in this regard. This article aims to provide an overview of the current understanding of these mechanisms. The complex network of neurons, keratinocytes, inflammatory cells, cytokines, and neurotrophic factors which play a role in the development and maintenance of chronic pruritus are highlighted, as well as the pruritogens involved in pruritic diseases in humans. Additionally, the importance of neuropathy and scratch-induced changes for the pathophysiology of chronic pruritus are discussed. The new findings on the neurobiological mechanisms underlying chronic pruritus have already led to the development of novel therapies, e. g., monoclonal antibodies against specific interleukins, which are important for pruritus transmission. A deeper understanding of the neurobiological mechanisms is necessary in order to develop specifically targeted therapeutic options and thus provide better care for affected patients.

Current treatment strategies in refractory chronic pruritus

Chronic pruritus is a highly prevalent, debilitating disease, which is often refractory to conventional therapies. A step-wise, guideline-driven approach should be adopted in the management of these patients. Emollients as well as topical corticosteroids if appropriate should be initiated whilst looking for the cause underlying the pruritus. If these measures fail, and the origin of the pruritus remains unknown, cannot be treated or does not respond to therapy, systemic therapies as for example gabapentinoids, antidepressants, mu-opioid-receptor antagonists or, in case of inflammatory conditions, immunosuppressive drugs should be recommended. Novel agents, especially systemic monoclonal antibodies, neurokinin-1 receptor antagonists and opioid receptor modulators, are promising in providing relief in refractory cases.

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.

[Chronic prurigo]

Chronic prurigo is a disease characterized by the presence of chronic pruritus and singular or multiple usually hyperkeratotic symmetrically distributed itchy papules, nodules, and/or plaques. This condition is difficult to treat and leads to a substantial impairment of the quality of life. It may originate from dermatological, systemic, neurological, psychiatric/psychosomatic, multifactorial or unknown conditions causing itch, which lead to prolonged scratching behavior and sensitization mechanisms and ultimately to the development of pruriginous lesions. Thorough diagnostic efforts, including a detailed clinical history and physical examination, as well as targeted complementary examinations should be initiated as soon as possible. The German guideline recommends topical steroids and phototherapy as first-choice options. Pimecrolimus and capsaicin (topical), as well as antihistamines, anticonvulsants, and immunosuppressive drugs (systemic) should be considered as valid alternatives.

[Acute emergencies in oncology]

The spectrum of dermato-oncological emergencies is multifaceted. They are particularly observed in cases with malignant melanoma due to the large number of patients and prolonged survival rates that are associated with new therapies for advanced disease. Dermato-oncological patients present to the hospital with symptoms like nausea and emesis, unexpected neurological deficits, various gastrointestinal problems, and even acute abdomen, acute breathlessness, or hemoptysis. Furthermore, emergencies can be caused by hematological problems like anemia and leukopenia. In addition to standardized care for medical emergencies, there are many other problems caused by metastases and/or therapeutic side effects that need interdisciplinary skills to optimize procedures and deliberate on surgical interventions, radiotherapy, and medical therapeutic choices with regard to the overall situation of the patient. The article deals with a spectrum of acute organ-specific emergencies, including recommendations for medical treatment and considerations for therapeutic decisions. Recommendations for supportive care in patients who are severely ill are summarized. In addition to stage-adapted pain therapy, supportive measures such as nutritional supplementation, the use of dronabinol in cases of loss of appetite, and antipruritic therapies are outlined. This article provides a succinct summary of the most frequently observed dermato-oncological emergencies with references to the respective detailed literature of associated medical societies and guidelines.