The effect of topically applied aspirin on localized circumscribed neurodermatitis

Lichen Simplex Chronicus Itch: An Update

Lichen simplex chronicus is a form of chronic localized pruritus with a secondary dermatitis, and one of the most common types of chronic itch conditions, estimated to affect more than 10% of the general population. However, despite its prevalence and burden, there has been limited research into the pathogenesis and aetiology of lichen simplex chronicus, which, historically, made it a challenging condition to treat. In recent years, our understanding of this condition, along with that of pruritus and the itch-scratch cycle, has increased greatly, enabling a substantial increase in treatment options. In addition, there are several new promising treatments currently in development and trials. This article discusses the definition, epidemiology, clinical characteristics, pathophysiology, and current therapeutic options for lichen simplex chronicus, in order to highlight recent advancements in this field.

Interventions for chronic pruritus of unknown origin

BACKGROUND

Pruritus is a sensation that leads to the desire to scratch; its origin is unknown in 8% to 15% of affected patients. The prevalence of chronic pruritus of unknown origin (CPUO) in individuals with generalised pruritus ranges from 3.6% to 44.5%, with highest prevalence among the elderly. When the origin of pruritus is known, its management may be straightforward if an effective treatment for the causal disease is available. Treatment of CPUO is particularly difficult due to its unknown pathophysiology.

OBJECTIVES

To assess the effects of interventions for CPUO in adults and children.

SEARCH METHODS

We searched the following up to July 2019: Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase, and trials registries. We checked the reference lists of included studies for additional references to relevant trials.

SELECTION CRITERIA

We sought to include randomised controlled trials and quasi-randomised controlled trials that assessed interventions for CPUO, as defined in category VI ('Other pruritus of undetermined origin, or chronic pruritus of unknown origin') of the International Forum for the Study of Itch (IFSI) classification, in children and adults. Eligible interventions were non-pharmacological or topical or systemic pharmacological interventions, and eligible comparators were another active treatment, placebo, sham procedures, or no treatment or equivalent (e.g. waiting list).

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were 'Patient- or parent-reported pruritus intensity' and 'Adverse events'. Our secondary outcomes were 'Health-related quality of life', 'Sleep disturbances', 'Depression', and 'Patient satisfaction'. We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We found there was an absence of evidence for the main interventions of interest: emollient creams, cooling lotions, topical corticosteroids, topical antidepressants, systemic antihistamines, systemic antidepressants, systemic anticonvulsants, and phototherapy. We included one study with 257 randomised (253 analysed) participants, aged 18 to 65 years; 60.6% were female. This study investigated the safety and efficacy of three different doses of oral serlopitant (5 mg, 1 mg, and 0.25 mg, once daily for six weeks) compared to placebo for severe chronic pruritus; 25 US centres participated (clinical research centres and universities). All outcomes were measured at the end of treatment (six weeks from baseline), except adverse events, which were monitored throughout. A pharmaceutical company funded this study. Fifty-five per cent of participants suffered from CPUO, and approximately 45% presented a dermatological diagnosis (atopic dermatitis/eczema 37.3%, psoriasis 6.7%, acne 3.6%, among other diagnoses). We unsuccessfully attempted to retrieve outcome data from study authors for the subgroup of participants with CPUO. Participants had pruritus for six weeks or longer. Total study duration was 10 weeks. Participants who received serlopitant 5 mg may have a greater rate of relief of patient-reported pruritus intensity as measured by the visual analogue scale (VAS; a reduction in VAS score indicates improvement) compared to placebo (126 participants, risk ratio (RR) 2.06, 95% confidence interval (CI) 1.27 to 3.35; low-certainty evidence). We are uncertain of the effects of serlopitant 5 mg compared to placebo on the following outcomes due to very low-certainty evidence: adverse events (127 participants; RR 1.48, 95% CI 0.87 to 2.50); health-related quality of life (as measured by the Dermatology Life Quality Index (DLQI); a higher score indicates greater impairment; 127 participants; mean difference (MD) -4.20, 95% CI -11.68 to 3.28); and sleep disturbances (people with insomnia measured by the Pittsburgh Sleep Symptom Questionnaire-Insomnia (PSSQ-I), a dichotomous measure; 128 participants; RR 0.49, 95% CI 0.24 to 1.01). Participants who received serlopitant 1 mg may have a greater rate of relief of patient-reported pruritus intensity as measured by VAS compared to placebo; however, the 95% CI indicates that there may also be little to no difference between groups (126 participants; RR 1.50, 95% CI 0.89 to 2.54; low-certainty evidence). We are uncertain of the effects of serlopitant 1 mg compared to placebo on the following outcomes due to very low-certainty evidence: adverse events (128 participants; RR 1.45, 95% CI 0.86 to 2.47); health-related quality of life (DLQI; 128 participants; MD -6.90, 95% CI -14.38 to 0.58); and sleep disturbances (PSSQ-I; 128 participants; RR 0.38, 95% CI 0.17 to 0.84). Participants who received serlopitant 0.25 mg may have a greater rate of relief of patient-reported pruritus intensity as measured by VAS compared to placebo; however, the 95% CI indicates that there may also be little to no difference between groups (127 participants; RR 1.66, 95% CI 1.00 to 2.77; low-certainty evidence). We are uncertain of the effects of serlopitant 0.25 mg compared to placebo on the following outcomes due to very low-certainty evidence: adverse events (127 participants; RR 1.29, 95% CI 0.75 to 2.24); health-related quality of life (DLQI; 127 participants; MD -5.70, 95% CI -13.18 to 1.78); and sleep disturbances (PSSQ-I; 127 participants; RR 0.60, 95% CI 0.31 to 1.17). The most commonly reported adverse events were somnolence, diarrhoea, headache, and nasopharyngitis, among others. Our included study did not measure depression or patient satisfaction. We downgraded the certainty of evidence for all outcomes due to indirectness (only 55% of study participants had CPUO) and imprecision. We downgraded outcomes other than patient-reported pruritus intensity a further level due to concerns regarding risk of bias in selection of the reported result and some concerns with risk of bias due to missing outcome data (sleep disturbances only). We deemed risk of bias to be generally low.

AUTHORS' CONCLUSIONS

We found lack of evidence to address our review question: for most of our interventions of interest, we found no eligible studies. The neurokinin 1 receptor (NK1R) antagonist serlopitant was the only intervention that we could assess. One study provided low-certainty evidence suggesting that serlopitant may reduce pruritus intensity when compared with placebo. We are uncertain of the effects of serlopitant on other outcomes, as certainty of the evidence is very low. More studies with larger sample sizes, focused on patients with CPUO, are needed. Healthcare professionals, patients, and other stakeholders may have to rely on indirect evidence related to other forms of chronic pruritus when deciding between the main interventions currently used for this condition.

The color of skin: red diseases of the skin, nails, and mucosa

Red color is pervasive in local and systemic skin conditions. It is a color that often reflects variations of dermal blood flow and extends beyond the rubor and calor of inflammation. The pathophysiology of red skin involves remote and local chemical mediators that dilate arteriolar smooth muscle and increase blood flow to superficial vessels and capillary beds. Incident light hits hemoglobin, which preferentially absorbs light of shorter wavelengths, such as blue, and reflects warmer colors. Due to its pervasiveness and consistency, red color is a useful descriptive factor in helping narrow a differential diagnosis. Red skin disorders include a variety of conditions involving endocrine mediators, cardiovascular responses, and the disruption of the skin barrier. An understanding of the blood's role in these disorders equips clinicians to generate differential diagnoses through the lens of pathophysiology. Dermatologists can improve management by considering red skin as part of systemic disease rather than as an isolated incident.

Causes, pathophysiology, and treatment of pruritus in the mature patient

Chronic itch is a common and debilitating health condition in the elderly. There are several common causes of itch in the mature population, such as skin xerosis, immunosenescence, and neuropathic changes. In addition, skin diseases, such as seborrheic dermatitis and stasis dermatitis, systemic conditions (end-stage renal disease and diabetes), or psychogenic derailments, such as depression, anxiety, and dementia, can all serve as triggers of pruritus. Polypharmacy, a common occurrence among the elderly population, may also serve as a cause of itch that may or may not be accompanied by dermatitis. Such medications as μ opioids and calcium channel blockers have been found to have a connection with pruritus in the advanced aging population. Determining the exact trigger for pruritus in the elderly may be especially challenging, because itch can be idiopathic in many cases. The role of treatments should not only take into account elimination of various underlying cutaneous, systemic, or psychogenic conditions associated with itch but also focus on the skin changes that are characteristic of the aging process. Development of such treatment options can be guided by elucidation of the mechanisms underlying the pathophysiology of itch in the geriatric population.

Efficacy of Topical Therapy with Newly Developed Terbinafine and Econazole Formulations in the Treatment of Dermatophytosis in Cats

In the field of veterinary dermatology dermatophytosis is one of the most frequently occurring infectious diseases, therefore its treatment should be effective, convenient, safe and inexpensive. The aim of this study was to evaluate the efficacy of newly developed topical formulations in the treatment of cats with dermatophytosis. Evaluation of clinical efficacy and safety of terbinafine and econazole formulations administered topically twice a day was performed in 40 cats. Cats, suffering from the most widely spread Microsporum canis-induced dermatophytosis and treated with terbinafine hydrochloride 1% cream, recovered within 20.3±0.88 days; whereas when treated with econazole nitrate 1% cream, they recovered within 28.4±1.14 days. A positive therapeutic effect was yielded by combined treatment with local application of creams and whole coat spray with enilconazole 0.2% emulsion "Imaverol". Most cats treated with econazole cream revealed redness and irritation of the skin at the site of application. This study demonstrates that terbinafine tended to have superior clinical efficacy (p<0.001) in the treatment of dermatophytosis in cats compared to the azole tested.

Chronic pruritus in the elderly: pathophysiology, diagnosis and management

Chronic itch in the elderly is a common problem, with a significant impact on quality of life and sleep in elderly patients. Chronic itch may be attributable to several causes, including dry skin, immunosenescence and neural degeneration. Itch may also be caused by skin diseases, such as seborrhoeic dermatitis and stasis dermatitis; systemic conditions, such as end-stage renal disease and diabetes; and psychogenic conditions, such as depression and anxiety. The use of polypharmacy may also cause itch, with or without a rash. Specifically, thiazides and calcium channel blockers have been known to cause itch in elderly patients. Management should be tailored according to the underlying dermatological or systemic aetiology of itch. Topical treatment is the mainstay of therapy, providing special emphasis on skin hydration and barrier repair. In addition, topical and oral medications that target the nervous system and reduce neuronal hypersensitization, such as gabapentin and selective antidepressants, have a role in treating patients with severe chronic itch. Furthermore, management must account for changes in metabolism and pharmacokinetics of drugs in the aging population in order to prevent the occurrence of adverse effects.

Current topical and systemic therapies for itch

Itch is a common distressing symptom which may be caused by multifactorial aetiologies including inflammatory skin diseases, systemic diseases, neuropathic conditions and psychogenic disorders. Itch is a term used synonymously with pruritus and is defined as acute if it lasts less than 6 weeks or chronic if it persists for more than 6 weeks. It can have the same impact on the quality of life as chronic pain and shares many of the same pathophysiological pathways. Depending on the aetiology of the itch, different pathogenic mechanisms have been postulated with a number of mediators identified. These include histamine, leukotrienes, proteases, neuropeptides, cytokines and opioids, which may activate peripheral itch-mediating C-fibres via receptors on the nerve terminals and central neuronal pathways. Therefore, there is no single universally effective anti-itch treatment available. First-line treatments for itch include topical therapies, such as emollients, mild cleansers (low pH), topical anaesthetics, steroids, calcineurin inhibitors and coolants (menthol). Treatment with systemic therapies can vary according to the aetiology of the chronic itch. Non-sedating antihistamines are helpful in conditions such as urticaria where the itch is primarily histamine mediated. Although the itch of eczema is not mediated by histamine, sedating antihistamines at night are helpful to break the itch-scratch cycle. Chronic itch may also be treated with other systemic therapies, such as anticonvulsants, antidepressants as well as mu-opioid antagonists, kappa-opioid agonists and phototherapy, depending on the cause of the itch. This article summarises the topical and systemic therapies available with our current understanding of the pathophysiology of itch.

[Pseudo-condylomatous neurodermatitis of the anal margin]

Cerebral venous thrombosis (CVT) is a rare origin of stroke, the clinical presentation and etiologies vary. The prognosis is shown to be better compared to arterial thrombosis. Magnetic Resonance Imaging (MRI) and MR Venograpgy (MRV) are currently important tools for the diagnostic. We studied 30 cases of CVT diagnosed in the department of neurology of the University Hospital of Fez (Morocco). Patients diagnosed with CVT signs between January 2003 and October 2007 were included in the study. Cerebral CT-scan was performed in 27 cases (90%) while the MRI examination was done in 18 patients (67%); and most patients (90%) received anticoagulant therapy. The mean age of our patients was of 29 years (age range between 18 days and 65 years). A female predominance was observed (70%). The clinical presentation of patients was dominated by: headache in 24 cases (80%), motor and sensory disability in 15 cases (50%), seizures in 10 cases (33%) , consciousness disorder in 10 cases (33%). CVT was associated to post-partum in 10 cases (33%), infectious origin in 8 cases (26%), Behcet disease in 2 cases (7%), pulmonary carcinoma in 1 case, thrombocytemia in 1 case and idiopathic in 7 cases (23%). The evolution was good in 20 cases (67%), minor squelaes were observed in 6 patients (20%), while major squelaes was observed in 2 cases. Two cases of death were registered. The CVT is a pathology of good prognosis once the diagnosis is promptly established and early heparin treatment initiated.

Therapy of pruritus

IMPORTANCE OF THE FIELD

Pruritus is the predominant symptom of skin disease. Owing to the poorly understood pathophysiology, the development of effective treatment modalities for pruritus has proven to be particularly difficult. At present, there is no universally accepted therapy for itch. The purpose of this review is to provide an update on the treatment of pruritus.

AREAS COVERED IN THIS REVIEW

An overview of current, emerging and possible future therapies for pruritus is provided.

WHAT THE READER WILL GAIN

Insights into possible treatment regimes for pruritus in different clinical scenarios.

TAKE HOME MESSAGE

The therapy of pruritus is challenging and at present takes on an individualistic approach. Recent advancements in the mechanisms that underlie this distressing symptom have identified new targets for future therapy.

Topical tacrolimus for the treatment of lichen simplex chronicus

Owing to severe itching and scratching, the natural course of lichen simplex chronicus (LSC) is clinically characterized by typical lichenoid lesions. Topical corticosteroids are often used to treat LSC but after withdrawal a relapse will sometimes occur. Therefore, LSC can be difficult to treat over time. We report a 13-year-old boy suffering from LSC on two symmetrical circumscribed areas on the temple, whose lesions healed completely with tacrolimus 0.1% ointment within approximately 9 months. During active treatment no adverse drug reaction was observed. The patient is completely free of symptoms 3 years after cessation of treatment. We conclude that topical tacrolimus can be used as an effective, long-lasting therapeutic modality in treating LSC, especially in sensitive skin areas such as the face.

Possible involvement of 5-lipoxygenase metabolite in itch-associated response of mosquito allergy in mice

This study investigated endogenous mediators involved in mosquito allergy-associated itching in mice. An intradermal injection of an extract of mosquito salivary gland elicited marked scratching in sensitized mice. The 5-lipoxygenase inhibitor zileuton (100 mg/kg), the 5-lipoxygenase activating peptide inhibitor MK-886 (10 mg/kg), and the glucocorticoid betamethasone 17-valerate (3 mg/kg) inhibited the scratching. The scratching was not affected by the cyclooxygenase inhibitors indomethacin and ketoprofen, the TP prostanoid receptor antagonist SQ-29548, the leukotriene B(4) antagonist ONO-4057, the cysteinyl leukotriene antagonist pranlucast, the leukotriene D(4) antagonist MK-571, the platelet-activating factor antagonist CV-3988, the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester, the H(2) histamine-receptor antagonist cimetidine, the H(1) histamine-receptor antagonist terfenadine plus cimetidine, and cypoheptadine that blocks the 5-HT(1/2) serotonin receptors. Zileuton (100 mg/kg) inhibited the increased activity of the cutaneous nerve branch induced by an intradermal injection of the extract, suggesting the peripheral action. Zileuton and MK-886 (10 and 100 microM) did not affect high K(+)-induced increase in intracellular Ca(2+) concentration in cultured dorsal root ganglion neurons. The results suggest that 5-lipoxygenase metabolite(s) other than leukotriene B(4) and cysteinyl leukotrienes are involved in mosquito allergy-associated itching.

The pruritus receptor unit: a target for novel therapies

Although the role of prostanoids in itch was actively studied a decade ago, interest in this area has waned in recent years. Andoh et al. (2007, this issue) demonstrate that the prostanoid thromboxane A2 elicits scratching through its TP receptor. Identification of new itch mediators and their respective receptors within the skin will undoubtedly be the focus of future drug development for this distressing symptom.

Thromboxane A2 induces itch-associated responses through TP receptors in the skin in mice

Thromboxane A2 (TXA2), a metabolite of arachidonic acid produced by cyclooxygenase and thromboxane synthase, is thought to participate in chronic dermatitis. This study investigated the involvement of TXA2 in cutaneous itch. An intradermal injection of U-46619, a stable analogue of TXA2, elicited scratching, an itch-associated response, in mice. Dose-response curve was bell shaped with a maximum effect at 10 nmol per site. The action of U-46619 was inhibited by a coinjection of the TP antagonist ONO-3708 and was abolished by TP receptor deficiency. TP receptor was mainly expressed in nerve fiber in the skin and keratinocytes. Thromboxane synthase was also expressed in keratinocytes. U-46619 increased intracellular Ca2+ ion concentration in primary cultures of dorsal root ganglion neurons and keratinocytes. The results suggest that TXA2 synthesized by keratinocytes acts as an itch mediator. It may elicit itch through the activation of TP receptors on primary afferents and keratinocytes; keratinocytes may produce itch mediators including TXA2. Thus, thromboxane synthase inhibitor and TP receptor antagonists will be candidates for antipruritic medicines.

COX-1 inhibition enhances scratching behaviour in NC/Nga mice with atopic dermatitis

NC/Nga (NC) mice, spontaneously develop an eczematous atopic dermatitis (AD)-like skin lesion when kept under conventional condition (Conv), but not under specific pathogen-free (SPF) conditions, have been thought to be an animal model of AD. We have previously shown that PGD(2) and arachidonic acid inhibited the scratching behaviour of NC mice, while indomethacin enhanced it. This study was designed to assess the role of cyclooxygenase (COX)-1 and COX-2 in the itch-related scratching behaviour of NC mice. We examined the expression of COX in the skin using real-time PCR and Western blotting and the effects of SC-560 (a COX-1 selective inhibitor) or NS-398 (a COX-2 selective inhibitor) on scratching behaviour in relation to skin prostaglandin (PG) levels in NC mice. COX-1 mRNA expression was unchanged and protein expression decreased in Conv NC mice compared with that of SPF mice. By contrast, COX-2 mRNA and protein expression increased in Conv NC mice. SC-560 increased scratching behaviour and significantly reduced skin PGD(2), PGE(2) and PGF(2alpha) levels, but NS-398 did not have effects on scratching and skin PG level. Moreover, the topical application of PGD(2), which might be the endogenous inhibitor of itching, suppressed the SC-560-induced enhancement of scratching behaviour by NC mice. These results suggest COX-1-coupled skin PGD(2) biosynthesis plays a physiological role in inhibiting regulation of pruritus in NC mice with AD.

Sleep Disturbance in Patients with Lichen Simplex Chronicus and Its Relationship to Nocturnal Scratching: A Case Control Study

BACKGROUND

Lichen simplex chronicus (LSC) is a common pruritic disorder resulting from repeated rubbing and scratching. Nighttime pruritus is a common feature in LSC and may disrupt the sleep pattern. The aim of this study is to determine whether there are sleep abnormalities in patients with LSC.

PATIENTS AND METHODS

Fifteen patients with LSC and 15 age-, sex- and body mass index-matched control subjects were enrolled in the study. No participant had any other medical or psychiatric illness. All subjects were evaluated by overnight polysomnography, scratch electrodes, Epworth sleepiness scale and a general questionnaire for demographic data and sleep problems.

RESULTS

There were no significant differences in the groups for total sleep time, sleep efficiency, sleep latency, rapid eye movement (REM) latency, percentage of stage 1 non-REM sleep and REM sleep. The percentage of stage 2 non-REM sleep was higher (P < 0.05) and the percentage of slow wave sleep (stages 3 and 4) was lower in the study group (P < 0.05) than in the controls. The patient group had a mean of 15.9 +/- 7.5 arousal index and 22.8 +/- 14.1 awakenings compared with 9.5 +/- 3.1 and 10.4 +/- 3.9, respectively, in the controls (P < 0.05, P < 0.01, respectively). Arousals of patients were mainly observed in non-REM sleep. The number of scratching bouts ranged from 6 to 20 per night. Scratching episodes were observed frequently during stage 2 non-REM sleep.

CONCLUSION

Polysomnographic findings of patients with LSC demonstrated that sleep structure is disturbed by arousals and awakenings related to scratching bouts during sleep.

[Pruritus in pregnancy. A frequent diagnostic and therapeutic challenge]

Pruritus is the leading dermatological symptom during pregnancy. Besides preexisting or acquired dermatoses, there are a number of pregnancy-specific dermatological diseases such as PEP (polymorphic eruption of pregnancy, previously named PUPPP), pemphigoid (herpes) gestationis, and pruritus gravidarum that are accompanied by severe itching and scratching. Because of potential effects on the fetus, the treatment of pruritus in pregnancy requires prudent consideration. The use of topical and systemic treatments depends on the underlying aetiology of pruritus and the stage and status of the skin. In general, emollients, topical anti-pruritics and topical corticosteroids appear to be the safest options for localised forms of pruritus in pregnancy whereas systemic treatments and/or UV phototherapy are adequate for generalized pruritus. Systemic corticosteroids and a restricted number of antihistamines may be administered in severe cases. This paper highlights the major aetiologies of pruritus during pregnancy and points out the cornerstones of antipruritic therapy in recognition of our own clinical experiences and the current literature.

Over-the-counter topical antipruritic agents are commonly recommended by office-based physicians: an analysis of US practice patterns

BACKGROUND

Pruritus is one of the most common complaints among patients who visit physicians. Over-the-counter topical antipruritic medications are widely recommended by physicians and are self-administered by patients for the treatment of pruritus. However, there are few scientific controlled studies evaluating the effect of these drugs on pruritus.

OBJECTIVES

To assess the role of physician-recommended over-the-counter medications for the treatment of pruritus.

METHODS

Records were analyzed for office-based physician visits in which over-the-counter antipruritic topical medications were recommended in the National Ambulatory Medical Care Survey between the years 1995 and 2000.

RESULTS

The largest proportion of over-the-counter antipruritic agent recommendations were during visits to dermatologists, accounting for 41% of all such recommendations. Other physicians that recommended such agents included family physicians and pediatricians, accounting respectively for 26% and 21% of the recommendations. The most commonly recommended over-the-counter medications included hydrocortisone preparations (72%) and diphenhydramine (15%). Over-the-counter medications were more frequently recommended in the pediatric age group.

CONCLUSION

This study demonstrates that over-the-counter medications are frequently recommended for the treatment of pruritus.

Itch associated with skin disease: advances in pathophysiology and emerging therapies

Itch, also known as pruritus, is the major symptom in skin diseases with a variety of etiologies and pathophysiologies. Significant progress has been achieved in understanding the pathophysiology of itch in the last 5 years. Neurophysiological experiments in humans and animals have revealed that itch is carried by specific C nerve fibers. Recent studies have demonstrated that peripheral mediators other than histamine are involved in induction of itch. Mast cell tryptase seems to be an important mediator in itch by its activation of proteinase activated receptor 2 in the sensory nerves. Opioids have central and peripheral itch producing activity. Neuropeptides, such as substance P, induce itch by their effect on mast cells. Based upon our improved understanding of the neurophysiology of itch a clinical classification of itch has been proposed. The classification highlights differences between peripheral pruritoceptive itch, neuropathic itch (itch related to damage to afferent nerve fibers) and neurogenic itch (itch originating in the central nervous system without any evidence of nerve damage). Emerging therapies based on these findings include topical vanilloid receptor antagonists, topical antihistamines, and topical arachidonic acid inhibitors, as well as inhibitors of non-histamine inflammatory mediators, immunomodulators and strontium salts. Systemic therapies include thalidomide, opioid antagonists, phototherapy with narrow band UVB and experimental treatments with cutaneous field stimulation and vagal nerve stimulation. With the new information it seems we will be able to better help our dermatologic patients who have itch, however we are not closer to identifying a single agent specifically targetable to this symptom.

Skin diseases of the lower extremities in the elderly

Routine care of the legs and feet in the elderly is important in helping to prevent infections, malignancies, and further deterioration. The lower extremities are of particular interest because of the increasing amount of diseases and disorders involving the legs and feet. Foot disorders in the elderly are associated with poor choices in footwear, structural changes, brought on by aging, and inadequate knowledge about prevention and treatment. Conservative treatments along with gait modification provide positive long-term results, although sometimes surgery is necessary for severe foot disorders. Onychomycosis and other nail disorders commonly infect the elderly despite the wide variety of treatment options. The increase in malignancy formation in the elderly is caused by the increase in the elderly population and inadequate treatment of leg ulcers and other chronic lesions. Aging is associated with many dermatologic changes; many of the disorders and diseases of the lower extremities can be managed if detected and treated early. Proper awareness of the signs, symptoms, and care is important.

Itch

Itch is a common skin sensation, with substantial effects on behaviour. Neurophysiological research has permitted accurate definition of neural pathways of itch, and has confirmed the distinctiveness of itch pathways in comparison with pain. A clinical classification of itch, based on such improved understanding, describes the difference between peripheral (pruritoceptive) and central (neurogenic or neuropathic) itch. New specific and sensitive investigational methods in people and animals enable us to better understand this bothersome symptom, and have important clinical implications. We describe the clinical classification of itch, new findings on neuropathophysiology of itch, methods for assessment, and improved treatments.

Pruritus - Pathophysiologie, Klinik und Therapie - Eine Ubersicht. Pruritus - pathophysiology, clinical features and therapy - an overview

Pruritus is an unpleasant sensory perception of the skin associated with the desire to scratch. As a physiological nociception, pruritus leads to the removal of harmful agents such as parasites and plants from the skin surface. More often, pruritus occurs as a severe and therapy-refractory symptom of various underlying dermatological and systemic diseases. Comparable to chronic pain, chronic pruritus worsens the general condition and may lead to physical and psychological exhaustion. Until the 1990s, pruritus had been regarded as an incomplete pain sensation. Only recently, itch was defined as a separate, pain-independent sensation with its own mediators, spinal neurons and cortical areas. These observations led to the development of new therapeutic modalities. This paper gives an overview of itch pathophysiology, clinical types and therapies.