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Pruritus
Kinds of Pruritus Terms modified by Pruritus Selected AbstractsNeurophysiological and neurochemical basis of modern pruritus treatmentEXPERIMENTAL DERMATOLOGY, Issue 3 2008Sonja Ständer Abstract:, Chronic pruritus of any origin is a frequent discomfort in daily medical practice, and its therapy is challenging. Frequently, the underlying origin may not be identified and symptomatic therapy is necessary. Conventional treatment modalities such as antihistamines often lack efficacy, and hence new therapeutic strategies are necessary. The neuronal mechanisms underlying chronic pruritus have been partly identified during the past years and offer new therapeutic strategies. For example, mast cell degranulation, activation of neuroreceptors on sensory nerve fibres and neurogenic inflammation have been identified to be involved in induction and chronification of the symptom. Accordingly, controlling neuroreceptors such as cannabinoid receptors by agonists or antagonists showed high antipruritic efficacy. Pruritus is transmitted to the central nervous system by specialized nerve fibres and sensory receptors. It has been demonstrated that pruritus and pain have their own neuronal pathways with broad interactions. Accordingly, classical analgesics for neuropathic pain (gabapentin, antidepressants) also exhibit antipruritic efficacy upon clinical use. In summary, these recent developments show that highlighting the basis of pruritus offers modern neurophysiological and neurochemical therapeutic models and the possibility to treat patients with refractory itching of different origin. [source] Pathophysiology of pruritus in atopic dermatitis: an overviewEXPERIMENTAL DERMATOLOGY, Issue 1 2002Sonja Ständer Abstract: Pruritus is an essential feature of atopic dermatitis (AD) and the diagnosis of active AD cannot be made without the history of itching. Because of the high impact on life quality, most of the patients measure the severity of eczema by the intensity of pruritus rather than appearance of skin lesions. However, although pruritus is a cardinal symptom of AD, its mechanism and association with the cutaneous nervous system is not completely understood. Recently, a considerable progress has been achieved in clarifying the complex pathophysiology of pruritus in AD. As a cutaneous sensory perception, itch requires excitation of neuropeptide-containing free nerve endings of unmyelinated nociceptor fibers. It is well known that histamine and acetylcholine provoke itch by direct binding to ,itch receptors' and several mediators such as neuropeptides, proteases or cytokines indirectly via histamine release. Interestingly, some variations of these complex mechanisms could be demonstrated in patients with AD. This review highlights the recent knowledge of different mechanisms which may be involved in regulating pruritus in patients with AD potentially leading to new therapeutic applications for the treatment of itch in AD. [source] Uremic pruritus: A reviewHEMODIALYSIS INTERNATIONAL, Issue 2 2005Jocemir R. Lugon Abstract Pruritus is a major disorder among the skin derangements in advanced renal failure. Its prevalence seems to be diminishing perhaps because of improvements in dialysis treatment. Recent information suggests that interactions between dermal mast cells and distal ends of nonmyelinated C fibers may be important in the precipitation and regulation of the sensory stimuli. The knowledge as to the control of pruritus transmission to cortex areas is still incomplete but endogenous opioid and opioid receptors may have a role in this regard. A recent classification was proposed for pruritus based on the level of its origin. Uremic pruritus, however, seems to be too complex to fit perfectly in any of the suggested modalities. Inflammation and malnutrition are recognized risk factors for cardiovascular death in end-stage renal disease patients, which may be related to the genesis of pruritus. Consistent with this concept, lower serum levels of albumin and higher serum levels of ferritin were found in pruritic patients when compared to nonpruritic ones. Newer treatments for this difficult clinical problem are being developed and tested. [source] Aquagener Pruritus: Assoziierte Grunderkrankungen und klinische PrurituscharakteristikaJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 10 2010Tina Heitkemper First page of article [source] Pruritus and intermittent jaundice as clinical clues for Fasciola hepatica infestationLIVER INTERNATIONAL, Issue 6 2006HAYATI UMAC [source] Pathophysiology and therapy of pruritus in allergic and atopic diseasesALLERGY, Issue 7 2010J. Buddenkotte To cite this article: Buddenkotte J, Steinhoff M. Pathophysiology and therapy of pruritus in allergic and atopic diseases. Allergy 2010; 65: 805,821. Abstract Pruritus (itch) is a major characteristic and one of the most debiliating symptoms in allergic and atopic diseases and the diagnostic hallmark of atopic dermatitis. Pruritus is regularly defined as an unpleasant sensation provoking the desire to scratch. Although we achieved rather good knowledge about certain inducers of itch such as neuropeptides, amines, ,-opioids, cytokines and proteases, for example, less is known about the pathophysiological specifities among the different diseases, and the therapeutic consequences which may derive thereoff. This review dissects the role of mediators, receptors and itch inhibitors on peripheral nerve endings, dorsal root ganglia, the spinal cord and the CNS leading to the amplification or , vice versa , suppression of pruritus. As the treatment of pruritus in allergic and atopic skin disease is still not satisfactory, knowing these pathways and mechanisms may lead to novel therapeutic approaches against this frequently encountered skin symptom. [source] Clinicopathological study of Fox,Fordyce diseaseTHE JOURNAL OF DERMATOLOGY, Issue 9 2009Pei-Han KAO Abstract Fox,Fordyce disease (FFD) is a rare skin disease manifesting as multiple pruritic follicular papules involving the skin-bearing apocrine glands. Reports of FFD in Asian people are scant. In this retrospective study, we describe the clinicopathological findings of five cases of FFD affecting Taiwanese subjects. Clinically, all patients presented with numerous uniform, 2,3-mm, skin-colored to light brown, dome-shaped papules with smooth surface, which were distributed in the apocrine gland-containing areas. Pruritus varied from mild to severe. The histopathology is characterized by focal spongiosis in the upper infundibulum with perifollicular fibrosis and lymphohistiocytic infiltrate. FFD needs to be differentiated from lichen amyloidosis, Darier's disease, syringoma, lichen simplex chronicus and spongiotic dermatitis clinically or pathologically. The findings of focal spongiosis in upper infundibulum associated with a perifollicular lymphohistiocytic infiltrate can facilitate the diagnosis of FFD. [source] Pattern of skin and nail changes in chronic renal failure in Nepal: A hospital-based studyTHE JOURNAL OF DERMATOLOGY, Issue 3 2008Beni AMATYA ABSTRACT Chronic renal failure, regardless of its cause, often produces specific dermatological abnormalities, which can develop long before failure manifests clinically. Our aim was to study the clinical pattern of skin and nail changes in chronic renal failure and also study the associations of these changes with age, sex, etiology and duration of the chronic renal failure. A total of 104 diagnosed cases of chronic renal failure were included in the study over a period of 1 year. Equal numbers of age- and sex-matched individuals were taken as controls. The male : female ratio was 1.4:1. The mean duration of chronic renal failure was 19 ± 20 months. Among cases and controls, 72% and 16% had skin changes, respectively. Xerosis was the most common of the skin changes (28%), followed by hyperpigmentation (20%), pruritus (15%), infectious diseases (5%) and other skin changes (33%) in chronic renal failure patients. Abnormal nail changes were seen in 82% of the cases compared to only 8% of the controls. In the cases, white nail was most common followed by brown and half-and-half nail. Pruritus was significantly higher in the dialysis group whereas the nail changes were significantly higher in the non-dialysis group. The skin and nail changes were common in chronic renal failure and manifested in various forms. Thus, thorough inspection of the integument might reveal markers of occult renal disease. [source] Pruritus induced by interruption of paroxetine therapyBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2004C. Mazzatenta No abstract is available for this article. [source] The prevalence and clinical characteristics of pruritus among patients with extensive psoriasisBRITISH JOURNAL OF DERMATOLOGY, Issue 5 2000G. Yosipovitch Background,Many patients with psoriasis are known to suffer from itch. However, the data available regarding itch and its characteristics in psoriasis are sparse. Objectives,To examine the prevalence of pruritus and various related clinical characteristics in 101 patients with extensive psoriasis. Methods,A structured questionnaire was used. Results,Generalized pruritus was a feature of psoriasis in 84% of the patients. In 77% of these it appeared on a daily basis. It involved all areas of the body, had prolonged duration and appeared mainly in the evening and at night. The pruritus significantly affected quality of life. Important daily factors that were found to exacerbate the itch were ambient heat (81%), skin dryness (80%), sweating (65%) and stress (55%). Important factors that were found to ameliorate itch were sleep (57%) and cold showers (55%). The pruritus was found to be unresponsive to most available antipruritics, including phototherapy. Itch intensity as reflected by a visual analogue scale did not correlate with Psoriasis Area and Severity Index scores; however, a highly significant correlation was obtained between the affective descriptors and itch intensity in the worst itch states (r = 0·6, P < 0·001). Conclusions,Pruritus is a common feature of psoriasis and affects quality of life. [source] Opioid-induced pruritus: an updateCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 1 2010A. Reich Summary Pruritus is an unpleasant sensation leading to scratching. It can be a feature of numerous skin or systemic diseases, and may also be a side-effect of various drugs. Opioids are one of the best-known medicines evoking pruritus. The pathogenesis of opioid-induced pruritus is still not fully known, but two different mechanisms have been proposed: peripheral and central. Several treatment options have been tested for opioid-induced pruritus, but none has been completely satisfactory. Opioid antagonists seem to be the most potent antipruritic drugs, but they also decrease analgesia, which limits their usage. Many other treatments have been tried, but to date, the data are conflicting or only limited studies have been performed to confirm their efficacy. Further studies are still needed to better elucidate the mechanism of opioid-induced pruritus and to develop more effective treatment options. [source] Photoallergic contact dermatitis from topical diclofenac in Solaraze® gelCONTACT DERMATITIS, Issue 6 2006L. Kowalzick Solaraze® gel (Shire Deutschland GmbH & Co. KG, Cologne, Germany) containing 3% diclofenac has been licensed in 2001 as a topical treatment for actinic keratoses. It is commonly used in dermatological practice. Undesirable effects are believed to be rare but include pruritus, paresthesia and application-site reactions (dry skin, rash, erythema, contact dermatitis and vesicobullous eruptions). Recently, a few cases of contact dermatitis due to three different allergens including diclofenac have been reported (1,2). [source] Positive lymphocyte transformation test in a patient with allergic contact dermatitis of the scalp after short-term use of topical minoxidil solutionCONTACT DERMATITIS, Issue 1 2005Tobias Hagemann Topical 2,4-diamino-6-piperidinopyrimidine-3-oxide (minoxidil) solution has been widely used for the treatment of androgenetic alopecia for over 15 years now and the substance is currently approved for this indication in 2% and 5% formulation. Typical side effects of this topical treatment include irritative dermatitis going along with pruritus, erythema, scaling and dryness, which occur especially at the onset of the therapy. In some cases, allergic contact dermatitis or exacerbation of seborrhoic dermatitis has been reported. While most of the patients with allergic contact dermatitis described in the literature showed a positive sensitization to the vehicle substance propylene glycol evaluated by patch testing, reactions to the active ingredient minoxidil are rare. Here, we report a case of allergic sensitization to minoxidil, which we evaluated and differentiated from an irritative reaction by a combination of patch testing and lymphocyte transformation test. The differentiation of allergic and irritative adverse effects and the identification of the causative allergen are of major relevance for the proceeding and adjustment of the therapy. Patients with sensitizations against propylene glycol are candidates for preparations with alternative solvents but can proceed treatment with minoxidil. In contrast, patients with allergies to the active ingredient itself are no longer candidates for treatment with minoxidil and should undergo alternative therapeutic options. [source] FC03.2 Cumulative incidence of self reported skin disease in hydrotherapists working in swimming poolsCONTACT DERMATITIS, Issue 3 2004Aneta Lazarov Objective:, To assess the cumulative incidence and characteristics of self reported skin disease in hydrotherapists. Methods:, Hydrotherapists, who had completed a hydrotherapy training course answered a questionnaire in reference to newly appeared skin disease. Data were analyzed statistically. Results:, 190 subjects presently working as hydrotherapists were studied. Of them 75.8% were female and 24.2% were male. 80% of the hydrotherapists worked up to 10 000 cumulative hours defined by the formula: working hours per weeks × number of weeks per year × years of work in the pool. 85 of the subjects (45%) reported on the development of skin disease for the first time after starting work at the swimming pool. 21 (11.8%) had a preexisting skin disease. The most frequent symptoms included pruritus, burning, stinging, erythematous patches and xerotic skin on the extremities, trunk and folds. A statistically significant relationship between the cumulative working time and the incidence of dermatological pathology compatible with contact dermatitis was found. Conclusions:, The incidence of self reported skin diseases, developing for the first time or due to exacerbation of preexisting dermatological conditions, in hydrotherapists working in swimming pools is high. Statistically significant relationship between the cumulative hours of immersion in the pool and the incidence of the dermatological pathology was observed suggesting a dose response relationship between exposure and effect. [source] P58 Multisensitization to plants: clinical caseCONTACT DERMATITIS, Issue 3 2004António Luís Santos We observed a 65 years old male patient with pruritus, scaling erythema and liquenification areas on the face, neck, forearms and hands. For six years he had a story of episodic crisis of exsudative erythema associated with farm work. The skin biopsy showed irregular acantosis with slight hyperkeratosis and a mild multifocal lymphohistiocytic infiltrate, with many eosinophils. The patch tests with the Contact Dermatitis Portuguese Group of Study standard tray were positive for colophony, perfume mix and lactone mix. The patch tests with plant series were positive to atranorin, usnic acid, alantolactone, Parthenolide, lichen mix, Frulania dilatata, Achillea millefolium and Tanacetum extracts. Treatment was started with oral prednisone and hydroxyzine plus topical hydrocortisone and emollient cream with great improvement. The patient was advised about the avoidance of possible allergens sources. This kind of multisensitization to plants is an uncommon finding and poses diagnostic and therapeutic problems. This patient had a sustained recovery by avoiding farm work and by removal of in house plants. [source] THERAPEUTIC HOTLINE: Alefacept in the treatment of hyperkeratotic palmoplantar psoriasisDERMATOLOGIC THERAPY, Issue 5 2010Sagi Lior ABSTRACT Plaque-type palmoplantar psoriasis (PPP) is associated with marked morbidity and frequently resistant to conventional therapies. Patients with long-standing plaque-type PPP failing previous treatments were included and treated with a 12-week intramuscular alefacept. The biweekly evaluation included hyperkeratosis, itching, and pain grading. In all of the seven treated patients significant to complete improvement in hyperkeratosis, pruritus and pain were observed, along with dose reduction or complete discontinuation of additional systemic treatments and without any recorded side effects. Alefacept should be considered as a therapeutic option for plaque-type PPP. [source] Does food allergy cause atopic dermatitis?DERMATOLOGIC THERAPY, Issue 2 2006Food challenge testing to dissociate eczematous from immediate reactions ABSTRACT:, The objective is to evaluate and diagnose, in a controlled setting, suspected food allergy causation in patients hospitalized for management of severe, unremitting atopic dermatitis (AD). Nineteen children were hospitalized at Oregon Health and Science University with atopic dermatitis from 1986 to 2003 for food restriction, then challenge, following standard recommendations. Challenges were prioritized by categories of (a) critical foods (e.g., milk, wheat, egg, soy); (b) important foods; and (c) other suspected foods. Patients were closely observed for evidence of pruritus, eczematous responses, or IgE-mediated reactions. If results were inconsistent, double-blind, placebo-controlled food challenge was performed. A total of 17 children with atopic dermatitis were assessed. Two could not be fully evaluated, thus were excluded from data tabulations. Only one positive eczematous food response was observed of 58 challenges. Three children had well-documented histories of food-induced IgE-mediated anaphylactoid or urticaria reactions to seafood and/or nuts and were not challenged with those foods. Atopic dermatitis, even in the highest-risk patients, is rarely induced by foods. Undocumented assumptions of food causation detract from proper anti-inflammatory management and should be discouraged. Immediate IgE-mediated food reactions are common in atopic dermatitis patients; such reactions are rapid onset, typically detected outside the clinic, and must be distinguished from eczematous reactions. Diagnosis of food-induced eczema cannot be made without food challenge testing. Such tests can be practical and useful for dispelling unrealistic assumptions about food allergy causation of atopic dermatitis. [source] Itch and pruritus: what are they, and how should itches be classified?DERMATOLOGIC THERAPY, Issue 4 2005Jeffrey D. Bernhard ABSTRACT:, Itch and pruritus are two terms for the same thing. In this essay I will argue that casting about for a distinction between them creates only confusion. Once that matter is settled, it is still necessary to come up with a clinical classification for itches of different types. No system yet proposed, including the one that will be suggested here, is perfect. [source] Alternative therapy in pruritusDERMATOLOGIC THERAPY, Issue 2 2003Larry E. Millikan ABSTRACT: Because of its multitude of origins, the symptom complex of pruritus has a plethora of purported remedies and few therapeutic indications. Very few topical and systemic FDA approved medications have the indication of pruritus. Specific therapy still awaits a better definition of the exact physiologic events in chronic pruritus. Hence most medications actually focus on the central nervous system,the peripheral receptors,and the lack of specific physiologic targets has inhibited pharmacologic development. The resulting gap has opened the door to a variety of alternative therapies. [source] EOSINOPHILIC GASTROENTERITIS ASSOCIATED WITH GIANT FOLDSDIGESTIVE ENDOSCOPY, Issue 4 2010Kenji Ishido We describe a 54-year-old man who presented with right subcostal pain. Minocycline had been prescribed to treat pruritus, and the symptoms resolved. Subsequently, the patient consulted a local physician because of right subcostal pain. Giant folds were found in the greater curvature of the gastric body, and he was referred to the Department of Gastroenterology, Kitasato University East Hospital. Upper gastrointestinal endoscopy revealed markedly enlarged folds in the greater curvature of the stomach, with redness and edematous mucosa in the lesser curvature. Biopsy showed marked inflammatory cell infiltration (mainly eosinophils), but no atypical cells. Blood tests showed marked eosinophilia and elevated immunoglobulin E levels in the serum. The results of various allergic examinations were negative, but the clinical course suggested drug-induced eosinophilic gastroenteritis, and treatment was started. Minocycline was withdrawn without adequate resolution of symptoms. Because the leukocyte and eosinophil counts continued to increase, the patient was given suplatast, an anti-allergic agent. The symptoms and hematological values improved promptly. The patient recovered uneventfully, with no recurrence. [source] Treatment options for hydroxyurea-refractory disease complications in myeloproliferative neoplasms: JAK2 inhibitors, radiotherapy, splenectomy and transjugular intrahepatic portosystemic shuntEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2010Elena Mishchenko Abstract Clinical care of patients with polycythemia vera, essential thrombocythemia and myelofibrosis (MF) requires not only a broad understanding of general treatment principles but also familiarity with the management of hydroxyurea-refractory disease complications. The latter include progressive splenomegaly, symptomatic portal hypertension (e.g. ascites, variceal bleeding), pulmonary hypertension, bone pain, intractable pruritus, constitutional symptoms (e.g. fatigue, night sweats) and cachexia (i.e. loss of lean body mass, general ill health, poor appetite). Some of these symptoms are directly or indirectly related to extramedullary hematopoiesis (EMH) and others to proinflammatory cytokine excess. Results from recent clinical trials of JAK inhibitors suggest remarkable activity in MF-associated constitutional symptoms, cachexia, pruritus and hydroxyurea-refractory splenomegaly. Involved-field radiotherapy is best utilized in the setting of EMH-associated symptoms, including ascites, bone (extremity) pain and pulmonary hypertension. Splenectomy is indicated in the presence of drug-refractory splenomegaly and frequent red cell transfusion requirement. Transjugular intrahepatic portosystemic shunt is used to alleviate symptoms of portal hypertension. [source] Naltrexone: report of lack of hepatotoxicity in acute viral hepatitis, with a review of the literatureADDICTION BIOLOGY, Issue 1 2004Colin Brewer Many clinicians appear to be concerned about the potential hepatotoxicity of the opiate antagonist naltrexone (NTX) and this may be one reason why it is not used more widely in treating both heroin and alcohol abusers. Some much-quoted early studies noted abnormalities in liver function tests (LFTs) in very obese patients taking high doses, although there was no evidence of clinically significant liver dysfunction. These concerns may be reinforced by advice in the UK product information sheet to perform LFTs before and during treatment, by high infection rates with hepatitis C virus (HCV) among injecting heroin addicts and by the frequency of abnormal LFTs in alcohol abusers. We describe a heroin abuser in whom clinical and laboratory manifestations of acute hepatitis B and C appeared a few days after the insertion of a subcutaneous naltrexone implant. A decision was made not to remove the implant but the hepatitis resolved completely and uneventfully well within the normal time-scale. A review of the literature indicates that even when given at much higher doses than are needed for treating heroin or alcohol abusers, there is no evidence that NTX causes clinically significant liver disease or exacerbates, even at high doses, serious pre-existing liver disease. During the past decade, NTX has been shown to be safe and effective in the treatment of pruritus associated with severe jaundice caused by severe and sometimes life-threatening cirrhosis and other liver diseases. Its safety, even in these extreme conditions, is particularly reassuring. We suggest that it may be more appropriate and economical to advise patients to report promptly any suspected side effects than to perform regular LFTs, which may be misleading. [source] Atopic eczema or atopiform dermatitisEXPERIMENTAL DERMATOLOGY, Issue 4 2010Jan D. Bos Please cite this paper as: Atopic eczema or atopiform dermatitis. Experimental Dermatology 2010. Abstract:, Age period prevalence of atopic eczema (AE), a very common skin disease, has increased during the past decennia. This expansion seems to be ending in wealthy countries, while an increase is observed in developing nations, for which there is no firm explanation. Recent steps in understanding AE are the detection of skin barrier related filaggrin null mutations in approximately 25% of patients and the recognition of IL-31 as a molecule possibly involved in the itch (pruritus). Also interesting are the recognition of thymus and activation-regulated chemokine (TARC) and proliferating-inducing ligand (APRIL), as being associated with AE severity and activity. Immunocentric and corneocentric views on pathogenesis (the inside-outside paradigm) and the diagnostic entity atopiform dermatitis (AFD) are discussed here. We emphasize that diagnosing AE is not simple but challenging. We accentuate that a diagnosis of AE is only possible when there is allergen-specific IgE. Advice as to the need for elimination of allergens and adjustment of lifestyle are only proficient in patients having atopy and true AE, not in those having AFD. [source] Opioids and the skin , where do we stand?EXPERIMENTAL DERMATOLOGY, Issue 5 2009Paul L. Bigliardi Abstract:, The common ectodermal origin of the skin and nervous systems can be expected to predict likely interactions in the adult. Over the last couple of decades much progress has been made to elucidate the nature of these interactions, which provide multidirectional controls between the centrally located brain and the peripherally located skin and immune system. The opioid system is an excellent example of such an interaction and there is growing evidence that opioid receptors (OR) and their endogenous opioid agonists are functional in different skin structures, including peripheral nerve fibres, keratinocytes, melanocytes, hair follicles and immune cells. Greater knowledge of these skin-associated opioid interactions will be important for the treatment of chronic and acute pain and pruritus. Topical treatment of the skin with opioid ligands is particularly attractive as they are active with few side effects, especially if they cannot cross the blood,brain barrier. Moreover, cutaneous activation of the opioid system (e.g. by peripheral nerves, cutaneous and immune cells, especially in inflamed and damaged skin) can influence cell differentiation and apoptosis, and thus may be important for the repair of damaged skin. While many of the pieces of this intriguing puzzle remain to be found, we attempt in this review to weave a thread around available data to discuss how the peripheral opioid system may impact on different key players in skin physiology and pathology. [source] Neurophysiological and neurochemical basis of modern pruritus treatmentEXPERIMENTAL DERMATOLOGY, Issue 3 2008Sonja Ständer Abstract:, Chronic pruritus of any origin is a frequent discomfort in daily medical practice, and its therapy is challenging. Frequently, the underlying origin may not be identified and symptomatic therapy is necessary. Conventional treatment modalities such as antihistamines often lack efficacy, and hence new therapeutic strategies are necessary. The neuronal mechanisms underlying chronic pruritus have been partly identified during the past years and offer new therapeutic strategies. For example, mast cell degranulation, activation of neuroreceptors on sensory nerve fibres and neurogenic inflammation have been identified to be involved in induction and chronification of the symptom. Accordingly, controlling neuroreceptors such as cannabinoid receptors by agonists or antagonists showed high antipruritic efficacy. Pruritus is transmitted to the central nervous system by specialized nerve fibres and sensory receptors. It has been demonstrated that pruritus and pain have their own neuronal pathways with broad interactions. Accordingly, classical analgesics for neuropathic pain (gabapentin, antidepressants) also exhibit antipruritic efficacy upon clinical use. In summary, these recent developments show that highlighting the basis of pruritus offers modern neurophysiological and neurochemical therapeutic models and the possibility to treat patients with refractory itching of different origin. [source] How best to fight that nasty itch , from new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus to novel therapeutic approachesEXPERIMENTAL DERMATOLOGY, Issue 3 2005T. Biró While the enormous clinical and psychosocial importance of pruritus in many areas of medicine and the detrimental effects of chronic ,itch' on the quality of life of an affected individual are widely appreciated, the complexity of this sensation is still often grossly underestimated. The current Controversies feature highlights this complexity by portraying pruritus as a truly interdisciplinary problem at the crossroads of neurophysiology, neuroimmunology, neuropharmacology, protease research, internal medicine, and dermatology, which is combated most successfully if one keeps the multilayered nature of ,itch' in mind and adopts a holistic treatment approach , beyond the customary, frequently frustrane monotherapy with histamine receptor antagonists. In view of the often unsatisfactory, unidimensional, and altogether rather crude standard instruments for pruritus management that we still tend to use in clinical practice today, an interdisciplinary team of pruritus experts here critically examines recent progress in pruritus research that future itch management must take into consideration. Focusing on new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus, and discussing available neuropharmacological tools, specific research avenues are highlighted, whose pursuit promises to lead to novel, and hopefully more effective, forms of pruritus management. [source] A comparative study on the effects of naltrexone and loratadine on uremic pruritusEXPERIMENTAL DERMATOLOGY, Issue 9 2004E. Legroux-Crespel Two recent studies have provided opposite results on the efficacy of naltrexone on uremic pruritus. We have performed a third study. We compared efficacy and tolerance of naltrexone and loratadine on uremic pruritus. Among 296 hemodialysed patients, 65 suffered from uremic pruritus. 52 patients participated in the study. Patients were treated for 2 weeks with naltrexone (50 mg/day; 26 patients) or loratadine (10 mg/day; 26 patients), after a washout of 48 h. Pruritus intensity was scored by a visual analog scale (VAS). Adverse events were carefully searched. The two groups were statistically equivalent. There was no significant difference in the mean VAS scores after treatment, but naltrexone allowed a dramatic decrease of VAS sores (, > 3/10) in seven patients. Adverse events (mainly nausea and sleep disturbances) were observed in 10 of 26 patients. We could notice that 22% of hemodialysed patients suffered from uremic pruritus. Naltrexone was effective only in a subset of patients. Adverse events were very frequent. The differences of efficacy and tolerance between patients might be due to metabolism. Naltrexone might be considered as a second-line treatment. [source] Neuronal sensitization for itch in patients with chronic pruritusEXPERIMENTAL DERMATOLOGY, Issue 9 2004A. Ikoma Itch is one of the major symptoms of various skin diseases. Although specific neuronal pathways for itch were identified both peripherally and centrally, they still fail to explain itchy skin observed in patients with chronic pruritus. In this study, sensitivity to itchy and painful stimuli in patients with atopic dermatitis was investigated. Histamine-prick evoked enormous itch in their lesional skin, while less itch in their non-lesional skin than healthy subjects. Flare reaction was not significantly different between their non-lesional and lesional skin, rather smaller than healthy subjects. Mechanical (pin-pricks), electrical, heat and chemical (injection of pH3 solution) stimuli evoked intense itch in their lesional skin and partly also in their non-lesional skin, while only pain in healthy subjects. Itch was also, but not intensely, evoked in healthy subjects by injection of pH3 solution after sufficient histamine stimuli. These results confirm the presence of itchy skin with hyperkinesis (excessive itch by itchy stimuli) and allokinesis (itch by non-itchy stimuli) in patients with atopic dermatitis, which is so intense that painful stimuli cannot suppress but evoke itch, and suggest that neuronal sensitization is involved in their itch not only peripherally but also centrally. [source] Expression of vanilloid receptor subtype 1 in cutaneous sensory nerve fibers, mast cells, and epithelial cells of appendage structuresEXPERIMENTAL DERMATOLOGY, Issue 3 2004Sonja Ständer Abstract:, The vanilloid receptor subtype 1 (VR1)/(TRPV1), binding capsaicin, is a non-selective cation channel that recently has been shown in human keratinocytes in vitro and in vivo. However, a description of VR1 localization in other cutaneous compartments in particular cutaneous nerve fibers is still lacking. We therefore investigated VR1 immunoreactivity as well as mRNA and protein expression in a series (n = 26) of normal (n = 7), diseased (n = 13) [prurigo nodularis (PN) (n = 10), generalized pruritus (n = 1), and mastocytosis (n = 2)], and capsaicin-treated human skin (n = 6). VR1 immunoreactivity could be observed in cutaneous sensory nerve fibers, mast cells, epidermal keratinocytes, dermal blood vessels, the inner root sheet and the infundibulum of hair follicles, differentiated sebocytes, sweat gland ducts, and the secretory portion of eccrine sweat glands. Upon reverse transcriptase-polymerase chain reaction and Western blot analysis, VR1 was detected in mast cells and keratinocytes from human skin. In pruritic skin of PN, VR1 expression was highly increased in epidermal keratinocytes and nerve fibers, which was normalized after capsaicin application. During capsaicin therapy, a reduction of neuropeptides (substance P, calcitonin gene-related peptide) was observed. After cessation of capsaicin therapy, neuropeptides re-accumulated in skin nerves. In conclusion, VR1 is widely distributed in the skin, suggesting a major role for this receptor, e.g. in nociception and neurogenic inflammation. [source] Effect of the lactic acid bacterium Streptococcus thermophilus on stratum corneum ceramide levels and signs and symptoms of atopic dermatitis patientsEXPERIMENTAL DERMATOLOGY, Issue 5 2003Luisa Di Marzio Abstract:, A reduced amount of total ceramides could be responsible for functional abnormalities of the skin of atopic dermatitis (AD) patients. The ability of an experimental cream containing sonicated Streptococcus thermophilus to increase skin ceramide levels in healthy subjects has been previously reported. The aim of the present work was to investigate the effects of the topical administration of a S. thermophilus -containing cream on ceramide levels of stratum corneum from AD patients. A 2-week application of the cream, containing a sonicated preparation of the lactic acid bacterium S. thermophilus, in the forearm skin of 11 patients led to a significant and relevant increase of skin ceramide amounts, which could have resulted from the sphingomyelin hydrolysis through the bacterial sphingomyelinase. Moreover, in all patients the topical application of our experimental cream also resulted in the improvement of the signs and symptoms characteristic of AD skin (i.e. erythema, scaling, pruritus). [source] | |||||||||||||||||||||||||||||||