Vishnutheertha Kulkarni, David Liu, P. Aggarwal, V. Gamsarian, A. Fleischer
{"title":"Global epidemiology of itch from 1990 to 2017: gender, age, sanitation, and air pollution as risk factors","authors":"Vishnutheertha Kulkarni, David Liu, P. Aggarwal, V. Gamsarian, A. Fleischer","doi":"10.1097/itx.0000000000000060","DOIUrl":"https://doi.org/10.1097/itx.0000000000000060","url":null,"abstract":"Background: Itch is a symptom with significant physical, psychological, and financial burden worldwide. Symptom-specific and demographic risk factors have been published although community-level risk factors have not been thoroughly studied. Objectives: To describe the epidemiological risk factors of itch and to present a hypothesis that can account for these trends. Materials and methods: Itch incidence, prevalence, and years lost to disability (YLD) by age, sex, world region, socio-demographic index, percent of population using basic sanitation services, mortality due to air pollution, and gross domestic product (GDP) per capita were obtained from the University of Washington Institute for Health Metrics and Evaluation Global Burden of Disease (GBD), World Health Organization Global Health Observatory (WHO GHO), and Worldometer databases. Linear regression models were utilized to analyze the relationship of sanitation, air pollution, and GDP with itch incidence, prevalence and YLD. Results: Female sex and age were positively associated with higher incidence of itch. The percent of population using basic sanitation services was also positively correlated with itch incidence, prevalence, and YLD (P<0.001). Mortality rate due to air pollution was negatively associated with itch incidence, prevalence, and YLD (P<0.001). However, GDP per capita was not associated with the incidence (P=0.5), prevalence (P=0.8), and YLD (P=0.7) of itch. Conclusions: The “hygiene hypothesis” might explain global trends of itch as more industrialized countries have higher itch incidence rates. Thus, approaches which target molecular pathways involved in the “hygiene hypothesis” may lead to a decreased global itch burden.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"7 1","pages":"e60 - e60"},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46578706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Fujii, Shota Imahori, Misao Nakayama, T. Nabe, S. Ohya
{"title":"Tacrolimus suppresses itch-related response in diet-induced atopic dermatitis model mice by reducing chloroquine-sensitive sensory neurons","authors":"M. Fujii, Shota Imahori, Misao Nakayama, T. Nabe, S. Ohya","doi":"10.1097/itx.0000000000000062","DOIUrl":"https://doi.org/10.1097/itx.0000000000000062","url":null,"abstract":"Introduction: Itch (or pruritus) is a common symptom of atopic dermatitis (AD), which significantly decreases the patient’s quality of life. Tacrolimus ointment reduces pruritus in AD; however, the underlying mechanism is not fully understood. Methods: In the present study, we used a diet-induced AD mouse model to examine the antipruritic mechanism of tacrolimus. After induction of AD symptoms, the tacrolimus-containing ointment was applied once daily for 7 days. Responsiveness of isolated dorsal root ganglion (DRG) cells to various stimuli was examined by monitoring intracellular Ca2+ levels. Results: Repeated application of tacrolimus ointment attenuated spontaneous itch-related responses, even when skin barrier dysfunction, skin inflammation, and epidermal nerve sprouting were not ameliorated. Tacrolimus-treated mice also exhibited reduced scratching behavior induced by several pruritogens, such as histamine, SLIGRL-NH2, and chloroquine (CQ), although capsaicin-induced pain behavior was not affected. DRG cells from tacrolimus-treated mice showed significantly lower Ca2+ responses to CQ. Furthermore, a reduction in CQ-sensitive DRG neurons was observed after in vitro treatment with either tacrolimus or rapamycin. Discussion: CQ-sensitive (MrgprA3-expressing) DRG neurons are implicated as itch-specific sensory neurons. Therefore, topically applied tacrolimus may act directly on itch-signaling neurons, consequently suppressing various itch responses in AD mice.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"7 1","pages":"e62 - e62"},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44980893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jennifer M Becker, Sarah R. Vreijling, S. Van Damme, Elisa A. Kovacs, D. Veldhuijzen, A. Lavrijsen, D. V. Van Ryckeghem, G. Crombez, A. Evers, A. V. Van Laarhoven
{"title":"Attentional interference, but no attentional bias, by tonic itch and pain stimulation","authors":"Jennifer M Becker, Sarah R. Vreijling, S. Van Damme, Elisa A. Kovacs, D. Veldhuijzen, A. Lavrijsen, D. V. Van Ryckeghem, G. Crombez, A. Evers, A. V. Van Laarhoven","doi":"10.1097/itx.0000000000000063","DOIUrl":"https://doi.org/10.1097/itx.0000000000000063","url":null,"abstract":"Introduction: Attentional processes are involved in the experience of itch and pain. They interrupt task performance (ie, attentional interference) or bias allocation of attention toward the somatosensory stimulation, that is, attentional bias (AB). Research on AB toward pain is mostly focused on stimuli with short durations; hampering generalization to tonic pain sensations. Evidence for AB toward itch is lacking so far. This study investigated attentional interference by—and AB toward—experimentally induced tonic itch and pain. Methods: Fifty healthy volunteers performed a somatosensory attention task (SAT), that measured attentional interference and AB during tonic (35 s duration) pain, itch and vibrotactile stimuli. In addition, a dot-probe task measured AB toward visual representations of itch and pain, a Flanker task was used to assess attentional inhibition, and self-reported characteristics were measured. Results: Attentional interference during itch and pain stimuli compared with vibrotactile stimuli was found during the SAT. Exploration of shorter time segments within one tonic stimulus showed slowed responses for all three stimulus types during the first 5 seconds of stimulation. However, no prolonged interference in the following time segments was found. There was no AB toward somatosensory and visual stimuli. Furthermore, there was no association between any of the attentional measures and self-reported characteristics. Discussion: These findings suggest that the beginning of any somatosensory stimulus is interfering with cognitive performance, but the results for prolonged interference by itch and pain are equivocal. There was no indication for biased attention allocation. Whether this pattern is different in patients remains to be investigated in the future.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"7 1","pages":"e63 - e63"},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43650701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dorsal root ganglion neurostimulation: a target for treatment for intractable neuropathic itch?","authors":"A. Hawash, L. Kapural, G. Yosipovitch","doi":"10.1097/itx.0000000000000059","DOIUrl":"https://doi.org/10.1097/itx.0000000000000059","url":null,"abstract":"","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48473397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Prurigo pigmentosa: a case with rapid response to doxycycline and the likely pathogenetic role of neutrophils","authors":"Laura Hui, J. Lee, H. Tey","doi":"10.1097/itx.0000000000000051","DOIUrl":"https://doi.org/10.1097/itx.0000000000000051","url":null,"abstract":"","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43391476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Validation of the labeled magnitude scale for the assessment of itch intensity in patients with chronic pruritus","authors":"C. Zeidler, M. Röchter, S. Ständer, M. Pereira","doi":"10.1097/itx.0000000000000052","DOIUrl":"https://doi.org/10.1097/itx.0000000000000052","url":null,"abstract":"Introduction: The visual analogue scale (VAS), the numerical rating scale (NRS), and the verbal rating scale (VRS) are routinely used to assess pruritus intensity. However, these scales have limitations, especially the ceiling effect of linear scales (VAS, NRS) and the reduced sensitivity to change of the VRS. In the labeled magnitude scale (LMS) consisting of a vertical line with verbal anchors distributed quasi-logarithmically, the ceiling effect is reduced, allowing a higher discriminative assessment at the higher end of the scale. Methods: A total of 172 patients completed the LMS twice within 30–60 minutes to assess the reliability of the scale, as well as the NRS and VAS for analyses of convergent validity. Sensitivity to change of the LMS was investigated by analyzing changes in scores after a twice-daily application of an emollient containing menthoxypropanediol for 14 days. Results: Test-retest reliability was excellent for the LMS assessing average (Cronbach α: 0.955) and worst (Cronbach α: 0.945) pruritus intensity in the last 24 hours, while strong to very strong correlations were observed between the LMS and NRS assessing the worst (r=0.783) and average (r=0.808) pruritus intensity, respectively. Treatment with an emollient lead to a significant decrease in LMS scores (P<0.01). In patients with severe pruritus at baseline (VRS ≥3), we recorded a 30.2% improvement of average pruritus intensity using the LMS compared with a 25.0% improvement using the NRS and a 27.8% improvement of worst pruritus intensity using the LMS compared with an 11.1% improvement with the NRS. Most patients considered the LMS an appropriate instrument to assess pruritus intensity (89.6%) and would use it again (91.9%). Discussion: The LMS is an appropriate well-accepted instrument to assess CP. It is especially useful to detect variations in pruritus intensity in patients with severe CP.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"6 1","pages":"e52 - e52"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42606812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Paul, A. Yilmaz, B. Pieper, Zijuan Liu, S. Graham
{"title":"Prospective comparative study: metabolomics profiles of exudate and serum for patients with and without venous ulcer wound itch","authors":"J. Paul, A. Yilmaz, B. Pieper, Zijuan Liu, S. Graham","doi":"10.1097/itx.0000000000000046","DOIUrl":"https://doi.org/10.1097/itx.0000000000000046","url":null,"abstract":"Introduction: Itch is an unpleasant sensation that elicits the desire to scratch and can cause great distress, particularly in persons with venous ulcers. This pilot study explored the difference in metabolic profiles for wound exudate and serum in patients with or without venous ulcer wound itch. Methods: Patient information, wound assessment, and itch sensation ratings were recorded. Wound fluid and blood were collected for metabolomics assays. High-resolution mass spectrometry coupled with liquid chromatography and 1-dimensional proton nuclear magnetic resonance spectrometry were used to profile wound fluid and serum samples. Results: Patients (N=21) were included (ages: 32–91 y) with venous ulcers that itched (n=10) or did not itch (n=11). Metabolomic profiling discovered a previously unreported biochemical pathway for glycine, serine, and threonine metabolism in both serum and wound fluid significantly associated with itch. Using wound exudate, we developed diagnostic algorithms capable of discriminating between patients who itched and those who did not, with an area under the curve (95% confidence interval)=0.705 (0.461–0.948). Discussion: Our results demonstrate that the glycine-serine-threonine pathway is the most significantly altered metabolic pathway associated with venous ulcer itch. This pathway may serve as a biomarker for itch in patients with venous ulcers and help to identify itch before scratching further exasperates the ulcer. Studies with larger patient numbers are critically required to validate these findings. Our results may lead to novel therapeutic targets for the prophylactic treatment of itch.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"6 1","pages":"e46 - e46"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43643812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kent Sakai, K. M. Sanders, D. Pavlenko, Taisa Lozada, T. Akiyama
{"title":"Crisaborole prevents infiltration of neutrophils to suppress itch in a mouse model of atopic dermatitis","authors":"Kent Sakai, K. M. Sanders, D. Pavlenko, Taisa Lozada, T. Akiyama","doi":"10.1097/itx.0000000000000053","DOIUrl":"https://doi.org/10.1097/itx.0000000000000053","url":null,"abstract":"The phosphodiesterase-4 inhibitor crisaborole exerts an antipruritic effect and is effective for the treatment of mild-to-moderate atopic dermatitis. However, the mechanisms underlying the antipruritic effect of crisaborole are not completely understood. In this study, we tested whether crisaborole affects spontaneous itch-related behavior as well as neutrophil infiltration and epidermal nerve fiber density (ENFD) in the ovalbumin (OVA)-induced mouse model of atopic dermatitis. OVA treatment resulted in atopic-like skin lesions and spontaneous scratching, which was significantly inhibited by crisaborole treatment. OVA treatment significantly increased neutrophil infiltration and nonpeptidergic ENFD compared with vehicle-treated mice. Crisaborole significantly inhibited neutrophil infiltration without a significant effect on nonpeptidergic ENFD. In a cytokine array, crisaborole significantly decreased neutrophil chemokines, such as CXCL1, CXCL2, and CXCL5. Crisaborole may inhibit atopic dermatitis itch through inhibition of neutrophil infiltration and chemokine expression.","PeriodicalId":73523,"journal":{"name":"Itch (Philadelphia, Pa.)","volume":"6 1","pages":"e53 - e53"},"PeriodicalIF":0.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46032246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}