Scalp Pruritus: Review of the Pathogenesis, Diagnosis, and Management

Artificial intelligence-based prescription of personalized scalp cosmetics improved the scalp condition: efficacy results from 100 participants

Background: Scalp-related symptoms such as dandruff and itching are common with diverse underlying etiologies. We previously proposed a novel classification and scoring system for scalp conditions, called the scalp photographic index (SPI); it grades five scalp features using trichoscopic images with good reliability. However, it requires trained evaluators.Aim: To develop artificial intelligence (AI) algorithms for assessment of scalp conditions and to assess the feasibility of AI-based recommendations on personalized scalp cosmetics.Methods: Using EfficientNet, convolutional neural network (CNN) models (SPI-AI) ofeach scalp feature were established. 101,027 magnified scalp images graded according to the SPI scoring were used for training, validation, and testing the model Adults with scalp discomfort were prescribed shampoos and scalp serums personalized according to their SPI-AI-defined scalp types. Using the SPI, the scalp conditions were evaluated at baseline and at weeks 4, 8, and 12 of treatment.Results: The accuracies of the SPI-AI for dryness, oiliness, erythema, folliculitis, and dandruff were 91.3%, 90.5%, 89.6%, 87.3%, and 95.2%, respectively. Overall, 100 individuals completed the 4-week study; 43 of these participated in an extension study until week 12. The total SPI score decreased from 32.70 ± 7.40 at baseline to 15.97 ± 4.68 at week 4 (p < 0.001). The efficacy was maintained throughout 12 weeks.Conclusions: SPI-AI accurately assessed the scalp condition. AI-based prescription of tailored scalp cosmetics could significantly improve scalp health.

Unmet needs in treating itch: reaching beyond eczema

PURPOSE

Pruritus is an unpleasant sensation that creates the urge to scratch. In many chronic conditions, relentless pruritus and scratching perpetuates a vicious itch-scratch cycle. Uncontrolled itch can detrimentally affect quality of life and may lead to sleep disturbance, impaired concentration, financial burden, and psychological suffering. Recent strides have been made to develop guidelines and investigate new therapies to treat some of the most common severely pruritic conditions, however, a large group of diseases remains underrecognized and undertreated. The purpose of this article is to provide a comprehensive review of the challenges hindering the treatment of pruritus.

METHODS

An online search was performed using PubMed, Web of Science, Google Scholar, and ClinicalTrials.gov from 1994 to 2024. Included studies were summarized and assessed for quality and relevance in treating pruritus.

RESULTS

Several barriers to treating pruritus emerged, including variable presentation, objective measurement of itch, and identifying therapeutic targets. Itch associated with autoimmune conditions, connective tissue diseases, genodermatoses, cutaneous T-cell lymphoma, and pruritus of unknown origin were among the etiologies with the greatest unmet needs.

CONCLUSION

Treating pruritus poses many challenges and there are many itchy conditions that have no yet been addressed. There is an urgent need for large-scale controlled studies to investigate potential targets for these conditions and novel therapies.

Lichen Sclerosus of the Labial Mucosa: A Case Report and Literature Review

Lichen sclerosus (LS) is an uncommon, chronic, inflammatory mucocutaneous disorder found predominantly in females with unknown etiology. It presents as a white sclerotic plaque commonly located on the anogenital area. Extragenital LS is less prevalent, and LS affecting the oral mucosa is extremely rare, with only 39 biopsy-confirmed cases reported in the literature. Due to its several mimicking conditions, histological examination is usually required for a definitive diagnosis, particularly in patients with oral LS. Current evidence-based treatment recommendations for oral LS are unavailable; however, most cases tend to improve after treatment with topical or intralesional corticosteroids. We report a case of a 58-year-old female referred from the otolaryngology department for evaluating an asymptomatic whitish sclerotic plaque on the lower lip mucosa that had existed for 1 year. Following a punch biopsy, the patient was diagnosed with LS of labial mucosa. The condition improved after 2 months of treatment with topical and intralesional corticosteroids. The present case report raises awareness in recognizing oral LS and contributes to knowledge of this rare disorder.

A rare case report: chronic generalized idiopathic pruritus

Background

Generalized chronic pruritus (CP) can be associated with seborrheic dermatitis and psoriasis but often can present without any noticeable diagnosis or obvious skin lesion. When not related to a clear diagnosis, CP can be characterized as idiopathic pruritus. CP is both a diagnostically and therapeutically challenging presentation due to the variety of systemic, dermatological, neurological, and psychogenic diseases that must be ruled out before diagnosing idiopathic pruritus. This presentation is often overlooked but can lead to a greatly diminished quality of life for patients who present with idiopathic generalized pruritus. The course of treatment will vary between providers and specialties, however, most dermatologists will attempt control with antihistamines, topical steroids, or oral steroids. The use of gabapentinoids for the treatment of CP is understudied. Gabapentin was initially developed as an antiepileptic that has since been approved to treat neuropathic pain and has a common off-label use in dermatology and can be used to effectively treat CP.

Case Description

Here we present a case of a 56-year-old Caucasian male who presented to the outpatient dermatology clinic with new-onset, diffuse, and intense pruritic symptoms that gradually progressed over a period of seven weeks. This case study details a patient with Idiopathic generalized pruritus previously uncontrolled that was well-controlled with the use of gabapentin after trials of other common treatments failed.

Conclusions

The understudied off-label use of gabapentin in the case of generalized chronic idiopathic pruritus should be explored and later implemented as a mainstay for patients suffering from uncontrolled CP as it was shown to completely eliminate pruritic symptoms and improve the quality of life for this patient.

Trichoscopic Features of Syphilitic Alopecia and Alopecia Areata: A Comparative Study

Background

Syphilitic alopecia (SA) and alopecia areata (AA) are two distinct conditions that frequently present diagnostic difficulties, especially when differentiating between them due to their similar clinical presentations. Trichoscopy may help in differential diagnosis, but a comparison between trichoscopic features of SA and AA is yet to be researched.

Objective

To compare trichoscopic features between SA and AA and determine their discriminative values.

Methods

Electronic medical records and trichoscopic images of patients diagnosed with SA or AA between January 2000 and February 2022 were retrieved. Trichoscopic features were statistically compared, and their discriminative values were demonstrated as sensitivity, specificity, predictive value, likelihood ratio, and area under the receiver operating characteristic curve (AUC).

Results

A total of 69 patients were included: 23 SA and 46 AA cases were matched with a 1:2 ratio. Black dots, broken hairs, pigtail hairs, exclamation mark hairs, tapered hairs, angulated hairs, and non-pigmented regrowing hairs were significantly more prevalent in AA than in SA (all P<0.05), whereas erythematous background was more prevalent in SA than in AA patients (P=0.008). Among the aforementioned trichoscopic features, exclamation mark hairs and non-pigmented regrowing hairs had a high positive likelihood ratio for AA (16.17 and 8.34, respectively); however, only exclamation mark hairs revealed high AUC (AUC=0.816).

Conclusion

Despite the presence of several similar trichoscopic features between SA and AA, trichoscopy can aid in distinguishing between the two diseases. Exclamation mark hairs are the only trichoscopic feature that can be used to differentiate patients with clinically suspicious SA from those with AA.

[Translated article] Sensitive Scalp: Diagnosis and Practical Management

Sensitive scalp is sensitive skin located on the scalp. Sensitivity is considered primary in the absence of an associated scalp disorder and secondary when caused by conditions such as psoriasis, seborrheic dermatitis, and atopic dermatitis. The clinical manifestations of primary sensitive scalp are subjective. Common presenting symptoms are burning, itching, trichodynia, and dysesthesia, often coinciding with hair loss. Clinically, the skin appears normal or red. An objective diagnosis based on laboratory or histologic findings is not possible. Triggers may be endogenous (e.g., stress and emotional or psychopathological disturbances) or exogeneous (e.g., topical products and cosmetics). Treatment must be individualized. Options include pimecrolimus, hydration with hyaluronic acid, and mesotherapy with plasma rich in growth factors.

Sensitive Scalp: Diagnosis and Practical Management

Sensitive scalp is sensitive skin located on the scalp. Sensitivity is considered primary in the absence of an associated scalp disorder and secondary when caused by conditions such as psoriasis, seborrheic dermatitis, and atopic dermatitis. The clinical manifestations of primary sensitive scalp are subjective. Common presenting symptoms are burning, itching, trichodynia, and dysesthesia, often coinciding with hair loss. Clinically, the skin appears normal or red. An objective diagnosis based on laboratory or histologic findings is not possible. Triggers may be endogenous (e.g., stress and emotional or psychopathological disturbances) or exogeneous (e.g., topical products and cosmetics). Treatment must be individualized. Options include pimecrolimus, hydration with hyaluronic acid, and mesotherapy with plasma rich in growth factors.

Liver fibrosis prevalence and risk factors in patients with psoriasis: A systematic review and meta-analysis

Background

Patients with psoriasis are more likely than matched controls in the general population to have advanced liver fibrosis; however, our understanding of these patients is limited. There is currently no systematic evaluation of the prevalence and risk factors of liver fibrosis in psoriasis patients.

Objective

To evaluate the prevalence of psoriasis patients who are at high or low risk for advanced liver fibrosis and determine the risk factors for developing liver fibrosis.

Methods

Electronic searches were conducted using the PubMed, Embase, Scopus, and Cochrane Library databases from the dates of their inception till May 2022, using the PubMed, Embase, Scopus, and Cochrane Library databases. Any observational study describing the prevalence and/or risk factors for liver fibrosis in patients with psoriasis was included.

Results

Patients with psoriasis at high risk for advanced liver fibrosis had a pooled prevalence of 9.66% [95% confidence interval (CI): 6.92-12.75%, I ² = 76.34%], whereas patients at low risk for advanced liver fibrosis had a pooled prevalence of 77.79% (95% CI: 73.23-82.05%, I ² = 85.72%). Studies that recruited methotrexate (MTX)-naïve patients found a lower prevalence of advanced liver fibrosis (4.44, 95% CI: 1.17-9.22%, I ² = 59.34%) than those that recruited MTX-user cohorts (12.25, 95% CI: 6.02-20.08%, I ² = 82.34%). Age, sex, BMI, PASI score, psoriasis duration, MTX cumulative dose, and the prevalence of obesity, MTX users, diabetes mellitus, hypertension, dyslipidemia, and metabolic syndrome were not identified as sources of heterogeneity by meta-regression analysis. The pooled odds ratios for age >50 years, BMI > 30, diabetes mellitus, hypertension, dyslipidemia, and metabolic syndrome were 2.20 (95% CI: 1.42-3.40, I ² = 0%), 3.67 (95% CI: 2.37-5.68, I ² = 48.8%), 6.23 (95% CI: 4.39-8.84, I ² = 42.4%), 2.82 (95% CI: 1.68-4.74, I ² = 0%), 3.08 (95% CI: 1.90-4.98, I ² = 0%), and 5.98 (95% CI: 3.63-9.83, I ² = 17%), respectively.

Conclusion

Approximately 10% of the population with psoriasis is at high risk for advanced liver fibrosis, while 78% are at low risk. Patients over the age of 50 with obesity, diabetes, hypertension, dyslipidemia, and/or metabolic syndrome have an increased risk of developing liver fibrosis, necessitating monitoring.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022303886], identifier [CRD42022303886].

Platelet-rich plasma in alopecia areata and primary cicatricial alopecias: A systematic review

Background

Immune-mediated alopecias (IMAs), a group of hair disorders associated with immunological reactions, remain a therapeutic challenge since available treatments are generally unfavorable with potential side effects. Platelet-rich plasma (PRP) has been recently proposed as a treatment option based on several limited-quality studies; however, there is no systematic evaluation of PRP efficacy on IMAs in the literature.

Objective

To assess PRP's effects in treating IMAs using a systematic review.

Methods

Electronic searches were conducted using PubMed, Embase, Scopus, and Cochrane Library databases. A search strategy was designed to retrieve all studies exploring PRP in treating IMAs, including alopecia areata (AA) and primary cicatricial alopecias (PCAs). In addition, all randomized and non-randomized studies reporting subjective and/or objective outcomes of alopecia treatment with PRP were included.

Results

Thirty-two studies were included, comprising 621 patients with AA and 19 patients with PCAs. PRP had superior efficacy as monotherapy in five studies, comparable to intralesional corticosteroids in six studies in AA treatment. In addition, in the analysis of PCAs, including lymphocytic and neutrophilic subtypes, PRP was efficacious in alleviating disease progression in nine studies.

Conclusion

PRP is considered a promising treatment for AA and PCAs in patients who experienced unfavorable outcomes from conventional treatment. However, its clinical application remains to be standardized, and its recommendation as a treatment for IMAs could not be ascertained due to a lack of high-quality evidence.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=353859], identifier [CRD42022353859].

Small fiber neuropathy and intractable scalp pruritus in dermatomyositis patients

Background

Scalp pruritus is a common symptom in Dermatomyositis (DM) patients. There are indications that small nerve fibers neuropathy could be involved in this symptom, however the etiology of scalp pruritus is not fully understood.

Objectives

To assess epidermal nerve fiber (ENF) density of dermatomyositis patients with scalp pruritus by biopsy by confocal microscopy and immunohistochemistry with subsequent imaging analysis.

Methods

DM patients with severe scalp pruritus from the dermatology outpatient clinic were compared to healthy volunteers. Two 4-mm scalp skin biopsies were obtained above the right ear in the parietal region and below the occipital protuberance in the occipital region. Biopsy specimens were incubated with primary antibodies to protein gene product (PGP 9.5), calcitonin gene-related peptide (CGRP), substance P (SP) were used to visualize nerve fibers (ENF) and collagen IV was used to label the epidermal basement membrane. The number of ENFs per millimeter was counted and recorded as the mean of ± SD of counts in 16 images at two micrometer increments/sections, two from each of the samples. ENF densities were compared between groups and a multiple linear regression model was applied to associated factors with ENF density.

Results

Fifteen DM patients with severe scalp pruritus and 12 healthy volunteers were included in the study. The mean number of ENF/mm in occipital region of DM group was 16.0 ± 13.9 while the control group in the same region was 99.8 ± 33.1. In parietal region the number of ENF/mm of DM group was 18.0 ± 20.7 while in control group was 50.4 ± 17.4 (p < 0.001).

Conclusion

DM patients with pruritus could have some impairment of small nerve fiber density that could explain their recalcitrant scalp pruritus.

Microbiota profiling on itchy scalp with undetermined origin

Scalp pruritus is a common skin problem that remains therapeutic challenge. The relationships between the dysbiosis of microbiota and skin diseases have caught attention recently. However, there are few reports about microbiota on itchy scalp. This study investigated scalp microbial characteristics of subjects with mild scalp pruritus of undetermined origin and preliminarily screened physiological factors and bacteria potentially related to pruritus. The pruritus severity of 17 qualified females was evaluated by Visual Analogue Scale (VAS). Microbiota collection was done at both itchy (n = 20) and non-itchy sites (n = 27) at occiput and crown of the same subject and Illumina sequencing was performed at the V3-V4 hypervariable regions of 16S rRNA. The corresponding sebum content, hydration, pH, trans-epidermal water loss, erythema index and porphyrin numbers were also measured by skin tester. We identified 3044 amplicon sequence variants from 821 genera. The itchy and non-itchy sites had different microbiota structures (p = 0.045, by multivariate analysis of variance), while there were large inter- and intra-individual variations. Both sites had Staphylococcus, Cutibacterium and Lawsonella as predominant genera, which were not significantly related to pruritus. The use of three genera Lactobacillus, Morganella and Pseudomonas, could well distinguish non-itchy from itchy groups, whereas different composition patterns existed inside each group. Our investigation indicated that though the bacterial community structure on itchy scalp was individual specific, there was difference between itchy and non-itchy sites. The study provides new insights into microbiota profiling on itchy scalp, which will help microbiota-targeted therapeutic experiment or products design for scalp pruritus.

Refractory occipital scalp pruritus treated with computed tomography-guided greater occipital nerve ablation

Greater occipital nerve blocks and thermal ablations have been widely discussed as an efficacious treatment strategy for multiple difficult to treat conditions, including occipital neuralgia, migraines, and cervicogenic headaches. Nerve blocks have also recently been presented as a method of treating neuropathic itch in the upper extremities, where pruritus occurs without visible dermatologic manifestations. We report a case of refractory occipital scalp pruritus in a patient who had excellent although time-limited response to greater occipital nerve blocks but achieved durable symptom control with CT-guided greater occipital nerve ablation.

A folliculocentric perspective of dandruff pathogenesis: Could a troublesome condition be caused by changes to a natural secretory mechanism?

Dandruff is a common scalp condition, which frequently causes psychological distress in those affected. Dandruff is considered to be caused by an interplay of several factors. However, the pathogenesis of dandruff remains under-investigated, especially with respect to the contribution of the hair follicle. As the hair follicle exhibits unique immune-modulatory properties, including the creation of an immunoinhibitory, immune-privileged milieu, we propose a novel hypothesis taking into account the role of the hair follicle. We hypothesize that the changes and imbalance of yeast and bacterial species, along with increasing proinflammatory sebum by-products, leads to the activation of immune response and inflammation. Hair follicle keratinocytes may then detect these changes in scalp microbiota resulting in the recruitment of leukocytes to the inflammation site. These changes in the scalp skin immune-microenvironment may impact hair follicle immune privilege status, which opens new avenues into exploring the role of the hair follicle in dandruff pathogenesis. Also see the video abstract here: https://youtu.be/mEZEznCYtNs.

Scalp dysaesthesia and lichen simplex chronicus: diagnostic and therapeutic update with literature review

Scalp dysaesthesia, considered a variant of the cutaneous dysaesthesia syndrome, is characterized by chronic sensory symptoms, including pruritus, pain, burning and stinging in a well‐defined location, without objective findings. Its aetiology is not well elucidated and treatment options are limited, thus it can be challenging and frustrating for both patient and physician. It can be associated with lichen simplex chronicus. In this paper, we review the literature on the pathogenetic factors, diagnostic methods and therapeutic options in the management of scalp dysaesthesia. Dissociation, cervical spine disease and muscle tension seem to be the most important pathogenetic factors. Trichoscopy, reflectance confocal microscopy and biopsy are all helpful for the diagnosis of the disease. Therapies include high‐potency topical or intralesional corticosteroids, capsaicin and topical anaesthetics, sedative antihistamines, tricyclic antidepressants, transcutaneous electric nerve stimulation, botulinum toxin and vitamin B12.