Erythrasma: Pathogenesis and Diagnostic Challenges.

Erythrasma is a common chronic superficial bacterial infection caused by Corynebacterium minutissimum, a lipophilic, diphtheroid, filamentous, gram-positive bacillus and normal inhabitant of the skin flora. Commonly found in intertriginous spaces, this bacterium releases a porphyrin that causes lesions to fluoresce under a Wood's lamp, aiding diagnosis. Despite its clinical relevance, the pathogenesis remains understudied. We present a case of a 43-year-old woman with a history of hypertension, type 2 diabetes mellitus, and obesity who exhibited an erythematous eczematous plaque with characteristic coral-red fluorescence under Wood's lamp. The diagnosis was confirmed through negative skin scrapings for candidiasis and dermatophytosis. A two-week course of topical clindamycin resulted in complete resolution. Given the condition's frequent coexistence with other pathologies, accurate diagnosis and effective treatment are essential. Topical treatments are usually more convenient. The hypothesis that hydrophobic and lipophilic interactions in intertriginous areas contribute to the pathogenesis of erythrasma requires further experimental validation.

Novel imaging techniques for tumor margin detection in basal cell carcinoma: a systematic scoping review of FDA and EMA-approved imaging modalities.

Mohs micrographic surgery (MMS) is the gold standard for removing basal cell carcinomas (BCCs) due to its ability to guarantee 100% margin evaluation through frozen section histopathology, offering the highest cure rate among current treatments. However, noninvasive imaging technologies have emerged as promising alternatives to clinical assessment for defining presurgical margins. This systematic scoping review examines the efficacy of these imaging modalities, focusing on those approved for clinical use by the United States Food and Drug Administration (FDA) or the European Medicines Agency (EMA). A systematic search of EMBASE, Scopus, PubMed, and the Cochrane Public Library databases identified 11 relevant studies out of 2123 records, encompassing 644 lesions across five imaging techniques. The findings suggest that dermoscopy, high-frequency ultrasound (HFUS), optical coherence tomography (OCT), line-field optical coherence tomography (LC-OCT), and reflectance confocal microscopy (RCM) show potential in detecting BCC margins, which could enhance MMS by providing better preoperative planning, informing patients of expected defect size, aiding in reconstruction decisions, and reducing overall procedure costs. This review discusses the benefits and limitations of each technique, offering insights into how these innovations could influence the future of BCC management. Emerging imaging techniques could enhance MMS by improving BCC margin assessment and reducing costs. Their adoption will depend on price and ease of use.

Overlapping large facial nevus spilus and nevus of Ota: A case report diagnosed with dermoscopy and reflectance confocal microscopy.

We report a rare case of large facial hyperpigmentation in a 25-year-old female. Starting one month after birth, the patient developed a blue-brown patch on the right side of her face, interspersed with black macules and papules. As she aged, the lesion progressively enlarged and darkened, eventually covering the entire right side of her face. Dermoscopic and reflectance confocal microscopy examinations indicated nevus spilus in some areas and nevus of Ota in others, leading to a definitive diagnosis of overlapping nevus spilus and nevus of Ota. With no signs of malignant transformation on clinical or imaging examination, successful treatment was achieved using Q-switched alexandrite laser without any adverse effects. Our case underscores the critical value of dermoscopy and reflectance confocal microscopy in diagnosing rare facial pigmentary conditions, as we compare the imaging characteristics of nevus spilus, nevus of Ota, and similar conditions, alongside their clinical and histopathological correlations. Furthermore, our findings highlight the significant role of imaging examinations in monitoring malignancy and guiding treatment decisions.

Lentigo Maligna and Lentigo Maligna Melanoma of the External Ear: Clinical and Dermoscopic Features of 19 Patients.

External ear lentigo maligna/lentigo melanoma (LM/LMM) represents approximately 1%-4% of all primary cutaneous melanomas. Over the past 20 years, dermoscopy has proven highly effective in early detection of LM/LMM, with recent studies identifying perifollicular linear projections (PLP) as a specific diagnostic criterion for early LM. However, in clinical practice, LM and LMM turn out to be very difficult to distinguish based on dermoscopic findings. Therefore, our retrospective monocentric study aimed to investigate dermoscopic characteristics, as well as the epidemiological and clinical data of 19 patients diagnosed with the external ear (EE) LM/LMM at the Oncologic Dermatology Unit in Bologna. Dermoscopic images were obtained using the FotoFinder Medicam 800HD, and specific criteria validated by the International Dermoscopy Society (IDS) for atypical pigmented facial lesions were assessed. Fisher's exact test was primarily used for statistical comparisons. As results, most of the patients were male (74%) with an average age (± SD) at diagnosis of 69.8 (± 15.1) years old. LMM appeared more commonly observed in elderly patients as compared to LM (mean 71.6 vs. 66.7, p = 0.514), presenting as pigmented macule (89.5%) of the ear lobule (23.9%). A statistically significant difference (p = 0.01) of tumour' diameter between LMM and LM was reported with the first resulting more than twice the size of the latter. Concerning dermoscopic findings, asymmetric pigmented follicles, obliteration of the follicular openings and grey circles were more frequently observed in LMM compared to LM (63.2% vs. 31.6%; 63.2% vs. 26.3%; 47.4% vs. 15.8%, respectively).

The Accuracy of Skin Cancer Detection Rates with the Implementation of Dermoscopy Among Dermatology Clinicians: A Scoping Review.

Objective: The goal is to determine if the implementation of dermoscopy improves the accuracy, specificity, and sensitivity rates of skin cancer detection among dermatology clinicians and identify the optimal training method for dermatology clinicians to become proficient in dermoscopy. Methods: A comprehensive search through the A.T. Still Memorial Library, including the electronic health databases PubMed, Scopus, UpToDate, and CINAHL, was performed. Google Scholar search results were sorted by relevance, and the first 30 pages were included within the search due to the large quantity of results. The search keywords included "skin cancer diagnosis," "accuracy," "detection," "dermoscopy," and "dermatologists." The search was performed in July 2023. The date limitations used within the search parameters ranged from 2017 to 2023 to review the past seven years of publications. The search evaluated reference lists and encompassed those that met the inclusion and exclusion criteria. Dermatologists, dermatology physician assistants, dermatology nurse practitioners, and primary care practitioners were eligible for inclusion. The search included literature from any country. The English language was the only language permitted within the search. Gray literature was included in the search using news, press release, and MedRxiv. Results: A total of 28 articles met the inclusion criteria. All of the articles included were from peer-reviewed sources and in the English language. The articles came from 10 different countries of origin and were published from 2017 to 2023. The main results of the scoping review discovered that the use of dermoscopy improves the accuracy of skin cancer diagnosis. The results also demonstrated that dermoscopy training is highly variable; multiple different types of diagnostic algorithms are used in the professional medical education systems of the 10 countries included within the scoping review. The dermoscopy training algorithms recommended include pattern analysis, 7-point checklist, Menzies method, Triage Amalgamated Dermoscopy Algorithm, Australasian College of Dermatology Dermoscopy Course, 3-point checklist, ABCD rule, Skin Imaging College of China, and no particular algorithm. Of these, the three most commonly recommended included the 7-point checklist, Menzies method, and pattern analysis. Conclusion: The results demonstrated that dermoscopy improves the accuracy of skin cancer diagnosis for dermatology clinicians and primary care providers. Key implications of these findings for practice include earlier skin cancer detection, which can lead to reduced rates of morbidity and mortality, reduced overall healthcare costs, reduced number of benign lesions biopsied, and improved patient outcomes.

Trichoscopy of Lichen Planopilaris in Black Scalp: A Literature Review.

Background: Lichen planopilaris (LPP) manifests as uni or multifocal patches of scarring alopecia across the scalp. Its symptoms include pruritus, trichodynia, and burning. Trichoscopy is a critical tool for early disease detection. In African descendants, LPP poses additional diagnostic challenges, given the black scalp peculiarities. These specific features include lower hair density, slower growth, and structural differences, compared to Caucasians. Moreover, the healthy black scalp may show distinctive features such as a honeycomb-pigmented network and sparse pinpoint white dots. Summary: In individuals of African descent, the most prevalent scarring alopecia is Central Centrifugal Cicatricial Alopecia, an important differential diagnosis for LPP in this population. LPP trichoscopy in the black scalp reveals unique features such as perifollicular erythema in the early stages, which often manifests as hyperpigmentation. This study aimed to review the literature on trichoscopy findings in LPP on black scalp categorizing them into distinct stages and highlighting their unique yet understudied characteristics. Key Messages: Despite not being as prevalent as nonscarring alopecias and not so frequent in the black scalp, LPP's aesthetic and devastating psychosocial impact raise concerns. Therefore, early recognition is paramount to halt the progress of LPP, mitigate its psychosocial impact, and prevent misdiagnosis.

Trichoscopy of Central Centrifugal Cicatricial Alopecia: A Retrospective Study and Literature Review.

Introduction: Central centrifugal cicatricial alopecia (CCCA) is the most common cause of scarring alopecia in middle-aged black women. Trichoscopy is a noninvasive tool for diagnosis and follow-up of hair and scalp disorders. To date, limited studies have focused on its applicability to CCCA in existing literature. Methods: The present study aimed to describe the trichoscopic findings of 11 dark-skinned women with confirmed CCCA and provide a comprehensive discussion of our current knowledge regarding trichoscopy of this disease through a literature review. A thorough understanding of CCCA trichoscopy holds significant promise for early confirmation and treatment. Conclusion: By doing so, it is possible to mitigate the development of complications and alleviate the subsequent impact on patients' quality of life.

Photoplethysmography-Based Angiography of Skin Tumors in Arbitrary Areas of Human Body.

Noninvasive, rapid, and robust diagnostic techniques for clinical screening of tumors located in arbitrary areas of the human body are in demand. To address this challenge, we analyzed the feasibility of photoplethysmography-based angiography for assessing vascular structures within malignant and benign tumors. The proposed hardware and software were approved in a clinical study involving 30 patients with tumors located in the legs, torso, arms, and head. High-contrast and detailed vessel maps within both benign and malignant tumors were obtained. We demonstrated that capillary maps are consistent and can be interpreted using well-established dermoscopic criteria for vascular morphology. Vessel mapping provides valuable details, which may not be available in dermoscopic images and can aid in determining whether a tumor is benign or malignant. We believe that the proposed approach may become a valuable tool in the preliminary cancer diagnosis and is suitable for large-scale screening.

The Role of Digital Dermoscopy and Follow-Up in the Detection of Amelanotic/Hypomelanotic Melanoma in a Group of High-Risk Patients-Is It Useful?

The prognosis, outcome, and overall survival of melanoma patients improve with early diagnosis which has been facilitated in the past few decades with the introduction of dermoscopy. Further advancements in dermoscopic research, coupled with skilled, educated dermatologists in dermoscopy, have contributed to timely diagnoses. However, detecting amelanotic and hypomelanotic melanoma remains a challenge even to the most skilled experts because these melanomas can mimic inflammatory diseases, numerous benign lesions, and non-melanoma skin cancers. The list of the possible differential diagnoses can be long. Melanoma prediction without the pigment relies only on vascular criteria, and all classic dermoscopic algorithms have failed to fulfill our expectations. In fact, the diagnosis of amelanotic and hypomelanotic melanomas is very challenging, which is why every tool in detecting these lesions is of significance. This review aims to explore the current knowledge and the literature on the possibility of detecting amelanotic/hypomelanotic melanomas using sequential monitoring with digital dermoscopy and total body skin photography.

Non-invasive techniques in the clinical diagnosis of cutaneous lymphomas.

In clinical practice, cutaneous lymphomas can be challenging to diagnose or even suspect because they mimic a variety of other inflammatory and neoplastic dermatological conditions. Support for non-invasive skin analysis methods like reflectance confocal microscopy and dermoscopy is still anecdotic. Practically speaking, a deeper and more comprehensive study with a larger number of cases focusing on the effective usefulness of non-invasive techniques should be taken into consideration because they have demonstrated the ability to identify macro and micro features supporting the clinical suspicion of lymphomas, as well as being useful for differential diagnosis and supporting the selection of the biopsy site. The author provides a brief and narrative synopsis of the reflectance confocal microscopy and dermoscopy characteristics of cutaneous lymphomas in this manuscript.

Photographic scale for the characterization of actinic keratosis through reflectance confocal microscopy: a quantitative approach to cellular transformation.

Background: Actinic keratosis (AK) is a highly prevalent pre-cancerous skin lesion that often leads to cutaneous squamous cell carcinoma. There are different stages of evolution of the disease and several features that characterize keratosis. This study aimed to develop a qualitative and quantitative visual diagnostic tool to facilitate the identification of the characteristics and severity of the main cellular attributes of AK and to show its applicability in evaluating the evolution or treatment through image analysis. Methods: Literature research on the main scientific databases and in the institute's database was carried out to gather all the different levels of cellular transformation. To validate the scale, a preliminary characterization study was carried out with 21 subjects who had clinically diagnosed AK lesions to classify the attributes in each skin layer and test the accuracy of the diagnosis of the scale. Afterward, and to show the possibility of a follow-up with a topical treatment, the subjects were divided into two treatment groups, receiving either a cream formulation containing retinoic acid, or a placebo formula. The evaluation was carried out through confocal reflectance microscopy and a digital camera with dermoscopic quality before and after 90 days of treatment. Results: A table detailing the 18 attributes of AK, and a photographic scale containing RCM images graded by scores established for each characteristic and the frequency of spreading were developed. The results of the validation presented good repeatability, correlation with clinical evaluation, and capacity for differentiating treatments demonstrated by the significant improvement after topical treatment by the reduction of the score for 10 out of the 18 attributes. The preliminary study, evaluated by the detailed transformation scale highlights important differences in the subclinical approach that allows a deeper evaluation of the aspects of the lesion's re-incidence even after fully treated skin sites. Conclusion: This study brings an innovative method based on RCM, to assist in the quantification of cell transformation level, provide early diagnosis, and deliver a powerful treatment evaluation tool to provide smoother treatment, as well as prevent re-incidence in the cases.

Prevalence of onychomycosis among psoriasis patients: a clinico-mycological and dermoscopic comparative cross sectional study.

Onychomycosis, a nail infection caused by dermatophytes, yeast, and molds makes up roughly half of all onychopathies and is the most prevalent nail condition in the world. Clinically, nail psoriasis and onychomycosis can frequently be difficult to distinguish from one another. To assess the prevalence of onychomycosis in patients with psoriasis. Fifty patients with psoriasis associated with nail disease were included in this study. After taking clinical history, nail samples were gathered for dermoscopic inspection, culture, direct microscopy with 20% KOH solution, and nail clipping with PAS stain. Of the 50 patients recruited, 43 were males and 7 were females, with mean age 6-71 years (mean ± SD 44.06 ± 16.2). Eleven patients (22%) tested positive for onychomycosis. Dermatophytes were isolated from 2% of patients, yeast from 14% of patients, and non-dermatophytic mold from 38% of patients. Histopathological results revealed fungal hyphae and spores in 18% of patients. The most prevalent dermoscopic sign in psoriatic patients with onychomycosis was spikes (81.8%) with statistical significance (P-value < 0.001), while nail pitting was the most prevalent dermoscopic feature in nail psoriasis. This study lays the way for an accurate diagnosis of nail lesions by highlighting the significance of cooperation between mycology, histology, and dermoscopy in the diagnosis of onychomycosis in patients with nail psoriasis.

Computerizing the first step of the two-step algorithm in dermoscopy: A convolutional neural network for differentiating melanocytic from non-melanocytic skin lesions.

IMPORTANCE: Convolutional neural networks (CNN) have shown performance equal to trained dermatologists in differentiating benign from malignant skin lesions. To improve clinicians' management decisions, additional classifications into diagnostic categories might be helpful. METHODS: A convenience sample of 100 pigmented/non-pigmented skin lesions was used for a cross-sectional two-level reader study including 96 dermatologists (level I: dermoscopy only; level II: clinical close-up images, dermoscopy, and textual information). Dermoscopic images were classified by a binary CNN trained to differentiate melanocytic from non-melanocytic lesions (FotoFinder Systems, Bad Birnbach, Germany). Primary endpoint was the accuracy of the CNN's classification in comparison with dermatologists reviewing level-II information. Secondary endpoints included dermatologists' accuracies according to their level of experience and the CNN's area under the curve (AUC) of receiver operating characteristics (ROC). RESULTS: The CNN revealed an accuracy and ROC AUC with corresponding 95 % confidence intervals (CI) of 91.0 % (83.8 % to 95.2 %) and 0.981 (0.962 to 1). In level I, dermatologists showed a mean accuracy of 83.7 % (82.5 % to 84.8 %). With level II information, the accuracy improved to 87.8 % (86.7 % to 88.9 %; p < 0.001). When comparing accuracies of CNN and dermatologists in level II, the CNN's accuracy was higher (91.0 % versus 87.8 %, p < 0.001). For experts with level II information results were on par with the CNN (91.0 % versus 90.4 %, p = 0.368). CONCLUSIONS: The tested CNN accurately differentiated melanocytic from non-melanocytic skin lesions and outperformed dermatologists. The CNN may support clinicians and could be used in an ensemble approach combined with other CNN models.

The Role of Artificial Intelligence in the Diagnosis of Melanoma.

The incidence of melanoma, the most aggressive form of skin cancer, continues to rise globally, particularly among fair-skinned populations (type I and II). Early detection is crucial for improving patient outcomes, and recent advancements in artificial intelligence (AI) have shown promise in enhancing the accuracy and efficiency of melanoma diagnosis and management. This review examines the role of AI in skin lesion diagnostics, highlighting two main approaches: machine learning, particularly convolutional neural networks (CNNs), and expert systems. AI techniques have demonstrated high accuracy in classifying dermoscopic images, often matching or surpassing dermatologists' performance. Integrating AI into dermatology has improved tasks, such as lesion classification, segmentation, and risk prediction, facilitating earlier and more accurate interventions. Despite these advancements, challenges remain, including biases in training data, interpretability issues, and integration of AI into clinical workflows. Ensuring diverse data representation and maintaining high standards of image quality are essential for reliable AI performance. Future directions involve the development of more sophisticated models, such as vision-language and multimodal models, and federated learning to address data privacy and generalizability concerns. Continuous validation and ethical integration of AI into clinical practice are vital for realizing its full potential for improving melanoma diagnosis and patient care.

A Rare Presentation of Becker's Nevus on the Lower Extremity With Dermoscopic Features: A Case Report.

Becker's nevus (BN) is a unilateral epidermal hamartoma that presents as a hyperpigmented and hypertrichotic lesion, typically appearing during adolescence. While BN frequently occurs on the upper trunk and proximal upper limbs, its manifestation on the lower limb is rare. Dermoscopy serves as a helpful diagnostic tool alongside clinical examination, revealing features such as pigment networks, hypertrophic follicles, and distinct skin furrows. We presented a case of a 17-year-old boy with typical dermoscopic features of BN located on the lower extremity. Although there is no definitive treatment for BN, most therapeutic interventions are primarily aimed at improving cosmetic appearance. In cases like ours, where the patient is not concerned about the cosmetic aspect, treatment may not be necessary. Laser therapies, in particular, have been shown to be effective in treating BN. There are no reported cases of malignant transformation in the literature. While associations with conditions such as malignant melanoma, vitiligo, and various skin appendages have been documented in case reports, BN is generally considered a benign clinical condition in most patients.

Basosquamous Carcinoma: A Rare Entity With an Atypical Presentation.

Basosquamous carcinoma (BSC) is a rare entity of basal cell carcinomas. It is described as being nosologically at the border between a squamous cell carcinoma and a basal cell carcinoma, thus sharing characteristics of both entities. The frequency of this pathology remains low with a few cases reported in the literature. We report the observation of a basosquamous carcinoma with a particular topography on the pulp of the left fifth finger. A histological examination confirmed the diagnosis. Locoregional and general extension studies were negative. Management consisted of surgical resection.

Reflectance Confocal Microscopy and Dermoscopy for the Diagnosis of Solitary Hypopigmented Pink Lesions: A Narrative Review.

Diagnosing solitary pink skin lesions poses a significant challenge due to the scarcity of specific clinical and dermoscopic criteria. Several benign lesions, such as cherry angioma, clear cell acanthoma, dermal nevus, keloid, hypertrophic scar, and Spitz nevus, often exhibit similar clinical and dermoscopic features. This similarity extends to some malignant lesions, including basal cell carcinoma, actinic keratosis, and amelanotic melanoma, making differentiation difficult. Recent studies highlight the enhanced diagnostic accuracy of reflectance confocal microscopy (RCM), which offers increased sensitivity and specificity compared to dermoscopy alone for diagnosing skin cancer. This study aims to summarize the application of dermoscopy and RCM in distinguishing between benign and malignant pinkish-reddish skin lesions. The integration of RCM with traditional dermoscopic techniques improves the ability to accurately identify and differentiate these lesions. However, it is crucial to note that for any suspicious lesions, a final diagnosis must be confirmed through surgical excision and histopathological evaluation. This comprehensive approach ensures accurate diagnosis and appropriate treatment, highlighting the importance of combining advanced imaging techniques in clinical practice.

The Impact of Melanoma Imaging Biomarker Cues on Detection Sensitivity and Specificity in Melanoma versus Clinically Atypical Nevi.

Incorporation of dermoscopy and artificial intelligence (AI) is improving healthcare professionals' ability to diagnose melanoma earlier, but these algorithms often suffer from a "black box" issue, where decision-making processes are not transparent, limiting their utility for training healthcare providers. To address this, an automated approach for generating melanoma imaging biomarker cues (IBCs), which mimics the screening cues used by expert dermoscopists, was developed. This study created a one-minute learning environment where dermatologists adopted a sensory cue integration algorithm to combine a single IBC with a risk score built on many IBCs, then immediately tested their performance in differentiating melanoma from benign nevi. Ten participants evaluated 78 dermoscopic images, comprised of 39 melanomas and 39 nevi, first without IBCs and then with IBCs. Participants classified each image as melanoma or nevus in both experimental conditions, enabling direct comparative analysis through paired data. With IBCs, average sensitivity improved significantly from 73.69% to 81.57% (p = 0.0051), and the average specificity improved from 60.50% to 67.25% (p = 0.059) for the diagnosis of melanoma. The index of discriminability (d') increased significantly by 0.47 (p = 0.002). Therefore, the incorporation of IBCs can significantly improve physicians' sensitivity in melanoma diagnosis. While more research is needed to validate this approach across other healthcare providers, its use may positively impact melanoma screening practices.