Plexiform neurofibroma masquerading as a giant congenital melanocytic nevus.

A 4-month-old male presented for a large, hypertrichotic brown patch on the upper back with several scattered 0.5-1.5 cm, round to oval, brown macules and patches on the trunk and extremities. The lesion was initially diagnosed as a giant congenital melanocytic nevus based on clinical exam and histopathology with immunohistochemical stains. The patient was later diagnosed with neurofibromatosis type 1, and the lesion on the back developed a "bag of worms" texture consistent with a plexiform neurofibroma and found to harbor a pathogenic variant in the NF1 gene. This case highlights the diagnostic challenge of differentiating these lesions and their overlapping clinical and histopathological features.

Neutrophilic Urticarial Dermatosis.

Neutrophilic urticarial dermatosis (NUD) is a rare form of dermatosis that is poorly understood. It was first described by Kieffer and colleagues as an urticarial eruption that is histopathologically characterized by a perivascular and interstitial neutrophilic infiltrate with intense leukocytoclasia and without vasculitis or dermal edema. NUD clinically presents as a chronic or recurrent eruption that consists of nonpruritic macules, papules, or plaques that are pink to reddish and that resolve within 24 hours without residual pigmentation. NUD is often associated with systemic diseases such as Schnitzler syndrome, lupus erythematosus, adult-onset Still's disease, and cryopyrin-associated periodic syndromes.

What can we learn about skin of color in dermatopathology?

As the US population becomes increasingly diverse, more patients of color seek dermatologic care and often have concerns that are unique to their skin color. Therefore, it is critically important that the knowledge gap in skin of color dermatology be urgently addressed. In addition to addressing the clinical gap in recognizing dermatologic disease in patients of color, the role of dermatopathology in bridging this gap remains unaddressed. Given the impact that skin color can have on the presentation and subsequent management of dermatologic diseases, understanding the current knowledge of the unique structural and histologic characteristics in skin of color may help give us insight on the role skin color should play in histopathologic diagnosis. In this paper, we bring insights into the role dermatopathology plays in addressing our knowledge of cutaneous disease in patients with skin of color. After we highlight issues to consider, we can begin to identify gaps in knowledge that still exist within dermatopathology that need to be addressed to ensure patients of all backgrounds receive equitable dermatologic care.

Teledermatology in practice: Report of Mayo Clinic experience.

Background: Delivery of dermatologic care through telemedicine was accelerated by the COVID-19 pandemic. We sought to analyze the teledermatology experience across Mayo Clinic's health care system to identify strengths and limitations of teledermatology. Methods: Electronic health records of dermatology televisits were reviewed from multiple U.S. Mayo Clinic sites from January 2020 through January 2021. Results: A total of 13,181 dermatology televisits were conducted in 6468 unique patients. Patients were primarily female (60.2%), and mean age of all patients was 34.1 years. Synchronous / live video conferencing visits were the most common (40.0%) telecare modality. Synchronous / live audio conferencing and asynchronous / store-and-forward visits comprised 33.0% and 27.0% of appointments. In total, 3944 televisits (29.9%) were successfully concluded via a single appointment. An in-person appointment was needed for 1693 patients (26.2%) after their initial televisit. For patients with a single televisit, synchronous / live video conferencing was the most common virtual modality (58.0% vs 32.2% of patients with multiple visits, p < 0.001). Patients needing in-person follow-up visits were slightly older than those who did not (mean [SD], 38.8 [22.3] vs 35.0 [23.6] years; p < 0.001) but without any sex-based difference. Around one-third of patients needed an in-person follow-up visit after their initial asynchronous / store-and-forward visit which was higher when compared with synchronous / live audio and video conferencing. Conclusion: Single dermatology televisits effectively managed nearly one-third of patients who did not require in-person follow-up. An initial synchronous / live video conferencing was more likely to yield a single clinical encounter, whereas asynchronous / store-and-forward visits required more in-person follow-up. Future studies are required that focus on dermatology-specific cost, diagnoses, access, quality of care, and outcomes.

High-risk adverse drug reactions: consideration of limited dialysis therapy for toxic epidermal necrolysis (TEN).

Toxic epidermal necrolysis (TEN) is a rare but often lethal drug reaction involving the skin. Treatment is often centered around suppurative care, and the mortality rate remains unacceptably high, although the clinical and epidemiological features of TEN have been well documented for decades. Recent studies have placed an emphasis on certain medications in the pathophysiology of severe TEN, and our colleagues previously reported several cases of clinical improvement in TEN patients following hemodialysis. Here, we discuss the major considerations for initiating dialysis in TEN patients. By doing so, we hope to encourage others to explore this potential avenue for treating TEN, one of the most serious medical emergencies in the field of dermatology.

Dense Lichenoid Inflammation in Paget Disease: A Diagnostic Pitfall.

ABSTRACT: Mammary Paget disease is a rare form of breast cancer, which typically presents as an eczematous plaque on the nipple or surrounding skin. It is often a clinical diagnosis that is confirmed with skin biopsy. Histologic hallmarks of mammary Paget disease include large, pleomorphic, malignant, ductal epithelial cells within the epidermis. Chronic lichenoid inflammation may be seen in the papillary dermis but is not diagnostic. Because mammary Paget disease often overlies ductal carcinoma in situ or invasive carcinoma of the breast, prompt bilateral mammography is warranted. We report a case of Paget disease of the nipple with negative breast imaging that was originally misdiagnosed due to a dense lichenoid infiltrate obscuring the neoplasm.

Diagnosis and Management of Bullous Disease.

Bullous diseases are a group of dermatoses primarily characterized by the presence of vesicles (0.1-0.9 cm) or bullae (>1 cm). There are various categories of bullous disease: allergic, autoimmune, infectious, mechanical, and metabolic. These diseases affect individuals in all decades of life, but older adults, age 65 and older, are particularly susceptible to bullous diseases of all etiologies. The incidence of these disorders is expected to increase given the advancing age of the general population. In this comprehensive review, we will outline the common bullous diseases affecting older individuals and provide an approach to evaluation and management.

Health Disparities, Clinical Trials, and the Digital Divide.

In the past few years, there have been rapid advances in technology and the use of digital tools in health care and clinical research. Although these innovations have immense potential to improve health care delivery and outcomes, there are genuine concerns related to inadvertent widening of the digital gap consequentially exacerbating health disparities. As such, it is important that we critically evaluate the impact of expansive digital transformation in medicine and clinical research on health equity. For digital solutions to truly improve the landscape of health care and clinical trial participation for all persons in an equitable way, targeted interventions to address historic injustices, structural racism, and social and digital determinants of health are essential. The urgent need to focus on interventions to promote health equity was made abundantly clear with the coronavirus disease 2019 pandemic, which magnified long-standing social and racial health disparities. Novel digital technologies present a unique opportunity to embed equity ideals into the ecosystem of health care and clinical research. In this review, we examine racial and ethnic diversity in clinical trials, historic instances of unethical research practices in biomedical research and its impact on clinical trial participation, and the digital divide in health care and clinical research, and we propose suggestions to achieve digital health equity in clinical trials. We also highlight key digital health opportunities in cardiovascular medicine and dermatology as exemplars, and we offer future directions for development and adoption of patient-centric interventions aimed at narrowing the digital divide and mitigating health inequities.

Eruptive Papules as a Cutaneous Manifestation of Metastatic Prostate Adenocarcinoma.

ABSTRACT: Cutaneous metastasis from prostate cancer is a rare manifestation, occurring in less than 1% of all cases of prostate cancer. Prostate cancer metastasis occurs most often in lymph nodes and bones. In this study, we present the case of a 55-year-old man with prostate adenocarcinoma and progressive papules on his left chest that developed shortly after androgen deprivation therapy was initiated. This case emphasizes the significance of considering cutaneous metastasis in the diagnostic differential when assessing patients with a history of cancer and the need to thoroughly evaluate these cases.

Skin of color in dermatopathology: does color matter?

Skin of color (SoC) remains an understudied and under taught area of dermatology despite its rising importance. Race and ethnicity play a particularly important role in dermatology as skin pigmentation can affect the manifestation and presentation of many common dermatoses. With this review, we seek to review pertinent differences in SoC histology, as well as highlight the histopathology of conditions more common in SoC and address inherent bias that may affect accurate dermatopathology sign out.

Collagen Vascular Diseases: A Review of Cutaneous and Systemic Lupus Erythematosus, Dermatomyositis, and Distinguishing Features in Skin of Color.

Collagen vascular diseases such as lupus erythematosus and dermatomyositis (DM) occur 2 to 3 times more often among patients with skin of color. In this article, the authors review DM and cutaneous lupus erythematosus, including acute cutaneous lupus erythematosus, subacute cutaneous lupus erythematosus, and discoid lupus erythematosus. They discuss the distinguishing features between these entities and highlight distinct presentations and management considerations in patients with skin of color to aid in prompt and correct diagnoses in this patient population.

The Role of Excision for Treatment of Chromoblastomycosis: A Cutaneous Fungal Infection Frequently Mistaken for Squamous Cell Carcinoma.

BACKGROUND: Chromoblastomycosis is an uncommon fungal infection of the skin caused by a variety of dematiaceous fungal species that is typically contracted through direct inoculation into the skin. OBJECTIVE: To collect and examine data pertaining to the clinical presentation and management of patients with chromoblastomycosis. METHODS: Through a retrospective study, a pathology medical record search was performed from January 2004 to December 2020 at a single institution. RESULTS: A total of 9 patients were identified. Seven of 9 cases occurred in solid organ transplant recipients. All cases were located on the extremities. Six of 9 cases were clinically suspected to be squamous cell carcinoma. Seven of 9 cases were treated with surgical excision. Six of 9 patients were treated with oral antifungal medication. Four of 9 patients had received combination therapy. Eight of 9 patients had no recurrence of the disease after treatment. CONCLUSION: Chromoblastomycosis presents as verrucous papules or nodules and may clinically and histopathologically mimic squamous cell carcinoma. Immunosuppression is likely a risk factor for the development of chromoblastomycosis. This study highlights the importance of clinical awareness of this disease's clinical presentation and prevalence in immunosuppressed patient populations.

Trends in Patch Testing of Black Patients: The Mayo Clinic Decade Experience (January 1, 2011, to December 31, 2020).

Background: Trends in patch testing for allergic contact dermatitis (ACD) have not been well characterized in Black patients. Despite similar incidence of ACD in Black and White patients, there are differences in allergen profiles. Understanding patch testing trends in Black patients furthers knowledge that has considerable impact on the management of ACD in the Black population. Objective: The purpose of this study was to review the results of patch testing in Black patients at Mayo Clinic over a decade. Methods: We retrospectively reviewed the results of patch testing to the standard, extended standard, or hairdresser series in 149 Black patients seen at Mayo Clinic (Rochester, MN; Scottsdale, AZ; and Jacksonville, FL) from January 1, 2011, to December 31, 2020. Results: During the 10-year period, 149 Black patients (mean age, 49.2 years [SD, 17.1 years]; female 67.1%) were patch tested at Mayo Clinic to the standard, extended standard, or hairdresser series. Most common sites of dermatitis were generalized (30.9%), hands (18.8%), leg (16.8%), trunk (16.1%), and arm (14.8%). Overall, 109 patients (73.2%) had at least 1 positive reaction and 74 patients (50%) had 2 or more positive reactions. Overall, the 10 allergens with the highest reaction rates (from highest to lowest) identified in our study population were 4-amino-2-hyroxytoluene (33.3%), thimerosal (20.4%), nickel sulfate (18.9%), methylisothiazolinone (16.5%), methyldibromo glutaronitrile (13.4%), methyldibromo glutaronitrile/phenoxyethanol (12.5%), captan (12.5%), carmine (12.5%), methylchloroisothiazolinone/methylisothiazolinone (11.5%), and hydroperoxide of linalool 1% (11.3%). Conclusions: We describe patch test results in Black patients over a decade at Mayo Clinic. The top 10 allergens were preservatives, hair dyes, and fragrances. Differing patterns of allergens may occur in Black patients due to different patterns of exposures related to cultural practices.

Clinical and histopathological features of hypereosinophilic syndrome with cutaneous involvement: The Mayo Clinic Experience.

BACKGROUND: Hypereosinophilic syndrome (HES) encompasses a group of diseases with blood hypereosinophilia and eosinophil-mediated organ dysfunction. HES-associated skin abnormalities, termed cutaneous HES (cHES) here, may influence diagnosis of HES. We sought to better define clinical and histopathological features of cHES. METHODS: We retrospectively reviewed clinical records and cutaneous histopathology of adult patients with HES evaluated at our institution from 2007 to 2018. RESULTS: Forty-one percent (61/150) patients with HES had cHES. The most common clinical morphologies were urticarial (30%) and eczematous (26%). Skin specimens most often showed a spongiotic pattern (31%) with abundant inflammation (50%) including eosinophils (85%). Two specimens (8%) showed interstitial granulomatous dermatitis, and two specimens showed eosinophilic fasciitis (8%). Vasculitis was not identified in any specimen. Eighty-four percent of patients with cHES had ≥1 other organ system involved: pulmonary 41%, ENT 26%, and nervous 23%. Sixty percent (53/89) of non-cHES patients had at least two organ systems involved. Cardiac or gastrointestinal involvement was more common in non-cHES than cHES (p < 0.05). CONCLUSION: Our review confirms that there are no specific clinical or histopathological cHES patterns, but HES should be considered in patients who have eczematous or urticarial reactions of unknown etiology and persistent peripheral hypereosinophilia.