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.

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.

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.

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.

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.

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.

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.

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.

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.

Characterization of primary cutaneous T-cell lymphoma following solid organ transplantation

BACKGROUND

Immunosuppression following solid organ transplantation is a known risk factor for the development of posttransplant lymphoproliferative disorders (PTLD). Primary cutaneous T-cell lymphoma (CTCL) occurring in the posttransplant setting is rare, which has made comprehensive understanding of this disease challenging. This study aims to further characterize the spectrum of clinicopathologic features of CTCL in solid organ transplant recipients (SOTR).

METHODS

A retrospective chart review was performed for SOTR who were diagnosed with CTCL at a multi-site academic medical center from January 1, 1998, to December 31, 2013. Eight patients fulfilled the inclusion criteria and were included in this study. Data collected included patient demographics, transplanted organ, the time between transplant and CTCL diagnosis, clinical presentation and rash morphology, a histological subtype of CTCL, immunosuppression regimens, and patient status. Twelve diagnostic skin biopsies for five patients were examined and reviewed by a board-certified dermatopathologist.

RESULTS

Six (75%) out of the eight patients were men, two (25%) were women, and the median age was 53 years. The median time from the date of transplant to the diagnosis of CTCL was 8.2 years. Transplanted organs included the liver (4), kidney (3), and heart (1). Clinical presentation varied from papulonodules, comedone-like lesions, intense pruritis, and scaly erythematous eruptions. The most common histologic presentation was folliculotropic mycosis fungoides (FMF) (7/12). Epstein-Barr virus-in situ hybridization (EBV-ISH) was negative in all specimens.

CONCLUSIONS

We emphasize the rarity of CTCL among SOTR. Although rare in the general population, the FMF subtype appears to be disproportionately seen in SOTR compared with other CTCL.

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.

Development of Cutaneous T-Cell Lymphoma Following Biologic Treatment: A Systematic Review

BACKGROUND

Cutaneous T-cell lymphoma following biologic therapy is extremely rare.

OBJECTIVE

The aim of this systematic review was to investigate the development of cutaneous T-cell lymphoma (CTCL) following treatment with a biologic agent.

METHODS

A systematic literature review was performed for patients who developed CTCL after exposure to biologic therapy. Works were limited to English language and excluded animal studies, guidelines, and protocols. Potentially eligible titles were identified using controlled vocabulary in tandem with key words. The search strategy was peer-reviewed prior to execution.

RESULTS

Twenty-eight total studies revealed sixty-two patients who developed CTCL following exposure to a biologic agent. Of these, 44% were Caucasian, and the median age at diagnosis was 56 years. Seventy-six percent of patients received biologic therapy for a primary inflammatory skin condition. Dupilumab was the most reported (42%) agent amongst the cohort. The median time from initiation of the biologic agent to diagnosis of CTCL in these cases was 4 months (range: 0-84). Mycosis fungoides (65%) and Sézary syndrome (10%) were the most common subtypes of CTCL diagnosed. Twenty-one (34%) patients were reported to be alive with disease, outcome was not reported in 21 patients (34%), ten patients (16%) were alive and in complete remission, eight patients (13%) died of disease and two patients (3%) died due to other causes.

CONCLUSION

While biologic agents may have a role in the development of CTCL, in order to definitively elucidate their role, more methodologically robust studies (such as those that utilize population databases) would need to occur.

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.

Deep learning for dermatologists: Part I. Fundamental concepts

Artificial intelligence is generating substantial interest in the field of medicine. One form of artificial intelligence, deep learning, has led to rapid advances in automated image analysis. In 2017, an algorithm demonstrated the ability to diagnose certain skin cancers from clinical photographs with the accuracy of an expert dermatologist. Subsequently, deep learning has been applied to a range of dermatology applications. Although experts will never be replaced by artificial intelligence, it will certainly affect the specialty of dermatology. In this first article of a 2-part series, the basic concepts of deep learning will be reviewed with the goal of laying the groundwork for effective communication between clinicians and technical colleagues. In part 2 of the series, the clinical applications of deep learning in dermatology will be reviewed and limitations and opportunities will be considered.

Racial disparities of delay in diagnosis and dermatologic care for hidradenitis suppurativa

Hidradenitis suppurativa is a chronic, debilitating skin disease that disproportionately affects African Americans, and care-related factors may contribute to this disparity. In this study, we investigated delay in diagnosis and dermatologic care for HS at an urban Midwestern Academic Center. A retrospective chart review of 1,190 patients with 3 or more encounters for HS between 1/1/2002 and 3/19/2019 was conducted. A total of 953 patients were included in statistical analysis. A mean (standard deviation) delay in diagnosis was 4.1 ± 7.0 years. For white patients the delay in diagnosis was 3.2 ± 6.3 years, for Black patients 4.8 ± 7.0 years, for Hispanic patients 4.7 ± 5.8 years, and for other races 4.9 ± 7.4 years (p <0.001). Among the 932 patients with known specialist visit types, 500 (53.6%) had seen dermatology including 222 (47.8%) of Black patients, 242 (59.5%) of white patients, 24 (64.9%) of Hispanic patients, and 12 (50%) patients of other races (p=0.003).White patients and Hispanic patients saw a dermatologist an average of 3.0 years after first presentation of HS and Black patients saw a dermatologist on average 5.0 years after first presentation (p=0.004). Of the patients who did see dermatology, 44.9% of Black patients, 31.6% of white patients, 23.1% of Hispanic patients, and 30.8% of other races saw surgery before dermatology (p<.001). Our results indicate that non-white patients have a longer delay in diagnosis than their white counterparts and that Black patients do not see dermatology as early in their disease course as other racial groups. Black patients also see surgery more often than white patients before seeing dermatology, which could suggest greater disease severity at presentation and diagnosis or difficult access to dermatology.

Deep learning for dermatologists: Part II. Current applications

Because of a convergence of the availability of large data sets, graphics-specific computer hardware, and important theoretical advancements, artificial intelligence has recently contributed to dramatic progress in medicine. One type of artificial intelligence known as deep learning has been particularly impactful for medical image analysis. Deep learning applications have shown promising results in dermatology and other specialties, including radiology, cardiology, and ophthalmology. The modern clinician will benefit from an understanding of the basic features of deep learning to effectively use new applications and to better gauge their utility and limitations. In this second article of a 2-part series, we review the existing and emerging clinical applications of deep learning in dermatology and discuss future opportunities and limitations. Part 1 of this series offered an introduction to the basic concepts of deep learning to facilitate effective communication between clinicians and technical experts.

Reactive granulomatous dermatitis as a clinically relevant and unifying term: a retrospective review of clinical features, associated systemic diseases, histopathology and treatment for a series of 65 patients at Mayo Clinic

BACKGROUND

Reactive granulomatous dermatitis (RGD) is an umbrella term used to describe interstitial granulomatous dermatitis (IGD), palisaded neutrophilic and granulomatous dermatitis (PNGD), and interstitial granulomatous drug eruption (IGDR).

OBJECTIVE

The aim of this study was to describe systemic associations of RGD, explore possible associations between histopathologic findings and systemic RGD associations and determine clinical relevance of RGD subtypes.

METHODS

We retrospectively studied clinical and histopathologic characteristics of patients with RGD from 1990 through 2020.

RESULTS

Of 65 patients with RGD (41 women, 24 men; median age at diagnosis, 62 years), 37 had IGD, 26 had PNGD, and 2 had IGDR. Fifty patients (76.9%) had an associated systemic condition; rheumatologic conditions were identified for 34 (52.3%) patients. The associated systemic condition occurred before RGD in approximately 75% of patients. Statistical analyses did not show significant associations between specific subtypes of RGD and systemic diseases or treatment response, and specific histopathologic findings were not predictive of an associated systemic disease.

CONCLUSIONS

Although most patients with RGD had an associated systemic condition, subtypes of RGD did not correlate with systemic associations, lending support to the use of the umbrella term RGD.

Comorbid diseases of hidradenitis suppurativa: a 15-year population-based study in Olmsted County, Minnesota, USA

BACKGROUND

Like other chronic, inflammatory skin disorders, hidradenitis suppurativa (HS) is increasingly recognized to be associated with various medical disorders.

OBJECTIVE

Using the Rochester Epidemiology Project (REP), we sought to conduct the first American population-based study examining the association between HS and various comorbid conditions.

METHODS

From the REP database, we identified patients diagnosed with HS from 2003 through 2018 who were residents of Olmsted County, Minnesota, USA, along with age- and gender-matched controls. The frequency of a wide variety of comorbid conditions was compared between the groups.

RESULTS

A total of 1160 patients with HS were identified during the study period. Compared with age- and gender-matched controls, patients with HS had a significantly higher frequency of several medical conditions, including depression, anxiety, hyperlipidemia, acne conglobata, dissecting cellulitis, pilonidal cysts, polycystic ovary syndrome, diabetes, chronic kidney disease, psoriasis, atopic dermatitis, obesity, and disordered substance use, among others.

LIMITATIONS

Our study was limited by its retrospective design.

CONCLUSIONS

Providers caring for patients with HS should consider these results, along with those of similar studies, and obtain a thorough history, comprehensive physical examination, and, potentially, laboratory testing and referral to other specialists.

African American race is a risk factor for severe hidradenitis suppurativa

BACKGROUND

African Americans face a disproportionate incidence and prevalence of hidradenitis suppurativa (HS) in the United States, but HS severity and outcomes across racial and ethnic groups have not been well-established while controlling for potentially confounding factors. In this retrospective cohort study, we investigated the associations of race and ethnicity with HS severity, emergency department (ED) visits, hospitalizations, and surgeries for HS while controlling for age, sex, body mass index (BMI), tobacco use, and insurance type.

METHODS

We reviewed 1190 patients seen at the Medical College of Wisconsin with ≥3 encounters for HS between 1/1/2002 and 3/19/2019, excluding those without race data or an encounter in which HS was treated.

RESULTS

A total of 953 patients were included; 470 patients were Black or African American non-Hispanic (49%), 39 Hispanic (4%), 418 White non-Hispanic (44%), and 26 other race or ethnicity (3%). Controlling for age, sex, BMI, tobacco use, and insurance type, Black patients had 2.8 times the odds of having Hurley stage III disease (95% CI 1.76-4.45, P < 0.001), 2.86 times the risk for experiencing an ED visit for HS (95% CI 2.12-3.88, P < 0.001), 2.25 times the risk for experiencing a hospitalization for HS (95% CI 1.42-3.56, P < 0.001), and 1.61 times the risk for experiencing a surgical encounter for HS (95% CI 1.34-1.95, P < 0.001) when compared to White patients.

CONCLUSIONS

African Americans face significant disparities in HS severity, ED visits, hospitalizations, and surgeries. The causes of these disparities must be further investigated and addressed.

Histopathology of Hidradenitis Suppurativa: A Systematic Review

Hidradenitis suppurativa (HS) is a chronic inflammatory scarring disease felt to be related to occlusion of the hair follicle unit in intertriginous areas. We perform a systematic review on HS histopathology to evaluate current knowledge and discuss future directions. PubMed and Scopus databases were searched for relevant articles published from January 1985 to January 2021 that discussed the pathology of HS. Additional articles were identified by hand-searching, which entailed manually scanning selected journals. A total of 355 citations were identified in the primary search within the main databases. Two hundred and seventy-nine articles were excluded after a review of titles, abstracts, and duplicates. Sixty-one studies did not meet the inclusion criteria or were found to be duplicates, resulting in a total of 15 articles for analysis. Three articles were hand-searched. This comprehensive systematic review of the histopathology of HS confirms a high prevalence of follicular occlusion, follicular hyperkeratosis, and hyperplasia of the follicular epithelium. These findings support the central role of follicular occlusion in the development and progression of HS while providing a potential path to directing therapeutics against follicular occlusion.

Lichen Planus Pemphigoides Associated With PD-1 and PD-L1 Inhibitors: A Case Series and Review of the Literature

ABSTRACT

Immune checkpoint inhibitors are increasingly being used in the treatment of various solid organ and hematologic malignancies. Dermatologic toxicities associated with programmed cell death protein-1 (PD-1) and programmed death ligand-1 (PD-L1) therapy have been widely reported in the literature. It is important for clinicians to be aware of these toxicities to ensure prompt recognition and treatment. Herein, we present the clinical, histopathologic, and immunofluorescence findings of 3 patients diagnosed with lichen planus pemphigoides (LPP) after treatment with anti-PD-1 inhibitors. We also reviewed the literature and summarize 7 previously reported cases of LPP associated with anti-PD-1 and anti-PD-L1 inhibitors. LPP was diagnosed at a median time of 24.4 weeks (range: 4-78 weeks) after initiation of immunotherapy. Clinical findings included papules, plaques, erosions, vesicles, and bullae on the trunk and extremities. Oral involvement was present in half the cases. Histopathologic features of immunotherapy-induced LPP included lichenoid or vacuolar interface dermatitis, the presence of eosinophils, and subepidermal bullae. Direct immunofluorescence demonstrated linear deposition of immunoglobulin G (IgG) or C3. Indirect immunofluorescence demonstrated linear IgG along basement membrane zone on monkey esophagus in 2 cases and linear IgG on the epidermal side of salt split skin in 3 cases. Serum anti-BP180 was elevated in all cases in which enzyme-linked immunosorbent assay was performed.

Association of Persistent Rubella Virus With Idiopathic Skin Granulomas in Clinically Immunocompetent Adults

Importance

Vaccine-derived and wild-type rubella virus (RuV) has been identified within granulomas in patients with inborn errors of immunity, but has not been described in granulomas of healthy adults.

Objective

To determine the association between RuV and atypical granulomatous inflammation in immune-competent adults.

Design, Setting, and Participants

This case series, conducted in US academic dermatology clinics from January 2019 to January 2021, investigated the presence of RuV in skin specimens using RuV immunofluorescent staining of paraffin-embedded tissue sections, real-time reverse-transcription polymerase chain reaction, whole-genome sequencing with phylogenetic analyses, and cell culture by the US Centers for Disease Control and Prevention. Rubella immunoglobulin G, immunoglobulin M enzyme-linked immunoassay, and viral neutralization assays were performed for the sera of immunocompetent individuals with treatment refractory cutaneous granulomas and histopathology demonstrating atypical palisaded and necrotizing granulomas. Clinical immune evaluation was performed.

Main Outcomes and Measures

Identification, genotyping, and culture of vaccine-derived and wild-type RuV within granulomatous dermatitis of otherwise clinically immune competent adults.

Results

Of the 4 total immunocompetent participants, 3 (75%) were women, and the mean (range) age was 61.5 (49.0-73.0) years. The RuV capsid protein was detected by immunohistochemistry in cutaneous granulomas. The presence of RuV RNA was confirmed by real-time reverse-transcription polymerase chain reaction in fresh-frozen skin biopsies and whole-genome sequencing. Phylogenetic analysis of the RuV sequences showed vaccine-derived RuV in 3 cases and wild-type RuV in 1. Live RuV was recovered from the affected skin in 2 participants. Immunology workup results demonstrated no primary immune deficiencies.

Conclusions and Relevance

The case series study results suggest that RuV (vaccine derived and wild type) can persist for years in cutaneous granulomas in clinically immunocompetent adults and is associated with atypical (palisaded and necrotizing type) chronic cutaneous granulomas. These findings represent a potential paradigm shift in the evaluation, workup, and management of atypical granulomatous dermatitis and raises questions regarding the potential transmissibility of persistent live RuV.

Evolution of Dupilumab-Associated Cutaneous Atypical Lymphoid Infiltrates

BACKGROUND

Observations highlighting the "unmasking" of cutaneous T-cell lymphoma after treatment with dupilumab for atopic dermatitis (AD) have been recently reported. However, there remains a paucity of literature describing the evolution of clinical and histopathological features that characterizes this phenomenon.

OBJECTIVE

To define the clinical and histopathologic evolution of atypical lymphoid infiltrates after the administration of dupilumab for AD.

METHODS

A cross-sectional study of clinical and histopathologic features in 7 consecutive patients with a diagnosis of "atypical lymphoid infiltrate" or mycosis fungoides (MF) on dupilumab for AD was performed.

RESULTS

Seven patients with atypical lymphoid infiltrates or MF in evolution after dupilumab therapy (age range 27-74 years) were reviewed. Average duration of AD before MF diagnosis was 5.7 years, and the average duration on dupilumab treatment was 9.8 months. Notable histopathologic features across predupilumab and postdupilumab biopsies included progressive increase in the densities of the atypical lymphoid infiltrates (7/7), presence of atypical epidermotropic lymphocytes (6/7), and papillary dermal fibrosis (6/7).

LIMITATIONS

Small retrospective cohort study.

CONCLUSION

These cases highlight the transformation of lymphoid infiltrates after dupilumab treatment for AD and emphasize the importance of clinical and histopathologic evaluation before and during treatment with dupilumab for treatment-refractory presumed AD.

Recent Updates in the Treatment of Erythema Multiforme

Erythema multiforme (EM) is an immune-mediated condition that classically presents with discrete targetoid lesions and can involve both mucosal and cutaneous sites. While EM is typically preceded by viral infections, most notably herpes simplex virus (HSV), and certain medications, a large portion of cases are due to an unidentifiable cause. EM can be confused with other more serious conditions like Stevens–Johnson syndrome (SJS); however, clinical research has provided significant evidence to classify EM and SJS as separate disorders. Treatment of EM is highly variable, depending on the etiology, the involvement of mucosal sites, and the chronicity (acute vs. recurring) of the disease. If the etiology or causal medication/infection is identified, then the medication is stopped and/or the infection is treated prior to initiating symptomatic treatment. Treatment for acute EM is focused on relieving symptoms with topical steroids or antihistamines. Treatment for recurrent EM is most successful when tailored to individual patients. First line treatment for recurrent EM includes both systemic and topical therapies. Systemic therapies include corticosteroid therapy and antiviral prophylaxis. Topical therapies include high-potency corticosteroids, and antiseptic or anesthetic solutions for mucosal involvement. Second-line therapies for patients who do not respond to antiviral medications include immunosuppressive agents, antibiotics, anthelmintics, and antimalarials

Exfoliative cheilitis related to psychologic factors uncovered during primary immunodeficiency evaluation

A 40-year-old previously healthy, non-atopic woman was referred for evaluation of a possible immunodeficiency disorder in the setting of an unusual erosive cheilitis and history of recurrent methicillin-resistant Staphylococcus aureus (MRSA) infection. Extensive work-up was non-diagnostic, including screening for immunologic disorders. She had failed multiple therapeutic modalities, including corticosteroid and immunosuppressive therapy. Tissue biopsy from the lip proved pivotal in demonstrating changes suggestive of factitial disease. This led to further detailed history-taking, yielding evidence of considerable psychologic distress. The patient was diagnosed with exfoliative cheilitis related to factitial disease in association with underlying untreated anxiety and psychologic trauma.

BRAF p.V600E associated poly-neoplastic syndrome

We report a male patient who developed eight different cancers between ages 57 and 64. BRAF p.V600E mutation was detected in Langerhans cell histiocytosis, chronic lymphocytic leukemia, histiocytic sarcoma, melanoma, and adenocarcinoma of the lung. It was not detected in multiple myeloma, basal cell carcinoma, and papillary thyroid cancer. BRAF p.V600E was not detected in normal skin tissue biopsy indicating that BRAF V600E was a somatic mutation affecting cancer cells. The presence of eight different cancers with five of them positive for BRAF p.V600E in a single patient is unprecedented. This type of BRAF p.V600E-associated poly-neoplastic syndrome has never been reported in the medical literature.

Post-transplant primary cutaneous peripheral T-cell lymphoma not otherwise specified in a pediatric patient

Solid organ and hematopoietic stem cell transplantation may be complicated by the development of post-transplant lymphoproliferative disorders (PTLDs). The World Health Organization categorizes PTLDs into four entities including non-destructive, monomorphic, polymorphic, and classical Hodgkin lymphoma types. The most common PTLDs are B-cell lymphomas, with T-cell lymphomas accounting for only a few cases. Cutaneous T-cell lymphomas are rarer still in post-transplant patients with primary cutaneous peripheral T-cell lymphoma being an extraordinarily rare subtype in this population. PTLDs may be aggressive and are often associated with high morbidity and mortality. Advances in medicine have led to increased awareness of PTLDs and improved diagnostic tools which assist in the diagnosis of these conditions. However, the clinical and histopathologic heterogeneity of PTLDs may make diagnosis a challenge. In the transplant patient population, the cutaneous manifestations of the lymphoproliferative disease may mimic other conditions, such as eczematous dermatitis and graft-vs-host disease. Herein, we report a case of post-transplant primary cutaneous peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) in a pediatric heart transplant patient and describe the clinical presentation and diagnostic histopathologic features.