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Open Access Publications from the University of California

Dermatology Online Journal

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Dermatology Online Journal is an open-access, refereed publication intended to meet reference and education needs of the international dermatology community since 1995. Dermatology Online Journal is supported by the Department of Dermatology UC Davis, and by the Northern California Veterans Administration.

Volume 26, Issue 11, 2020


Is Morgellons an organic disease? structural and functional abnormalities implicated in the pathophysiology of delusional infestation

Little is known about the pathophysiology of delusional infestation (DI), a psychodermatologic condition in which patients have a fixed, false belief of being infested with parasites or inanimate material in their skin, despite lack of objective evidence. Because some delusional states, such as schizophrenia and psychotic state in bipolar disorder have been found to be associated with brain structural and functional abnormalities, a literature review was conducted to summarize available data on structural and functional abnormalities that are found to be associated with DI. A review of the literature found cases of brain imaging studies in patients with primary DI, as well as patients with secondary DI. Accumulating evidence from the studies reviewed suggests that dysfunction of the fronto-striato-thalamo-parietal network may explain how delusions manifest in DI and suggest that DI has an organic etiology. Abnormalities in the striato-thalamo-parietal network may cause false sensations of infestation through dysfunction in visuo-tactile regulation, whereas abnormalities in the frontal region may impair judgement. Delusional infestation patients also exhibit increased activation of brain structures implicated in itch processing. Furthermore, patients at high risk for cerebrovascular disease who present with secondary DI may benefit from brain imaging studies to rule out brain ischemic insult.

Development of a hidradenitis suppurativa patient decision aid

Background: Patient decision aids (PDAs) are tools that facilitate informed shared decision-making between patients and health care providers. To address a previously identified need in treatment decision-making in hidradenitis suppurativa (HS), we developed an HS-PDA.Methods: Development of the HS-PDA was based on International Patient Decision Aids Standards. Evidence was derived from the North American Clinical Management Guidelines for HS.Results: Content from guidelines was transformed into patient-friendly language and reviewed by three physicians and two patient representatives. Feedback on HS-PDA content, presentation and practicality was obtained from 7 HS patients and 5 physicians. Revisions were made following thematic analysis. All patients felt the content on treatment options contained the right amount of information and 5 found it helpful to see these options contextualized to their values. Each stated they would use the HS-PDA during treatment decision-making. Three and four physicians respectively indicated the content was accurate and language was patient-friendly.Limitations: Small sample sizes may limit generalizability.Conclusion: This HS-PDA was developed in accordance with international standards based on current HS guidelines with input from patients and physicians. It is available online without cost.

The 100 most influential skin cancer publications: a citation analysis

Background: As skin cancer is the most common cancer in the U.S., many publications focus on cutaneous malignancies. The objective was to identify and analyze the 100 most-cited articles pertaining to skin cancers to provide clarity on past, and insight for future research. Methods: Using a two-stage search of Thomson Reuters Web of Science database, the 100 most-cited skin cancer articles between 1945 and 2018 were identified and analyzed. Results: The articles were cited an average total of 558.49 times (range: 259 to 3429). There were relatively few significant publications until 1988. Linear correlation revealed that journal impact factor was not correlated with average number of citations per year per article (R2=0.06). Molecular pathogenesis and UV exposure were the most common topics. The topics that received the highest average citations per year per article were prevention (50.44 citations per year), diagnosis (47.32 citations per year), and management (41.37 citations per year). Basic science articles accounted for the most publications, followed by narrative literature reviews. Conclusions: These results may indicate that future publications with similar characteristics are more likely to be cited and thus, more influential.


Saccharomyces cerevisiae as a skin physiology, pathology, and treatment model

Saccharomyces cerevisiae serves as a useful model in experimental biology. Within dermatology research, several studies have examined this organism's role in skin physiology, pathology, and treatment. Saccharomyces cerevisiae has been used to explore the mechanisms of melanogenesis as its extract inhibits key enzymes involved in melanogenesis and melanosome transfer. Additionally, the lack of probiotic intestinal Saccharomyces cerevisiae has been associated with psoriasis, potentially related to the anti-inflammatory effects of the yeast. Furthermore, antibodies against Saccharomyces cerevisiae have been observed in skin conditions, including atopic dermatitis. Saccharomyces cerevisiae may even cause skin infections, such as septic emboli in a patient with acute myelogenous leukemia. Lastly, Saccharomyces cerevisiae has potential use in vaccine development against melanoma and is utilized to study various treatment modalities such as zinc pyrithione, an ingredient often used in anti-dandruff shampoo.

Challenges of Teledermatology: Lessons Learned During COVID-19 Pandemic

The COVID-19 pandemic required a transition to telemedicine to limit viral spread. Dermatology seems particularly well-suited for telemedicine, however, this pandemic transformed teledermatology into the predominant means of delivering care. Providers are limited in their ability to promptly and accurately manage disease without access to in-person tools. This monumental switch to teledermatology may disadvantage certain patient populations, including those with limited technological literacy (such as the elderly) or access to the internet. Dermatologists must acknowledge these limitations and recognize the consequences of severely limited in-person visits over a prolonged period of time.

Health policy literacy among U.S. dermatology residents: characterizing past experiences and future goals

Background: Health policy knowledge is critical in today's healthcare environment; efforts to understand dermatology residents' health policy literacy and education on policy reforms pertaining to dermatology practice are limited. Methods: A 25-question electronic survey was administered to current U.S. dermatology residents in ACGME-accredited residencies to assess health policy education/experiences, career goals, and familiarity with current issues in health policy and dermatology. Results: There were 46 respondents of equal gender and training stage distribution. Of these, 67% and 30% reported health policy instruction in medical school and residency, respectively; 17% reported no prior instruction. Additionally, 50% and 31% intended to pursue academic medicine and private practice, respectively. Although most believed dermatology careers to be compatible with non-clinical endeavors (organized medicine leadership, policy reform, political/legislative advocacy, elected office), few intended to pursue such endeavors. Fewer than 50% of respondents reported familiarity with health legislation, reimbursement models, and the American Academy of Dermatology Association's 2018 advocacy priorities. Conclusions: Although some dermatology residents have prior health policy education and/or receive training in residency, there remain gaps in their knowledge and preparation to face current healthcare issues. Medical schools and residencies should address such gaps and provide health policy opportunities to ensure trainees' future success.

The ethical foundation for honesty and the focused use of deception in dermatology

Physicians have a fiduciary duty to be honest and to act in the patients' best interest. There are times when these two duties conflict. Honesty is paramount in supporting the physician-patient relationship and loss of patient trust is devastating. Furthermore, even minor deception can suggest a return to the physician authoritarianism of the past century that has been decried by modern ethicists. Nonetheless, circumstances can arise in which good judgement may require less than complete honesty to avoid harm to the patient. If the benefit for the patient is large and the risk from deception is small, thoughtful application of minor deception could be designed to benefit patients. Of course, research is required to fully assess this strategy.

Case Report

Extraocular sebaceous carcinoma as a rapidly growing back mass: a case report

Sebaceous carcinoma is a rare cutaneous malignancy that frequently mimics other dermatologic conditions. Extraocular subtypes are uncommon, but when present are frequently located in the head and neck region. Herein, we present a patient with a rapidly growing upper back mass eventually diagnosed as sebaceous carcinoma and managed with wide surgical excision. Currently, sparse literature exists to guide management of such patients. This case highlights not only the diagnostic challenges of sebaceous carcinoma, but also the need for further studies to investigate therapeutic interventions and long-term outcomes.

Case Presentation

Occipital alopecia in a young man

Lipedematous alopecia is a rare, non-androgenic form of alopecia that is challenging to diagnose, often requiring clinical-pathological correlation. The condition has been reported predominantly in African-American females, but more recently has been described in a broader demographic [1,2]. We describe a rare case of a young Caucasian man with isolated lipedematous alopecia who presented with a boggy, erythematous plaque with alopecia of the occipital scalp and subcutaneous thickening with lymphocytic dermal infiltrate and decreased anagen hairs on histology.

Acquired Darier disease in a patient with metastatic prostate cancer: a paraneoplastic process?

Darier disease is considered a hereditary acantholytic dermatosis that is inherited in an autosomal dominant manner and usually manifests in the first or second decade of life. We describe a 62-year-old man with an acquired variant of Darier disease after a recent diagnosis of metastatic prostate cancer. We discuss and postulate a novel mechanism for this unusual presentation.

Frontal fibrosing alopecia with involvement of the central hair part: distribution of hair loss corresponding to areas of sunscreen application

Frontal fibrosing alopecia (FFA) typically presents with band-like scarring alopecia in the frontal and temporal hairline along with eyebrow loss. Although this type of hair loss is being seen with increased frequency worldwide, the etiology of the condition is unknown. Studies have suggested a potential environmental role with moisturizers and sunscreens being possible triggers. Herein, we present a 42-year-old woman with a biopsy-proven diagnosis of frontal fibrosing alopecia. In addition to the typical pattern, she also had a striking linear patch of hair loss along her central part. This was an area where she regularly applied sunscreen for many years. Although a causative role for sunscreen ingredients in the development of FFA has not been proven, the evidence accumulated thus far, including our suggestive case, substantiates the need for further study. Additionally, increasing awareness of this potential effect leading to appropriate counseling regarding cessation of possible triggers may be critical for the prevention of further hair loss.

Widespread pustular eruption following probiotic use

A 26-year-old woman with Crohn disease and palmoplantar psoriasis on ustekinumab presented with a diffuse and intensely pruritic rash with a few pin-point pustules within days after initiation of an over-the-counter Align brand probiotic. Biopsy revealed psoriasiform and spongiotic dermatitis with spongiform subcorneal pustules and scattered eosinophils, consistent with acute generalized exanthematous pustulosis. Our case highlights a unique presentation of acute generalized exanthematous pustulosis following probiotic exposure with fewer than usual pustular lesions. IL23 suppression by ustekinumab may have contributed to the patient's reduced pustular presentation.

Iatrogenic cutaneous graft versus host disease.

A 65-year-old man with acute myeloid leukemia 6 was treated by bone marrow allograft, developed a systemic classic chronic graft versus host disease with hepatic, rheumatologic, ophthalmic, and muco-cutaneous involvement. He received systemic corticosteroid, ruxolitinib and extracorporeal photopheresis which resulted in complete remission. During follow-up the patient presented with viral cutaneous warts on his neck and submandibular area. After various subsequent topical treatments, he developed localized cutaneous GVHD without any general GVHD reactivation symptoms. To the best of our knowledge, there has been no description in the literature of a graft versus host disease developing after local immunomodulatory or cytotoxic treatments. Topical therapies are commonly used by dermatologists for superficial skin cancers and some viral skin lesions, in high risk populations such as organ transplant patients with regular follow-up.Practitioners should be made aware of a possible localized cutaneous GVHD reactivation induced by Koebner phenomenon after local therapy.

Post-traumatic lip lesion mimicking rhabdomyomatous mesenchymal hamartoma in a pediatric patient

We report a 7-year-old boy who presented with a nodule on the upper lip. A previous clinical history of mechanical trauma in the lesional area had been noted. After surgical excision, microscopy revealed fibrocollagenous fascicles associated with neurovascular bundles and skeletal striated muscle fibers in diffuse subepithelial distribution, suggesting rhabdomyomatous mesenchymal hamartoma. However, strict clinicopathological correlation favored a healing process with trapped striated skeletal muscle tissue. After three years of follow-up, an improvement in the aesthetic appearance of the upper lip was observed. To the best of our knowledge, a case of pseudo-rhabdomyomatous mesenchymal hamartoma has not been reported to date.

Two new cases of aquagenic wrinkling of the palms and literature review on drug interactions

Aquagenic wrinkling of the palms (AWP) is a rare, acquired condition of the skin, defined by transient rapidly developing white to translucent papules on palms and/or soles after brief exposure to water. Aquagenic wrinkling of the palms is associated with cystic fibrosis (CF). Therefore, the diagnosis of AWP can be important. Etiopathogenesis of AWP is still unclear. Treatment is often unsatisfactory and can be very challenging. This article contributes to the knowledge of AWP as we describe two new cases of aquagenic wrinkling of the palms: one patient with familial history of CF and one patient with AWP that was presumed to be induced by use of non-steroidal anti-inflammatory drugs. In addition, we present a review of the literature on drug-induced AWP.

Photo Vignette

Angiokeratoma circumscriptum

Angiokeratoma circumscriptum is the rarest variant of angiokeratoma. It usually affects females and it is characterized by dark-red to blue-black confluent papules or nodules on lower limbs in a segmental and unilateral distribution. We describe the clinical and histopathological findings in a patient with angiokeratoma circumscriptum and discuss the etiology, associations, diagnosis, differential diagnosis, and treatment.

Rare presentation of adult-onset cutaneous mastocytoma of the breast

Mastocytosis is a rare condition in which mast cells accumulate throughout various organs of the body-the most common subtype being confined to the skin. We present an unusual case of cutaneous mastocytosis localized to the unilateral breast of a young woman with partial involvement of the areola. Previously diagnosed as nipple eczema, the patient failed appropriate treatment with class III and IV topical corticosteroids. Given it was adult onset, failed appropriate treatment, and had an atypical clinical appearance, a biopsy was pursued that revealed mastocytosis in skin. This is another clinical diagnosis dermatologists may consider in their differential diagnosis of nipple dermatitis.

Subcutaneous fat necrosis of the newborn: clinical and histopathological review and use of cutaneous ultrasound Necrosis grasa subcutánea del recién nacido: revisión clínica e histopatológica y utilidad de la ecografía cutánea

Subcutaneous fat necrosis of the newborn is a rare lobular panniculitis. It is characteristic of term or post-term neonates with a history of perinatal compromise or maternal gestational pathology. The cutaneous manifestations consist of erythematous and indurated subcutaneous plaques and nodules located over the dorsal region and the shoulders. Diagnosis is clinical and pathological. Histopathological findings include lobular panniculitis with a lymphohistiocytic inflammatory infiltrate with few neutrophils, fatty necrosis, deposition of radial needle-shaped crystals in the adipocytes, and possible calcification and hemorrhage. The cutaneous ultrasound shows hyperechoic and avascular subcutaneous cellular tissue and acoustic shadows may appear corresponding to calcifications. The clinical differential diagnosis includes sclerema neonatorum and post-corticosteroid panniculitis. Histologically crystal-forming panniculitis conditions are in the differential diagnosis. The disease is usually self-limited but complications such as hypercalcemia, hypoglycemia, hypertriglyceridemia, thrombocytopenia, and anemia may occur. Complications should be ruled out and treated at diagnosis and during follow-up. The most important complication is hypercalcemia.

La necrosis grasa subcutánea neonatal es una paniculitis lobulillar infrecuente. Es característica de neonatos a término o postérmino con antecedentes de sufrimiento perinatal o patología gestacional materna. Las manifestaciones cutáneas consisten en placas y nódulos subcutáneos eritematosos e indurados localizados preferentemente en la región dorsal y los hombros. El diagnóstico es clínicopatológico. Los hallazgos histopatológicos comprenden una paniculitis lobulillar con un infiltrado inflamatorio linfohistiocitario con escasos neutrófilos, necrosis grasa, depósito de cristales radiados en los adipocitos y posibles focos de calcificación y hemorragia. En la ecografía cutánea se observa hiperecogenicidad y avascularización del tejido celular subcutáneo y pueden aparecer sombras acústicas posteriores que se correspondencon calcificaciones. El diagnóstico diferencial clínico se debe realizar con el escleredema neonatorum y la paniculitis postesteroidea, e histológicamente con las paniculitis con formación de cristales. La enfermedad suele ser autolimitada pero pueden aparecer complicaciones como la hipercalcemia, la hipoglucemia, la hipertrigliceridemia, latrombocitopenia y la anemia. Las complicaciones deben ser descartadas y tratadas en el diagnóstico y durante el seguimiento. La complicación másimportante es la hipercalcemia.