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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 27, Issue 12, 2021


The effect of the COVID-19 pandemic on perceptions of teledermatology

There is limited information of the effect of the COVID-19 pandemic on the general population's perceptions towards teledermatology. This study aims to assess the pandemic's impact on people's willingness to use teledermatology as well as to investigate influencing factors. We recruited 544 participants through Amazon Mechanical Turk (MTurk) and surveyed them using REDCap. Participants' willingness to use teledermatology before, during, and after the COVID-19 pandemic was measured via a 5-point Likert scale. The survey also included questions regarding factors influencing participants' attitudes towards teledermatology and their sociodemographic characteristics. Of the 185 participants who reported unwillingness to use teledermatology prior to the COVID-19 pandemic, 79.2% and 66.5% became either neutral or willing to use teledermatology during and after the pandemic, respectively. Less than half of prior satisfactory telemedicine users reported willingness to use teledermatology before the pandemic; willingness to use teledermatology increased to 80.1% and 63.8% during and after the COVID-19 pandemic, respectively. The top reason for lack of interest in teledermatology was concern for security and privacy (24.4%). Although a useful tool, teledermatology has been met with reluctance by the public. However, the unique circumstances of the COVID-19 pandemic have improved the public's perceptions and readiness to use teledermatology.


Dermatology residency preparation curriculum: a model for initiating new residents into dermatology clinical care

Entering dermatology residency is an immersive experience requiring new specialty-specific skills. There is no standard Accreditation Council for Graduate Medical Education (ACGME) protocol for orienting new dermatology residents. We aimed to design, develop, and evaluate a curriculum for incoming first-year dermatology residents focusing on practical introduction to dermatologic clinical care emphasizing ACGME dermatology milestones. A concentrated 8-hour residency preparation course for first-year dermatology residents was designed and developed by faculty. The course encompassed clinical competencies, procedural techniques, and professionalism and collegiality principles. Teaching methods included lectures, video demonstrations, simulated patient experiences, and one-on-one practical instruction. Surveys were distributed before, immediately after, and 6-months following the course from 2016-2018 to assess participants’ skill-based confidence level and perceived usefulness of the course. A total of 24 first-year dermatology residents participated in the residency preparation course over 3 years from 2016-2018. Residents’ confidence levels in performing dermatology-specific skills immediately increased following the course and continued to increase 6 months into training. The majority of first-year residents “agreed” or “strongly agreed” that the course was helpful for improving clinical competence. Our residency preparation course increased first-year residents’ confidence and perceived competence in performing clinical skills related to ACGME dermatology milestones.

Case Report

Primary cutaneous diffuse large B-Cell lymphoma, leg type mimicking subcutaneous panniculitis-like T-cell lymphoma in a COVID-19 setting: case report and review of literature

Primary cutaneous diffuse large B-cell lymphoma, leg type is a rare entity accounting for 4% of all primary cutaneous lymphomas whose clinical presentation encompasses a range of possibilities. COVID-19 has caused a delay in diagnosis of malignant neoplasms and consequently, this has resulted in poorer prognoses. A 62-year-old woman presented with two smooth-surfaced, mobile, well-circumscribed, oval, skin-colored nodules approximately one-cm in diameter with nonerythematous borders on the lower third of the left leg. Two months later, eleven nodules measuring between one and 1.5cm with erythematous halo, slight scaling, central erosion, and crusting had appeared. Histological study showed moderate pericapillary lymphocytic infiltration in the papillary and reticular dermis and prominent diffuse proliferation of medium to large cells in the subcutis. These exhibited irregular vesicular nuclei, a conspicuous solitary nucleolus of two to three small nucleoli, and three mitoses per high power field. Adipocytes were consistently encircled by neoplastic lymphocytes. Primary cutaneous diffuse large B-cell lymphoma, leg type is a high-grade lymphoma that can manifest as a diagnostic challenge and requires adequate immunohistochemistry and in situ hybridization studies for proper diagnosis, treatment, and prognosis.

Extranodal NK/T-cell lymphoma primarily presenting as two adjacent slowly growing skin nodules with prominent epidermotropism and CD30 expression, a case report and review of literature

Extranodal NK/T-cell lymphoma (NKTCL) is a rarely occurring non-Hodgkin lymphoma with predilection for the nasal cavity. Cutaneous involvement, rarely occurring and often aggressive in behavior, may present as nodular mass-forming lesions with or without ulceration. Histologically, lesions are characterized by an atypical dermal lymphoid infiltrate with angioinvasion and associated necrosis. Fortuitously, Epstein-Barr virus (EBV) infection, implicated in the pathogenesis of this entity, serves as a useful diagnostic marker (i.e. EBER in situ hybridization). We present a 54-year-old-man who initially presented with two ulcerations on the right lower leg which progressed despite antibiotic therapy. Histologic examination demonstrated dense lymphoid infiltrates exhibiting epidermotropism, angiocentricity and angioinvasion extending into the deep dermis. Immunohistochemical staining demonstrated expression of CD2, CD3, CD8, TIA-1, perforin, and granzyme-B, consistent with a cytotoxic T-cell phenotype. Additionally, CD56 was positive, confirming the presence of a coexistent NK cell phenotype. Testing also demonstrated significant CD30 expression, and molecular analysis was positive for TCR gene rearrangement. These findings, in conjunction with EBER in situ hybridization positivity, confirmed a diagnosis of extranodal NKTCL. We aim to increase awareness of this rarely occurring lymphoma with cutaneous involvement. CD30 expression in NKTCL raises the possibility of targeted treatment with brentuximab.

Cutaneous dystrophic calcification following high-dose radiotherapy for a liposarcoma

Cutaneous dystrophic calcification as a late change of radiation therapy is a rarely reported finding. Initially, it was almost exclusively described as occurring on the chest wall in breast cancer patients but has since been described in several other malignancies. We describe the first reported case of radiotherapy-induced calcinosis cutis occurring at the site of a previous liposarcoma. Review of the literature including risk factors, similar cases, pathophysiology, and management is also explored.

Reactive granulomatous dermatitis associated with ovarian cancer and a review of its role as a harbinger for malignancy

Reactive granulomatous dermatitis (RGD) is a rare dermatosis with a variety of cutaneous manifestations unified by a dermal granulomatous infiltrate on histology. Rheumatoid arthritis and autoimmune disease are classic associations, but an increasing number of cases have been attributed to covert malignancy. Only 41 cases of paraneoplastic RGD have been documented to our knowledge and we present an additional case that manifested eight months prior to the diagnosis of ovarian cancer and clinically mimicked morphea. Histopathologic examination identifying palisaded CD68+ cells and collagen degeneration are helpful in diagnosing this entity which may mimic a host of other cutaneous processes, including metastatic disease. Cancer-directed therapies have been successful in clearing paraneoplastic RGD with or without the addition of corticosteroids, as RGD severity may be driven by the underlying malignancy. This case highlights the importance of utilizing histopathology to confirm the diagnosis given its nonspecific clinical findings, as well as the importance of considering malignancy and metastatic disease in patients diagnosed with RGD regardless of their cancer history.

Postauricular apocrine hidrocystoma: a case and dermoscopy review

Apocrine hidrocystoma (AH) is a benign cystic proliferation of apocrine sweat glands that classically presents as a slow-growing nodule on the face, especially in the periorbital region. Histopathological evaluation is required to definitively diagnose an apocrine hidrocystoma. Previous studies have described apocrine hidrocystomas in unusual locations. However, the authors have identified only two reported cases of apocrine hidrocystoma in the postauricular region. We present a third case of a postauricular hidrocystoma in a 26-year-old woman, as well as a brief review of the dermoscopic findings of apocrine hidrocystomas in the existing literature.

Case Presentation

An uncommon case of metastatic myxofibrosarcoma presenting with elbow and hip masses

Myxofibrosarcoma frequently recurs locally but rarely metastasizes. Herein, we describe an elderly woman who had myxofibrosarcoma of the right elbow that went untreated during the COVID-19 pandemic. She subsequently presented with two large tumors ulcerating through the skin of her right elbow and left hip.

Sclerosing perineurioma: a rare benign tumor in a pediatric patient

A 15-year-old boy presented to outpatient dermatology clinic for evaluation of a lesion on the hand. Originally small and asymptomatic, the lesion had rapidly enlarged in the six months prior to evaluation. A shave biopsy was performed and histopathologic evaluation demonstrated a well-circumscribed nodular proliferation of dense, bland, epithelioid to spindle cells on a fibrillary background. Tumor cells were diffusely epithelial membrane antigen (EMA) positive; S100 and Melan-A were negative. These findings are consistent with a diagnosis of sclerosing perineurioma. This case illustrates the presentation of sclerosing perineurioma in a pediatric patient and we review the pertinent pathologic and immunohistochemical findings necessary for diagnosis. It is imperative to distinguish this entity from other soft tissue tumors on the hand, both benign and malignant, to avoid overly aggressive surgical intervention.

Photodermatitis following knee intra-articular hylan G-F 20 injection for osteoarthritis: two cases

Hyaluronic acid (HA) intra-articular injections are increasingly used for the treatment of knee osteoarthritis. Described adverse reactions of HA intra-articular injections include injection site pain or swelling. A 71-year-old man and a 65-year-old woman independently presented with photodistributed lesions shortly after receiving a repeat HA injection (hylan G-F 20) intra-articularly. A punch biopsy was performed which was consistent with a photodrug reaction or hypersensitivity reaction. Two cases are presented to describe a novel presentation of a photosensitivity reaction to HA.

Prurigo pigmentosa in a patient with newly diagnosed type one diabetes with diabetic ketoacidosis

Prurigo pigmentosa is a rare inflammatory cutaneous disorder associated with ketosis that resolves with reticulate hyperpigmentation. A 19-year-old man was admitted to the hospital with diabetic ketoacidosis. He also had developed reticulate papules coalescing into plaques over the posterior neck, back, and abdomen. Histopathological findings consistent with the clinical findings suggested the diagnosis of prurigo pigmentosa. After treatment with topical triamcinolone and oral doxycycline along with resolution of his ketosis after insulin administration, the patient's rash healed with reticulate hyperpigmentation.

An acute, ulcerative, sarcoidal tattoo reaction following SARS-CoV-2 mRNA-1273 vaccination

Two weeks after her first dose of the SARS-CoV-2 mRNA-1273 (Moderna) vaccine, a 38-year-old woman developed acute-onset pain and ulceration within a tattoo on the distal left leg. Progressive ulceration was noted approximately one week following her second dose of the vaccine. A biopsy revealed sarcoidal granulomas and a dense neutrophilic infiltrate. Ultimately, the final diagnosis of what we have termed a "sarcoidal reaction with a Sweet-like phenomenon" was made; the patient experienced a reduction in pain and re-epithelialization of the ulcers with two weeks of the use of topical clobetasol 0.05% cream twice daily.

Atypical vascular lesions extending outside the radiation field: a diagnostic challenge

Atypical vascular lesion (AVL) is an uncommon, benign vascular proliferation seen in previously irradiated skin, most commonly after radiotherapy for breast cancer. Atypical vascular lesion and angiosarcoma may share overlapping clinical and histopathologic features. We report the first case of AVL occurring outside the field of radiation. This patient's clinical course and histopathology was overall consistent with AVL, including two biopsies with focal MYC positivity. However, due to variations in the interpretation of her histopathology, the management plans devised by two centers involved in her care were widely discordant and she was treated with chemotherapy and extensive surgery for angiosarcoma. Great care must be taken to distinguish between these entities, as treatment for angiosarcoma may be associated with significant morbidity.

Erythema multiforme as a consequence of COVID-19 infection

Cutaneous manifestations of the 2019 coronavirus disease (COVID-19) are diverse and may be the only clinical evidence of infection, particularly in children [1]. The authors report a 10-year-old girl with erythematous vesicular papules and targetoid lesions of the extremities two weeks after polymerase chain reaction (PCR) confirmed severe acute respiratory syndrome coronavirus two (SARS-COV-2) infection. Biopsy depicted classic erythema multiforme (EM) and serology confirmed positive COVID-19 antibodies. This report demonstrates one of the first reported pediatric cases of typical clinical and histopathologic EM in relation to confirmed COVID-19.

Delayed-onset cutaneous eruption associated with lenalidomide in setting of multiple myeloma

Lenalidomide (LEN) is increasingly being used for the treatment of multiple myeloma (MM). Adverse cutaneous reactions to LEN are common and present almost exclusively within one month of initiating therapy. We report a case of delayed-onset LEN-associated eruption presenting over three years after starting treatment. Histopathologic findings are also described, which are infrequently reported for LEN-associated eruptions. Our case serves as a reminder that proper recognition and management of LEN-associated eruption is important in the treatment of MM. Dermatologists should be aware of the potential for delayed presentations of adverse cutaneous reactions to LEN, even years after initiation.

Laugier-Hunziker syndrome: a case and dermoscopic features

Laugier-Hunziker syndrome (LHS) is a sporadic, acquired, and infrequent condition characterized by the onset of brown macules on the lips, the oral mucosa, and the acral glabrous skin (mainly fingers and toes) in middle-aged patients. In several cases melanonychia of fingernails and toenails coexists. No other systemic involvement is observed. A case of LHS in a 50-year-old woman is described, with particular attention to dermoscopic features. No dermoscopic specific findings of mucosal/cutaneous maculae have been to date described in the literature. Accumulation of dermoscopic observations of pigmented lesions in LHS is needed and if found to be distinct, it may contribute to a more accurate diagnosis in the future

Photo Vignette

A pearly nodule on an indurated plaque

We present an 81-year-old man who presented for evaluation of an indurated plaque with an exophytic, pearly, skin-red-brown colored nodule with central ulceration on his chest that evolved over the course of several months and was initially suspected to be basal cell carcinoma. Biopsy demonstrated histological features of dermal spindle cell proliferation in a storiform fashion with CD34 positivity confirming a diagnosis of dermatofibrosarcoma protuberans (DFSP). Dermatofibrosarcoma protuberans are rare, slowly progressive soft tissue sarcomas. The rate of DFSP is greatest among African Americans (8.3/1,000,000), occurring nearly twice as frequently when compared to Caucasians. Aside from race/ethnicity, age, and skin trauma, no specific risk factors are associated with DFSP. Complete excision is curative. Given its pearly skin colored appearance, papular/nodular/atrophic morphology variants, and tendency to form indurated plaques, DFSP may be mistaken for nodular and morpheaform basal cell carcinoma subtypes, as well as a variety of other conditions. This case highlights the importance of maintaining DFSP on the differential diagnosis of slowly progressive nodules and indurated plaques, especially in African Americans.

Unilateral swelling and hyperpigmented papules

Lymphangioendothelioma, also known as acquired progressive lymphangioma, is a rare vascular neoplasm of lymphatic origin. Although in light-skinned individuals lesions typically present as erythematous to violaceous papules or plaques, in dark-skinned patients lesions often appear hyperpigmented. Histopathologic distinction of lymphangioendothelioma from early Kaposi sarcoma and angiosarcoma is imperative considering the therapeutic and prognostic implications. Herein, we present a 71-year-old woman with slowly progressive hyperpigmented papules and histopathology demonstrating thin-walled vascular spaces interspersed between collagen bundles, consistent with lymphangioendothelioma. We describe the clinical and histologic findings of this rare entity and highlight histologic mimics that might result in diagnostic delay.

Surgical Pearl

The Twizzler: a modified primary closure for distal lower extremity wound reconstruction utilizing a dynamic winch stitch

Management of lower extremity wounds following successful tumor excision presents multiple challenges. Distal lower extremity integument is highly prone to edema often lacks adequate skin laxity for standard primary closures. The closure must be resilient enough to withstand mobility. As a result, optimal reconstruction may include skin grafting, rotational flaps, free tissue transfers, healing by second intention, or some combination. These methods may involve multiple steps in reconstruction, a prolonged recovery period, increased cost, and higher infection risk. We propose a modified primary closure that takes advantage of the visco-elastic properties of the skin without introducing additional components or steps. This technique is initiated with percutaneous suture in order to intermittently stretch the skin with constant tension. This load cycling allows for lower extremity skin to stretch over time and ultimately reduce wound edge tension, allowing for ease of absorbable suture placement. The Twizzler technique is cost-effective, uses readily available supplies, and effectively closes relatively large defects on the lower extremities.

Reconstruction of cutaneous dorsal finger defects

Background: Reconstruction of surgical defects on the dorsal finger can be challenging because of a lack of adjacent tissue reservoirs, poor laxity, and often thin, atrophic skin surrounding the defect.Objective: To present reconstructive options for cutaneous dorsal finger defects.Methods: We describe our five preferred approaches to reconstructing cutaneous dorsal finger defects based on the amount of available underlying tissue and location of the defect on the finger.Results: In the authors’ opinion, for smaller defects between and including the metacarpophalangeal joint extending to the proximal interphalangeal joint, a transposition flap or unilateral advancement flap is preferable. For proximal finger defects that are wider, a unilateral rotation flap is appropriate. A Burow full-thickness skin graft can be used for any proximal defect with underlying soft tissue present. For defects with underlying bone or tendon present, a reverse cross-finger interpolation flap can be utilized.Conclusions: The unilateral advancement flap, unilateral rotation flap, transposition flap, full-thickness skin grafts, or the reverse cross-finger interpolation flap can be used to reconstruct the majority of cutaneous dorsal finger defects.

Recruitment Advertisement

Position Title: Academic Pediatric Dermatologist

Position descriptionThe University of California, Davis, School of Medicine, Department of Dermatology, is recruiting for a pediatric dermatologist in the Clinical X series or Health Sciences Clinical Professor (HSCP) series at the Assistant/Associate Professor level based on experience and qualifications. Expectations of the Clinical X series are to engage in teaching, research, service, and clinical work, while expectations of the faculty in the HSCP series are primarily clinical and include teaching, service, and scholarly and/or creative activity. The appointments may be made up to 100%.