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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 5, 2020


Review of the use of gentian violet in dermatology practice

Objective: To review the use of gentian violet in dermatology. Design: A comprehensive literature search on gentian violet in dermatology practice was performed through PubMed. Results: Gentian violet is effective in treating methicillin-resistant Staphylococcus aureus-colonized skin lesions; mean number of days for complete eradication was 9.1 days. Gentian violet is almost as effective as ketoconazole and more effective than nystatin in the treatment of oral thrush in AIDS patients. In an in vitro study on cutaneous T cell lymphoma cell lines, there was no difference between nitrogen mustard and gentian violet in stimulating apoptosis. When comparing gentian violet to silver sulfadiazine dressings in healing burn wounds, the gentian violet treatment group reported less pain, fewer febrile episodes, and decreased bacterial growth compared to control. In atopic dermatitis subjects, gentian violet decreased Staphylococcus aureus colonization and improved disease severity in lesional skin compared to non-lesional skin. Conclusion: Studies have investigated gentian violet's antibacterial, antifungal, antiviral, antiparasitic, anti-angiogenic, antitumor, and wound healing properties. Gentian violet is a low cost and well-tolerated topical agent with the potential for widespread applications in dermatology.


Patients use more topical medication when the medications come in a larger container

Introduction: Research shows that individuals consume more calories when provided with a larger portion size. It is unclear if similar behavior translates to topical medication use. The impact of container size and provider instructions on patient usage of topical medications has yet to be assessed. Methods: Data was collected from 128 participants in an IRB randomized, controlled trial. To a marked 3cmx8cm rectangle on the forearm, patients applied petroleum jelly from either a large container or a small tube. Pre and post application container weights were measured. Results: Patients applied more topical medication from the large container compared to the small tube. Conclusion: Topical medication usage is influenced by the size of the container provided. It is beneficial to consider container size when prescribing topical medications and greater application is desired.

Case Presentation

Resolution of pembrolizumab-associated lichenoid dermatitis with a single dose of methotrexate

We present a 53-year-old woman with severe lichenoid dermatitis secondary to pembrolizumab therapy that was refractory to both topical and oral steroids. After almost three months without improvement, the rash was effectively combated with a single 15mg dose of methotrexate. We hope this case will help guide the management of the cutaneous adverse effects of anti-PD1 immunotherapy.

Linear lesions on the arm of a child: a diagnostic challenge

There are a number of conditions that follow the lines of Blaschko. Linear discoid lupus erythematosus is a rare variant of chronic lupus erythematosus with less than 20 cases reported in children. It can be misdiagnosed as lichen striatus or linear morphea. We describe a 15-year-old boy with a confirmed histologic diagnosis of linear chronic discoid lupus erythematosus following the lines of Blaschko, with no signs of systemic involvement.

Pseudorheumatoid nodule: a variant of granuloma annulare?

We present an adult woman with subcutaneous nodules without any signs or symptoms of rheumatoid arthritis. These nodules are believed to be pseudorheumatoid nodules, which are considered a deep form of granuloma annulare. This case is unique because these are typically found in children and have rarely been reported in adults. These nodules are typically asymptomatic and do not require treatment. However, attempts have been made to treat them with intralesional corticosteroids, cryotherapy, or excision. Owing to the fact that this is considered a deep form of granuloma annulare, they are sometimes treated similarly with a combination of monthly rifampin, ofloxacin, and minocycline.

Signet-ring squamous cell carcinoma: a report of a rare variant and review of the literature

Signet-ring squamous cell carcinoma is a rare histological subtype of squamous cell carcinoma. The distinct morphologic appearance of this variant can mimic metastatic adenocarcinoma and impose a diagnostic challenge. Unlike its glandular counterpart, signet-ring cell variant of squamous cell carcinoma has a poorly characterized histopathogenesis with no known prognostic implication. We describe an additional case and review the literature.

Granulomatous pyoderma gangrenosum in a patient with ulcerative colitis

A 34-year-old woman with a past history of inflammatory bowel disease developed a painful elevated edematous swelling with ulcerations on the dorsum of her left foot. Histopathological examination revealed dense infiltration of neutrophils and mononuclear cells in the lower dermis and subcutaneous tissue. Tumor necrosis factor (TNF) was strongly detected in giant cells. To date, only a few cases of pyoderma gangrenosum with granulomatous changes have been reported. Tumor necrosis factor may have played a role in the granulomatous reaction in our case.

Pyodermatitis-pyostomatitis vegetans: a case report and review of literature

Pyodermatitis-pyostomatitis vegetans is a rare inflammatory dermatosis. There is a strong association between pyodermatitis-pyostomatitis vegetans and inflammatory bowel disease, particularly ulcerative colitis. Herein, we report a case of pyodermatitis-pyostomatitis vegetans with positive direct immunofluorescence staining findings and review the literature for the past 18 years to characterize the disease, its epidemiologic characteristics, its associations, and the pathology and direct and indirect immunofluorescence findings. The total number of cases was 38, including 22 men and 16 women, with an average age of forty. Direct immunofluorescence staining had been performed for 32 patients, of which 12 had positive findings. Of those with positive direct immunofluorescence, 6 patients showed IgA cell surface staining. A recent approach suggests that these immunological findings may not be accidental and indicates a possible overlap with autoimmune bullous diseases discussed in this review.

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Lipedematous scalp. A rare entity in the pediatric ageLipedema de cuero cabelludo: una entidad infrecuente en pediatría.

Lipedematous scalp is an uncommon entity of unknown etiology, rarely described in the pediatric age. It is characterized by boggy thickening of the scalp predominantly located at the vertex and occiput, which acquires a cotton-like consistency. This condition is palpable rather than visible. It is a casual finding because it is usually asymptomatic, although it may involve alopecia, pruritus, or dysesthesia. We report a 10-year-old girl with lipedematous scalp without alopecia. Sonographic and MRI findings confirmed the diagnosis of lipidematous scalp. 

El lipedema de cuero cabelludo o cuero cabelludo lipedematoso es una entidad infrecuente y de etiología desconocida, rara vez descrita en la edad pediátrica. Se caracteriza por un engrosamiento difuso y de tacto esponjoso del tejido celular subcutáneo localizado principalmente en vértex y occipucio. Suele ser un hallazgo casual dado que habitualmente cursa de forma asintomática, aunque puede asociar alopecia, prurito o disestesias. Presentamos el caso de una niña de 10 años de edad con lipedema de cuero cabelludo sin alopecia asociada. Los hallazgos ecográficos y de resonancia magnética confirmaron el diagnóstico de lipedema de cuero cabelludo.

Pseudolymphomatous folliculitis

Pseudolymphomatous folliculitis is a benign entity that is included within pseudolymphomas. Because of its rapid clinical growth and suspicious histology it has to be differentiated from malignant entities. Given its low frequency, the dermatoscopic characteristics of this entity are not well-characterized and have been described only once previously. We present a middle-aged woman with a facial erythematous plaque of 6 months' evolution, with dermatoscopy in which follicular plugs on an erythematous base were appreciated. The histology showed a dense lymphocytic infiltrate with folliculotropism and follicular alteration, with numerous peripheral histiocytes positive for S100 and CD1a. The lesion partially disappeared after the biopsy, and completely after topical treatment.

Asymmetric periflexural exanthem of childhood and influenza virus infection.

Asymmetric periflexural exanthem of childhood (APEC) is a self-limited disease characterized by unilateral exanthem. The etiology is unknown, but a viral agent is suspected. Most often there is no formal proof of an associated viral etiology, but several associations between APEC and some viruses have been described. We report a 2-year-old girl with APEC associated with influenza A. This case allows us to provide an additional argument on a probable viral etiology of APEC and a possible etiologic role of influenza A.

Painful nodule on a young woman's cheek

We present a 30-year-old woman with a solitary circumscribed neuroma (also known as palisaded encapsulated neuroma) diagnosed after surgical excision. We describe the histopathologic correlation and the dermoscopic features we found in this tumor, which have not been previously reported in the literature to our knowledge.

Amelanotic melanoma in a patient with oculocutaneous albinism

Oculocutaneous albinism is a genetically heterogeneous, autosomal recessive group of disorders characterized by a generalized decreased or absence of melanin pigment in the eyes, hair, and skin. These patients have a greater sensitivity to UV radiation and a predisposition to skin tumors, mainly squamous cell carcinoma and basal cell carcinomas, and to a lesser extent malignant melanomas. Melanoma can be one of the most challenging cancers to diagnose in patients with albinism. We report an uncommon clinical presentation of melanoma, an amelanotic melanoma in the right supraciliar region in a patient with oculocutaneous albinism. The clinical presentation was an erythematous, scaly and ill-defined plaque. The skin biopsy revealed a lentigo maligna melanoma. Amelanotic melanomas are one of the two most difficult to diagnose subtypes of melanoma, together with the nevoid type. Melanoma in oculocutaneous albinism patients are often amelanotic, which makes their clinical diagnosis very difficult. These patients should be examined in the dermatology department at least once a year and it is recommended to have a high index of suspicion.

SAPHO syndrome: the value of classic drugs in the era of biologics

SAPHO syndrome is a rare entity, composed of dermatologic and osteoarticular manifestations. There are no validated diagnostic criteria and treatment is empirical, with a recent focus on biologics. Herein, we present a 50-year-old woman who developed palmoplantar pustulosis and sternoclavicular osteitis, with typical findings on bone scintigraphy. Treatment with bisphosphonate, low-dose systemic corticosteroid, and cyclosporine allowed complete resolution of the articular and dermatologic manifestations with no side effects.

Dermoscopic patterns of terra firma-forme dermatosis

Terra firma-forme dermatosis is a relatively common but probably underestimated entity characterized by asymptomatic cutaneous pigmentation resembling dirty skin. Dermoscopy is a non-invasive diagnostic tool used in the diagnosis of many cutaneous conditions. In this study we aimed to reveal dermoscopic patterns of the entity. A total of 10 patients diagnosed with terra firma-forme dermatosis were enrolled. The most common dermoscopic pattern was polygonal brown clods arranged in a mosaic pattern (N=7). The other patterns observed were seborrheic keratosis-like pattern (N=2) and perifollicular hyperpigmentation (N=1). Rubbing with 70% ethyl alcohol resulted in complete resolution of the lesions in all patients.


Cutaneous undifferentiated pleomorphic sarcoma is a pleomorphic dermal sarcoma

Pleomorphic dermal sarcoma is a cutaneous soft tissue sarcoma that presents as a rapidly enlarging tumor, typically on a sun-exposed location of elderly individuals. The neoplasm shares many similar features — clinical, pathologic, immunohistochemical and genomic — with atypical fibroxanthoma. However, adverse histologic characteristics (deep subcutaneous invasion, tumor necrosis, lymphovascular invasion, and/or perineural invasion) differentiate pleomorphic dermal sarcoma from atypical fibroxanthoma and may account for the more aggressive biologic behavior of pleomorphic dermal sarcoma: local recurrence and metastases. The features of a woman with pleomorphic dermal sarcoma are described. Her sarcoma presented as a rapidly growing ulcerated red nodule on the left side of her face. Imaging studies were performed prior to surgery. The tumor was extirpated with a wide local excision and she received postoperative radiotherapy. There has been no recurrence or metastasis at one-year follow-up. Pleomorphic dermal sarcoma has previously been referred to as a malignant fibrous histiocytoma (until the term became antiquated) and an undifferentiated pleomorphic sarcoma. However, the latter term includes not only neoplasms from the skin but also sarcomas from internal organs, retroperitoneal and osteoid origin. Therefore, when classifying this undifferentiated soft tissue sarcomas of cutaneous origin, the term pleomorphic dermal sarcoma may be preferred.

Use of an adherent fenestrated drape to anchor an adjacent vertical sterile surgical towel

Vertical surgical sites or those on reclining patients often present a challenge when establishing and securing a sterile field. The drape or towel most proximal to the physician is often vertically oriented. The forces of gravity and movements of surgery can shift or detach this vertical drape. Sterile clamps are not always available or are needed for securing other instruments. We present a method to secure this vulnerable drape using a central fenestrated adherent drape.

The dilemma of treating pyoderma gangrenosum associated with monoclonal gammopathy of undetermined significance

Pyoderma gangrenosum (PG) is a rare ulcerative skin condition. It can be associated with a number of systemic diseases. Association with monoclonal gammopathy of undetermined significance (MGUS) is uncommon, but prognosis may be different depending upon the type of MGUS. Cases of MGUS- related PG reported in the literature with data concerning evolution and treatment were identified through a PubMed search. A patient with recurrent PG in the setting of a MGUS-IgA-? in our department was also included. In total, 10 cases were identified. Only the two cases with Ig populations other than IgA improved without recurrence after treatment of the PG. All the patients with MGUS-IgA showed recurrences. Early multiple myeloma was proposed for three patients with MGUS-IgA-related PG. Second or third line treatments were necessary in some cases.

Exogenous acral pigmentation induced by coleoptera: an underdiagnosed mimic of severe disease.

Acral purpura is generally a hallmark for severe internal disease. However, exogenous pigmentation related to contact with invertebrates, can induce acral purpura-like lesions. Data regarding the beetle's ability to cause skin hyperpigmentation or purpura-like lesions are scarce. We report a case of exogenous pigmentation caused by accidental contact with a darkling beetle, clinically simulating acral purpuric lesions. The history of recent drug inhalation and abnormal autoimmunity tests made this diagnosis difficult.