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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 28, Issue 5, 2022


Efficacy of gabapentinoids for acute herpes zoster in preventing postherpetic neuralgia: a systematic review of randomized controlled trials

Gabapentinoids (e.g., gabapentin and pregabalin) have been established as a treatment for postherpetic neuralgia (PHN), but their effects on the prevention of PHN are unclear. This systematic review aimed to evaluate the efficacy of gabapentinoids for acute herpes zoster (HZ) in preventing PHN. PubMed, EMBASE, CENTRAL, and Web of Science were queried December 2020 to collect data on relevant randomized controlled trials (RCTs). A total of four RCTs (including 265 subjects) were retrieved. Overall, the incidence of PHN was lower, but not statistically significant in the gabapentinoid-treated group compared to the control group. Subjects treated with gabapentinoids were more likely to experience adverse events such as dizziness, somnolence, and gastrointestinal symptoms. This systematic review of RCTs showed that the addition of gabapentinoids during acute HZ are not significantly effective in preventing PHN. Nevertheless, the evidence on this subject remains limited. Physicians should carefully weigh the risks and benefits of prescribing gabapentinoids during the acute phase of HZ owing to its side effects.

The use of oral vitamin A in acne management: a review

Background: Changes to the iPLEDGE platform on December 13, 2021 made isotretinoin virtually inaccessible for many patients. Prior to the FDA approval of isotretinoin, a derivative of vitamin A, in 1982, vitamin A was used for severe acne. Objective: To review the efficacy, safety, affordability, and practicality of vitamin A as a substitute for isotretinoin when the latter is inaccessible. Methods: A literature review of PubMed was conducted using the key words: oral vitamin A, retinol, isotretinoin, Accutane, acne, iPLEDGE, hypervitaminosis A, and side effects. Results: We identified 9 studies (8 clinical trials and one case report); acne improved in 8 studies. Dosages ranged from 36,000IU daily to 500,000IU with 100,000IU as the most common. Mean duration until clinical improvement was 7 weeks to four months after initiation of therapy. Mucocutaneous side effects were most common, along with headaches, which resolved with either continued treatment or cessation. Conclusion: Oral vitamin A is efficacious for the treatment of acne vulgaris, although the available studies have limited controls and outcomes. Side effects are qualitatively similar to those of isotretinoin and avoiding pregnancy for at least three months after stopping treatment is critical; like isotretinoin, vitamin A is a teratogen.


Whole exome sequencing in a sample of Peruvian patients diagnosed with epidermolysis bullosa

Background: Epidermolysis bullosa (EB) is a complex and heterogeneous dermatological disease. Four main types of EB have been described, each of them with distinct characteristics: EB simplex (EBS), dystrophic EB (DEB), junctional EB (JEB) and Kindler EB (KEB). Each main type varies in its manifestations, severity, and genetic abnormality. Methods: We sought mutations in 19 genes known to cause EB and 10 genes associated with other dermatologic diseases in 35 Peruvian pediatric patients of a rich Amerindian genetic background. Whole exome sequencing and bioinformatics analysis was performed. Results: Thirty-four of 35 families revealed an EB mutation. Dystrophic EB was the most frequently diagnosed type, with 19 (56%) patients, followed by EBS (35%), JEB (6%), and KEB (3%). We found 37 mutations in seven genes; 27 (73%) were missense mutations; 22 (59%) were novel mutations. Five cases changed their initial diagnosis of EBS. Four were reclassified as DEB and one as JEB. Inspection into other non-EB genes revealed a variant, c.7130C>A, in the gene FLGR2, which was present in 31 of the 34 patients (91%). Conclusion: We were able to confirm and identify pathological mutations in 34 of 35 patients.

Dermatology urgent care model reduces costs and healthcare utilization for psychodermatology patients - a retrospective chart review

Background: Patients with psychiatric dermatoses may be high users of healthcare, especially emergency services. A dermatology urgent care model may reduce healthcare utilization in this population. Objective: To determine whether a dermatology urgent care model can reduce healthcare utilization among patients with psychiatric dermatoses. Methods: We conducted a retrospective chart review of patients seen in dermatology urgent care at Oregon Health and Science University between 2018 and 2020 with diagnoses of Morgellons disease and neurotic excoriations. Rates of diagnosis-related healthcare visits and emergency department visits were annualized before and during engagement with the dermatology department. Rates were compared using paired t-tests. Results: We found an 88.0% reduction in annual rates of healthcare visits (P<0.001) and 77.0% reduction in emergency room visits (P<0.003). Results were unchanged when controlled for gender identity, diagnosis, and substance use. Limitations: We could not account for healthcare use not included in electronic health record. Conclusion: Urgent care models in dermatology may reduce overuse of healthcare and emergency services among patients with psychiatric dermatoses.

Limited impact of teledermoscopy on referrals to face-to-face dermatology

Background: Teledermoscopy improves teledermatology clinical outcomes, but the practical impact of this and other teleconsultation variables on patient management are unclear. We assessed the impact of these variables, including dermoscopy, on face-to-face (F2F) referrals to optimize effort by imagers and dermatologists. Methods: Using retrospective chart review, we retrieved demographic, consultation, and outcome variables from 377 interfacility teleconsultations sent to San Francisco Veterans Affairs Health Care System (SFVAHCS) between September 2018 to March 2019 from another VA facility and its satellite clinics. Data were analyzed using descriptive statistics and logistic regression models. Results: Of 377 consults, 20 were excluded due to patient F2F self-referral without teledermatologist recommendation. Analysis of consults showed that age, clinical image, and problem number but not dermoscopy were associated with F2F referral. Analysis of problems contained in consults showed that lesion location and diagnostic category were also associated with F2F referral. Skin cancer history and problems on the head/neck were independently associated with skin growths in multivariate regression. Conclusions: Teledermoscopy was associated with variables related to neoplasms but did not affect F2F referral rates. Rather than utilize teledermoscopy for all cases, our data suggests that referring sites prioritize teledermoscopy for consultations with variables associated with a likelihood of malignancy.


Herpes manuum: a new name for non-digit herpetic whitlow

Herpes simplex virus (HSV) is one of the most prevalent infections worldwide. It consists of two types: HSV1 and HSV2 that primarily cause orofacial and genital disease. However, both types can infect any site. Rarely, HSV infection of the hand occurs and is often documented as herpetic whitlow. Herpetic whitlow is primarily recognized as an HSV infection of the digits and thus HSV infection of the hand is largely associated with infection of the fingers. This is problematic, as HSV is often left off the differential diagnosis of non-digit hand pathology. We present two cases of non-digit HSV infection of the hand that were misdiagnosed as bacterial infections. As our cases and others demonstrate, the lack of knowledge that HSV infections can occur on the hand leads to confusion and delayed diagnosis among a myriad of providers. Therefore, we seek to introduce the term "herpes manuum" to increase awareness that HSV can appear on the hand in locations aside from the digits and thus differentiate it from herpetic whitlow. By doing so, we hope to encourage more timely diagnosis of HSV hand infections to decrease associated morbidity.

Case Report

Epidermolytic ichthyosis complicated by staphylococcal scalded skin syndrome in the newborn

Epidermolytic ichthyosis is characterized by erythema and blistering at birth. We present a neonate with epidermolytic ichthyosis who had a subtle change in clinical findings while hospitalized, including increased fussiness, erythema, and a change in her skin odor, which represented superimposed staphylococcal scalded skin syndrome. This case highlights the unique challenge of recognizing cutaneous infections in neonates with blistering skin disorders and emphasizes the importance of having a high suspicion for superinfection in this population.

Multiple skin neoplasms at one site (MUSK IN A NEST): collision tumor consisting of epidermal (macular seborrheic keratosis) and dermal (lichen amyloidosis) components

A collision tumor is a neoplastic lesion comprised of two or more tumors consisting of distinct cell populations in the concurrent location. Multiple skin neoplasms at one site (MUSK IN A NEST) is a term recently coined to describe two or more cutaneous benign or malignant tumors occurring at the same anatomic site. In retrospective studies, seborrheic keratosis and cutaneous amyloidosis have both individually been documented as a component of a MUSK IN A NEST. This report describes a 42-year-old woman who presented with a pruritic skin condition on her arms and legs of 13 years' duration. Skin biopsy results showed epidermal hyperplasia with hyperkeratosis, hyperpigmentation of the basal layer with mild acanthosis, and evidence of amyloid deposition in the papillary dermis. Based on the clinical presentation and pathology findings, a concurrent diagnosis of macular seborrheic keratosis and lichen amyloidosis was established. A MUSK IN A NEST consisting of a macular seborrheic keratosis and lichen amyloidosis is likely a more common occurrence than implied by the paucity of published cases of this phenomenon.

Case Presentation

Cutaneous leukocytoclastic vasculitis after second dose of mRNA COVID-19 vaccine

Numerous cutaneous reactions following COVID-19 vaccination have already been described. Vasculitis, however, is a rare adverse event, occurring mainly after the first COVID-19 vaccination. Herein, we report a patient with IgA-positive cutaneous leukocytoclastic vasculitis, unresponsive to a moderate dose of systemic corticosteroid that erupted after the second dose of the Pfizer/BioNTech vaccine. Since booster vaccinations are being administered, we intend to raise awareness among clinicians and to highlight this potential reaction and its therapeutic approach.

Questions raised by a case of adult-onset linear nodular scleroderma

Morphea presenting clinically with nodular or keloidal skin changes is extremely rare. Nodular scleroderma or keloidal morphea presenting in a linear distribution is even more uncommon. We present an otherwise healthy young woman with unilateral, linear, nodular scleroderma and review the somewhat confounding earlier literature in this area. To date, this young woman's skin changes have proven refractory to oral hydroxychloroquine and ultraviolet A1 phototherapy. Several aspects of this case including the patient's family history of Raynaud disease, her nodular sclerodermatous skin lesions, and the presence of U1RNP autoantibodies raised concern about her management with respect to future risk of developing systemic sclerosis.

Leukocytoclastic vasculitis with features of flagellate purpura: a comparison with flagellate erythema

Leukocytoclastic vasculitis is a histopathologic term describing a type of small-vessel vasculitis characterized by a predominantly neutrophilic inflammatory infiltrate and nuclear debris. Skin involvement is common and can have a heterogeneous clinical presentation. Herein, we describe a 76-year-old woman with no history of chemotherapy or recent mushroom ingestion that presented with focal areas of flagellate purpura secondary to bacteremia. Histopathology revealed leukocytoclastic vasculitis and her rash resolved after antibiotic treatment. It is important to distinguish flagellate purpura from a similar condition, flagellate erythema, as they have been reported in association with distinct etiological and histopathological features.

Treating linear porokeratosis with topical lovastatin/cholesterol cream

Linear porokeratosis is a rare variant of porokeratosis that is characterized by unilateral lesions along the lines of Blaschko. Like all variants of porokeratosis, linear porokeratosis is characterized by the histopathologic finding of cornoid lamellae bracketing the lesion. The underlying pathophysiology involves a two-hit post-zygotic knockdown of genes involved in mevalonate biosynthesis in embryonic keratinocytes. Although there is currently no standard or effective treatment, therapies targeted to rescue this pathway and restore keratinocyte cholesterol availability are promising. Presented here is a patient with a rare, extensive case of linear porokeratosis treated with compounded 2% lovastatin/2% cholesterol cream leading to partial resolution of the plaques.

Telangiectasias of the breasts showing diffuse dermal angiomatosis in a patient with diffuse livedo reticularis

The breasts are a common location for diffuse dermal angiomatosis (DDA) in a context of obesity and macromastia. The typical clinical presentation includes erythematous or purplish plaques, reticulated telangiectasias, and sometimes livedo reticularis, often complicated by painful ulcerations of the breasts. Biopsy usually confirms a dermal proliferation of endothelial cells staining positively for CD31, CD34 and SMAa and negatively for HHV8. We report herein a woman with DDA of the breasts presenting as diffuse livedo reticularis and acrocyanosis, both long-standing and considered idiopathic following extensive investigations. Since a biopsy of the livedo did not document DDA features in our case, we suggest that our patient's livedo reticularis and telangiectasias could constitute a vascular predisposition for DDA, as its pathogenesis frequently involves an underlying disease involving ischemia, hypoxia, or hypercoagulability.

Photo Vignette

Small lymphocytic lymphoma presenting as chronic diffuse lip swelling

Although rare, small lymphocytic lymphoma can present as chronic lip swelling and papules, thus mimicking the features of orofacial granulomatosis, a chronic inflammatory disorder characterized by subepithelial noncaseating granulomas, or papular mucinosis, characterized by localized dermal mucin deposition of mucin. When assessing lip swelling, one must carefully consider the clinical clues and have a low threshold to perform a diagnostic tissue biopsy, preventing delays in treatment or progression of the lymphoma.

Linear IgA bullous dermatosis of childhood

A 4-year-old boy presented with blistering on his face and distal upper and lower extremities. Subepidermal blisters containing neutrophils and eosinophils visualized on histology supported the diagnosis of linear IgA bullous dermatosis of childhood (LABDC). The dermatosis presents with vesicles and tense blisters in an annular distribution, erythematous papules, and/or excoriated plaques. Histopathology shows subepidermal blisters with a neutrophilic infiltrate in the dermis, mainly concentrated at the tips of dermal papillae in the early stage of the disease, which can be mistaken for the pattern of neutrophilic infiltration as seen in dermatitis herpetiformis. Dapsone is the treatment of choice, which is started at a dosage of 0.5mg/kg/day. Linear IgA bullous dermatosis of childhood is a rare autoimmune disease that can be mistaken for other conditions with similar presentations but should always be considered in the differential diagnosis of children with blistering.

A rare case of lues maligna in an HIV-negative woman

We describe an HIV-negative 43-year-old woman presenting with a diffuse ulceronodular eruption and positive serological tests for syphilis consistent with lues maligna. Lues maligna is a severe and rare variant of secondary syphilis characterized by prodromal constitutional symptoms followed by the formation of multiple well-circumscribed nodules with ulceration and crust. This case depicts a particularly rare presentation as lues maligna usually involves HIV-positive men. The clinical presentation of lues maligna can pose a diagnostic challenge, with infections, sarcoidosis, and cutaneous lymphoma as just a few entities in its broad differential diagnosis. However, with a high index of suspicion, clinicians can diagnose and treat this entity earlier and reduce morbidity.