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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 20, Issue 4, 2014


Social media impact factor: the top ten dermatology journals on facebook and twitter

Academic journals are mainly rated according to their impact factors. However, considering the enormous worldwide impact of social media, journals and potential authors may want to take social media impact into account.


Top dermatologic diagnoses by age

Background: Although some skin conditions predominate in patients of certain ages, little data exists about the relative prevalence of dermatologic conditions by age.Objectives: To determine the common skin conditions by age group in the United States, both in dermatologist samples and for all specialties.Methods: The National Ambulatory Medical Care Survey (NAMCS) was queried for top diagnoses at dermatologist and all skin disease visits from 1993-2010. ICD-9 coding was used for diagnoses.Results: There were 588 million estimated visits to dermatologists in the US from 1993-2010. Atopic dermatitis, acne, and actinic keratosis were the top diagnoses in all age groups. Common diagnoses in all groups included contact dermatitis and benign neoplasm. There were 740 million estimated skin disease visits to all physicians; more of these were acute or infectious. The percent of skin diseases seen by dermatologists gradually increased with age to a maximum of 55% in the 75-84 year age group.Conclusion: Dermatologic conditions seen in different age groups and between dermatologists and non-dermatologists vary. With advancing age, Americans increasingly seek a dermatologist rather than a non-dermatologist physician for skin conditions.


Erythema Nodosum – A Review of an Uncommon Panniculitis

Panniculitis, inflammation of the subcutaneous fat, is a relatively uncommon condition that usually presents with inflammatory nodules or plaques. Erythema nodosum (EN) is clinically the most frequent form of panniculitis and is considered a reactive process that may be triggered by a wide variety of stimuli. Whilst up to 55% of EN is considered idiopathic, the most common causes include infections, drugs, systemic illnesses such as sarcoidosis and inflammatory bowel disease, pregnancy, and malignancy. EN typically presents in the teens and 20s, and is seen more commonly in females. It is often preceded by a non-specific prodrome of one to three weeks, which may include fever, malaise, and symptoms of an upper respiratory tract infection. Cutaneous lesions then follow, typically localized on the extensor aspect of the limbs. The lesions are painful rounded or oval, slightly raised, non-ulcerative red nodules. The exact pathogenesis of EN is not understood, although is thought to result from deposition of immune complexes in the venules of the septae in subcutaneous fat, causing a neutrophilic panniculitis. The classical histopathological picture is of a septal panniculitis without vasculitis. However, the pathological features vary with the chronology of the lesions. Even without specific therapy for a causative condition, EN typically resolves without treatment. Therefore, symptomatic support is adequate for the majority of patients.

An atlas of the morphological manifestations of hidradenitis suppurativa

This article is dermatological atlas of the morphologic presentations of Hidradenitis Suppurativa (HS). It includes: superficial abscesses (boils, furnucles, carbuncles), abscesses that are subcutaneous and suprafascial, pyogenic granulomas, cysts, painful erythematous papules and plaques, folliculitis, open ulcerations, chronic sinuses, fistulas, sinus tracts, scrotal and genital lyphedema, dermal contractures, keloids (some that are still pitted with follicular ostia), scarring, skin tags, fibrosis, anal fissures, fistulas (i.e. circinate, linear, arcuate), scarring folliculitis of the buttocks (from mild to cigarette-like scarring), condyloma like lesions in intertrigous areas, fishmouth scars, acne inversa, honey-comb scarring, cribiform scarring, tombstone comedones, and morphia-like plaques. HS can co-exist with other follicular diseases such as pilonidal cysts, dissecting cellulitis, acne conglobata, pyoderma gangrenosum, and acanthosis nigricans. In sum, the variety of presentations of HS as shown by these images supports the supposition that HS is a reaction pattern.HS is a follicular based diseased and its manifestations involve a multitude of follicular pathologies [1,2]. It is also known as acne inversa (AI) because of one manifestation that involves the formation of open comedones on areas besides the face. It is as yet unclear why HS is so protean in its manifestations. HS severity is assessed using the Hurley Staging System (Table 1). It also remains unclear why hidradentitis may remain limited to Hurley Stage 1, evolve to the more confluent (Hurley Stage 2), or progress even further to the fully confluent (Hurley Stage 3).In addition, HS can be associated with other follicular based diseases such as pilonidal cysts (PCs) of the sacrum and buttocks, dissecting cellulitis (DC), and acne conglobata (AC), which usually involves the face, chest, When HS occurs with PCs, DC, and/or AC it is referred to as the follicular occlusion triad or tetrad [2]. HS can more rarely be associated with pyoderma gagrenosum (PG) or Crohn disease (CD), other inflammatory diseases of the skin that are not follicular. The reason for this is unclear [2]. What AC, DC, HS, CD, and PG share is that they occur in bacterially rich environments. HS probably occurs with acanthosis nigricans because many HS patients are obese [2]. This concurrence seems under reported.

Case Report

Amyloidosis cutis dyschromia: a rare form of primary cutaneous amyloidosis

Amyloidosis cutis dyschromia is a rare form of primary cutaneous amyloidosis.  Amyloid deposition in the skin occurs without systemic manifestations and produces hypopigmented and hyperpigmented macules. A 19-year-old woman is presented with progression of this condition over 16 years.

Case Presentation

Solitary papule over scalp

Folliculosebaceous cystic hamartoma (FSCH) is a rare cutaneous hamartoma characterized by follicular, sebaceous, and mesenchymal elements. Folliculosebaceous cystic hamartoma is probably not as rare as previously thought and its inclusion in the differential diagnosis of asymptomatic skin colored papules or nodules is warranted, especially if it is present in the head and neck region.

Acantose nigricante maligna: realato de caso

Os autores apresentam um caso de uma paciente de 44 anos , tabagista, com dermatose disseminada diagnosticada como acantose nigricante. As lesões da pele levaram ao diagnostico de metátase de carcinoma provavelmente de origem pulmonar, localizado na região laringofaringea, até então assintomatico.

Descripción de un caso de sarcoidosis liquenoide con hallazgos clínicos e histopatológicos característicos

Sarcoidosis is a multisystem inflammatory disease characterized by the formation of noncaseating granulomas in various organs and tissues. The majority of patients with systemic sarcoidosis will present with lung and lymph node involvement. In addition, 20% have skin involvement that may be the only manifestation of the disease or may be an important prognostic marker for involvement of other organs. There are multiple forms of presentation of cutaneous sarcoidosis, which may be a true challenge.We report a patient with a one month history of an eruption of skin colored papules. Some were grouped in a symmetrical distribution on the trunk, inner arms, and lumbar region. Pathologic examination revealed an infiltrate in the papillary dermis showing a band of noncaseating granulomas along with disruption of the basal lamina and lichenoid changes. The clinicopathological correlation confirmed the diagnosis of lichenoid sarcoidosis. We consider our case interesting owing to the clinical presentation and the lichenoid distribution of granulomas.

Syringocystadenocarcinoma papilliferum with locoregional metastases

Syringocystadenocarcinoma papilliferum (SCACP) is a rare malignant counterpart of syringocystadenoma papilliferum (SCAP). To date, less than 30 cases have been reported, and of those, only three had locoregional metastases [1,2]. Herein, we report a case of a 42-year-old man with a rapidly growing nodule on his right parietal scalp ultimately diagnosed as SCACP arising in association with a preexisting SCAP and nevus sebaceus. This case differs from prior reports in the tumor’s rapid growth and aggressive course with the development of locoregional metastases within 5-weeks from initial presentation.

Secondary mucinous carcinoma of the skin

We report a case of a woman who presented with a cystic-appearing nodule on her left nipple. After cutaneous biopsy and gynecological staging study, she was diagnosed with skin invasion of mucinous carcinoma of the breast. We describe the main features of this rare tumor and the controversies in its diagnosis because primary and metastatic mucinous carcinomas in skin are histologically indistinguishable.

Successful treatment of pityriasis rubra pilaris with adalimumab - case report

Pityriasis Rubra Pilaris (PRP) is an uncommon skin disorder characterized by follicular keratosis, palmoplantar keratoderma, and erythroderma. The traditional preferred treatment is oral retinoids, but over the last decade, biologic therapy with anti-TNF agents has been used with success. We report the case of a 51 year- old man with a clinical and histopathological diagnosis of PRP. He underwent therapy with adalimumab and showed clearance of skin lesions within the fourth week of treatment.

A case of bullous erythema ab igne accompanied by anemia and subclinical hypothyroidism

Erythema ab igne (EAI) is a dermatosis characterised by reticulate red-brown pigmentation and telengiectasia resulting from long-term exposure to infrared radiation. It generally occurs in individuals using heating devices in the winter, those who frequently use hot compresses, and those who prefer hot environments. It generally occurs on the feet of women but may also occur on the hips and thighs. A 42-year-old male presented with red-brown spots and blisters on both thighs and behind the legs. He was diagnosed with EAI based on the clinical, historical, and histopathological features presented. Herein we present a case of bullous EAI associated with normochromic normocytic anemia and subclinical hypothyroidism.

Photo Vignette

Edematous lip in a HIV patient on highly active antiretroviral therapy

A 59-year-old HIV-positive, hepatitis C positive man on highly active antiretroviral therapy presented with a 2-year history of extreme swelling of the lower lip. Granulomatous cheilitis was diagnosed.

A perforating pilomatricomal horn on the arm of an 11-year-old girl

Cutaneous horns are uncommon in adults and rare in the pediatric population. Although verruca vulgaris, solar keratosis, and squamous cell carcinoma are more common entities that can present as cutaneous horns in the general population, conditions such as molluscum contagiosum, juvenile xanthgranuloma, and pyogenic granuloma have been reported causes in the pediatric population. We present a case of a perforating pilomatricoma presenting as a cutaneous horn in an 11 year old girl.

Primary milia localized to the vulva

Multiple primary milia were found on the vulva of a 52-year-old woman who was referred to the dermatology clinic by her gynecologist. These lesions are commonly distributed on the face and rarely occur in this location without antecedent trauma. This report demonstrates the unique presentation of primary milia in the genital region and explores the diagnostic features and treatment methods of these lesions.

Pigmented Bowen's disease of the penis and scrotum in a patient with AIDS

Patients with HIV have higher risk of developing squamous cell carcinoma of the skin given the increased risk of HPV infection, which alters cell proliferation and apoptosis [1]. Pigmented Bowen’s disease is an uncommon form of squamous cell carcinoma in-situ characterized by pigmented lesions that can clinically mimic superficial spreading melanoma, pigmented basal cell carcinoma, melanocytic nevus, Bowenoid papulosis, and seborrheic keratosis


Lymphomatoid papulosis and recurrent transitional cell carcinoma of the bladder: a paraneoplastic association

Lymphomatoid papulosis is a rare, papulonodular skin eruption with histologic features of a CD30+ T cell lymphoma. We present a 79-year-old man with lymphomatoid papulosis and transitional cell carcinoma of the bladder.

Multiple lentigines in areas of resolving psoriatic plaques after ustekinumab therapy.

The development of lentigines in areas previously involved by psoriasis has been reported in the literature, classically related to phototherapy but also to topical products. More recently, some authors have described several cases of lentigines appearing in resolving psoriatic plaques during or after treatment with anti-tumour necrosis factor (TNF) drugs used to treat severe plaque psoriasis, including adalimumab, etanercept, and infliximab. We report the case of a patient that developed multiple lentigines after clearance of the plaques of psoriasis receiving treatment with ustekinumab for his psoriasis.

Follicular unit extraction with the Artas robotic hair transplant system system: an evaluation of FUE yield

Hair transplants were developed and championed by dermatologists. However, dermatology literature has few contributions from within our specialty. In this manuscript, we present our evaluation of a specific graft harvesting approach for hair transplants referred to as Follicular unit extraction (FUE). In particular, we sought to evaluate the rate of harvest attempts that did not produce an actual hair folliclular unit graft.