Ectoparasites: Pediculosis and tungiasis.

Pediculosis is an infestation of lice on the body, head, or pubic region that occurs worldwide. Lice are ectoparasites of the order Phthiraptera that feed on the blood of infested hosts. Their morphotype dictates their clinical features. Body lice may transmit bacterial pathogens that cause trench fever, relapsing fever, and epidemic typhus, which are potentially life-threatening diseases that remain relevant in contemporary times. Recent data from some settings suggest that head lice may harbor pathogens. The epidemiology, clinical manifestations, and management of body, head, and pubic louse infestation are reviewed. New therapies for head lice and screening considerations for pubic lice are discussed. Tungiasis is an ectoparasitic disease caused by skin penetration by the female Tunga penetrans or, less commonly, Tunga trimamillata flea. It is endemic in Latin America, the Caribbean and sub-Saharan Africa and seen in travelers returning from these regions. Risk factors for acquiring tungiasis, associated morbidity, and potential strategies for prevention and treatment are discussed.

Ectoparasites: Scabies.

Scabies is an ectoparasitic dermatosis caused by Sarcoptes scabiei var. hominis and is a public health issue in all countries regardless of socioeconomic status. In high-income countries, delays in diagnosis can lead to institutional outbreaks; in low- and middle-income countries, poor access to health care contributes to disease undertreatment and long-term systemic sequelae. With scabies now recognized as a neglected tropical disease by the World Health Organization, increased awareness and systematic efforts are addressing gaps in diagnosis and treatment that impede scabies control. This review summarizes the available data and provides an update on scabies epidemiology, clinical features, diagnosis, management, and public health considerations.

Tularemia-induced erythema multiforme minor in an 11-year-old girl.

Tularemia is a rare and potentially life-threatening infection caused by the highly infectious gram-negative coccobacillus Francisella tularensis. We present the case of an 11-year old girl who presented with erythema multiforme minor in the setting of an indolent but progressive soft tissue infection and was found to have tularemia. We review the role of dermatologists in identifying the features of and complications associated with this rare zoonosis and discuss the potential effect of climate change on its incidence.

Pityriasis lichenoides: Long-term follow-up study.

BACKGROUND/OBJECTIVES: Pityriasis lichenoides is an uncommon papulosquamous disorder of unknown etiology. The objective of this study was to review the clinical features and treatment responses of individuals with pityriasis lichenoides seen at a tertiary referral center. METHODS: Seventy-five patients diagnosed with pityriasis lichenoides between 1997 and 2013 were reviewed, and 46 had long-term follow-up via telephone interviews. RESULTS: Fifty (67%) patients were diagnosed with pityriasis lichenoides chronica, 22 (29%) with pityriasis lichenoides et varioliformis acuta, and 3 (4%) with mixed pityriasis lichenoides chronica and pityriasis lichenoides et varioliformis acuta features. Mean ± standard deviation age at onset was 12 ± 13 years (median 8 years). Disease duration was significantly shorter for patients with pityriasis lichenoides et varioliformis acuta (35 ± 35 months) than for those with pityriasis lichenoides chronica (at least 78 ± 48 months). At long-term follow-up, 23 of 28 (82%) patients with pityriasis lichenoides chronica and 3 of 16 (19%) with pityriasis lichenoides et varioliformis acuta had active disease. None progressed to lymphomatoid papulosis or cutaneous T-cell lymphoma. Ten of 23 active pityriasis lichenoides chronica cases had residual pigmentary change independent of race and lasted at least 35 ± 20 months. The most effective treatments were phototherapy (47% response rate), heliotherapy (33%), topical corticosteroids (27%), and antibiotics (25%). CONCLUSION: Pityriasis lichenoides is a predominantly pediatric disorder. The time course of pityriasis lichenoides chronica is significantly longer than that of pityriasis lichenoides et varioliformis acuta. Pityriasis lichenoides chronica may persist with pigmentary alterations in the absence of other signs of active inflammation. Treatment response is often limited, particularly for patients with pityriasis lichenoides chronica.

Giant benign intradermal melanocytic nevus of rapid onset.

Benign melanocytic nevi are slowly growing acquiredor congenital tumors with varied morphology,commonly encountered in dermatology clinics. Anytumor with rapid clinical growth must be assessedcarefully in order to exclude malignancy. We report awoman with a histopathologically benign intradermalnevus that presented as a rapidly evolving largecutaneous mass on the ear. Owing to the discrepancybetween the clinical and histopathological findings,an extensive histopathological work-up involvingmany deeper sections, immunohistochemical stains,and fluorescent in situ hybridization (FISH) analysiswas conducted in order to rule out malignancy.

Teledermatology: from historical perspective to emerging techniques of the modern era: part I: History, rationale, and current practice.

Telemedicine is the use of telecommunications technology to support health care at a distance. Technological advances have progressively increased the ability of clinicians to care for diverse patient populations in need of skin expertise. Dermatology relies on visual cues that are easily captured by imaging technologies, making it ideally suited for this care model. Moreover, there is a shortage of medical dermatologists in the United States, where skin disorders account for 1 in 8 primary care visits and specialists tend to congregate in urban areas. Even in regions where dermatologic expertise is readily accessible, teledermatology may serve as an alternative that streamlines health care delivery by triaging chief complaints and reducing unnecessary in-person visits. In addition, many patients in the developing world have no access to dermatologic expertise, rendering it possible for teledermatologists to make a significant contribution to patient health outcomes. Teledermatology also affords educational benefits to primary care providers and dermatologists, and enables patients to play a more active role in the health care process by promoting direct communication with dermatologists.

Teledermatology: from historical perspective to emerging techniques of the modern era: part II: Emerging technologies in teledermatology, limitations and future directions.

Telemedicine is the use of telecommunications technology to support health care at a distance. Dermatology relies on visual cues that are easily captured by imaging technologies, making it ideally suited for this care model. Advances in telecommunications technology have made it possible to deliver high-quality skin care when patient and provider are separated by both time and space. Most recently, mobile devices that connect users through cellular data networks have enabled teledermatologists to instantly communicate with primary care providers throughout the world. The availability of teledermoscopy provides an additional layer of visual information to enhance the quality of teleconsultations. Teledermatopathology has become increasingly feasible because of advances in digitization of entire microscopic slides and robot-assisted microscopy. Barriers to additional expansion of these services include underdeveloped infrastructure in remote regions, fragmented electronic medical records, and varying degrees of reimbursement. Teleconsultants also confront special legal and ethical challenges as they work toward building a global network of practicing physicians.

An unusual breast lesion: granular cell tumor of the breast with extensive chest wall invasion.

Granular cell tumors (GCT) are generally benign soft tissue tumors. When located in the breast, they may be misdiagnosed as more typical tumors, such as invasive ductal carcinoma, based on misleading clinical or radiologic features. GCTs are frequently found in the setting of a known malignancy. We report the case of a patient with a large infra-mammary fold GCT, the management of which required a multidisciplinary operative approach due to extensive chest wall invasion.

Epidermotropic metastatic epithelioid sarcoma: a potential diagnostic pitfall.

Epithelioid sarcoma (ES) represents an aggressive soft tissue tumor with varied morphologic and histopathologic presentations that typically elicits a broad differential diagnosis, including granuloma annulare, necrobiotic granuloma, fibrous histiocytoma, synovial sarcoma, amelanotic melanoma and poorly differentiated primary cutaneous and metastatic adenocarcinoma. ES is characterized microscopically by a nodular arrangement of abundant, deeply eosinophilic, polygonal tumor cells with frequent central necrosis and hemorrhage, rare mitotic figures and minimal pleomorphism. At the periphery, tumor cells are spindle shaped and may exhibit frequent local infiltration along tendons, fascial planes and neurovascular bundles. Immunohistochemistry typically reveals expression of both epithelial and mesenchymal antigens, such as cytokeratin and vimentin, respectively. The absence of a connection between tumor cells and the overlying epidermis, with or without an in situ carcinoma component, typically rules out a primary cutaneous squamous cell carcinoma. We report a case of stage IV proximal-type ES that mimicked molluscum contagiosum clinically and was histopathologically reminiscent of invasive squamous cell carcinoma because of attachment and colonization of the overlying epidermis. The case represents an unusual pathologic presentation of ES and highlights potential pitfalls in establishing the diagnosis.

Ulcerative erythematous papules and plaques on the face and lower legs of a man living with HIV: a clinicopathological challenge.

A 44-year-old male presented with a 2-month history of erythematous ulcerative papules and plaques on the scalp, face, and bilateral lower legs. He had a 5-year history of well-controlled HIV on antiretroviral therapy and recurrent syphilis infections. His face had violaceous plaques, while bilateral ankles and calves had ulcerative lesions with necrotic centers and purple borders. The morphologies clinically mimicked pyoderma gangrenosum on the lower extremities and cutaneous lymphoma on the face. Biopsy and reactive rapid plasma reagin confirmed a diagnosis of lues maligna, and the patient was successfully treated with penicillin G benzathine.

Climate change, the cutaneous microbiome and skin disease: implications for a warming world.

The skin plays an important role in human health by providing barrier protection against environmental stressors. In addition to human skin cells, the cutaneous barrier is also home to a network of organisms that have co-evolved with humans, referred to as the cutaneous microbiome. This network has been demonstrated to play an active role in skin health and the manifestation of cutaneous disease. Here, we review how a warming world and its attendant changes in climatic variables, including temperature, humidity, ultraviolet radiation, and air pollution, influence the cutaneous microbiome and, in turn, skin health. Studies indicate that the cutaneous microbiome is affected by these factors, and these changes may influence the epidemiology and severity of cutaneous disorders including atopic dermatitis, acne vulgaris, psoriasis, and skin cancer. Further investigation into how the cutaneous microbiome changes in response to climate change and subsequently influences skin disease is needed to better anticipate future dermatologic needs and potentially generate novel therapeutic solutions in response.

Dengue: updates for dermatologists on the world's fastest-growing vector-borne disease.

Dengue is the world's fastest-growing vector borne disease and has significant epidemic potential in suitable climates. Recent disease models incorporating climate change scenarios predict geographic expansion across the globe, including parts of the United States and Europe. It will be increasingly important in the next decade for dermatologists to become familiar with dengue, as it commonly manifests with rashes, which can be used to aid diagnosis. In this review, we discuss dengue for general dermatologists, specifically focusing on its cutaneous manifestations, epidemiology, diagnosis, treatment, and prevention. As dengue continues to spread in both endemic and new locations, dermatologists may have a larger role in the timely diagnosis and management of this disease.

Addressing Climate-Related Health Impacts During the Patient Encounter: A Practical Guide for Pediatric Dermatologists.

Pediatric populations are expected to bear most of the climate change impacts, with racial minorities and children living in poorer countries being particularly vulnerable. Given their relevance to cutaneous disease, dermatologists should be aware of these climate-sensitive health impacts and the ways in which they intersect with social factors. Strategies including targeted risk communication, motivational interviewing, and storytelling can help facilitate climate discussions during the patient encounter. In this article the authors summarize common dermatologic health impacts related to environmental exposures and provide sample scripts for climate messaging.

Climate change, human migration, and skin disease: is there a link?

Climate change, exemplified by higher average global temperatures resulting in more frequent extreme weather events, has the potential to significantly impact human migration patterns and health. The consequences of environmental catastrophes further destabilize regions with pre-existing states of conflict due to social, political, and/or economic unrest. Migrants may carry diseases from their place of origin to their destinations and once there may be susceptible to diseases in which they had not been previously exposed to. Skin diseases are among the most commonly observed health conditions observed in migrant populations. To improve awareness among dermatologists of the burden of skin diseases among migrants, the group searched the English language scientific literature to identify articles linking climate change, migration, and skin disease. Skin diseases associated with human migration fall into three major categories: (i) communicable diseases, (ii) noncommunicable diseases, and (iii) environmentally mediated diseases. Adopting comprehensive global strategies to improve the health of migrants requires urgent attention.

The effects of climate change on infectious diseases with cutaneous manifestations.

BACKGROUND: Anthropogenic climate change affects the burden of infectious diseases via several interconnected mechanisms. In recent years, there has been greater awareness of the ways in which climate-sensitive infectious diseases pose a growing threat to global public health. OBJECTIVE: This study aimed to categorize and describe the effects of climate change on infectious diseases with skin manifestations. METHODS: A scoping review of the MEDLINE and PubMed online databases for climate-sensitive infections was performed in February and March 2020. A representative selection of conditions with skin manifestations was included in this review. RESULTS: Several representative climate-sensitive infectious diseases were identified in each of the following categories: vector-borne infectious diseases, infectious diseases associated with extreme weather events, and infectious diseases linked to human migration. CONCLUSION: Climate variables directly influence the survival and reproduction of infectious microorganisms, their vectors, and their animal reservoirs. Due to sustained warmer temperatures at higher latitudes, climate change has expanded the geographic range of certain pathogenic microbes. More frequent climate change-related extreme weather events create circumstances where existing infectious microorganisms flourish and novel infections emerge. Climate instability is linked to increased human migration, which disrupts health care infrastructure as well as the habitats of microbes, vectors, and animal reservoirs and leads to widespread poverty and overcrowding. Dermatologists should understand that climate change will affect the burden and geographic distribution of infectious diseases, many of which have cutaneous signs and might be encountered in their regular practice.

Implementing a Locally Made Low-Cost Intervention for Wound and Lymphedema Care in Western Kenya.

In Western Kenya, the burden of chronic wounds and lymphedema has a significant impact on functionality and quality of life. Major barriers to provision of care include availability, affordability, and accessibility of bandages. At the Academic Model Providing Access to Healthcare, dermatologists and pharmacists collaborated to develop a 2-component compression bandage modeled after the Unna boot, using locally available materials, that is distributed through a revolving fund pharmacy network. In partnership with nursing, use of these bandages at a national referral hospital and a few county facilities has increased, but increasing utilization to an expanded catchment area is needed.

The effects of climate change on human health in Africa, a dermatologic perspective: a report from the International Society of Dermatology Climate Change Committee.

Throughout much of the African continent, healthcare systems are already strained in their efforts to meet the needs of a growing population using limited resources. Climate change threatens to undermine many of the public health gains that have been made in this region in the last several decades via multiple mechanisms, including malnutrition secondary to drought-induced food insecurity, mass human displacement from newly uninhabitable areas, exacerbation of environmentally sensitive chronic diseases, and enhanced viability of pathogenic microbes and their vectors. We reviewed the literature describing the various direct and indirect effects of climate change on diseases with cutaneous manifestations in Africa. We included non-communicable diseases such as malignancies (non-melanoma skin cancers), inflammatory dermatoses (i.e. photosensitive dermatoses, atopic dermatitis), and trauma (skin injury), as well as communicable diseases and neglected tropical diseases. Physicians should be aware of the ways in which climate change threatens human health in low- and middle-income countries in general, and particularly in countries throughout Africa, the world's lowest-income and second most populous continent.

Implementation of an Ultraviolet Phototherapy Service at a National Referral Hospital in Western Kenya: Reflections on Challenges and Lessons Learned.

INTRODUCTION: In order to manage skin conditions at a national referral hospital level in Kenya, specialized dermatology services, such as dermatologic surgery, dermatopathology, phototherapy, and sub-specialty care, should be offered, as is typically available in referral hospitals around the world. A Kenyan patient with prurigo nodularis, whose severe itch remitted after phototherapy treatment at the University of California, San Francisco (UCSF), inspired the development of a phototherapy service at Academic Model Providing Access to Healthcare (AMPATH), a partnership in Western Kenya between Moi Teaching and Referral Hospital, Moi University College of Health Sciences, and a consortium of North American academic medical centers. METHODS: Initial project funds were raised through a crowdfunding campaign and fundraising events. A new narrowband ultraviolet B phototherapy unit and replacement bulbs were donated and air shipped to Eldoret, Kenya. A team of dermatologists and phototherapy nurses from UCSF conducted a 2-day training session. US-based dermatologists affiliated with AMPATH provide ongoing support through regular communication and on-site visits. RESULTS: Early in implementation, challenges faced included training clinical staff with limited experience in phototherapy and improving communication between nurses and clinicians. More recent challenges include frequent rotation of specialty clinic nurses in the dermatology clinic, adaptation of phototherapy guidelines to balance patient volume with service delivery capacity, and training assessment of disease activity in darkly pigmented skin. CONCLUSION: Strategies that have been helpful in addressing implementation challenges include: increasing on-site and remote training opportunities for clinicians and nurses, developing a tiered payment schema, educating patients to combat misconceptions about phototherapy, dynamic phototherapy referral guidelines to accommodate service delivery capacity, and prioritizing the engagement of a multidisciplinary team.

What's new in HIV dermatology?

HIV has long been associated with a number of inflammatory, infectious, and neoplastic skin conditions. In the era of anti-retroviral therapy, we have discovered even more about the relationship between skin disease and chronic immunosuppression. In particular, clinicians still face the propensity of persons living with HIV to develop difficult-to-control viral infections, chronic skin inflammation, and pruritus and-particularly as patients age-various types of skin cancers. Here, we summarize recent updates in the field of HIV dermatology and make recommendations to providers caring for these patients.

Temperature and humidity affect the incidence of hand, foot, and mouth disease: a systematic review of the literature - a report from the International Society of Dermatology Climate Change Committee.

Hand, foot, and mouth disease (HFMD) is an enterovirus-mediated condition that predominantly affects children under 5 years of age. The tendency for outbreaks to peak in warmer summer months suggests a relationship between HFMD and weather patterns. We reviewed the English-language literature for articles describing a relationship between meteorological variables and HFMD. Seventy-two studies meeting criteria were identified. A positive, statistically significant relationship was identified between HFMD cases and both temperature (61 of 67 studies, or 91.0%, reported a positive relationship) [CI 81.8-95.8%, P = 0.0001] and relative humidity (41 of 54 studies, or 75.9%) [CI 63.1-85.4%, P = 0.0001]. No significant relationship was identified between HFMD and precipitation, wind speed, and/or sunshine. Most countries reported a single peak of disease each year (most commonly early Summer), but subtropical and tropical climate zones were significantly more likely to experience a bimodal distribution of cases throughout the year (two peaks a year; most commonly late spring/early summer, with a smaller peak in autumn). The rising global incidence of HFMD, particularly in Pacific Asia, may be related to climate change. Weather forecasting might be used effectively in the future to indicate the risk of HFMD outbreaks and the need for targeted public health interventions.