Intralesional amphotericin B in a cat with cutaneous protothecosis

A domestic cat was presented with nodular lesions on the nose/muzzle and pinnae. Protothecosis was diagnosed through cytological and histopathological examination, and culture. Molecular identification confirmed Prototheca wickerhamii infection. Intralesional application of amphotericin B in conjunction with oral terbinafine resulted in a significant reduction of the nasal lesion and complete resolution of the pinnal lesion, without adverse effects.

Human Disseminated Protothecosis: The Skin is the “Window”?

Human disseminated protothecosis is a rare infection caused by members of the genus Prototheca, an achlorophyllic algae always associated with debilitated hosts. The presence of non-budding cells and large, spherical cells (sporangia) with endosporulation (morula) in histology is proof of Prototheca infection. Regrettably, due to the lack of specificity of clinical features and low awareness among clinicians, protothecosis is always underestimated and misdiagnosed. The available data on a species-specific analysis of this infection are limited. In this review, we summarize the etiological, epidemiological, and clinical aspects of disseminated protothecosis. The potential pathogenicity and clinical differences between P. zopfii and P. wickerhamii were observed. Additionally, the skin not only became the main invasion site but also the most involved organ by the pathogen. With the increasing numbers of immunocompromised individuals throughout the world, the incidence of disseminated infection caused by Prototheca is bound to increase, and disseminated protothecosis that accompanies skin symptoms should be taken into account by clinicians.

Histopathologic Spectrum of Findings Associated With Tattoos: Multicenter Study Series of 230 Cases

IMPORTANCE

Reactions to tattoo may simulate common dermatosis or skin neoplasms. Histopathology allows diagnosis and helps determining the level and degree of inflammation associated, consequently orientating treatment.

OBJECTIVE

To describe the histological features found in biopsies of cutaneous reactions to tattoo.

DESIGN

This study was designed as a multicenter case series.

SETTING

All consecutive histopathological samples of tattoos referred from 1992 to 2019 to the Hospital General de Catalunya, Hospital Germans Trias i Pujol, and a private practice, all in Barcelona, Spain, and from the Kempf und Pfaltz Histologische Diagnostik in Zurich, Switzerland were retrieved from the files.

PARTICIPANTS AND EXPOSURE

The inclusion criteria were all cosmetic/permanent makeup, artistic/professional, and traumatic tattoos associated with either inflammatory reactions alone and/or with tumors and/or infections. Exclusion criteria were cases without any associated pathologic finding in the place of the ink, amalgam tattoos, and medical or temporary tattoos.

MAIN OUTCOMES AND MEASURES

In all patients, clinical features (age, sex, location, tattoo color, and presentation) were recorded. Histological features evaluated included ink color, associated tumors or infections, and inflammatory reaction pattern. Inflammation was graded in low to moderate or severe.

RESULTS

From 477 biopsies diagnosed as tattoos, 230 cases from 226 patients met the inclusion criteria. Samples corresponded to 107 male and 120 female subjects and 3 of unknown gender. Median age was 39 years (ranging from 9 to 84 years). Fifty-three samples were referred from centers in Spain and 177 from the center in Switzerland. The series was analyzed in 2 parts: tattoos associated only with inflammatory reactions (117/230) and tattoos associated with tumors or infections (113/230). The most common form of inflammatory pattern associated with tattoo was the fibrosing reaction (79/117, 68%), followed by granulomatous reaction (56/117, 48%), lichenoid reaction (33/117, 28%), epithelial hyperplasia (28/117, 24%), pseudolymphoma (27/117, 23%) and spongiotic reaction (27/117, 23%). Combined features of 2 or more types of inflammatory patterns were seen in 64% cases.

CONCLUSIONS AND RELEVANCE

Our series confirms that cutaneous reactions to tattoos are polymorphous. Inflammation tends to present with combined patterns. Infections are tending to decline, and pathologic findings are not specific to ink color or clinical features.

Cellulitis: A Review of Pathogenesis, Diagnosis, and Management

Cellulitis is a common skin infection resulting in increasing hospitalizations and health care costs. There is no gold standard diagnostic test, making cellulitis a potentially challenging condition to distinguish from other mimickers. Physical examination typically demonstrates poorly demarcated unilateral erythema with warmth and tenderness. Thorough history and clinical examination can narrow the differential diagnosis of cellulitis and minimize unnecessary hospitalization. Antibiotic selection is determined by patient history and risk factors, severity of clinical presentation, and the most likely microbial culprit.

Common Cutaneous Infections: Patient Presentation, Clinical Course, and Treatment Options

This evidence-based review highlights cutaneous infections of bacterial, viral, and fungal origin that are frequently encountered by clinicians in all fields of practice. With a focus on treatment options and management, the scope of this article is to serve as a reference for physicians, regardless of field of specialty, as they encounter these pathogens in clinical practice.

Disseminated cryptococcosis presenting with cutaneous involvement in an immunocompromised patient

Cryptococcosis is a fungal infection that typically affects immunocompromised patients. It most commonly affects the lungs and may then disseminate to the central nervous system, bone, skin, and adrenal glands. Herein, we describe a 69-year-old man who presented with skin lesions as the initial manifestation of disseminated cryptococcosis. Initial workup led to an assumption that the patient was immunocompetent. Later in the clinical course, idiopathic depletion of CD4 T cells was discovered. This case highlights that disseminated cryptococcosis may present with cutaneous symptoms even when there is no evidence of pulmonary or central nervous system involvement and may be the first sign of an underlying cellular immune dysfunction.

Refractory Human Cutaneous Protothecosis

A 67-year-old Scottish woman presented to her general practitioner with a subcentimeter lump between her shoulder blades. The lump was suspected to be an epidermal cyst and was excised. The patient had a history of controlled diabetes. Most summers, she spent a month near a beach resort in Mexico. The lump reappeared after 6 months within the scar area and was re- excised. Both skin excisions were performed in the primary care setting without histologic assessment.

Reflectance confocal microscopy for the diagnosis of skin infections and infestations

Reflectance confocal microscopy (RCM) is a noninvasive real-time imaging technique that has been widely used for the diagnosis of skin cancer. More recently, it has been reported as a useful tool for the diagnosis and management of several inflammatory and infectious skin disorders. This article provides an overview of the current available applications of RCM use in cutaneous infections and infestations. PubMed was used to search the following terms in various combinations: reflectance confocal microscopy, skin, hair, nail, infection, parasitosis, mycosis, virus, bacteria. All papers were accordingly reviewed. In most cutaneous infections or infestations, the main alterations are found in the epidermis and upper dermis, where the accuracy of confocal microscopy is nearly similar to that of histopathology. The high resolution of this technique allows the visualization of most skin parasites, fungi, and a few bacteria. Although viruses cannot be identified because of their small size, viral cytopathic effects can be observed on keratinocytes. In addition, RCM can be used to monitor the response to treatment, thereby reducing unnecessary treatments.

Skin Lesions: Mirror Images of Oral Lesion Infections

Skin lesions can be the presenting signs for HIV disease and are among the most prevalent manifestations throughout the course of HIV disease. Correlation of skin diseases and HIV disease staging has long been recognized and used to guide medical management in resource-limited settings. The purpose of this paper is to give a review of common skin infections presented in HIV-infected patients. Common skin infections presenting in HIV-infected patients include viral, fungal, mycobacterial, and bacterial infections, along with skin infestation. Key diagnostic points correlate with certain HIV disease staging for many skin diseases. These can help facilitate appropriate diagnosis and referral by health care personnel when treating HIV-infected patients who have skin lesions. Knowledge of common skin manifestations found in HIV-infected patients is essential for all health care personnel who work in the HIV field. Most skin infections presenting in HIV-infected patients can be treated effectively if the correct diagnosis and appropriate referral are made promptly.

Severe Persistent Orf in Young Goats

Orf (contagious ecthyma) is a viral disease of small and wild ruminants, humans, and less frequently other species. In sheep and goats, the disease is characterized by the formation of vesiculo-proliferative lesions in the skin of lips and nostril. Here, a form of generalized orf in 16 goat kids from 2 different locations in west Texas is described. The disease was characterized by multifocal, severe, proliferative dermatitis that persisted from about 2 months of age until the goat kids were euthanized 3 months later. All affected goats were Boer or Boer crosses under 1 year of age. The mean immunoglobulin concentration in sera of affected goats was elevated compared with healthy control goats. Severe to moderate lymphadenomegaly of the nodes draining the areas of the skin affected with orf lesions was present in all 16 goat kids. Suppurative arthritis, chronic fibrinous pneumonia, and premature thymic involution were found in 3, 5, and 7 of the goat kids, respectively. The skin lesions of 3 goat kids were infested with larvae of the opportunistic black garbage fly ( Ophira sp.). The orf virus was identified in skin lesions by isolation in Marbin—Darby ovine kidney cells, electron microscopy, and amplification of viral DNA by polymerase chain reaction. The orf virus was not detected in peripheral blood or lymph node mononuclear cells of any of the goats. Cross-neutralization experiments showed that an ovine orf virus antiserum raised in sheep was more effective in neutralizing a sheep orf virus isolate than a caprine orf virus isolate. The clinical and epidemiological characteristics of these orf cases may be the result of susceptibility factors within some individuals of the Boer breed of goats.

[Cutaneous granulomatosis]

Granulomatous skin diseases represent a large group of reactive dermatoses occurring in response to different stimuli and whose skin biopsy is characterized by a granulomatous inflammatory infiltrate. By their very heterogeneous clinical presentation, it seems difficult to distinguish them and make their diagnosis. Clinically, it may be useful to separate localized forms of disseminated forms of cutaneous granulomatosis, although this distinction is often artificial. We will discuss here the main forms of localized and disseminated cutaneous granulomatosis, and, in light of recent literature data, mention different therapeutic options in each case.

[The skin microbiota: a colossus steps into the spotlight]

The skin contains many commensal bacteria. For years, these microbes have been considered to be exploiters of the human host for nutrients. However, recent findings indicates that the skin microbiota is also used by the human host to protect himself against invading pathogens as the commensal bacteria have direct antimicrobial capacity and provide factors required to mount a protective immune responses in the skin. While the healthy skin microbiome functions as guardians of host defense, increased or decreased bacterial composition of the skin microbiome (called dysbiosis) leads to skin inflammation and disease. Here we will review the emerging data on the role of distinct types of dysbiosis in the pathogenesis skin diseases and illustrate how the new understanding of the role of the skin microbiome has implications in the clinical management of skin diseases.

Pitfalls in diagnosing diabetic foot infections

Although the diagnosis of a diabetic foot infection is made based on clinical symptoms and signs, we also use blood laboratory, microbiological and radiological studies to make treatment decisions. All of these diagnostic studies have pitfalls that can lead to a delay in diagnosis. Such delays will likely lead to further tissue damage and to a higher chance of amputation. One of these pitfalls is that some clinicians rely on microbiological, rather than clinical data, to diagnose infection. Though subjective by nature, clinical signs predict outcome of foot infections accurately. Another pitfall is that microbiological data can be misleading. All wounds harbour microorganisms; therefore, a positive wound culture does not mean that a wound is infected. Furthermore, the outcome of cultures of wound swabs does not correlate well with culture results of tissue biopsies. Therapy guidance by wound swab will likely lead to overtreatment of non-pathogenic organisms. Genotyping might have a role in identifying previously unrecognized (combinations of) pathogens in diabetic foot infection, bacteria in sessile phenotype and non-culturable pathogens, e.g. in cases where antibiotics have already been administered. One more pitfall is that the diagnosis of osteomyelitis remains difficult. Although the result of percutaneous bone biopsy is the reference standard for osteomyelitis, some other diagnostic modalities can aid in the diagnosis. A combination of several of these diagnostic tests is probably a good strategy to achieve a higher diagnostic accuracy. Relying on a single test will likely lead to misidentification of patients with osteomyelitis with associated overtreatment and undertreatment.

Reflectance confocal microscopy in infectious diseases

In vivo reflectance confocal microscope (RCM) is a high-resolution non-invasive imaging technique that was initially focused on the diagnosis of skin cancers. A rising number of other indications have been later described for the diagnosis and management of inflammatory and infectious dermatological disorders. RCM can identify cutaneous parasites that are not visible to naked eye such as Sarcoptes scabiei and Demodex folliculorum and it allows to better identify the different body parts of bigger parasites such as ticks. Fungal filaments can also be identified as elongated bright structures in the cutaneous upper layers. RCM cannot observe virus directly. However, the cytopathic effect associated with some virus can be recognized. In addition of being helpful for the diagnosis and follow-up after treatment, thanks to its non-invasiveness, RCM allows pathophysiological studies.

Dermatoscopy in inflammatory and infectious skin disorders

Dermatoscopy is a non-invasive technique that allows a rapid and magnified in vivo observation of the skin surface. By definition, it is performed with handheld devices (dermatoscopes) allowing X10 magnification. More expensive, computer-assisted digital systems (videodermatoscopes) may be equipped with lenses that ensure magnifications up to X1000; in this case the term videodermatoscopy is generally used. Dermatoscopy is mainly utilized for the evaluation of pigmented skin lesions, and has increasing applications in dermatology. In this paper the use of dermatoscopy in a variety of inflammatory (psoriasis, lichen planus, pityriasis lichenoides, rosacea, lichen sclerosus, Darier's disease, pigmented purpuric dermatoses) and infectious (human papillomaviruses infections, molluscum contagiosum, tinea capitis, tinea nigra, scabies, head and pubic lice, tungiasis, cutaneous leishmaniasis and cutaneous larva migrans) cutaneous disorders will be analyzed. In these conditions, dermatoscopy may assist the clinical diagnosis, reducing the need of semi-invasive or invasive procedures such as skin scrapings and/or biopsy. Depending on the disease, the choice to use low or high magnifications may be crucial. Dermatoscopy may also be useful for prognostic evaluation and monitoring of response to treatment, representing an important and relatively simple aid in daily clinical practice.

Septic vasculitis and vasculopathy in some infectious emergencies: the perspective of the histopathologist

Sepsis is a potentially life-threatening complication of an infection where cutaneous lesions often represent one of the early signs. A myriad of microorganisms including bacteria, fungi, yeasts, viruses, protozoas, helminths and algae can be implicated. A broad spectrum of clinical and histopathologic findings can be observed in the skin and the common denominator is a thrombotic vasculopathy. The pathogenesis of cutaneous septic vasculitis (SV)/vasculopathy is complex and includes five main mechanisms: disseminated intravascular coagulation, direct invasion and occlusion of blood vessel walls by microorganisms, hypersensitivity reaction with immune complex deposition into blood vessel walls, embolism from a distant infectious site and vascular effects of toxins. Herein we describe the clinicopathologic findings of some selected cases of SV recently observed in our hospital, including purpura fulminans, necrotizing fasciitis, cutaneous meningococcemia, malignant syphilis and disseminated alternaria infection. Histopathologically, a wide spectrum of histopathologic changes was observed in skin specimens from the various entities, involving the intensity and composition of the inflammatory infiltrate, the degree of vascular changes and the presence of microorganisms, that ranged from a predominant not inflammatory, thrombotic-occlusive vasculopathy in purpura fulminans to leukocytoclastic vasculitis like changes in cutaneous meningococcemia to a dermal angiomatosis-like pattern in disseminated Alternaria infection. The different pathologic presentations may be related to the microorganism involved, the main pathogenetic mechanism that induced the vascular injury and the individual immunologic burden. Early skin biopsy for histopathologic examination and microbiologic culture is a cornerstone in the diagnosis of life-threatening diseases that present with cutaneous septic vasculitis. Ancillary techniques, such as immunohistochemistry and polymerase chain reaction are additional novel and helpful tools to identify pathogens, leading to definite diagnosis in cases with challenging or ambiguous clinical and/or pathologic findings.

A case of primary cutaneous mucormycosis caused by minor trauma

We present the case of a 66-year-old neutropenic man with mantle-cell lymphoma who presented for evaluation of a rapidly expanding necrotic eschar after a minor cutaneous injury. Histopathology revealed infection with Rhizopus indicating primary cutaneous mucormycosis. Our case reviews the presentation and management of this condition as well highlights the potential for minor cutaneous injuries in the hospital to lead to this dangerous infection.

Compensation for occupational skin diseases

The Korean list of occupational skin diseases was amended in July 2013. The past list was constructed according to the causative agent and the target organ, and the items of that list had not been reviewed for a long period. The revised list was reconstructed to include diseases classified by the International Classification of Diseases (10th version). Therefore, the items of compensable occupational skin diseases in the amended list in Korea comprise contact dermatitis; chemical burns; Stevens-Johnson syndrome; tar-related skin diseases; infectious skin diseases; skin injury-induced cellulitis; and skin conditions resulting from physical factors such as heat, cold, sun exposure, and ionized radiation. This list will be more practical and convenient for physicians and workers because it follows a disease-based approach. The revised list is in accordance with the International Labor Organization list and is refined according to Korean worker's compensation and the actual occurrence of occupational skin diseases. However, this revised list does not perfectly reflect the actual status of skin diseases because of the few cases of occupational skin diseases, incomplete statistics of skin diseases, and insufficient scientific evidence. Thus, the list of occupational diseases should be modified periodically on the basis of recent evidence and statistics.

Protothecosis

Protothecosis is a rare infection caused by achlorophyllic algae that are members of the genus Prototheca. They are ubiquitous in nature in organic material. The clinical manifestations can be acute or chronic and local or disseminated. The disease is classified as cutaneous, causing bursitis or disseminated/systemic, affecting both immunocompetent and immunosuppressed patients, with more severe and disseminated infections occurring in immunocompromised individuals. Prototheca wickerhamii and Prototheca zopfii are the most frequent organisms reported in humans. Diagnosis is made by observing asexual sporangia (thecas) on histopathological examination of tissue. Medical and surgical treatment should be considered. Ketoconazole, itraconazole, fluconazole, voriconazole, posaconazole, and amphotericin B are the most commonly used antifungals. Voriconazole and amphotericin B are highly effective against Prototheca spp. Treatment failure is not uncommon because of the comorbidities that limit the therapeutic outcome.

Nanotechnology and the diagnosis of dermatological infectious disease

Despite advances in diagnostics and therapeutics, infectious diseases continue to be a major cause of morbidity and mortality, surpassing cardiovascular diseases and cancer. Accurate identification of causative pathogens is critical to prevent the spread of infectious diseases and to deliver appropriate and timely therapy. Various limitations ranging from cost to lengthy yield times of current diagnostic modalities highlight the need for new approaches. Nanotechnology represents an innovative direction offering many advantages for pathogen detection and identification. Through surface modifications, nanoparticles can be tailored to bind microbial surface markers, nucleic acids, and toxins. Combining these nanoparticles with both standard and developing detection technologies has led to the development of faster, more sensitive, and more economical diagnostic assays. This review will focus on the diagnostic advances that utilize fluorescent, metallic, and magnetic nanomaterials, highlighting their potential applications in the diagnosis of infectious dermatological conditions.

Flexural and extensoral eruptions in dermatologic disease

Dermatologic eruptions can be generalized or localized to specific areas of the body. Eruptions in specific body regions may suggest specific diagnosis. Recognizing such clinical patterns can facilitate the identification of the underlying pathology. In this contribution, we shall discuss those dermatologic lesions that tend to affect the flexure and extensor surfaces.

[Cutaneous infections]

The epidermis, the human being's primary protection against infection and aggression, can crack or split, and result in microbial bacteria penetrating it. Infections may, however, stem from other sources, such as viruses which enter the body via the respiratory tract, and then appear on the skin.

Incidence of childhood dermatosis in India

The incidence ofdermatologic conditions in the pediatric age group presents a pattern that often differs from that in adults; this is important for epidemiologic studies and population-based analysis. This clinical study was carried out in children up to age 14 in the western part of India. Dermatologic conditions were tabulated based on the etiology, incidence, age, and sex distribution, as well as seasonal variations, and the results were analyzed. There were a total of 390 boys and 310 girls. The majority of skin conditions in newborns are transient. The most common dermatoses found were of infectious etiology (38.43%) in which impetigo (11.13%) and pyoderma (8.9%) were the most common. In infectious etiology, incidence of scabies was 5.32%. Viral warts were the most common viral infections followed by molluscum contagiosum. Incidence of eczema, atopic dermatitis, and sweat gland disorders were 6.64%, 0.83%, and 8.86%, respectively. The study shows various unique features of tropical pediatric dermatology in a developing country, such as high frequency of infections and infectious, nutritional, and environmentally associated disorders. Many of these dermatoses can be controlled by proper environmental sanitation, improving nutrition, awareness among parents and children, and preventing overcrowding.

Varying phenotypes in swine versus murine transgenic models constitutively expressing the same human Sonic hedgehog transcriptional activator, K5-HGLI2 Delta N

This study was undertaken to characterize the effects of constitutive expression of the hedgehog transcriptional activator, Gli2, in porcine skin. The keratinocyte-specific human transgene, K5-hGli2 Delta N, was used to produce transgenic porcine lines via somatic cell nuclear transfer techniques. In mice, K5-hGli2 Delta N induces epithelial downgrowths resembling basal cell carcinomas. Our porcine model also developed these basal cell carcinoma-like lesions, however gross tumor development was not appreciated. In contrast to the murine model, diffuse epidermal changes as well as susceptibility to cutaneous infections were seen in the swine model. Histologic analysis of transgenic piglets revealed generalized epidermal changes including: epidermal hyperplasia (acanthosis), elongated rete ridges, parakeratotic hyperkeratosis, epidermal neutrophilic infiltration, capillary loop dilation and hypogranulosis. By 2 weeks of age, the transgenic piglets developed erythematic and edematous lesions at high contact epidermal areas and extensor surfaces of distal limb joints. Despite antibiotic treatment, these lesions progressed to a deep bacterial pyoderma and pigs died or were euthanized within weeks of birth. Non-transgenic littermates were phenotypically normal by gross and histological analysis. In summary, constitutive expression of the human hGli2 Delta N in keratinocytes, results in cutaneous changes that have not been reported in the K5-hGli2 Delta N murine model. These findings indicate a need for a multiple species animal model approach in order to better understand the role of Gli2 in mammalian skin.

[Myonecrosis in users of injecting drugs (a clinical case)]

Myonecrosis remains one of the severest manifestations of skin and soft tissue infections. Clostridia (C. perfringens, C. novyi, C. septicum, C. sordellii, C. histolyticum) are dominant and Staphylococcus aureus, Streptococcus pyogenes, Bacillus cereus, and Bacteriodes fragilis are much less in the etiology of myonecrosis. Cases of gas gangrene have recently become more frequent among injection drug users all over the world. Russia has become the largest opiate market in Europe and consumption of these narcotic drugs is annually growing. In the Russian Federation, a larger number of injection drug users uniquely results in a rise of cases of Clostridium- and mixed flora-induced myonecrosis. Gas gangrene in HIV-positive drug abusers seems to rapidly progress to multiple organ failure and to show high death rates, rather than to develop a localized form. The analyzed case of mixed flora-induced gas gangrene is of interest to physicians of any specialties who can encounter this wound infection in HIV-positive patients.

[Skin and skin tissue infections: main clinical patterns/pictures]

Skin and soft tissue infections represent a heterogeneous group of clinical entities that require to be accurately identified for an appropriate and immediate management. Clinicians are challenged by the need to rapidly select those patients requiring hospitalization and medical therapy only and those to be immediately submitted to surgery. Erysipelas and several forms of cellulitis, involving the superficial structures of epidermis and dermis, are medical conditions; some cutaneous abscess may require surgical drainage, and all the necrotizing infections, involving the subcutaneous tissue (necrotizing fasciitis) or muscles (myonecrosis) are surgical conditions. Among the clinical clues useful for the diagnosis are the presence of severe pain disproportionate to the clinical evidence of the lesion (necrotizing fasciitis), the presence of crepitus (gas gangrene) and signs of systemic toxicity (high fever, hypotension, tachycardia, shock and multiple organ failure).

Cutaneous protothecosis: a case report and review of the literature

Protothecosis is a rare cause of systemic and/or cutaneous infection. Because approximately 100 cases of human infection with Prototheca wickerhamii have been reported, little is known about the pathogenesis of this infection. Cases include both immunocompetent and immunocompromised patients. However, most cases contain an element of immune compromise, either local or systemic. We present a case of an 81-year-old white woman with a history of multiple nonmelanoma skin cancers, including squamous and basal cell carcinomas and actinic keratoses, throughout her legs and thighs bilaterally. She presented to a central Florida dermatology clinic with complaints of persistent bumps on her right lower leg despite therapy with diclofenac sodium gel 3% and 5-fluorouracil cream 5%. Biopsies of skin specimens from the right lower leg revealed a dermal abscess that contained spherical funguslike organisms, with periodic acid-Schiff staining revealing 6- to 10-microm organisms with internal septations, which are characteristic of P wickerhamii.

Prototecose cutânea: relato de caso

Descreve-se um caso de prototecose cutânea em paciente de 78 anos, submetido a tratamento para pênfigo foliáceo e feohifomicose. Ele apresentava lesões eritematosas infiltradas na perna direita e o diagnóstico foi feito através de estudo histológico e através de cultura da pele lesada. A cura foi obtida com o uso oral de itraconazol.

Control of Pseudomonas aeruginosa skin infections in mice is mast cell-dependent

Mast cells (MCs) have recently been shown to be essential for the elicitation of efficient immune responses in murine sepsis. To explore whether MCs also contribute to the control of bacterial skin infections, we studied skin lesions induced by Pseudomonas aeruginosa (PA) in genetically MC-deficient Kit(W)/Kit(W-v) mice, normal Kit(+/+) mice, and MC-reconstituted Kit(W)/Kit(W-v) mice. PA injections resulted in strikingly (>2-fold) larger skin lesions in Kit(W)/Kit(W-v) mice than in Kit(+/+) mice, which exhibited pronounced MC degranulation at infection sites. In addition, neutrophil recruitment following PA injections and bacterial clearance from sites of infection was significantly impaired in Kit(W)/Kit(W-v) mice compared with Kit(+/+) mice. Notably, the adoptive transfer of MCs to the skin of Kit(W)/Kit(W-v) mice before PA infection resulted in normal neutrophil accumulation as well as skin lesions comparable with those in Kit(+/+) mice in both bacterial burden and size. These findings demonstrate for the first time that activated MCs are crucial for the induction of protective innate immune responses to bacterial skin infections.

Experimental cutaneous Bacillus anthracis infections in hairless HRS/J mice

Previous studies of experimental Bacillus anthracis cutaneous infections in mice have implicated hair follicles as a likely entry site. Hairless HRS/J mice were used to investigate this possibility because of their non-functional hair follicles that lack penetrating hair shafts. These mice also have diminished macrophage function, increased susceptibility to Listeria, and enhanced neutrophil responses. HRS/J and Balb/c mice were found to be resistant to epicutaneous inoculation with Bacillus anthracis (Sterne) spores onto abraded skin when compared with DBA/2 mice or leucopenic C57BL/6 mice. The HRS/J mice also resisted spore injections that bypassed hair follicles. Haired HRS/J heterozygote mice demonstrated similar reduced susceptibility to B. anthracis spores. Hairless HRS/J mice that were made leucopenic did become susceptible to the epicutaneous spore inoculations. Histologically, the hairless and haired HRS/J mice showed markedly reduced numbers of organisms in hair follicles and the interfollicular dermis when compared even with the resistant Balb/c mice; inflammatory cell infiltrates in the superficial dermis were increased in the HRS/J mice compared with more sensitive strains. Therefore, resistance in the HRS/J mice was apparent at the initial site of epicutaneous inoculation and seemed related to an accumulation of dermal neutrophils rather than to a lack of functional hair follicles.

Cutaneous Pseudovasculitis

Cutaneous pseudovasculitis represents a heterogeneous collection of disorders that are capable of simulating cutaneous vasculitis and can be broadly classified into diseases that produce hemorrhage (petechiae, purpura, and ecchymoses) or vessel occlusion with resultant livedo, cyanosis, ulcers, digital necrosis, and/or gangrene. Overlap is not uncommon, but if present, one mechanism dominates. Hemorrhagic pseudovasculitis is due to vessel wall dysfunction (incompetence), which can be related to diverse factors that include vessel wall deposition of metabolic substances (amyloid, calcium), nutritional deficiencies (scurvy), nonvasculitic inflammatory purpura (pigmented purpuric dermatitis, arthropod, viral and drug reactions), degeneration of the vessel wall and supporting stroma (senile/solar purpura), direct vessel wall invasion of infective organisms, coagulation-fibrinolytic disorders (eg, thrombocytopenia), and vessel wall trauma. Cyanotic-infarctive pseudovasculitis is due vaso-occlusion by emboli, thrombi, or fibrointimal hyperplasia (endarteritis obliterans) and includes varied conditions such as purpura fulminans, Coumadin necrosis, antiphospholipid antibody syndrome, cardiac myxoma, cholesterol embolization, calciphylaxis, and radiation arteritis. Delayed and inappropriate diagnosis of pseudovasculitis leads to incorrect management and exposure to potentially deleterious treatment modalities such as corticosteroids and cytotoxic agents. The diagnosis of a pseudovasculitic disorder requires a high index of suspicion and should always be part of the differential diagnosis of vasculitis. Skin biopsy is a crucial step in differentiating pseudovasculitis from authentic vasculitis; absence of histologic evidence of vasculitis, particularly after multiple biopsies, should direct evaluation and diagnosis towards pseudovasculitis.

Fournier gangrene

Fournier gangrene is a necrotizing infection involving the soft tissues of the male genitalia. It was first described in 1764 by Baurienne and given its eponymous name after Jean-Alfred Fournier in 1883 presented a case of perineal gangrene in an otherwise healthy young man. While only 600 cases of Fournier gangrene have been reported in the world literature since 1996, it is a common and serious disease in Africa. In Maputo Central Hospital alone, between 12 and 16 cases are admitted every year and treated with a 20% mortality. The typical patient is an elderly male in his sixth or seventh decade with co-morbid diseases. While considered to affect males only, a similar condition may occasionally affect the female genitalia.

Essential functions of the unique N-terminal region of the varicella-zoster virus glycoprotein E ectodomain in viral replication and in the pathogenesis of skin infection

Varicella-zoster virus (VZV) glycoprotein E (gE) is a multifunctional protein important for cell-cell spread, envelopment, and possibly entry. In contrast to other alphaherpesviruses, gE is essential for VZV replication. Interestingly, the N-terminal region of gE, comprised of amino acids 1 to 188, was shown not to be conserved in the other alphaherpesviruses by bioinformatics analysis. Mutational analysis was performed to investigate the functions associated with this unique gE N-terminal region. Linker insertions, serine-to-alanine mutations, and deletions were introduced in the gE N-terminal region in the VZV genome, and the effects of these mutations on virus replication and cell-cell spread, gE trafficking and localization, virion formation, and replication in vivo in the skin were analyzed. In summary, mutagenesis of the gE N-terminal region identified a new functional region in the VZV gE ectodomain essential for cell-cell spread and the pathogenesis of VZV skin tropism and demonstrated that different subdomains of the unique N-terminal region had specific roles in viral replication, cell-cell spread, and secondary envelopment.

Reactivation of dormant cutaneous Leishmania infection in a kidney transplant patient

BACKGROUND

Leishmaniasis is an infection caused by a protozoan parasite belonging to genus Leishmania and transmitted by the Phlebotomus sandfly. Clinical presentations of infection include visceral, cutaneous, and mucocutaneous forms. Leishmaniasis is endemic in Africa, Asia, Europe, South America, and southern part of North America. This infection is extremely rare in the US and is mostly found among travelers coming from endemic areas. Cases of cutaneous and visceral leishmaniasis have been reported in organ transplant recipients in endemic areas.

CASE REPORT

We describe a case of cutaneous leishmaniasis in a kidney transplant patient, originally from Bolivia, who resides in the area known to be non-endemic for leishmaniasis and who is known not to travel within or outside of the US after the transplantation.

RESULTS

Histologic examination of cutaneous lesion revealed extensive subcutaneous lymphohistiocytic inflammation with clusters of amastigote within histiocytes.

CONCLUSION

To our knowledge, this is the first case of cutaneous leishmaniasis in a kidney transplant patient residing in the US in an area known to be non-endemic for leishmaniasis, probably after reactivation of a previously dormant infection acquired outside of the US at least 9 months prior to developing clinical symptoms.

What is That Nodule?

The evaluation of patients with subcutaneous nodules remains a diagnostic challenge. The presence of nodules can be a clue to an underlying systemic disease; however, the varied presentations of nodules and numerous disease associations make the assessment of patients with nodules far from simple. With further investigation into the appearance, location, and symptoms associated with nodules, the clinical significance of these lesions can become clearer and aid in logical diagnostic evaluation. We have reviewed the causes of nodules with emphasis on those associated with rheumatic disease and provide guidelines for nodule evaluation to better characterize disease association and lead to directed diagnostic assessment.

Practical cytology for inflammatory skin diseases

Cytology is the most common and immediately informative diagnostic tool in the practice of dermatology. It is simple to perform and requires equipment usually already present in most practices such as a microscope and slides, cotton-tipped applicators and stains. Cytology interpretation is also easily self taught. With little practice the practitioner can easily become familiar with sample interpretation from inflammatory lesions; including recognition of bacteria, yeast, dermatophyte spores and hyphae, deeper fungal elements and parasites. Additionally, the practitioner should become familiar with the variety of inflammatory cells seen with these conditions, as well as keratinocyte morphology. This article provides an overview and the initial steps on how to become a more proficient cytologist in practice.

Cutaneous involvement by angioimmunoblastic T-cell lymphoma: a unique histologic presentation, mimicking an infectious etiology

Angioimmunoblastic T-cell lymphoma (AILT) is an aggressive peripheral T-cell lymphoma that is frequently accompanied by a cutaneous eruption. The cutaneous findings most commonly consist of a maculopapular eruption on the trunk. However, purpura, infiltrated or urticarial plaques, papulovesicular lesions, nodules, and erythroderma have also been reported. Histologic findings in the lymph node are characteristic, while those in the skin may show one of four patterns. Here, we review the previously reported histologic patterns and present a case of AILT involving the skin with a unique histologic appearance of necrotizing granulomas with abundant histiocytes and eosinophils, mimicking an infectious etiology.

Lichenoid and granulomatous dermatitis associated with atypical mycobacterium infections

BACKGROUND

Lichenoid and granulomatous dermatitis defines a distinctive pattern of cutaneous inflammation that may be part of the morphologic spectrum of idiopathic lichenoid reactions such as lichen planus and as well may be seen with lichenoid drug reactions, endogenous T-cell dyscrasias and as a feature of certain systemic diseases especially Crohn's disease and rheumatoid arthritis.

RESULTS

We encountered three cases of lichenoid and granulomatous dermatitis in which the basis was one of primary cutaneous Mycobacterium infection. In all three cases acid fast stains revealed pathogenic organisms and as well cultures were positive for Mycobacterium kansasii in one case and Mycobacterium marinum in another. Other features included a prominent perineural and periadnexal lymphocytic infiltrate.

CONCLUSIONS

The differential diagnosis of lichenoid and granulomatous dermatitis should also encompass primary cutaneous Mycobacterium infection in addition to the other more characteristic entities associated wtih this distinctive reaction pattern. Infection with Mycobacterium induces a TH1 dominant response which would hence produce an infiltrate.

[Necrotizing cutaneous infections and Fournier's gangrene]

Fournier's gangrene is a necrotizing infection of skin and soft tissue of the perineum. Several sources of contamination have been described: cutaneous, urological or anorectal. Anatomy of the perineum helps in the prediction of the extension of the infection. The bacterial flora (usually mixed aero-anaerobic flora) depends on the source of infection: gram-positive cocci (skin source) combined with gram-negative bacilli and anaerobes (urological or anorectal source). CT scan and echography are useful tools for the diagnosis without delaying surgery. In the diagnostic procedure and the management, proctological examination, retrograde uretrography, bowel and urine derivation should be discussed.