Cutaneous Fungal Infections in the Oncology Patient

There are two main types of fungal infections in the oncology patient: primary cutaneous fungal infections and cutaneous manifestations of fungemia. The main risk factor for all types of fungal infections in the oncology patient is prolonged and severe neutropenia; this is especially true for disseminated fungal infections. Severe neutropenia occurs most often in leukemia and lymphoma patients exposed to high-dose chemotherapy. Fungal infections in cancer patients can be further divided into five groups: (i) superficial dermatophyte infections with little potential for dissemination; (ii) superficial candidiasis; (iii) opportunistic fungal skin infections with distinct potential for dissemination; (iv) fungal sinusitis with cutaneous extension; and (v) cutaneous manifestations of disseminated fungal infections. In the oncology population, dermatophyte infections (i) and superficial candidiasis (ii) have similar presentations to those seen in the immunocompetent host. Primary cutaneous mold infections (iii) are especially caused by Aspergillus, Fusarium, Mucor, and Rhizopus spp. These infections may invade deeper tissues and cause disseminated fungal infections in the neutropenic host. Primary cutaneous mold infections are treated with systemic antifungal therapy and sometimes with debridement. The role of debridement in the severely neutropenic patient is unclear. In some patients with an invasive fungal sinusitis (iv) there may be direct extension to the overlying skin, causing a fungal cellulitis of the face. Aspergillus, Rhizopus, and Mucor spp. are the most common causes. We also describe the cutaneous manifestations of disseminated fungal infections (v). These infections usually occur in the setting of prolonged neutropenia. The most common causes are Candida, Aspergillus, and Fusarium spp. Therapy is with systemic antifungal therapy. The relative efficacies of amphotericin B, fluconazole, itraconazole, voriconazole, and caspofungin are discussed. Recovery from disseminated fungal infections is unlikely, however, unless the patient's neutropenia resolves.     

Therapy of common superficial fungal infections

Superficial fungal infections are common, especially onychomycosis, dermatophytoses, and superficial Candida infections. Most superficial fungal infections are treated with topical antifungal agents unless the infection covers an extensive area or is resistant to initial therapy. Onychomycosis often requires systemic therapy with griseofulvin, itraconazole, or terbinafine. The objective of this review is to provide the practicing dermatologist with the recommended available therapy for the treatment of common superficial fungal infections.     

白细胞介素17相关生物制剂治疗银屑病过程中浅部真菌感染的发生及应对策略

本文综述白细胞介素（IL）-17与皮肤黏膜真菌感染易感性的基本机制,以及与IL-17相关的生物制剂,如司库奇尤单抗、依奇珠单抗、布罗达单抗、拜莫克珠单抗和乌司奴单抗在治疗银屑病中发生的浅部真菌感染。与IL-17相关生物制剂治疗相关的浅部真菌感染以轻度或中度为主,多呈局限性,且抗真菌治疗效果良好。此外,本文介绍了对相关浅...     

Fungal infections in children

Fungal infections of the skin represent a relatively common problem in pediatric dermatology. Although fungal infections of the feet, nails, and groin are uncommon in the pediatric age group, fungal infections of the scalp are very common and must be diagnosed early because they may lead to permanent hair loss if left untreated. Perhaps the most significant change in fungal infections in children has occurred in tinea capitis, including the causative agent and the type of infection this organism may produce; these factors are focused upon in this article. Also discussed are infections caused by the yeast organisms Candida albicans and Pityrosporum orbiculare, as well as the deep mycoses, specifically chromoblastomycosis and cutaneous aspergillosis.     

Candida infections today--how big is the problem?

Thirty years ago, superficial fungal infections were common, but systemic fungal infections were not as frequent as today. Since that time incidence in both superficial and systemic fungal infection has been increasing. The reasons are many. Due to advances in medicine, human life span is extended and many people suffer from various immunodeficiencies. Transplantation of organs and tissues, wide application of parenteral feeding and parenteral administration of drugs, infection with human immunodeficiency virus (HIV), and long-term peroral administration of antibiotics are the main reasons for appearance of many immunologic dysfunctions and thereby systemic fungal infections. The most usual predisposing factors for systemic fungal infection are skin and mucosal damage, hypofunction of T-cell-mediated immunity, decreased function of neutrophiles, long-term administration of corticosteroids, as well as dysfunction of microbial flora. Systemic fungal infections are a great problem, because they are very difficult to prove and to treat. This is why prevention of systemic infections is extremely important today, including the removal of predisposing factors as well as rational drug administration.     

皮肤真菌感染中的免疫应答

由于各种众所周知的原因,导致免疫功能低下的患者不断增多,真菌感染率逐年攀升,而大多数关于真菌病的免疫学研究多局限于深部真菌感染。针对不同的皮肤真菌感染,对侵犯皮肤的真菌抗原性和机体对病原体的免疫应答加以介绍,并解释了脂溢性皮炎和特应性皮炎与真菌感染的关系。     

Widespread and invasive Trichophyton rubrum infection mimicking Kaposi's sarcoma in a patient with AIDS

Opportunistic fungal infections are commonly encountered in AIDS patients. Candidiasis, tinea pedis, onychomycosis, and deep mycotic infections have been the fungal infections most frequently reported in these patients. Dermatophyte infections can appear to be atypical and aggressive in these patients and may lead to a misdiagnosis. We report a Trichophyton rubrum infection in a 44-year-old man with AIDS that presented as a widespread and multiple tumor-like appearance. After the patient was treated with terbinafine for 21 weeks, the lesions cleared completely. We think that this type of dermatophyte infection is very unusual in patients with AIDS and could lead to inappropriate diagnostic processes and treatments.     

The complex role of mast cells in fungal infections

In addition to their critical role in allergic disorders, mast cells (MCs) are well recognized for their protective effector functions during bacteria and parasite infections. This review describes recent advancements of our understanding of the complex role of MCs in fungal infections. Specifically, we outline key features of the contribution of MCs to infections with six fungal pathogens, namely Sporothrix, Paracoccidioides, Aspergillus, Malassezia, Candida and Dermatophytes. Evidence from studies of these pathogens suggests that MCs can function as positive regulators that detect and contain fungi at the site of infection. However, it appears that the inflammation induced by MCs following fungal infections may not always and only be beneficial to the host. MC responses during fungal infections may primarily benefit the pathogen by facilitating its spreading and contributing to a greater severity of fungal infections. This review also highlights key drivers of MCs activation and effector mechanisms that have been identified for the multidimensional function of MCs in fungal diseases and in allergic diseases combined with fungal infection.     

Advances in topical and systemic antifungals

Topical antifungal agents are generally used for the treatment of superficial fungal infections unless the infection is widespread, involves an extensive area, or is resistant to initial therapy. Systemic antifungals are often reserved for the treatment of onychomycosis, tinea capitis, superficial and systemic candidiasis, and prophylaxis and treatment of invasive fungal infections. With the development of resistant fungi strains and the increased incidence of life-threatening invasive fungal infections in immunocompromised patients, some previously effective traditional antifungal agents are subject to limitations including multidrug interactions, severe adverse effects, and their fungistatic mechanism of actions. Several new antifungal agents have demonstrated significant therapeutic benefits and have broadened clinicians' choices in the treatment of superficial and systemic invasive fungal infections.     

I TINEA CORPORIS

In Western Australia, a total of 2.259 scrapings from the glabrous skin grew a fungal pathogen in the 10-year period 1963–1972. The dermatophyte most frequently isolated from these lesions was Microsporum canis, followed by Trichophyton rubrum, Trichophyton mentagrophytes and Trichophyton tonsurans, in this order. Candida was responsible for only 6.3% of the infections and is not an important causal agent in infections of the glabrous skin. The majority of fungal infections occur in the 1–10 age group, 46.17% of the total; but infections occur in all age groups from a few weeks old babies to octogenarians. Total frequency of infection in males and females is equal but variations in numbers are seen to occur within different species. Although monthly variations in numbers of infections occur, infection is present in the community in all seasons.     

The risk of deep fungal infections during biologic therapy for psoriasis

With a growing understanding of the pathogenesis and immunological basis of psoriasis, the medical community has seen the development of more focused biological treatment options for patients suffering from the disease, which are beginning to revolutionize the treatment of psoriasis. It is already well known that certain biologics are associated with an increased risk of reactivating tuberculosis in patients with latent disease, however, with increasing use of biologic agents across indications, there has also been a rise in reports of associated deep fungal infections. The mechanism of action of these biologic anti‐psoriatic therapies allows physicians to address the underlying cause of patients' symptoms. The question though, is whether this same therapeutic mechanism may predispose patients to serious infections, including deep fungal infections.     

Periorbicular trichophyton verrucosum infections]

Three patients with periorbicular infections by Trichophyton verrucosum are described. This type of fungal infection is much less common as compared to the usual kerion formation. The main characteristics of Trichophyton verrucosum and of the epidemiology and clinical course of infections with Trichophyton verrucosum are summarized. In this condition the identification of the causative agent as well as the therapeutic regimen chosen to eliminate fungal growth deserve careful attention.     

Opportunistic fungal infections in immunocompromised hosts

Fungal infections in immunocompromised hosts cause major morbidity and mortality. The Candida and Aspergillus species are the most common causes, but many rarer organisms, once considered "contaminants," are being reported. The number of patients who receive immunosuppressive agents for the treatment of malignancy or for organ transplantation is increasing as well as the potential for local or disseminated fungal infections. The diagnosis of these infections is often difficult and the existing methods for treatment are often ineffective. A high degree of suspicion to identify fungal infections and to prompt initiation of treatment must be maintained if the survival rate of these patients is expected to improve.     

The clinical significance of fungi in atopic dermatitis

Atopic dermatitis (AD) is one of the most common chronic inflammatory skin diseases and is caused by multiple factors including genetic factors, skin barrier defects, host immune responses, allergen sensitivity, environmental effects, and infections. Commonly, bacterial and viral infections are present in the eczematous lesions of AD patients and clearly aggravate the symptoms. However, studies of fungal infections in AD are limited in spite of the fact that there are reports showing that Malassezia, Candida, and some dermatophytes can affect the symptoms of AD. Moreover, certain fungal infections are sometimes overlooked and need to be considered particularly in AD patients with treatment failure as clinical features of those fungal infections could mimic eczematous lesions in AD. Here, we review the epidemiology, pathogenesis, clinical manifestations, and overlooked features of fungal infections associated with the symptoms of AD including the diagnosis and effectiveness of fungal treatments in AD patients.     

院内深部真菌感染的调查

目的了解昆明医学院第二附属医院2007年6月至12月期间院内深部真菌感染的状况。方法对目标时间内住院病人送检标本,进行真菌检查、鉴定和药敏实验;对检出真菌的病例进行临床资料的调查分析。结果调查期间共收到标本l313例,真菌培养阳性213例,其中白假丝酵母菌124例,68．55％,白假丝酵母菌对氟康唑敏感。临床资料显示：主要感染部位是呼吸系统;主要相关因素是使用广谱抗生素和激素;白假丝酵母菌是主要病原菌。结论2007年6月至12月期间昆明医学院第二附属医院院内真菌感染阳性检出率为16．22％;68．55％,白假丝酵母菌是主要的病原菌对氟康唑敏感。主要感染部位是呼吸系统;主要相关因素是使用广谱抗生素和激素;白假丝酵母菌是主要病因原菌。     

侵袭性丝状真菌感染的流行病学趋势

随着感染真菌高危人群的增多,丝状真菌引起的侵袭性感染亦日益增多.虽然烟曲霉是最常见的病原菌,但非烟曲曲霉(如土曲霉)以及非曲霉丝状真菌(如镰刀霉属,赛多孢霉属及接合菌)也已经成为重要的感染因素.这些菌种对两性霉素B或其他常用的抗真菌药物天然耐药或不敏感,在临床上常导致较高的病死率.概述侵袭性丝状真菌感染的流行病学研究现状,旨在强调早期病原学诊断和选择敏感抗真菌药物的临床意义.

Abstract：

The prevalence of invasive filamentous fungal infections has been rising with the increase of high-risk population. Although Aspergillus fumigatus remains the most frequent cause of these infections, nonfumigatus Aspergillus species such as Aspergillus terreus and non-Aspergillus filamentous fungi such as Fusarium species, Scedosporium species and Zygomycetes have emerged as important pathogens. These fungal species are inherently resistant or less susceptible to amphotericin B or other antifungal drugs, and often cause a high mortality in patients. The epidemiology of invasive filamentous fungal infections is reviewed here to emphasize the clinical importance of early pathogenic diagnosis and selection of active antifungal agents.     

Superficial fungal infections in 102 renal transplant recipients: a case-control study

BACKGROUND: Renal transplant recipients are predisposed to superficial fungal infections caused by graft-preserving immunosuppressive therapy. Reports have documented a wide range of prevalence rates for superficial fungal infections in this patient group. OBJECTIVE: The aim of this study was to determine the prevalence and clinical and mycological features of superficial fungal infections in renal transplant recipients at our center. METHODS: One hundred two consecutively registered renal transplant recipients (34 women, 68 men) and 88 healthy age- and sex-matched persons acting as controls (30 women, 58 men) underwent screening for the presence of superficial fungal infection. Skin scrapings and swabs were obtained from the dorsum of the tongue, upper part of the back, toe webs, and any suspicious lesions. Nail clippings were also collected. All samples were examined by direct microscopy and were stained with calcofluor white. The samples were cultured in Sabouraud dextrose agar, mycobiotic agar, and dermatophyte test medium. Candida species were identified on the basis of germ-tube production, spore formation in cornmeal agar, and results of biochemical testing. Dermatophytes were identified on the basis of colonial and microscopic morphologic features in conjunction with results of physiologic evaluation (in vitro hair perforation test, urease activity, temperature tolerance test, and nutritional test). RESULTS: Sixty-five (63.7%) of the 102 renal transplant recipients had cutaneous-oral candidiasis, dermatophytosis, or pityriasis versicolor, whereas only 27 (30.7%) of controls had fungal infection. Pityriasis versicolor was the most common fungal infection in the patient group (36.3%), followed by cutaneous-oral candidiasis (25.5%), onychomycosis (12.7%), and fungal toe-web infection (11.8%). Pityriasis versicolor and oral candidiasis were significantly more common among the renal transplant recipients, whereas the frequency of dermatophytosis in patients and controls was similar. Candida albicans was the main agent responsible for oral candidiasis, and Trichophyton rubrum was the most common dermatophyte isolated. Analysis showed that age, sex, and duration of immunosuppression did not significantly affect the prevalence of superficial fungal infection. Cyclosporine treatment and azathioprine therapy were identified as independent risk factors for superficial fungal disease. CONCLUSIONS: The prevalence of opportunistic infections with Pityrosporum ovale and C albicans is increased among renal transplant recipients, probably owing to the immunosuppressed state of this patient population. However, renal transplant recipients are not at increased risk of dermatophytosis.     

Cutaneous Fungal Infection in a Neonatal Intensive Care Unit Patient: A Case Report and Literature Review

Fungal skin infections are not uncommon in healthy, premature or immunocompromised newborns. Healthy neonates usually develop fungal skin infections caused by dermatophytes, Candida and Malassezia species, whereas immunocompromised neonates are more susceptible to skin infections with opportunistic pathogens (Aspergilus, Zygomycetes). Therefore neonatal fungal skin infections can range from generally benign superficial lesions to potentially fatal, deep, necrotic forms with dissemination. We present the case of a premature neonate twin with cutaneous fungal infection in a neonatal intensive care unit. Because there were doubts concerning the correspondence of the clinical features with the cultured species in the newborn, a literature review was performed searching for similar clinical cases.