The Use of (1–3) β-Glucan Along with Itraconazole Against Canine Refractory Sporotrichosis

Sporotrichosis, caused by the Sporothrix schenckii fungal complex, is a zoonotic mycosis distributed worldwide. Itraconazole is the treatment of choice for domestic animals although some fungal isolates have shown resistance to this drug. The objective of this study was to report, for the first time, the use of (1–3) β-glucan along with itraconazole in the treatment of a canine with sporotrichosis caused by Sporothrix brasiliensis. The animal had ulcerated and crusted lesions, especially on the nasal planum. Clinical samples were collected for a complete blood count, cytological analysis of the lesion, and fungal culture. Based on the results of the laboratory examination, and after the fungal culture, antibiotic therapy and treatment with itraconazole were initiated. Two additional fungal cultures were performed, which were positive. After 7 months of the animal treatment with itraconazole, the S. brasiliensis culture was still positive, so that the itraconazole was associated with (1–3) β-glucan. After four weekly applications of glucan, the complete elimination of the fungus was observed based on the fungal culture negative results. The results show, therefore, that (1–3) β-glucan with itraconazole promoted the case resolution, and it may be considered a promising alternative for the treatment of sporotrichosis in cases of resistance to conventional therapy.     

Therapeutic treatment with scFv–PLGA nanoparticles decreases pulmonary fungal load in a murine model of paracoccidioidomycosis

Paracoccidioidomycosis (PCM) is a systemic mycosis with lymphatic dissemination that is caused by Paracoccidioides species. Treatment of PCM consists of chemotherapeutics such as itraconazole, trimethoprim, sulfamethoxazole or amphotericin B. However, several studies are aiming to develop therapeutic alternatives for the treatment of fungal infection using new molecules as adjuvants. The single-chain variable fragments (scFv) from an antibody that mimics the main fungal component incorporated within poly(lactide-co-glycolic) acid (PLGA) nanoparticles helped treat the fungal disease. After expressing the scFv in Picchia pastoris (P. pastoris), the recombinant molecules were coupled with PLGA, and the BALB/c mice were immunized before or after infection with yeast Paracoccidioides brasiliensis (P. brasiliensis). Our results showed decreased disease progression and decreased fungal burden. Taken together, our results showed an increased of IFN-γ and IL-12 cytokine production and an increased number of macrophages and dendritic cells in the pulmonary tissue of BALB/c mice treated with a high concentration of our molecule. Our data further confirm that the scFv plays an important role in the treatment of experimental PCM.     

How I Treat Histoplasmosis

Histoplasmosis is an endemic mycosis caused by the dimorphic fungus Histoplasma capsulatum. Some important manifestations of infection include acute or chronic pulmonary disease, histoplasmomas, progressive disseminated histoplasmosis, and central nervous system infection. Depending on the clinical presentation, site of infection and severity of disease, either amphotericin B preparations followed by itraconazole, or itraconazole alone have become the preferred treatments. Because prolonged therapy (6 weeks to 24 months) may be required, careful monitoring for nephrotoxicity in patients on amphotericin B preparations is necessary. In addition, in patients receiving itraconazole, vigilance for drug interactions and pharmacokinetic properties is warranted. Histoplasma antigen testing has improved rapidity of diagnosis and the ability of long-term monitoring for clinical response in patients with histoplasmosis.     

A Case of Relapsed Chromoblastomycosis Due to Fonsecaea monophora: Antifungal Susceptibility and Phylogenetic Analysis

Chromoblastomycosis is a chronic cutaneous and subcutaneous mycosis. The management of this infection continues to be challenging because there is no consensus on the therapeutic regimen. We report here a case of a 69-year-old male patient with cauliflower-like lesions on his left leg and foot. He had already been treated with itraconazole at a dose of 200 mg/day for 5 months, with mycological cure for all the affected areas. However, the lesions relapsed at both sites, and treatment with itraconazole was resumed at the dose previously used. Initially, direct mycological examination, cultural, and microculture slide observation were performed. Afterward, sequencing of the ITS1-5.8S rDNA-ITS2 region of the fungal DNA and evaluation of its susceptibility to antifungal agents alone and in combination were performed. In direct mycological examination, the presence of sclerotic cells was verified, and the fungus was identified as Fonsecaea based on cultural and microscopic examinations. Identification as Fonsecaea monophora was confirmed after sequencing of the ITS region and phylogenetic analysis. The isolate was susceptible to itraconazole and terbinafine. The combinations of amphotericin B and terbinafine and terbinafine and voriconazole were synergistic. The use of drugs for which the causative agent is susceptible to singly or in combination may be an alternative for the treatment of mycosis. Furthermore, the identification of the agent by molecular techniques is important for epidemiological purposes. To the best of our knowledge, this is the first case of relapsed chromoblastomycosis caused by F. monophora in Brazil.     

Systemic antifungals. Pharmacodynamics and pharmacokinetics

Invasive fungal infections are important causes of morbidity and mortality in critically ill non neutropenic patients. For many years, amphotericin B and flucytosine have been the only available antifungal agents for invasive fungal infections. Fortunately, the antifungal armamentarium has increased during the past two decades with the addition of several new agents. In addition to itraconazole and fluconazole, lipid formulations of amphotericin B, voriconazole, and caspofungin have been recently licensed. These various antifungal agents differ in their pharmacokinetic and pharmacodynamic profile.     

Allergic fungal rhinosinusitis caused by Curvularia sp.

Allergic fungal rhinosinusitis is a benign and non-invasive sinusal disease related to a hypersensitivity reaction to fungal antigens. This process can cause tissue edema with chronic inflammatory disturbances of the respiratory mucosa. We present the case of a 17 year-old immunocompetent male, with history of seasonal allergic rhinosinusitis, nasal polyps and previous surgery for mucocele of the frontal sinus. Sticky material was removed in the last surgery that revealed pigmented and septed filaments on direct examination, and yielded Curvularia on Sabouraud dextrose agar. After a course of amphotericin B, treatment was switched to itraconazole, with good tolerance and favorable clinical outcome.     

地塞米松影响念珠菌对抗真菌药物敏感性的实验研究

目的 探讨地塞米松在体外试验中是否影响念珠菌对抗真菌药物的敏感性,以了解糖皮质激素与抗真菌药物直接作用于念珠菌时是否存在相互作用。方法 用微量液体培养基稀释法分别测定26株白念珠菌与地塞米松（0．2mg／ml）共同孵育前、孵育24～48h及7d时氟康唑、伊曲康唑、两性霉素B的最低抑菌浓度（MIC）值,并作对照。结果 白念珠菌与地塞米松孵育24～48h后、孵育后第7d氟康唑和伊曲康唑的MIC值升高,分别与孵育前的MIC值存在统计学差异,但孵育24～48h后的MIC与孵育后第7d的MIC无统计学差异;白念珠菌与地塞米松共同孵育24～48h后两性霉素B的MIC值也较孵育前升高,但第7d的MIC值与孵育前无差异。结论 地塞米松可增加三种抗真菌药物对于白念珠菌的MIC,但三种抗真菌药物间存在差异,表明地塞米松对于氟康唑和伊曲康唑体外抗白念珠菌的活性有拮抗作用,但没有时间依赖性,地塞米松对于两性霉素B的影响较氟康唑和伊曲康唑小,且影响时间较短。     

Evaluation of Amphotericin B and Chloramphenicol as Alternative Drugs for Treatment of Chytridiomycosis and Their Impacts on Innate Skin Defenses

Chytridiomycosis, an amphibian skin disease caused by the emerging fungal pathogen Batrachochytrium dendrobatidis, has been implicated in catastrophic global amphibian declines. The result is an alarming decrease in amphibian diversity that is a great concern for the scientific community. Clinical trials testing potential antifungal drugs are needed to identify alternative treatments for amphibians infected with this pathogen. In this study, we quantified the MICs of chloramphenicol (800 μg/ml), amphotericin B (0.8 to 1.6 μg/ml), and itraconazole (Sporanox) (20 ng/ml) against B. dendrobatidis. Both chloramphenicol and amphotericin B significantly reduced B. dendrobatidis infection in naturally infected southern leopard frogs (Rana [Lithobates] sphenocephala), although neither drug was capable of complete fungal clearance. Long-term exposure of R. sphenocephala to these drugs did not inhibit antimicrobial peptide (AMP) synthesis, indicating that neither drug is detrimental to this important innate skin defense. However, we observed that chloramphenicol, but not amphotericin B or itraconazole, inhibited the growth of multiple R. sphenocephala skin bacterial isolates in vitro at concentrations below the MIC against B. dendrobatidis. These results indicate that treatment with chloramphenicol might dramatically alter the protective natural skin microbiome when used as an antifungal agent. This study represents the first examination of the effects of alternative antifungal drug treatments on amphibian innate skin defenses, a crucial step to validating these treatments for practical applications.     

两性霉素B联合伊曲康唑或卡泊芬净治疗恶性血液病并发侵袭性真菌感染

目的观察两性霉素B联合伊曲康唑或卡泊芬净治疗恶性血液病患者并发侵袭性真菌感染(IFI)的临床疗效及安全性。方法收集我院联合治疗患者9例,对其疗效及毒副反应进行分析研究。结果9例患者7例有效,1例无效,1例停药。低钾是最常见的副反应,其他副反应包括畏寒、发热及肝、肾功能受损。结论两性霉素B联合伊曲康唑或卡泊芬净治疗IFI,经济、有效,患者依从性较好。     

重症监护病房白念珠菌耐药性8年变化趋势

目的调查上海长征医院重症监护室(ICU)近8 a中临床分离白念珠菌的耐药性变化,为临床治疗提供参考。方法上海长征医院ICU 2002～2009年从414例患者中首次分离出414株白念珠菌,对其中277株进行药敏试验。采用Cox-Stuart趋势检验回顾性分析临床分离真菌中白念珠菌所占比例变化趋势和白念珠菌对常用抗真菌药物耐药率的变化趋势。结果 2002～2009年间,上海长征医院ICU白念珠菌分离株数从2002年的34株增加至2009年的92株,但白念珠菌占总真菌分离株数的百分比维持在34.6%～55.7%,P=0.03。白念珠菌对于5-氟胞嘧啶和两性霉素B平均耐药率分别为4.0%和0.7%,对其他常用抗真菌药的耐药率依次为咪康唑47.0%、酮康唑10.8%、伊曲康唑19.9%、特比萘芬42.6%、氟康唑14.6%及伏立康唑13.0%。白念珠菌对5-氟胞嘧啶和两性霉素B和伊曲康唑耐药率的8年变化无统计学差异。结论上海长征医院ICU近8 a来白念珠菌仍然为临床较为常见的真菌分离株,但白念珠菌占总分离株数的百分比有逐渐减少的趋势。白念珠菌对常用抗真菌药物耐药性均无明显变化趋势。     

Aerosolized Delivery of Antifungal Agents

Pulmonary infections caused by Aspergillus species are associated with significant morbidity and mortality in immunocompromised patients. Although the treatment of pulmonary fungal infections requires the use of systemic agents, aerosolized delivery is an attractive option in prevention because the drug can concentrate locally at the site of infection with minimal systemic exposure. Current clinical evidence for the use of aerosolized delivery in preventing fungal infections is limited to amphotericin B products, although itraconazole, voriconazole, and caspofungin are under investigation. Based on conflicting results from clinical trials that evaluated various amphotericin B formulations, the routine use of aerosolized delivery cannot be recommended. Further research with well-designed clinical trials is necessary to elucidate the therapeutic role and risks associated with aerosolized delivery of antifungal agents. This article provides an overview of aerosolized delivery systems, the intrapulmonary pharmacokinetic properties of aerosolized antifungal agents, and key findings from clinical studies.     

The Management of Chronic Pulmonary Aspergillosis: The UK National Aspergillosis Centre Approach

Purpose of Review

Chronic pulmonary aspergillosis (CPA) is a serious long-term fungal disease of the lung with a worldwide prevalence. Treatment of CPA is not straightforward given the often-multiple associated co-morbidities, complex clinical picture, drug interactions, toxicities and intolerances.

Recent Findings

First line treatment is oral itraconazole or voriconazole. In the event of intolerance or toxicity, patients may be swapped from itraconazole to voriconazole or vice versa. In the event of resistance or further intolerance, third line treatment with posaconazole could be initiated. In those with pan-azole resistance, short-term courses of intravenous liposomal amphotericin B or micafungin are fourth line therapy, keeping in mind the nephrotoxic effects of amphotericin B.

Summary

The available evidence for current treatments in CPA is limited and based mostly on retrospective cohort studies. There is a real need to raise awareness of this devastating disease to enable early treatment as well as prospective drug trials and studies to identify potential patient factors that correlate with progression, severity and overall outcomes in order to target future therapies.

     

Treatment of Blastomycosis

Blastomycosis, disease caused by the thermally dimorphic fungus Blastomyces dermatitidis, occurs predominantly in the Midwest, south central, and northeastern United States. Spores from the environment are inhaled into the lungs where they may cause subclinical infection, acute or chronic pneumonia, or disseminated disease. The Infectious Diseases Society of America has recently published updated guidelines on the management of blastomycosis. Antifungal therapies that have proven effective for blastomycosis include itraconazole and amphotericin B. The lipid formulations of amphotericin B are preferred owing to reduced nephrotoxicity, especially when prolonged intravenous therapy is necessary. The more recently approved triazole voriconazole may play a greater role in treating blastomycosis, especially central nervous system disease, as more clinical data become available.     

The Current Role of Posaconazole in Managing Zygomycosis

Zygomycosis is an emerging fungal disease that is associated with considerable excess morbidity and mortality. Standard approaches to treatment include reversal of the underlying immunodeficiency or metabolic disorder, surgical interventions, and antifungal therapy with amphotericin B lipid complex or liposomal amphotericin B. Among the newer triazoles, posaconazole possesses activity in vitro and in experimental animal models of zygomycosis, and two observational case series have demonstrated promising clinical responses in the salvage setting. This article reviews the current body of preclinical and clinical data and assesses the present and potential future role of posaconazole in managing zygomycosis.     

Blastomyces dermatitidis produces melanin in vitro and during infection

Melanin is made by several important pathogenic fungi and is implicated in the pathogenesis of a number of mycoses. This study investigates whether the thermally dimorphic fungal pathogen Blastomyces dermatitidis produces melanin. Using techniques developed to study melanization in other fungi, we demonstrate that B. dermatitidis conidia and yeast produce melanin in vitro and that yeast cells synthesize melanin or melanin-like pigment in vivo. Melanization reduced susceptibility to amphotericin B, but not to itraconazole or voriconazole. Since melanin is an important virulence factor in other pathogenic fungi, this pigment may affect the pathogenesis of blastomycosis.     

Meta-analysis of prophylactic or empirical antifungal treatment versus placebo or no treatment in patients with cancer complicated by neutropenia.

OBJECTIVE: To determine whether antifungal agents given prophylactically or empirically decrease morbidity and mortality in patients with cancer complicated by neutropenia. DESIGN: Meta-analysis of randomised trials of amphotericin B, various lipid soluble formulations of amphotericin B (for example, AmBisome), fluconazole, ketoconazole, miconazole, or itraconazole compared with placebo or no treatment. SETTING: Trials conducted anywhere in the world. SUBJECTS: Patients with cancer complicated by neutropenia. MAIN OUTCOME MEASURES: Mortality, invasive fungal infection (defined as positive blood culture, oesophageal candidiasis, or lung or deep tissue infection), and colonisation. RESULTS: 24 trials with 2758 randomised patients were reviewed; the total number of deaths was 434. Prophylactic or empirical treatment with antifungals as a group bad no effect on mortality (odds ratio 0.92; 95% confidence interval 0.74 to 1.14). Amphotericin B decreased mortality significantly (0.58; 0.37 to 0.93) but the studies were small and the difference in number of deaths was only 15. Antifungal treatment decreased the incidence of invasive fungal infection (0.47; 0.35 to 0.64) and fungal colonisation (0.45; 0.30 to 0.69). For every 73 patients treated (95% confidence interval to 48 to 158) one case of fungal invasion was prevented in surviving patients. CONCLUSIONS: There seems to be no survival benefit of antifungal agents given prophylactically or empirically to patients with cancer complicated by neutropenia. These agents should be restricted to patients with proved infection and those in randomised trials. A large, definitive placebo controlled trial of amphotericin B is needed.     

Paracoccidioidomycosis

Paracoccidioidomycosis is the most frequent endemic mycosis in South America. The infection is more prevalent in rural workers, and recent epidemiologic data suggest that changes in agricultural practices (such as a decrease in coffee plantations and an increase in sugar cane plantations) may result in a reduction in the incidence of infection. After being inhaled, Paracoccidioides brasiliensis usually causes a benign and transient pulmonary infection that may progress to an acute form or, more frequently, reactivate later as a chronic disease. The diagnosis is usually made by direct examination and culture of clinical specimens; serologic tests may be of help, especially antigen detection. The drug of choice for the chronic form is oral itraconazole, whereas patients with more severe forms may be treated with intravenous amphotericin B or sulfamethoxazoletrimethoprim. The newer azole voriconazole is also effective, and it may be a good alternative because it can be given by oral or intravenous route.     

In vitro susceptibility of dematiaceous fungi to ten antifungal drugs using an agar diffusion test

We assessed the usefulness of an agar diffusion method, NeoSensitabs, to determine in vitro sensitivity of 52 isolates of dematiaceous filamentous fungi against ten antifungal agents: amphotericin B, 5-fluorocytosine, ketoconazole, fluconazole, itraconazole, terbinafine, bifonazole, miconazole, clotrimazole, and griseofulvin. For the preparation of the inoculum, a spectrophotometric method including both Shadomy and Casitone agar (CAS) culture media was used. Dematiaceous filamentous fungi were sensitive to itraconazole, terbinafine and bifonazole. Ketoconazole (90.4%), miconazole (71%), and clotrimazole (46%) showed a variable susceptibility pattern. Most species were resistant to griseofulvin and fluconazole (96%). All isolates were resistant to 5-fluorocytosine. Sixty-three percent of strains were susceptible to amphotericin B and 28.8% resistant. Inhibition zones in the antifungal susceptibility testing did not vary according to culture medium, although fungal growth was better in CAS. Variations in antifungal sensitivity in Exophiala spinifera and Fonsecaea pedrosoi spp. would justify an in vitro susceptibility study when indicating antifungal therapy. These results show that NeoSensitabs agar diffusion method is simple, rapid, and low-cost and can be available to many clinical laboratories for the study of in vitro sensitivity of dematiceous moulds.     

Treatment of disseminated histoplasmosis in hamsters

A comparative study between itraconazole, ketoconazole and amphotericin B in the treatment of experimental histoplasmosis in hamsters was carried out.Seventy five animals were inoculated intracardiacally with the yeast-phase of Histoplasma capsulatum. They were divided in 5 groups: 1) treated with itraconazole by gavage (g) at a daily dose of 16 mg/kg; 2) treated with ketoconazole by (g) at a daily dose of 80 mg/kg; 3) treated with amphotericin B intraperitoneally (i.p.) at 6 mg/kg every other day; 4) control animals receiving distilled water i.p. and 5) control animals receiving P.E.G. 200 by (g). All the treatments were started one week after the challenge inoculation and they were given for 21 days. The results were evaluated by autopsy of all the animals one week after the end of the treatments. The following determinations were taken into account: microscopic examinations of spleen, liver and lungs and cultures of the spleen with determination of colony forming units/g.All the antifungal drugs used in this study were able to cause negative microscopic examinations of the liver, spleen and lungs; but only amphotericin B produced culture negative results. Itraconazole and ketoconazole presented 66% and 86% of positive cultures respectively, nevertheless the C.F.U. were lower than those obtained in control groups.In these experimental conditions amphotericin B seems to be more active than the azolic compounds and itraconazole is slightly superior to ketoconazole at a lower dose.     

Molecular Identification and Antifungal Susceptibilities of Black Aspergillus Isolates from Otomycosis Cases in Hungary

Otomycosis, also known as fungal otitis externa, has been used to describe a fungal infection of the external auditory canal, but sometimes involving the middle ear. Many fungal species have been identified as infectious agents in otomycosis, with Aspergillus and Candida species being the most common. Among aspergilli, Aspergillus niger is the most commonly described species in the literature. In this study, 14 black Aspergillus strains were analyzed, which were isolated from otomycosis cases in Hungary between 2010 and 2011. These strains were identified as A. niger according to conventional morphological methods. Species identification was based on sequencing of part of the calmodulin gene. Our results indicate that instead of A. niger, A. awamori and A. tubingensis are the predominant species that cause ear infections in Southern Hungary. Antifungal susceptibility tests were carried out against four antifungal drugs: amphotericin B, itraconazole, ketoconazole and terbinafine. All isolates were found to exhibit low in vitro MIC values to amphotericin B, terbinafine and itraconazole. However, the examined isolates exhibited high in vitro MIC values to ketoconazole.