Liposomal amphotericin B: what is its role in 2008?

Aspergillus fumigatus escape mechanisms from its harsh survival environments

Aspergillus fumigatus is a ubiquitous pathogenic mold and causes several diseases, including mycotoxicosis, allergic reactions, and systemic diseases (invasive aspergillosis), with high mortality rates. In its ecological niche, the fungus has evolved and mastered many reply strategies to resist and survive against negative threats, including harsh environmental stress and deficiency of essential nutrients from natural environments, immunity responses and drug treatments in host, and competition from symbiotic microorganisms. Hence, treating A. fumigatus infection is a growing challenge. In this review, we summarized A. fumigatus reply strategies and escape mechanisms and clarified the main competitive or symbiotic relationships between A. fumigatus, viruses, bacteria, or fungi in host microecology. Additionally, we discussed the contemporary drug repertoire used to treat A. fumigatus and the latest evidence of potential resistance mechanisms. This review provides valuable knowledge which will stimulate further investigations and clinical applications for treating and preventing A. fumigatus infections. KEY POINTS: • Harsh living environment was a great challenge for A. fumigatus survival. • A. fumigatus has evolved multiple strategies to escape host immune responses. • A. fumigatus withstands antifungal drugs via intrinsic escape mechanisms.

Evaluation of the pharmacokinetics of liposomal amphotericin B and analysis of the relationship between pharmacokinetics, efficacy and safety in patients with hematological diseases

INTRODUCTION

This study aimed to identify factors responsible for changes in blood concentrations of a liposomal formulation of amphotericin B (AMPH-B, L-AMB) and analyze the relationships between blood concentrations and efficacy or toxicity.

METHODS

L-AMB was administered to 30 patients being treated for hematological diseases. AMPH-B plasma concentrations were determined right before the initiation (Cmin) and at the end (Cmax) of infusion on at least 1 day, beginning on Day 3 of L-AMB treatment. The relationships of Cmin divided by dose (C/D ratio) to body weight, age, hepatic function, renal function, serum albumin, C-reactive protein (CRP), response, hypokalemia, and renal impairment were evaluated.

RESULTS

C/D ratio was not correlated with age, hepatic function, renal function, or serum albumin. Body weight adjusted C/D ratio was negatively correlated with CRP. Cmax and Cmin were compared between responders and non-responders, those with or without hypokalemia, and those with or without renal impairment. A higher Cmax in patients with hypokalemia was the only significant difference seen.

CONCLUSIONS

The negative correlation between CRP and plasma concentrations was likely caused by higher distribution of L-AMB from the blood to infected tissue in patients with a greater degree of infection, with a resulting decrease in plasma concentrations. AMPH-B plasma concentrations were not related to response. Higher Cmax of AMPH-B were observed in patients with hypokalemia, but no relationship between plasma concentration and renal toxicity was observed, suggesting that AMPH-B plasma concentrations appear to be minimally related to PD when used as L-AMB.

A systematic review and meta-analysis of efficacy and safety of isavuconazole for the treatment and prophylaxis of invasive fungal infections

BACKGROUND

Isavuconazole is a novel triazole antifungal agent. However, the previous outcomes were highlighted by statistical heterogeneity. This meta-analysis aimed to validate the efficacy and safety of isavuconazole for the treatment and prophylaxis of invasive fungal infections (IFIs) compared with other antifungal agents (amphotericin B, voriconazole and posaconazole).

METHODS

Scopus, EMBASE, PubMed, CINAHL and Ichushi databases were searched for relevant articles that met the inclusion criteria through February 2023. Mortality, IFI rate, discontinuation rate of antifungal therapy and incidence of abnormal hepatic function were evaluated. The discontinuation rate was defined as the percentage of therapy discontinuations due to adverse events. The control group included patients who received other antifungal agents.

RESULTS

Of the 1784 citations identified for screening, 10 studies with an overall total of 3037 patients enrolled. Isavuconazole was comparable with the control group in mortality and IFI rate in the treatment and prophylaxis of IFIs, respectively (mortality, odds rate (OR) 1.11, 95% confidential interval (CI) 0.82-1.51; IFI rate, OR 1.02, 95% CI 0.49-2.12). Isavuconazole significantly reduced the discontinuation rate in the treatment (OR 1.96, 95% CI 1.26-3.07) and incidence of hepatic function abnormalities in the treatment and prophylaxis, compared with the control group (treatment, OR 2.31, 95% CI 1.41-3.78; prophylaxis, OR 3.63, 95% CI 1.31-10.05).

CONCLUSIONS

Our meta-analysis revealed that isavuconazole was not inferior to other antifungal agents for the treatment and prophylaxis of IFIs, with substantially fewer drug-associated adverse events and discontinuations. Our findings support the use of isavuconazole as the primary treatment and prophylaxis for IFIs.

Diagnosis and Management of Invasive Candida Infections in Critically Ill Patients

Invasive candidiasis (IC) has become a serious problem in the intensive care unit patients with an attributable mortality rate that can reach up to 51%. Multiple global surveillance studies have shown an increasing incidence of candidemia. Despite their limited sensitivity (21-71%), cultures remain the gold standard for the diagnosis of IC associated with candidemia. Many adjunct laboratory tests exist to support or rule out the diagnosis, each with its indications and limitations, including procalcitonin, 1,3-β-D-glucan, mannan and anti-mannan antibodies, and Candida albicans germ tube antibody. In addition, polymerase chain reaction-based methods could expedite species identification in positive blood cultures, helping in guiding early empirical antifungal therapy. The management of IC in critically ill patients can be classified into prophylactic, preemptive, empiric, and directed/targeted therapy of a documented infection. There is no consensus concerning the benefit of prophylactic therapy in critically ill patients. While early initiation of appropriate therapy in confirmed IC is an important determinant of survival, the selection of candidates and drug of choice for empirical systemic antifungal therapy is more controversial. The choice of antifungal agents is determined by many factors, including the host, the site of infection, the species of the isolated Candida, and its susceptibility profile. Echinocandins are considered initial first-line therapy agents. Due to the conflicting results of the various studies on the benefit of preemptive therapy for critically ill patients and the lack of robust evidence, the Infectious Diseases Society of America (IDSA) omitted this category from its updated guidelines and the European Society of Intensive Care Medicine (ESICM) and the Critically Ill Patients Study Group of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) do not recommend it.

Cutaneous Mucormycosis After Elective Outpatient Gastrocnemius Recession for Plantar Fasciitis in an Immunocompetent Host: A Case Report

CASE

A healthy 21-year-old man underwent an elective gastrocnemius recession for plantar fasciitis. At 10 days postoperatively, he developed a severe limb-threatening cutaneous mucormycotic infection that led to multiple debridements and eventual skin grafting.

CONCLUSION

Cutaneous mucormycosis is a rare but severe fungal infection. Early recognition, deep surgical biopsy for diagnosis, and aggressive treatment with frequent thorough surgical debridements and antifungal pharmacotherapy are necessary. Although mucormycosis is more frequently seen in the immunocompromised host, it can occur in the immunocompetent patient most commonly after trauma. If not aggressively treated, it can be limb and life threatening.

Deoxycholate amphotericin for histoplasmosis in a patient with poor kidney function

A 48-year-old male patient living with HIV presented to our hospital with fever and weight loss. On evaluation, he was found to have pancytopenia, deranged liver and kidney function. CD4 count was 13 cells/uL. Bone marrow examination done because of pancytopenia showed yeast forms of histoplasmosis. Although liposomal amphotericin B is preferred for induction, he was treated with deoxycholate amphotericin B despite poor kidney function because of financial constraints. He was treated for 12 days with intravenous amphotericin, during which his clinical condition significantly improved. He was discharged on oral itraconazole.

Amphotericin B from antifungal to antiviral therapy: promising modern therapeutic branch

Introduction: Amphotericin B (AmB) which belongs to the polyene group has a wide spectrum in vitro and in vivo antimicrobial activity against fungi and parasites, but resistance to AmB is rare despite extensive use.

Material and methods: Atotal of 2530 articles were investigated in PubMed (n = 1525), Medline (n = 705), and Google Scholar (n = 300). From 2530 articles, only 61 studies were included in this review. All the short and full articles were searched that were scheduled to be published until April 2020.

Results: After its discovery, AmB has been one of the most common first-line choices in treating systemic fungal infection for over seven decades from its discovery. Recently, some studies have focused on the potential antimicrobial action of AmB against some enveloped and non-enveloped viruses, such as human immunodeficiency virus, Japanese encephalitis virus, herpes simplex virus, and Rubella virus.

Discussion: Among the invading pathogens, viruses constitute the most common ones,Due to the continuous spreading of viral infections with the rise in death numbers, new therapeutics development is urgent, as in general, some lethal viruses have no specific antiviral drugs or vaccines. So, this review may serve as an impetus for researchers working in the field of medical microbiology, vaccination, and antiviral drug design by discussing the most recent information about the antiviral action of AmB, as well as trying to provide a deeper understanding of major properties, mechanisms of action, immune system responses, and antimicrobial efficiency of AmB.

Conclusion: Since AmB is expected to alter the structure of the viral envelope, membrane integrity of cells, and internal cellular organelles, besides its other unique properties, such as host immunomodulatory effects, this review suggested that AmB as an effective anti-fungi drug may hold the promise of formulating a novel therapeutic option to treat many dangerous viruses, including those for treating which there are no active drugs or vaccines.

Amphotericin B as antiviral drug: Possible efficacy against COVID-19

Since its discovery, amphotericin B (AmB) is still one of the most common first-line choices in treatment pulmonary mycoses for over seventh decades from discovery. AmB which is belonged to the polyene group has a wide spectrum in vitro and in vivo antimicrobial activity against fungi and parasites, resistance to AmB is rare despite extensive use. Recently, some studies focused on the potential antimicrobial action of AmB against some enveloped viruses such as human immunodeficiency virus, Japanese encephalitis virus, and rubella virus. Coronaviruses are enveloped positive-sense RNA nucleic acid viruses that have club-like spikes, characterized by a distinctive replication strategy; they are round and sometimes pleomorphic shapes. COVID-19 is regarding the new genera of coronaviridae that appear the first time in Wuhan, China, in early December 2019. Due to the continuous spreading of the novel COVID-19 with the exponential rise in death numbers, new therapeutic development is urgent, in general, there are no specific antiviral drugs or vaccines for 2019-novel coronavirus. Hence, this review may serve as an impetus for researchers working in the field of medical microbiology, vaccination, and antiviral drug design by discussion the most recent information about the antiviral action of AmB against COVID-19 infection as well as trying to a deep understanding of major properties, mechanisms of action, immune system responses, and antimicrobial efficiency of AmB. Since AmB is expected to alter the structure of the viral envelope, membrane integrity of cells, and internal cellular organelles, besides its other unique properties such as host immunomodulatory effects, so this review suggested that AmB as an effective anti-fungi drug thus may hold the promise of formulating a novel therapeutic option to treat COVID-19.

Pharmacodynamics of Isavuconazole for Invasive Mold Disease: Role of Galactomannan for Real-Time Monitoring of Therapeutic Response

Background.

The ability to make early therapeutic decisions when treating invasive aspergillosis using changes in biomarkers as a surrogate for therapeutic response could significantly improve patient outcome.

Methods.

Cox proportional hazards model and logistic regression were used to correlate early changes in galactomannan index (GMI) to mortality and overall response, respectively, from patients with positive baseline GMI (≥0.5) and serial GMI during treatment from a phase 3 clinical trial for the treatment of invasive mold disease. Pharmacokinetic/pharmacodynamic (PK/PD) analysis in patients with isavuconazole plasma concentrations was conducted to establish the exposure necessary for GMI negativity at the end of therapy.

Results.

The study included 158 patients overall and 78 isavuconazole patients in the PK/PD modeling. By day 7, GMI increases of >0.25 units from baseline (3/130 survivors; 9/28 who died) significantly increased the risk of death compared to those with no increase or increases <0.25 (hazard ratio, 9.766; 95% confidence interval [CI], 4.356–21.9; P < .0001). For each unit decrease by day 7 from baseline, the odds of successful therapy doubled (odds ratio, 2.154; 95% CI, 1.173–3.955). An area under the concentration-versus-time curve over half-maximal effective concentration (AUC:EC₅₀) of 108.6 is estimated to result in a negative GMI at the end of isavuconazole therapy.

Conclusions.

Early trends in GMI are highly predictive of patient outcome. GMI increases by day 7 could be considered in context of clinical signs to trigger changes in treatment, once validated. Our data suggest that this improves survival by 10-fold and positive outcome by 3-fold. These data have important implications for individualized therapy for patients and clinical trials.

Clinical Trials Registration.

NCT00412893.

Cryptococcal antigen screening by lay cadres using a rapid test at the point of care: A feasibility study in rural Lesotho

INTRODUCTION

Cryptococcal meningitis is one of the leading causes of death among people with HIV in Africa, primarily due to delayed presentation, poor availability and high cost of treatment. Routine cryptococcal antigen (CrAg) screening of patients with a CD4 count less than 100 cells/mm3, followed by pre-emptive therapy if positive, might reduce mortality in high prevalence settings. Using the cryptococcal antigen (CrAg) lateral flow assay (LFA), screening is possible at the point of care (POC). However, critical shortages of health staff may limit adoption. This study investigates the feasibility of lay counsellors conducting CrAg LFA screening in rural primary care clinics in Lesotho.

METHODS

From May 2014 to June 2015, individuals who tested positive for HIV were tested for CD4 count and those with CD4 <100 cells/mm3 were screened with CrAg LFA. All tests were performed by lay counsellors. CrAg-positive asymptomatic patients received fluconazole, while symptomatic patients were referred to hospital. Lay counsellors were trained and supervised by a laboratory technician and counsellor activity supervisor. Additionally, nurses and doctors were trained on CrAg screening and appropriate treatment.

RESULTS

During the study period, 1,388 people were newly diagnosed with HIV, of whom 129 (9%) presented with a CD4 count <100 cells/mm3. Of these, 128 (99%) were screened with CrAg LFA and 14/128 (11%) tested positive. Twelve of the 14 (86%) were asymptomatic, and received outpatient fluconazole. All commenced ART with a median time to initiation of 15.5 days [IQR: 14-22]. Of the asymptomatic patients, nine (75%) remained asymptomatic after a median time of 5 months [IQR; 3-6] of follow up. One (8%) became co-infected with tuberculosis and died and two were transferred out. The two patients with symptomatic cryptococcal meningitis (CM) were referred to hospital, where they later died.

CONCLUSIONS

CrAg LFA screening by lay counsellors followed by pre-emptive fluconazole treatment for asymptomatic cases, or referral to hospital for symptomatic cases, proved feasible. However, regular follow-up to ensure proper management of cryptococcal disease was needed. These early results support the wider use of CrAg LFA screening in remote primary care settings where upper cadres of healthcare staff may be in short supply.

Prognostic value of galactomannan: current evidence for monitoring response to antifungal therapy in patients with invasive aspergillosis

Galactomannan (GM) is a polysaccharide present in the cell wall of Aspergillus spp. that is released during growth of the organism. It has been successfully used to aide in the diagnosis of invasive aspergillosis allowing for earlier recognition of disease compared to conventional methods. Since its implementation in the clinic as a diagnostic tool, GM has been used in experimental models to measure therapeutic response. Several clinical studies describe the prognostic value of GM. Herein, we review the evidence supporting the utilization of GM antigen as a biomarker to measure response to systemic antifungal therapy.

Isavuconazole versus voriconazole for primary treatment of invasive mould disease caused by Aspergillus and other filamentous fungi (SECURE): a phase 3, randomised-controlled, non-inferiority trial

BACKGROUND

Isavuconazole is a novel triazole with broad-spectrum antifungal activity. The SECURE trial assessed efficacy and safety of isavuconazole versus voriconazole in patients with invasive mould disease.

METHODS

This was a phase 3, double-blind, global multicentre, comparative-group study. Patients with suspected invasive mould disease were randomised in a 1:1 ratio using an interactive voice-web response system, stratified by geographical region, allogeneic haemopoietic stem cell transplantation, and active malignant disease at baseline, to receive isavuconazonium sulfate 372 mg (prodrug; equivalent to 200 mg isavuconazole; intravenously three times a day on days 1 and 2, then either intravenously or orally once daily) or voriconazole (6 mg/kg intravenously twice daily on day 1, 4 mg/kg intravenously twice daily on day 2, then intravenously 4 mg/kg twice daily or orally 200 mg twice daily from day 3 onwards). We tested non-inferiority of the primary efficacy endpoint of all-cause mortality from first dose of study drug to day 42 in patients who received at least one dose of the study drug (intention-to-treat [ITT] population) using a 10% non-inferiority margin. Safety was assessed in patients who received the first dose of study drug. This study is registered with ClinicalTrials.gov, number NCT00412893.

FINDINGS

527 adult patients were randomly assigned (258 received study medication per group) between March 7, 2007, and March 28, 2013. All-cause mortality from first dose of study drug to day 42 for the ITT population was 19% with isavuconazole (48 patients) and 20% with voriconazole (52 patients), with an adjusted treatment difference of -1·0% (95% CI -7·8 to 5·7). Because the upper bound of the 95% CI (5·7%) did not exceed 10%, non-inferiority was shown. Most patients (247 [96%] receiving isavuconazole and 255 [98%] receiving voriconazole) had treatment-emergent adverse events (p=0·122); the most common were gastrointestinal disorders (174 [68%] vs 180 [69%]) and infections and infestations (152 [59%] vs 158 [61%]). Proportions of patients with treatment-emergent adverse events by system organ class were similar overall. However, isavuconazole-treated patients had a lower frequency of hepatobiliary disorders (23 [9%] vs 42 [16%]; p=0·016), eye disorders (39 [15%] vs 69 [27%]; p=0·002), and skin or subcutaneous tissue disorders (86 [33%] vs 110 [42%]; p=0·037). Drug-related adverse events were reported in 109 (42%) patients receiving isavuconazole and 155 (60%) receiving voriconazole (p<0·001).

INTERPRETATION

Isavuconazole was non-inferior to voriconazole for the primary treatment of suspected invasive mould disease. Isavuconazole was well tolerated compared with voriconazole, with fewer study-drug-related adverse events. Our results support the use of isavuconazole for the primary treatment of patients with invasive mould disease.

FUNDING

Astellas Pharma Global Development, Basilea Pharmaceutica International.

Therapeutic and immunomodulatory activities of short-course treatment of murine visceral leishmaniasis with KALSOME™10, a new liposomal amphotericin B

BACKGROUND

Visceral leishmaniasis (VL), a potentially fatal disease, is most prevalent in the Indian subcontinent, East Africa and South America. Since the conventional antileishmanial drugs have many limitations we evaluated a new ergosterol rich liposomal amphotericin B formulation, KALSOME™10 for its leishmanicidal efficacy, tolerability and immunomodulatory activity.

METHODS

Normal healthy mice were treated with 3.5 mg/kg single and 7.5 mg/kg single and double doses of KALSOME™10. Liver and kidney function tests were performed fourteen days after treatment. Next, normal mice were infected with Leishmania donovani amastigotes. Two months post infection they were treated with the above mentioned doses of KALSOME™10 and sacrificed one month after treatment for estimation of parasite burden in the liver and spleen by Limiting Dilution Assay. Leishmanial antigen stimulated splenocyte culture supernatants were collected for cytokine detection through ELISA. Flow cytometric studies were performed on normal animals treated with KALSOME™10, Amphotericin B (AmB) and AmBiosome to compare their immunomodulatory activities.

RESULTS

The drug was found to induce no hepato- or nephrotoxicities at the studied doses. Moreover, at all doses, it led to significant reduction in parasite burden in two month infected BALB/c mice, with 7.5 mg/kg double dose resulting in almost complete clearance of parasites from both liver and spleen. Interestingly, the drug at 7.5 mg/kg double dose could almost completely inhibit the secretion of disease promoting cytokines, IL-10 and TGFβ, and significantly elevate the levels of IFNγ and IL-12, cytokines required for control of the disease. Mice treated with KALSOME™10 showed elevated levels of IFNγ and suppressed IL-10 secretion from both CD4(+) and CD8(+) subsets of T cells, as well as from culture supernatants of splenocytes, compared to that of normal, AmB and AmBisome treated animals.

CONCLUSIONS

Treatment of infected mice with 7.5 mg/kg double dose of KALSOME™10 was safe and effective in clearing the parasites from the sites of infection. The drug maintains the inherent immunomodulatory activities of AmB by effectively suppressing disease promoting cytokines IL-10 and TGFβ, thereby boosting IL-12 and IFNγ levels. This emphasizes KALSOME™10 as a promising drug alternative for lifelong protection from VL.

Anti-Candida activity of 1-18 fragment of the frog skin peptide esculentin-1b: in vitro and in vivo studies in a Caenorhabditis elegans infection model

Candida albicans represents one of the most prevalent species causing life-threatening fungal infections. Current treatments to defeat Candida albicans have become quite difficult, due to their toxic side effects and the emergence of resistant strains. Antimicrobial peptides (AMPs) are fascinating molecules with a potential role as novel anti-infective agents. However, only a few studies have been performed on their efficacy towards the most virulent hyphal phenotype of this pathogen. The purpose of this work is to evaluate the anti-Candida activity of the N-terminal 1-18 fragment of the frog skin AMP esculentin-1b, Esc(1-18), under both in vitro and in vivo conditions using Caenorhabditis elegans as a simple host model for microbial infections. Our results demonstrate that Esc(1-18) caused a rapid reduction in the number of viable yeast cells and killing of the hyphal population. Esc(1-18) revealed a membrane perturbing effect which is likely the basis of its mode of action. To the best of our knowledge, this is the first report showing the ability of a frog skin AMP-derived peptide (1) to kill both growing stages of Candida; (2) to promote survival of Candida-infected living organisms and (3) to inhibit transition of these fungal cells from the roundish yeast shape to the more dangerous hyphal form at sub-inhibitory concentrations.

Current status of antifungal resistance and its impact on clinical practice

Mortality linked to invasive fungal diseases remains very high despite the availability of novel antifungals and new therapeutic strategies. Candida albicans and Aspergillus fumigatus account for most invasive mycosis produced by yeast or moulds, respectively. Other Candida non-albicans are increasingly being reported and newly emerging, as well as cryptic, filamentous fungi often cause disseminated infections in immunocompromised hosts. Management of invasive fungal infections is becoming a challenge as emerging fungal pathogens generally show poor response to many antifungals. The ability of reference antifungal susceptibility testing methods to detect emerging resistance patterns, together with the molecular characterization of antifungal resistance mechanisms, are providing useful information to optimize the effectiveness of antifungal therapy. The current status of antifungal resistance epidemiology with special emphasis on the molecular resistant mechanisms that have been described in the main pathogenic fungal species are reviewed.

Disseminated infection due to Saksenaea vasiformis secondary to cutaneous mucormycosis

Mucormycosis is an uncommon opportunistic fungal infection caused by Zygomycetes. It usually affects immunocompromised, diabetic and trauma patients with infected wounds. We report a case of disseminated infection secondary to facial cutaneous mucormycosis caused by Saksenaea vasiformis in a diabetic patient who had a farming accident causing him severe head injury. The patient was treated with a combination of surgical debridement and antifungal therapy with liposomal amphotericin B, but he had a slow and fatal outcome. In cases of tissue necrosis following trauma involving wound contact with soil (i.e., potential fungal contamination), testing for the presence of Zygomycetes fungi such as S. vasiformis in both immunocompetent and immunocompromised patients is crucial. The reason is that this infection usually has a rapid progression and may be fatal if appropriate treatment is not administered.

Diagnosis and treatment of invasive fungal infections focus on liposomal amphotericin B

Invasive fungal infections (IFIs) are responsible for significant morbidity and mortality, especially in immunocompromised patients and in those requiring admission to an intensive care unit. The epidemiology of IFI is changing, and an increment in non-Aspergillus filamentous fungi and non-Candida albicans species has been observed. The present paper reviews the epidemiology and diagnosis of IFIs. Regarding the treatment of IFIs, it focuses primarily on the role of liposomal amphotericin B in this setting. The main recommendations put forth by expert societies and groups are discussed.

Healthcare-associated mucormycosis

Mucormycosis is a severe emerging invasive fungal infection that occurs as a consequence of environmental exposure. We exhaustively reviewed all the cases of mucormycosis (European Organisation for Research and Treatment of Cancer/Mycoses Study Group 2008 criteria) attributed to healthcare procedures that occurred between 1970 and 2008. A total of 169 cases were studied (29% children, 61% male). Major underlying diseases were solid organ transplantation (24%), diabetes mellitus (22%), and severe prematurity (21%). Skin was the most common localization (57%), followed by gastrointestinal tract (15%). Culture results were available in 75% (92% positive), and results of histological examination were positive in 95%. Rhizopus was the most frequent genus (43%). Infection portal of entry included surgery and presence of medical devices such as catheters or adhesive tape. Outbreaks and clusters were related to adhesive bandages (19 cases), wooden tongue depressors (n = 5), ostomy bags (n = 2), water circuitry damage (n = 2), and adjacent building construction (n = 5). Thorough investigations are mandatory to identify healthcare-associated mucormycosis, notably in neonatology, hematological, and transplantation units.

Antimicrobial decapeptide KSL-W attenuates Candida albicans virulence by modulating its effects on Toll-like receptor, human β-defensin, and cytokine expression by engineered human oral mucosa

We investigated the toxicity of synthetic antimicrobial decapeptide KSL-W on normal human gingival epithelial cell cultures, its effect on Candida albicans adhesion and growth, and the activation of epithelial cell innate immunity. Our results indicate that KSL-W had no toxic effect on cell adhesion or growth, suggesting its safe use with human cells. Pre-treating C. albicans with KSL-W attenuated the yeast's virulence as demonstrated by its reduced adhesion and growth on engineered human oral mucosa epithelium and the subsequent decreased expression of some innate defense molecules by targeted epithelial cells. Indeed, the expression of Toll-like receptors and human β-defensins was reduced in tissues infected with KSL-W-treated Candida. Proinflammatory cytokine secretion (IL-1β and IL-6) by the epithelial cells was also regulated by KSL-W in a manner similar to that of antifungal molecule amphotericin B. These findings therefore show that KSL-W is safe for use with human cells and is able to attenuate Candida virulence by modulating its effects on host innate immunity. This study proposes the potential application of KSL-W peptide as an alternative antifungal agent.

Tinea incognito Caused by Microsporum gypseum in a Patient with Advanced HIV Infection: A Case Report

The prevalence and the clinical relevance of dermatophytoses in HIV-infected patients are poorly documented, particularly for those caused by tinea incognito. Here, we report a case of widespread facial tinea incognito occurring in an Italian patient with advanced HIV infection, showing both skin and brain lesions. Second-line treatment with liposomal amphotericin B and cotrimoxazole, administered after a microbiological characterization of the skin scrapings, led to complete clearance of all lesions.

Breakthrough Hormographiella aspergillata infections arising in neutropenic patients treated empirically with caspofungin

Hormographiella aspergillata, a filamentous basidiomycete, has rarely been involved in human infections. We describe 2 febrile neutropenic patients who developed a severe pulmonary infection due to H. aspergillata while receiving empirical caspofungin therapy for presumed fungal pneumonia. After introduction of liposomal amphotericin B, one patient, who had neutrophil recovery, presented a favorable outcome, while the other, who remained neutropenic throughout the course of infection, died. Resistant fungi, including basidiomycetes, may emerge during empirical treatment with caspofungin in febrile neutropenic patients. A rapid switch to any other potent antifungal should be rapidly considered in case of failure of caspofungin in this setting.

[Management of candidemia and invasive candidiasis]

Candida species is the fourth most common cause of bloodstream infection and is the leading cause of invasive fungal infection among hospitalized patients. Acute disseminated candidiasis remains a life-threatening disease that now occurs mainly in intensive care units hospitalized patients. Delay in treatment of Candida bloodstream infections could be minimized by the development of more rapid and sensitive diagnostic techniques for the identification of Candida bloodstream infections. Current guidelines for the management of invasive candidiasis recommend fluconazole or an echinocandin as the primary therapeutic option. The optimal choice of the antifungal agent should depend on local epidemiology, prior antifungal therapy and patient's characteristics.

Differences in tissue drug concentrations following intravenous versus intraperitoneal treatment with amphotericin B deoxycholate or liposomal amphotericin B

Amphotericin B formulations were compared in preclinical models by using intraperitoneal (ip) and intravenous (iv) delivery of amphotericin B deoxycholate (DAMB) or liposomal amphotericin B. We examined the effects on drug tissue penetration and retention resulting from different routes of drug administration. Mice were treated with equivalent total doses of AmBisome (AmBi) or DAMB (i.e.,15 mg/kg) given ip (3 mg/kg/day for 5 days) or iv (3 mg/kg/day AmBi for 5 days or 1 mg/kg/day DAMB for 15 days), with tissues collected 24 h post-treatment. For drug retention studies, mice were given iv or ip total doses of 30 mg/kg AmBi (10 mg/kg/day 3 x /week) or 60 mg/kg AmBi (20 mg/kg/day 3 x /week) with tissue collection 24 h or 7 days post-treatment. Blood samples were collected at 0.5 h, 2 h, 8 h, 12 h and 24 h after ip or iv drug dosing. A Paecilomyces variottii bioassay was used to determine drug concentrations. AmBi and DAMB were detected in the kidneys following iv, but not ip dosing. Significantly more DAMB than AmBi was detected in the lungs with ip dosing (P = 0.008), and more AmBi than DAMB (P = 0.056) was present with iv dosing. Unlike the lungs, the spleen and liver retained the AmBi for up to one week post-treatment regardless of the route of drug administration. Thus, there are significant differences in AmBi and DAMB tissue distribution depending upon the drug route and these differences could effect how the drugs perform in fungal infection models.

Liposomal amphotericin B and echinocandins as monotherapy or sequential or concomitant therapy in murine disseminated and pulmonary Aspergillus fumigatus infections

Monotherapy and combination therapy were compared using optimal doses of liposomal amphotericin B, micafungin, or caspofungin in Aspergillus fumigatus pulmonary and disseminated infections. Mice were challenged intravenously (2.8 x 10(4) to 5.7 x 10(4) conidia) or intranasally (5.8 x 10(7) conidia) with A. fumigatus. Drugs (5, 10, or 15 mg/kg of body weight) were given for 3 or 6 days as single, concomitant, or sequential therapy (i.e., days 1 to 3 and then days 4 to 6). Mice were monitored for survival, and tissues were assayed for fungal burden and drug concentrations. Treatments starting 24 h postchallenge significantly prolonged survival in disseminated aspergillosis (P < 0.002), but only liposomal amphotericin B treatments or treatments beginning with liposomal amphotericin B increased survival to 100% in the pulmonary aspergillosis model. Fungi in kidneys and spleens (disseminated) and lungs (pulmonary) were significantly decreased (P < or = 0.04) by liposomal amphotericin B, liposomal amphotericin B plus echinocandin, or liposomal amphotericin B prior to echinocandin. In the disseminated infection, liposomal amphotericin B and micafungin (10 or 15 mg/kg) had similar kidney drug levels, while in the spleen, 5 and 15 mg/kg liposomal amphotericin B gave higher drug levels than micafungin (P < 0.02). In the pulmonary infection, drug levels in lungs and spleen with 5-mg/kg dosing were significantly higher with liposomal amphotericin B than with caspofungin (P < or = 0.002). In summary, treatment of A. fumigatus infections with liposomal amphotericin B plus echinocandin or liposomal amphotericin B prior to echinocandin was as effective as liposomal amphotericin B alone, and a greater decrease in the fungal burden with liposomal amphotericin B supports using liposomal amphotericin B prior to echinocandin.

[Invasive pulmonary aspergillosis in a hematooncological patient in the intensive care units. A review of the literature]

Invasive aspergillosis is a common condition in patients with hematologic malignancies. Symptoms are extremely non-specific, and therefore it is necessary to be familiar with the diagnostic tests for early diagnosis. This review has attempted to clarify the current evidence regarding the following areas: clinical presentation, methods of study and treatment of this condition in hemato-oncological critical patients.

Comparison between concentrations of amphotericin B in infected lung lesion and in uninfected lung tissue in a patient treated with liposomal amphotericin B (AmBisome)

Generally, the primary lesion of a mold infection is in the airway, an extravascular site. Therefore, the antifungal drug concentration at the actual tissue lesion of a mold infection is as important as in the blood compartment. Although our antifungal armamentarium has expanded recently, polyenes are still often needed in clinical practice because of their potent fungicidal activity and the rarity of resistance. Nevertheless, the distribution of amphotericin B (AmB) in infected lung tissue has not yet been evaluated. Using high-performance liquid chromatography analysis, we determined the concentrations of AmB in plasma and infected and uninfected tissues of resected lung simultaneously, in a patient with pulmonary aspergillosis treated with liposomal amphotericin B (L-AmB). The AmB concentration in the infected lesion of the lung was approximately 5.2 times higher than that in plasma and 3.7 times higher than in uninfected lung tissue. L-AmB accumulated in the infected lesion of the lung at a higher concentration. Although our data are from only one patient, they may be useful in helping to develop better strategies for the use of L-AmB against pulmonary fungal infections.

The current role of amphotericin B lipid complex in managing systemic fungal infections

BACKGROUND

An increase in the number of immunocompromised patients has led to a rising burden of systemic fungal infections. Historically, conventional amphotericin B has been used to treat these infections due to its broad spectrum of activity. The development of lipid-based amphotericin B agents, such as Abelcet * (ABLC), has allowed clinicians to take advantage of the broad spectrum of activity of amphotericin B while reducing adverse events. As well as this, a number of new antifungal agents have been developed in recent years which have significantly added to the treating physician's antifungal armamentarium. * Abelcet is a registered trade name of Cephalon Ltd, Herts, UK.

OBJECTIVES

Review the clinical data that support the use of ABLC and discuss the evidence for its continuing role in the treatment of invasive fungal infections in light of the introduction of newer antifungal agents.

METHODS

Published studies were identified by searching the MEDLINE database and the Cochrane Centre for Reviews up to August 2009. The search was conducted using the following key words: Amphotericin, Lipid, Abelcet, AmBisome, Efficacy, Nephrotoxicity, Renal, Toxicity.

FINDINGS

ABLC is effective and well-tolerated in the treatment of systemic fungal infections and remains a valuable therapeutic option in a variety of immunocompromised patients due to its broad antifungal spectrum and rarity of resistance.

LIMITATIONS

Data from randomised controlled trials of lipid-based amphotericin B formulations, as well as head-to-head comparison studies between ABLC and other antifungal agents are limited. In addition, the review uses a narrative approach and relies to a great extent on the authors' personal views and experiences.

A safety and feasibility study comparing an intermittent high dose with a daily standard dose of liposomal amphotericin B for persistent neutropenic fever

A high intermittent dose regimen (group A: 10 mg kg(-1) on day 1, 5 mg kg(-1) on days 3 and 6) was compared with standard dosing (group B: 3 mg kg(-1) per day for 14 days) of liposomal amphotericin B (LAB) for empirical treatment of persistent febrile neutropenia. A total cumulative dose of 1275 mg (group A) and 2800 mg (group B) was administered. Infusion-related adverse drug events, mainly rigors/chills, occurred more frequently with group A (11/45, 24 % infusions) than with group B (12/201, 6 % infusions) (P=0.002), which extended the mean infusion time by 20 min (P=0.001). Creatinine levels were similar in the two regimens: the A : B ratio of the area under the curve for creatinine (AUC(CREATININE)) for days 2-7 was 1.09 (P=0.27) and for days 2-14 was 1.05 (P=0.51). Rises in creatinine were mild (clinical toxicity criteria 1) in all patients with elevations. Hypokalaemia tended to be less severe in group A with a lower proportion of hypokalaemic days [57/143 (39 %) vs 80/137 (58 %), P=0.21], a higher AUC(POTASSIUM) (A : B ratio of 1.06, P=0.12), a lower proportion of patients with hypokalaemia at the end of study (10 vs 61 %, P=0.01) and fewer potassium-supplemented days [12/210 (6 %) vs 41/210 (19.5 %), P<0.1]. There were mildly elevated median levels of serum bilirubin, alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase, which were similar for the two regimens and were usually associated with other co-existing co-morbid conditions. The AUC for these enzymes was also similar in the two groups. No patient had discontinuation of the study drug due to toxicity. Composite success was identical for each regimen (11/15 patients, 73 %). Three of the fifteen patients in group B and none in group A developed invasive fungal infections (IFIs). Beta-D-Glucan levels were similar in both groups for patients without an IFI [AUC(GLUCAN) of 362 and 683 (P=0.36) for groups A and B, respectively]. The rate of defervescence was similar for each regimen (P=0.75). This feasibility study suggests that a short intermittent high-dose course of 10/5/5 mg LAB kg(-1) on days 1, 3 and 6 may be as safe and effective as a standard 14 day course of 3 mg kg(-1) per day, with drug-acquisition cost savings and reduced drug exposure. A larger study is indicated for confirmation of this.

[Clinical use of micafungin for the treatment of invasive candidiasis in critical ill patients]

BACKGROUND

Over the last 30 years a significant increase of Candida spp. invasive disease has been observed in non-neutropenic critical ill patients. Both fluconazole and amphotericin B have been considered first line treatment for invasive (proven and probable) Candida spp. disease, although the mortality rate is still high.

OBJECTIVES

To review the current data on the use of micafungin for the treatment of Candida invasive disease in critical ill patients.

METHODS

The pharmacologic, mycological and clinical properties of micafungin are reviewed based on current published data. The use and efficacy of micafungin for the treatment of Candida invasive disease in critical ill patients is discussed.

RESULTS AND CONCLUSIONS

To reduce the rate of mortality more effective antifungals and pre-emptive treatment strategies are currently warranted. Candins achieve better results for the treatment of invasive Candida disease in non-neutropenic critical ill patients. Micafungin has a good safety profile (similar to fluconazole). Micafungin is a first line drug for the treatment of invasive Candida disease and may be used as a pre- emptive approach followed by a de-escalating strategy with azoles.

In vitro efficacy of nisin Z against Candida albicans adhesion and transition following contact with normal human gingival cells

AIM

To investigate the nisin Z innocuity using normal human gingival fibroblast and epithelial cell cultures, and its synergistic effect with these gingival cells against Candida albicans adhesion and transition from blastospore to hyphal form.

METHODS AND RESULTS

Cells were cultured to 80% confluence and infected with C. albicans in the absence or presence of various concentrations of nisin Z. Our results indicate that only high concentrations of nisin Z promoted gingival cell detachment and differentiation. Determination of the LD(50) showed that the fibroblasts were able to tolerate up to 80 microg ml(-1) for 24 h, dropping thereafter to 62 mug ml(-1) after 72 h of contact, compared to 160 microg ml(-1) after 24 h, and 80 microg ml(-1) after 72 h recorded by the gingival epithelial cells which displayed a greater resistance to nisin Z. The use of nisin Z even at low concentration (25 microg ml(-1)) at appropriate concentrations with gingival cells significantly reduced C. albicans adhesion to gingival monolayer cultures and inhibited the yeast's transition.

CONCLUSION

These findings show that when used at non-toxic levels for human cells, nisin Z can be effective against C. albicans adhesion and transition and may synergistically interact with gingival cells for an efficient resistance against C. albicans.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests the potential usefulness of nisin Z as an antifungal agent, when used in an appropriate range.

Managing cryptococcosis in the immunocompromised host

PURPOSE OF REVIEW

Expanding access to antiretroviral treatment has dramatically improved the long-term prognosis of patients with HIV-associated cryptococcal disease who survive the acute infection. However, the incidence and acute mortality of HIV-associated cryptococcal meningitis remain high. In this context, this review summarizes urgently needed recent work aimed at improving the acute management of cryptococcal infection in immunocompromised hosts.

RECENT FINDINGS

Studies have started to optimize antifungal regimens and address the complications of raised cerebrospinal fluid pressure and cryptococcal immune reconstitution syndrome. Amphotericin B at 1 mg/kg per day has been shown to be more rapidly fungicidal than the standard dose of 0.7 mg/kg per day, and new data support the importance of combination therapy with flucytosine. Amphotericin B and fluconazole at 800 mg is an alternative combination that appears superior to amphotericin B alone. At a dosage of 400 mg per day, fluconazole alone is much less rapidly fungicidal than amphotericin B and is associated with the development of secondary resistance.

SUMMARY

Recent findings support the use of rapidly fungicidal initial antifungal therapy with amphotericin B-based combination treatment. Where amphotericin B treatment is not yet feasible, studies are needed to optimize oral regimens. Based on accumulating data on rate of clearance of infection, the most promising new regimens in terms of fungicidal activity and safety could be selected for clinical endpoint trials.