Guidelines for Treatment of Candidiasis

Delivery of Antifungal Agents Using Bioactive and Nonbioactive Bone Cements

Background:

Management of fungal osteomyelitis is prolonged and frequently unsuccessful. Antifungal-impregnated cement is sometimes used as adjunctive therapy.

Objective:

To examine the release of antifungals from biodegradable and nonbiodegradable cement carriers.

Methods:

In vitro methods were used to assess antifungal drug release and antifungal activity of impregnated cements commonly used as adjunctive treatment of osteomyelitis. Cements included thermoplastic, nonbioactive polymers (polymethylmethacrylate [PMMA]) or bioactive agents (hydroxyapatite [HAP], β-tricalcium phosphate [β-TCP]) and were formed into spheres (beads).

Results:

Amphotericin B provided consistent supernatant concentrations (release), between 1.75 and 2.0 ug/mL, over 110 days from all bone cements. Flucytosine and fluconazole were observed for 33–42 days before becoming undetectable from a nonbioactive sphere and 18–22 days from a bioactive sphere. Serum concentrations for micafungin, terbinafine, and anidulafungin impregnated into PMMA rapidly became undetectable, regardless of the matrix used. Investigational β-TCP spheres prolonged release for fluconazole and micafungin, but had no effect on amphotericin B. Serum calcium concentrations decreased 60–80% in all HAP-impregnated drug sphere supernatants. Only amphotericin B–impregnated PMMA impacted supernatant calcium, decreasing concentrations by 50–60%. The antifungal-impregnated beads did not appear to be toxic to osteoblasts during 72 hours of exposure in tissue culture medium.

Conclusions:

Elution characteristics of most antifungals from bone cement spheres are probably not optima) for treatment of deep-seated fungal infections if a similar phenomenon of antifungal release manifests in vivo. Ceramic nonabsorbable impregnated devices must be removed after their lifespan expires and may necessitate another surgical procedure that can increase surgical risk and cost. Bioactive osteoconductive materials may provide a surgical alternative to nonabsorbable matrices. However, there have been no controlled trials demonstrating improved therapeutic outcomes with local therapy and assessing whether biodegradable materials act as a new focus for infection.

Candida albicans Cas5, a regulator of cell wall integrity, is required for virulence in murine and toll mutant fly models

Candida albicans is the most common human fungal pathogen, yet the pathogenesis of C. albicans infection remains incompletely understood. We hypothesized that C. albicans has developed evolutionarily conserved mechanisms to invade disparate hosts and tested whether Toll mutant flies could serve as a model host for high-throughput screening of C. albicans virulence genes. We screened 34 C. albicans mutants defective in putative transcription factor genes (see http://www.tigr.org/tigr-scripts/e2k1/qzhao/page.cgi?num=1 ) by means of a previously established model of invasive candidiasis in Toll mutant flies. C. albicans mutants that displayed attenuated virulence in flies were subsequently tested for virulence in a mouse model of hematogenous candidiasis. Of the 34 C. albicans mutants tested, only the prototrophic cas5Delta/Delta mutant (strain VIC1186) exhibited attenuated virulence in Toll mutant flies that was restored in the complemented strain (VIC1190). Similarly, BALB/c mice infected intravenously with the cas5Delta/Delta mutant had significantly better survival and a lower fungal burden in kidneys and spleen than did those infected with the isogenic wild-type strain DAY185. CAS5 encodes a key transcriptional regulator of genes involved in cell wall integrity and lacks an orthologue in Saccharomyces cerevisiae. Our findings support the notion that Drosophila melanogaster is a promising model for large-scale studies of genes involved in the pathogenesis of C. albicans infection in mammals.

Use of liposomal amphotericin B in critically ill patients: a retrospective, multicenter, clinical study

The clinical use of liposomal amphotericin B in 179 patients admitted to 30 medical-surgical intensive Care Units (ICUs) treated with this agent in 2006 was analyzed. Invasive fungal infections were proven, probable and possible in 44%, 16%, and 25% of cases, respectively. Fungi isolated were Candida albicans (38%), non-albicans Candida spp. (15%) and Aspergillus spp. (7%). The mean duration of treatment was 15 days (mean dose 3.7 mg/kg/day). The drug was used as rescue treatment after fluconazole or caspofungin in 47% of patients and as first line in 52% with a satisfactory clinical response in 54% of cases (72.6% with proven infection). Microbiological eradication was achieved in 68% of cases. Adverse events occurred in 51 patients but were severe in only 4. The use of liposomal amphotericin B both as first line and rescue treatment and mainly for proven invasive fungal infection was associated with a high rate of satisfactory clinical response.

Micafungin: a review of its use in the prophylaxis and treatment of invasive Candida infections in pediatric patients

Intravenous micafungin (Mycamine; Funguard) is an echinocandin indicated in Japan and the EU for the treatment of pediatric patients (including neonates) with invasive candidiasis and as prophylaxis against Candida infection in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). In the EU, micafungin is also indicated in pediatric patients who are expected to have neutropenia for >/=10 days. In Japan, children may also receive micafungin for the treatment of, or as prophylaxis against, invasive Aspergillus infection. Micafungin is not currently approved for use in pediatric patients in the US. Micafungin has very good antifungal activity against a wide range of Candida spp. in vitro. It has a favorable pharmacokinetic profile allowing for once-daily administration, has few drug-drug interactions, and reports of resistance are rare. The results of pediatric substudies indicate that intravenous micafungin is effective in a majority of patients for the treatment of candidemia and other types of invasive candidiasis, and provides effective prophylaxis against invasive fungal infections in pediatric patients undergoing HSCT. The tolerability profile of micafungin in pediatric patients was generally acceptable. In the EU, micafungin is indicated for use when other antifungal medications are not appropriate. Therefore, micafungin provides an alternative to other antifungal agents used in the management of candidemia and invasive candidiasis in pediatric patients, or as prophylaxis against fungal infections in pediatric patients undergoing HSCT.

Recent advances in antifungal prevention and treatment

Invasive fungal infections are important causes of morbidity and mortality in patients with bone marrow failure syndromes and hematological malignancies, or who are undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Current epidemiological trends indicate a shift toward infections by Aspergillus spp., non-albicans Candida spp., and previously uncommon fungal pathogens that have decreased susceptibility to the available antifungal agents. The last two decades have seen substantial improvements in the clinical, laboratory, and radiological diagnosis of these infections and the development of new antifungal compounds. Progress has been made in establishing disease definitions and paradigms for antifungal intervention and in the design and conduct of interventional clinical trials. Collectively, these advances have led to major but ongoing changes in the management of patients at risk of or being affected by invasive fungal infections. This article reviews current approaches to prevention and treatment of opportunistic fungal infections in immunocompromised patients with hematological disorders and discusses novel approaches to antifungal chemotherapy and adjunctive treatments.

[Current treatment of candidemia. Role of anidulafungin]

Despite recent advances in antifungal therapy, the incidence of invasive Candida infections and resulting mortality have remained unchanged in the last few years. In surveillance studies published to date, the estimated incidence of candidemia differs depending on the geographic area and is significantly higher in North America than in Europe. The main predisposing conditions for candidemia are neutropenia, cellular immunity deficit, and alteration of normal microbial flora. Some independent risk factors have been identified, such as previous colonization, antibiotic therapy, central venous catheters, neutropenia, and renal dysfunction. In the last two decades, the proportion of infections due to non-albicans Candida has markedly increased. Although fluconazole use has been considered one of the main causes for the epidemiologic change in invasive candidiasis, especially in the increase of species less sensitive to this agent, this association remains unproven. These recent epidemiological changes are highly important when selecting treatment for candidemia. The echinocandins, which include anidulafungin, represent a step forward in the treatment of these infections. The clinical efficacy, tolerability and safety of anidulafungin have been demonstrated in controlled clinical trials in candidemia and invasive candidiasis. Current recommendations include this antifungal agent in the initial empirical therapy of certain patients, especially in those with a critical clinical situation, previous azole exposure, or the possibility of developing adverse events or drug interactions.

[Role of anidulafungin in critically ill patients]

The most frequent invasive fungal infections in critically ill patients are invasive candidiasis, among which is candidemia. In the last few years, these infections have become more common in intensive care units (ICU), including those produced by species other than Candida albicans. This phenomenon may lead to the development of species resistant to antifungal agents. To start the most appropriate treatment, early diagnosis of the infection is essential, which would reduce empirical antibiotic treatment and increase the proportion of advanced or directed antibiotic therapy. Given the poor reliability of the available diagnostic techniques, new strategies are currently being employed in the ICU, such as the use of scores to evaluate the presence of fungal infections. The therapeutic arsenal against these infections has been increased and the introduction of anidulafungin represents the addition of a highly appropriate drug for the treatment of invasive candidiasis in immunocompetent critically ill patients.

[Current status of invasive fungal infections. New diagnostic techniques and antifungal agents]

In the last few years, major advances in the treatment of transplant recipients, with hemato-oncological diseases or admitted to the intensive care unit, has been accompanied by an increase in classical fungal infections and by the emergence of uncommon fungal infections. Despite the development of new diagnostic techniques such as galactomannan detection and the availability of new antifungal agents, these opportunistic infections continue to pose a diagnostic challenge, prolong length of hospital stay, and increase costs. In addition, mortality from these infections is high. The present chapter provides a brief review of the epidemiology of these infections, diagnostic advances, and the new antifungal agents that have been developed in the last few years.

Prevention and treatment of invasive fungal diseases in neutropenic patients

PURPOSE OF REVIEW

Despite advances in the diagnosis and management, invasive fungal diseases contribute substantially to the morbidity and mortality of patients with prolonged neutropenia.

RECENT FINDINGS

Major advances in the prevention, diagnosis, and treatment of invasive fungal diseases have occurred with the introduction of fungal markers and new antifungal agents over the past decade. The newer broad-spectrum azoles and echinocandins, due to their acceptable safety profiles and efficacy, have emerged as valuable options as antifungal prophylaxis and therapy. Empirical antifungal therapy, a strategy in which persistent neutropenic fever triggers the addition of an antifungal agent, remains a common practice. However, the development of fungal diagnostic markers (e.g. galactomannan and beta-glucan assays) combined with radiologic imaging has given potential to more targeted preemptive antifungal strategies.

SUMMARY

With the validation of preemptive strategies in clinical trials, we will likely have evidence-based targeted use of antifungals. PCR-based techniques are also promising tools for preemptive strategies and are undergoing evaluation. Knowledge of host genetic factors may be important in stratifying the risk for fungal disease during periods of high risk.

Antifungal prophylaxis in liver transplant recipients

Although the overall incidence of fungal infections in liver transplant recipients has declined, these infections still contribute significantly to the morbidity and mortality of patients with risk factors for infection. Although antifungal prophylaxis has been widely studied and practiced, no consensus exists on which patients should receive prophylaxis, with which agent, and for what duration. Numerous studies have attempted to ascertain independent risk factors for invasive fungal infections in liver transplant patients, and these data, in addition to clinical trials, identify several patient groups at exceedingly high risk of fungal infection. These include retransplant patients, patients with renal failure requiring hemodialysis or renal replacement therapy, and those requiring reoperations after transplant. Because the majority of infections occur in the first month after transplantation, prophylaxis should be continued for 4-6 weeks. However, local epidemiology and research should guide decisions regarding choice of agent as well as overall development of interinstitutional guidelines, because the incidence and spectrum of infection may differ dramatically among institutions. Liver Transpl 15:842-858, 2009. (c) 2009 AASLD.

Fluconazole dosing for the prevention or treatment of invasive candidiasis in young infants

BACKGROUND

Young infants are susceptible to developmental factors influencing the pharmacokinetics of drugs. Fluconazole is increasingly used to prevent and treat invasive candidiasis in infants. Dosing guidance remains empiric and variable because limited pharmacokinetic data exist.

METHODS

Our population pharmacokinetic model derived from 357 fluconazole plasma concentrations from 55 infants (23-40 week gestation) illustrates expected changes in fluconazole clearance based upon gestational age, postnatal age, weight, and creatinine. We used a Monte Carlo simulation approach based on parametric description of a patient population's pharmacokinetic response to fluconazole to predict fluconazole exposure (median: 10th and 90th percentile population variability range) after 3, 6, and 12 mg/kg dosing.

RESULTS

For the treatment of invasive candidiasis, a dose of at least 12 mg/kg/d in the first 90 days after birth is needed to achieve an area under the concentration curve (AUC) of >400 mg*h/L and an AUC/minimum inhibitory concentration (MIC) >50 for Candida species with MIC <8 microg/mL in > or =90% of <30 week gestation infants and 80% of 30 to 40 week gestation infants. The more preterm infants achieve a higher median AUC (682 mg*hr/L) compared with more mature infants (520 mg*hr/L). For early prevention of candidiasis in 23 to 29 week infants, a dose of 3 or 6 mg/kg twice weekly during the first 42 days of life is equivalent to an AUC of 50 and 100 mg*hr/L, respectively, and maintains fluconazole concentrations > or =2 or 4 microg/mL, respectively, for half of the dosing interval. For late prevention, the 6 mg/kg dose every 72 hours provides similar exposure to 3 mg/kg daily dose. Infants with serum creatinine > or =1.3 mg/dL have delayed drug clearance and dose adjustment is indicated if creatinine does not improve within 96 hours.

CONCLUSIONS

A therapeutic concentration of fluconazole in premature infants with invasive candidiasis requires dosing substantially greater than commonly recommended in most reference texts. To prevent invasive candidiasis, twice weekly prophylaxis regimens can provide adequate exposure when unit specific MICs are taken into account.

Candida in the ICU

Invasive Candida infections are becoming increasingly recognized in critically ill patients. These infections result in serious morbidity, can be life threatening, and are expensive to manage. Early suspicion of Candida infection and the use of timely and proper antifungal treatment can improve outcome. Although treatment of documented, deep-seated Candida infections in nonneutropenic patients has been studied extensively, guidelines for the management of suspected but undocumented cases of invasive Candida infections in critically ill patients have not been clearly established. Future work should focus on better delineation of the sector of critically ill patients who have suspected invasive Candida infection and who could benefit from the use of empiric antifungal therapy, and on the investigation of novel approaches for the potential salvage of devices infected with Candida species.

Antifungal drug discovery through the study of invertebrate model hosts

There is an urgent need for new antifungal agents that are both effective and non-toxic in the therapy of systemic mycoses. The model nematode Caenorhabditis elegans has been used both to elucidate evolutionarily conserved components of host-pathogen interactions and to screen large chemical libraries for novel antimicrobial compounds. Here we review the use of C. elegans models in drug discovery and discuss caffeic acid phenethyl ester, a novel antifungal agent identified using an in vivo screening system. C. elegans bioassays allow high-throughput screens of chemical libraries in vivo. This whole-animal system may enable the identification of compounds that modulate immune responses or affect fungal virulence factors that are only expressed during infection. In addition, compounds can be simultaneously screened for antifungal efficacy and toxicity, which may overcome one of the main obstacles in current antimicrobial discovery. A pilot screen for antifungal compounds using this novel C. elegans system identified 15 compounds that prolonged survival of nematodes infected with the medically important human pathogen Candida albicans. One of these compounds, caffeic acid phenethyl ester (CAPE), was an effective antifungal agent in a murine model of systemic candidiasis and had in vitro activity against several fungal species. Interestingly, CAPE is a potent immunomodulator in mammals with several distinct mechanisms of action. The identification of CAPE in a C. elegans screen supports the hypothesis that this model can identify compounds with both antifungal and host immunomodulatory activity.

Determinants of mortality in non-neutropenic ICU patients with candidaemia

INTRODUCTION

Candidaemia in critically-ill intensive care unit (ICU) patients is associated with high crude mortality. Determinants of mortality--particularly those amenable to potential modification--are incompletely defined.

METHODS

A nationwide prospective clinical and microbiological cohort study of all episodes of ICU-acquired candidaemia occurring in non-neutropenic adults was undertaken in Australian ICUs between 2001 and 2004. Multivariate Cox regression analyses were performed to determine independently significant variables associated with mortality.

RESULTS

183 episodes of ICU-acquired candidaemia occurred in 183 patients during the study period. Of the 179 with microbiological data, Candida albicans accounted for 111 (62%) episodes and Candida glabrata, 32 (18%). Outcome data were available for 173: crude hospital mortality at 30 days was 56%. Host factors (older age, ICU admission diagnosis, mechanical ventilation and ICU admission diagnosis) and failure to receive systemic antifungal therapy were significantly associated with mortality on multivariate analysis. Among the subset who received initial fluconazole therapy (n = 93), the crude mortality was 52%. Host factors (increasing age and haemodialysis receipt), but not organism- (Candida species, fluconazole MIC), pharmacokinetic- (fluconazole dose, time to initiation), or pharmacodynamic-related parameters (fluconazole dose:MIC ratio) were associated with mortality. Process of care measures advocated in recent guidelines were implemented inconsistently: follow-up blood cultures were obtained in 68% of patients, central venous catheters removed within five days in 80% and ophthalmological examination performed in 36%.

CONCLUSIONS

Crude mortality remains high in Australian ICU patients with candidaemia and is overwhelmingly related to host factors but not treatment variables (the time to initiation of antifungals or fluconazole pharmacokinetic and pharmacodynamic factors). The role and timing of early antifungal intervention in critically-ill ICU patients requires further investigation.

Approaches to the Management of Invasive Fungal Infections in Hematologic Malignancy and Hematopoietic Cell Transplantation

Patients with hematologic malignancy and hematopoietic cell transplant (HCT) recipients are at increased risk for invasive fungal infection (IFI) as a result of immunosuppression or organ damage stemming from their underlying disease, its treatment, or both. Such IFIs can cause significant morbidity and mortality, and the diagnosis and treatment of infected patients frequently are clinically challenging. This article discusses the epidemiology and risk factors for IFI in patients with hematologic malignancy and HCT recipients. The pros and cons of available antifungal agents are discussed, and evolving treatment strategies and recent prophylaxis guidelines from various professional organizations are reviewed. Finally, recommendations are offered for antifungal prophylaxis according to risk group.

Candida albicans tricuspid and pulmonic valve endocarditis: Challenge of relapsing risk and role of combined medical treatment and surgery

Candida albicans endocarditis involves infrequently the tricuspid valve and involvement of the pulmonic valve is rare. We report our experience with an immunosuppressed liver-transplanted female who developed both tricuspid and pulmonic valve endocarditis, review the literature and discuss the importance of effective antimycotic therapy combined with surgical replacement of the affected valve.

Central venous catheter-associated fungemia secondary to mucormycosis

Mucormycosis can cause fatal infections in immuno-compromised persons. Rhinocerebral and pulmonary disease predominate. Diagnosis is challenging, dissemination frequent, and mortality high. Positive blood cultures are rare. We report the first case of central venous catheter-associated mucormycosis fungemia (Mucor circinelloides). Early diagnosis and multi-modal therapy led to clinical and microbiological cure.

Successful treatment of Candida parapsilosis (fluconazole-resistant) osteomyelitis with caspofungin in a HIV patient

Treating Candida arthritis is challenging. We report a case of Candida parapsilosis arthritis successfully treated with caspofungin. We illustrate the likelihood of severe infections due fluconazole resistant C. parapsilosis after extensive fluconazole use and discuss the role of newer antifungal agents in the treatment of arthritis due to Candida spp.

Improving survival of patients with candidaemia: Analysis of prognostic factors from a long-term, nationwide study in Iceland

A population-based epidemiological and clinical study of candidaemia in Iceland was conducted during a 20-y period, 1980-1999. As previously reported, the incidence of candidaemia increased 3.5-fold during the study period, without major changes in species distribution or antifungal resistance (Asmundsdottir et al., J Clin Microbiol 2002;40:3489-92). In this study detailed clinical information was collected and registered on all candidaemic patients (n=165, episodes n=172) in Iceland during 1980-1999. Clinical characteristics were compared between adults and children. Univariate and multivariate analyses were used to determine predictors of 30-d mortality. In comparison with adults, young children with candidaemia more often presented with respiratory distress, without fever p<0.001. Adult patients were more likely to have underlying malignancies (p=0.009) and to have undergone surgical operations (p=0.002). During the study a steady decrease in 30-d case fatality ratio was noted, from 58.8% in 1980-1984, to 26.7% in 1995-1999 (p=0.02). At the same time a more aggressive approach to candidaemia management was documented. In multivariate analysis, prompt removal of central venous catheters (odds ratio for death, 0.22, p=0.004), and septic shock (odds ratio for death, 8.01, p=0.001) were the strongest independent predictors of outcome. Our results underline the strong association between prompt removal of vascular catheters and favourable outcome, suggesting that mortality may be reduced by more aggressive management.

Endogenous ocular candidiasis: Changes in epidemiology and factors associated with poor functional outcome

The evolution of the incidence and the epidemiology of ocular candidiasis in our hospital during the past 12 y, as well as the factors associated with poor functional outcome were analysed. A retrospective study of all cases of ocular candidiasis admitted to a university hospital between 1993 and 2004 was performed. Epidemiological, clinical and final outcome data were recorded. 37 episodes of ocular candidiasis in 36 patients were studied. 28 (75%) episodes occurred between 1993 and 1998 (13.09 episodes/100,000 admissions/y), and all of these patients were intravenous drug users. In contrast, only 9 episodes of ocular candidiasis were recorded between 1999 and 2004 (4.42 episodes/100,000 admissions/y; p<.0001) and 3 (33%) patients were not drug users (p<0.01). 19 (57%) cases had final visual acuity <0.1. Treatment with conventional amphotericin B instead of other newer antifungal drugs was associated with poor visual prognosis in the univariate (p = 0.03) and multivariate (p = 0.03) analysis. In conclusion, the incidence of ocular candidiasis has decreased significantly in recent y and the epidemiology has changed. Currently, one-third of patients are immunocompromised non-drug users. Therapy with conventional amphotericin B instead of newer antifungal drugs appears to be associated with a poorer functional outcome.

Candidaemia and risk of intraocular infection: A Danish hospital-based cohort study

Intraocular infection is a feared complication in patients with candidaemia. We therefore assessed the current risk and prognosis in Danish candidaemia patients. Candidaemia patients at a Danish university hospital were identified prospectively during a 10-y period, 1995-2004, and ophthalmologic records were retrieved retrospectively. Among 203 incident cases of candidaemia, 86 (42%) were examined at least once by an ophthalmologist. Nine patients had retinitis and 1 patient had endophthalmitis; eye involvement was bilateral in 8 and monocular in 2 patients. Lesions were generally mild and progression was observed in only 1 patient. Surgical treatment was not indicated and the median duration of systemic antifungal therapy was 19 d. The median survival time was 77 d for candidaemia patients with eye involvement, 480 d in candidaemia patients without such an involvement, and only 9 d in candidaemia patients without an ophthalmologic examination. In conclusion, the cumulative rate of intraocular infection was 11.6%, but we suspect an underestimation due to the circumstances of the eye examinations and the rapid death of many patients. We continue to recommend eye examinations for candidaemia patients, but timing seems not to be critical if overt signs of infection are absent, thereby facilitating the use of improved diagnostic methods.

Overview of the changing epidemiology of candidemia

Candida spp. are currently the fourth most common cause of bloodstream infections in US hospitals, and the third most common cause of bloodstream infections in the intensive care unit. Over the last 2 decades there has been a shift towards a greater involvement of non-Candida albicans spp. as the cause of candidemia. Several of these non-albicans spp. (e.g., C. glabrata and C. krusei ) exhibit resistance to traditional triazole antifungals like fluconazole, and cross-resistance with newer triazoles, focusing attention on the first-line use of antifungals such as the echinocandins, which possess improved activity against fluconazole-resistant strains. Recent treatment guidelines from the Infectious Diseases Society of America (IDSA) recommend an echinocandin as primary therapy for nonneutropenic or neutropenic patients with moderately severe to severe candidiasis and for patients at risk for infection with a triazole-resistant strain. However, further improvement in candidemia-associated mortality will only be attainable with the development and validation of new diagnostic tools that will allow earlier detection, discrimination, and treatment of invasive candidiasis. Clinicians should remain vigilant to wider emergence of Candida spp. with echinocandin resistance.

Antifungal treatment for invasive Candida infections: a mixed treatment comparison meta-analysis

OBJECTIVES

Invasive fungal infections are a major cause of mortality among patients at risk. Treatment guidelines vary on optimal treatment strategies. We aimed to determine the effects of different antifungal therapies on global response rates, mortality and safety.

METHODS

We searched independently and in duplicate 10 electronic databases from inception to May 2009. We selected any randomized trial assessing established antifungal therapies for confirmed cases of invasive candidiasis among predominantly adult populations. We performed a meta-analysis and then conducted a Bayesian mixed treatment comparison to differentiate treatment effectiveness. Sensitivity analyses included dosage forms of amphotericin B and fluconazole compared to other azoles.

RESULTS

Our analysis included 11 studies enrolling a total of 965 patients. For our primary analysis of global response rates, we pooled 7 trials comparing azoles to amphotericin B, Relative Risk [RR] 0.87 (95% Confidence Interval [CI], 0.78-0.96, P = 0.007, I2 = 43%, P = 0.09. We also pooled 2 trials of echinocandins versus amphotericin B and found a pooled RR of 1.10 (95% CI, 0.99-1.23, P = 0.08). One study compared anidulafungin to fluconazole and yielded a RR of 1.26 (95% CI, 1.06-1.51) in favor of anidulafungin. We pooled 7 trials assessing azoles versus amphotericin B for all-cause mortality, resulting in a pooled RR of 0.88 (95% CI, 0.74-1.05, P = 0.17, I2 = 0%, P = 0.96). Echinocandins versus amphotericin B (2 trials) for all-cause mortality resulted in a pooled RR of 1.01 (95% CI, 0.84-1.20, P = 0.93). Anidulafungin versus fluconazole resulted in a RR of 0.73 (95% CI, 0.48-1.10, P = 0.34). Our mixed treatment comparison analysis found similar within-class effects across all interventions. Adverse event profiles differed, with amphotericin B exhibiting larger adverse event effects.

CONCLUSION

Treatment options appear to offer preferential effects on response rates and mortality. When mycologic data are available, therapy should be tailored.

Novel mucoadhesive extended release tablets for treatment of oral candidosis: "in vivo" evaluation of the biopharmaceutical performance

Mucoadhesive tablets containing nystatin (10 mg) were evaluated in vivo. The assays were carried out with 12 healthy volunteers and the concentration of nystatin in saliva was determined at different times. Tablets remained attached to the buccal mucosa during 270 min +/- 30 min. No evidence of ulceration or bleeding was observed. Typical appearance of intact human buccal mucosa was seen before and after contact with the tablet. The tablets were well accepted by the volunteers, although most of the volunteers reported a light bitter taste, probably due to nystatin. Concentration of nystatin in saliva was several times higher than MIC over a period of approximately 4.5 h, which was in agreement with the behavior observed in vitro. These results allow us to infer that the administration of these mucoadhesive tablets could be advantageous compared to conventional formulations and mucoadhesive extended-release tablets might produce better therapeutic performance than conventional formulations in the treatment of oral candidosis.

Cost-effectiveness of micafungin as an alternative to fluconazole empiric treatment of suspected ICU-acquired candidemia among patients with sepsis: a model simulation

INTRODUCTION

Recent epidemiologic literature indicates that candidal species resistant to azoles are becoming more prevalent in the face of increasing incidence of hospitalizations with candidemia. Echinocandins, a new class of antifungal agents, are effective against resistant candidal species. As delaying appropriate antifungal coverage leads to increased mortality, we evaluated the cost-effectiveness of 100 mg daily empiric micafungin (MIC) vs. 400 mg daily fluconazole (FLU) for suspected intensive care unit-acquired candidemia (ICU-AC) among septic patients.

METHODS

We designed a decision model with inputs from the literature in a hypothetical 1000-patient cohort with suspected ICU-AC treated empirically with either MIC or FLU or no treatment accompanied by a watchful waiting strategy. We examined the differences in the number of survivors, acquisition costs of antifungals, and lifetime costs among survivors in the cohort under each scenario, and calculated cost per quality adjusted life year (QALY). We conducted Monte Carlo simulations and sensitivity analyses to determine the stability of our estimates.

RESULTS

In the base case analysis, assuming ICU-AC attributable mortality of 0.40 and a 52% relative risk reduction in mortality with appropriate timely therapy, compared with FLU (total deaths 31), treatment with MIC (total deaths 27) would result in four fewer deaths at an incremental cost/death averted of $61,446. Similarly, in reference case, incremental cost-effectiveness of MIC over FLU was $34,734 (95% confidence interval $26,312 to $49,209) per QALY. The estimates were most sensitive to the QALY adjustment factor and the risk of candidemia among septic patients.

CONCLUSIONS

Given the increasing likelihood of azole resistance among candidal isolates, empiric treatment of ICU-AC with 100 mg daily MIC is a cost-effective alternative to FLU.

Recent experience with fungaemia: change in species distribution and azole resistance

Owing to a rise in frequency and change in pattern of cases with fungaemia at our tertiary care centre, we conducted a prospective study for 4 months to understand the epidemiology and outcome of this infection. Detailed case histories including management protocol and outcomes were noted. Records of 140 cases with fungaemia (27.1% adult and 72.9% paediatric patients) were analysed. Although C. tropicalis was the most common yeast isolated, significantly higher isolation of C. guilliermondii (30.4%) and C. pelliculosa (17.6%) was noted in paediatric patients; and C. albicans (26.3%) and C. glabrata (10.5%) in adult patients. Rare species isolated included C. ustus (0.7%) and Trichosporon asahii (2.1%). Mortality was high (56.9% and 47.4%, respectively), in both groups of patients. Resistance to azoles (fluconazole, itraconazole, voriconazole) emerged in C. albicans (12.5-18.8%) and C. tropicalis (10.2-13.6%). Antifungal susceptibility testing report modified the therapy from fluconazole to amphotericin B in 8 patients; 5 survived. In conclusion, the study highlighted the rise of non-albicans Candida species in our hospital with differential distribution in paediatric and adult wards and emergence of azole resistance.

The resistance to fluconazole in patients with esophageal candidiasis

CONTEXT

Esophageal candidiasis is often observed in patients with risk factors for its development and fluconazole is the therapeutic choice for the treatment of this disease.

OBJECTIVES

To determine its frequency, by performing upper digestive endoscopy; to determine Candida species involved in its pathogenesis and verify their distribution according with the predisposing factors and to determine susceptibility to fluconazole in the samples.

METHODS

From March 2006 to April 2007, all patients submitted to esophagogastroduodenoscopy at the Digestive Endoscopy Unit in the Oswaldo Cruz University Hospital, Recife, PE, Brazil, were eligible for the study. Samples were collected from patients who presented lesions consistent with esophageal candidiasis in order to identify Candida species and verify their susceptibility to fluconazole. The predisposing factors for the occurrence of esophageal candidiasis were described.

RESULTS

Of 2,672 patients referred to upper endoscopy at the Digestive Endoscopy Unit, 40 (1.5%) had endoscopic findings compatible with esophageal candidiasis. The average age was 49.1 years. Twenty one patients (52.5%) were less than 50 years old, of which 82.6% were infected with HIV. Most of them (52.5%) were males and 65.0% were inpatients. Diseases were identified in 90% of the patients and 21 (52.5%) were HIV positive. Concerning endoscopic findings, severe forms of esophagitis were found in 50% of the patients with CD4 count <200. Non-albicans Candida species were isolated in 22.7% of HIV positive and in 45% HIV negative patients. A total of 6 (14.28%) samples were resistant to fluconazole, while 2 (4.76%) samples had dose depending susceptibility to this drug.

CONCLUSIONS

Esophageal candidiasis prevalence was low, although within the results described by other authors. Male and inpatients were the most affected. The species isolated varied according to the characteristics of each group studied. Both, resistance and dose-depending susceptibility to fluconazole were considered high.

[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.

Consensus statement on the management of invasive candidiasis in Intensive Care Units in the Asia-Pacific Region

Invasive candidiasis has emerged as an important nosocomial infection, especially in critically ill patients. The incidence of candidaemia in Intensive Care Units (ICUs) is 5- to 10-fold higher than in the entire hospital and the crude mortality rate of patients with candidaemia is between 35% and 60%. Candida albicans remains the predominant cause of invasive candidiasis in ICUs, followed by Candida tropicalis, Candida glabrata and Candida parapsilosis. Invasive isolates of Candida spp. remain highly susceptible to fluconazole (>90% susceptible), although among Asia-Pacific countries the susceptibility rate of C. glabrata to fluconazole varies widely from 22% to 72%. Early diagnosis and prompt initiation of antifungal therapy are crucial for the effective treatment of invasive candidiasis. However, invasive candidiasis is difficult to diagnose owing to its non-specific clinical features, and delayed therapy is a major contributor to poor outcomes. Combining clinical risk factors with Candida colonisation parameters appears promising for guiding early interventions. Because of considerable regional variability, local epidemiological knowledge is critical in the effective management of invasive candidiasis among ICU patients in Asia-Pacific.

Epidemiology, management, and risk factors for death of invasive Candida infections in critical care: a multicenter, prospective, observational study in France (2005-2006)

OBJECTIVE

To describe the evolving epidemiology, management, and risk factors for death of invasive Candida infections in intensive care units (ICUs).

DESIGN

Prospective, observational, national, multicenter study.

SETTING

One hundred eighty ICUs in France.

PATIENTS

Between October 2005 and May 2006, 300 adult patients with proven invasive Candida infection who received systemic antifungal therapy were included.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

One hundred seven patients (39.5%) with isolated candidemia, 87 (32.1%) with invasive candidiasis without documented candidemia, and 77 (28.4%) with invasive candidiasis and candidemia were eligible. In 37% of the cases, candidemia occurred within the first 5 days after ICU admission. C. albicans accounted for 57.0% of the isolates, followed by C. glabrata (16.7%), C. parapsilosis (7.5%), C. krusei (5.2%), and C. tropicalis (4.9%). In 17.1% of the isolates, the causative Candida was less susceptible or resistant to fluconazole. Fluconazole was the empirical treatment most commonly introduced (65.7%), followed by caspofungin (18.1%), voriconazole (5.5%), and amphotericin B (3.7%). After identification of the causative species and susceptibility testing results, treatment was modified in 86 patients (31.7%). The case fatality ratio in ICU was 45.9% and did not differ significantly according to the type of episode. Multivariate analysis showed that factors independently associated with death in ICU were type 1 diabetes mellitus (odds ratio [OR] 4.51; 95% confidence interval [CI] 1.72-11.79; p = 0.002), immunosuppression (OR 2.63; 95% CI 1.35-5.11; p = 0.0045), mechanical ventilation (OR 2.54; 95% CI 1.33-4.82; p = 0.0045), and body temperature >38.2 degrees C (reference, 36.5-38.2 degrees C; OR 0.36; 95% CI 0.17-0.77; p = 0.008).

CONCLUSIONS

More than two thirds of patients with invasive candidiasis in ICU present with candidemia. Non-albicans Candida species reach almost half of the Candida isolates. Reduced susceptibility to fluconazole is observed in 17.1% of Candida isolates. Mortality of invasive candidiasis in ICU remains high.

Evolving role of early antifungals in the adult intensive care unit

BACKGROUND

Invasive candidiasis (IC) is associated with significant morbidity and mortality in critically ill patients. This, in conjunction with difficulties in diagnosis, underscores the need for novel treatment strategies based on the identification of significant risk factors for IC.

OBJECTIVE

To review the evidence surrounding the use of early antifungals in critically ill adult patients and to present concise and specific recommendations for different early treatment strategies for IC.

DATA SOURCES AND DATA EXTRACTION

Pubmed search from 1966 to July 2008 using the search terms "antifungals, critical care, prophylaxis, preemptive therapy, and empiric therapy." Examined all relevant peer-reviewed original articles, meta-analyses, guidelines, consensus statements, and review articles.

CONCLUSION

The use of early antifungal therapy should be reserved for patients with a high risk (10% to 15%) of developing IC. Despite a large number of articles published on this topic, there is no single predictive rule that can adequately forecast IC in critically ill patients. Until further prospective validation of existing data is completed, clinicians should assess patients on a case-by-case basis and determine the need for early antifungal treatment strategies based on frequent evaluations of risk factors and clinical status.

Candida infective endocarditis: report of 15 cases from a prospective multicenter study

Candida species are an uncommon cause of infective endocarditis (IE). Given the rarity of this infection, the epidemiology, prognosis, and optimal therapy of Candida IE are poorly defined. We conducted a prospective, observational study at 18 medical centers in Italy, including all consecutive patients with a definite diagnosis of IE admitted from January 2004 through December 2007.A Candida species was the causative organism in 8 cases of prosthetic valve endocarditis (PVE), 5 cases of native valve endocarditis (NVE), 1 case of pacemaker endocarditis, and 1 case of left ventricular patch infection. Candida species accounted for 1.8% of total cases, and for 3.4% of PVE cases. Most patients (86.6%) had a health care-associated infection. PVE associated with a health care contact occurred after a median of 225 days from valve implantation. Ten patients (66.6%) were treated with caspofungin alone or in combination with other antifungal drugs. The overall mortality rate was 46.6%. Mortality was higher in patients with PVE (5 of 8 cases, 62.5%) than in patients with NVE (2 of 5 patients, 40%). A better outcome was observed in patients treated with a combined medical and surgical therapy.Candida IE should be classified as an emerging infectious disease, usually involving patients with intravascular prosthetic devices, and associated with substantial related morbidity and mortality. Candida PVE usually is a late-onset disease, which becomes clinically evident even several months after an initial episode of transient candidemia.

Reliability of the Vitek 2 yeast susceptibility test for detection of in vitro resistance to fluconazole and voriconazole in clinical isolates of Candida albicans and Candida glabrata

The Vitek 2 yeast susceptibility test was evaluated by testing 122 Candida isolates against fluconazole and voriconazole. Excellent categorical agreement with the CLSI broth microdilution method was observed (97.5% for both the azoles). Moreover, the Vitek 2 system was able to identify all but 2 of 59 investigated fluconazole-resistant organisms.

Identification of the Candida albicans Cap1p regulon

Cap1p, a transcription factor of the basic region leucine zipper family, regulates the oxidative stress response (OSR) in Candida albicans. Alteration of its C-terminal cysteine-rich domain (CRD) results in Cap1p nuclear retention and transcriptional activation. To better understand the function of Cap1p in C. albicans, we used genome-wide location profiling (chromatin immunoprecipitation-on-chip) to identify its transcriptional targets in vivo. A triple-hemagglutinin (HA(3)) epitope was introduced at the C terminus of wild-type Cap1p (Cap1p-HA(3)) or hyperactive Cap1p with an altered CRD (Cap1p-CSE-HA(3)). Location profiling using whole-genome oligonucleotide tiling microarrays identified 89 targets bound by Cap1p-HA(3) or Cap1p-CSE-HA(3) (the binding ratio was at least twofold; P < or = 0.01). Strikingly, Cap1p binding was detected not only at the promoter region of its target genes but also at their 3' ends and within their open reading frames, suggesting that Cap1p may associate with the transcriptional or chromatin remodeling machinery to exert its activity. Overrepresented functional groups of the Cap1p targets (P < or = 0.02) included 11 genes involved in the OSR (CAP1, GLR1, TRX1, SOD1, CAT1, and others), 13 genes involved in response to drugs (PDR16, MDR1, FLU1, YCF1, FCR1, and others), 4 genes involved in phospholipid transport (PDR16, GIT1, RTA2, and orf19.932), and 3 genes involved in the regulation of nitrogen utilization (GST3, orf19.2693, and orf19.3121), suggesting that Cap1p has other cellular functions in addition to the OSR. Bioinformatic analyses of the bound sequences suggest that Cap1p recognizes the DNA motif 5'-MTKASTMA. Finally, transcriptome analyses showed that increased expression generally accompanies Cap1p binding at its targets, indicating that Cap1p functions as a transcriptional activator.

Use of 65kDa mannoprotein gene primers in PCR methods for the identification of five medically important Candida species

We have developed PCR and Multiplex PCR assays for the detection of medically important Candida spp. using different species and genus-specific PCR primers selected within the MP65 gene, a recently cloned gene encoding a mannoprotein adhesin. The genus-specific PCR primers were able to amplify Candida species DNA (100% positivity) whereas DNA from all other isolates tested, belonging to other fungal genera, was not amplified. The species-specific PCR primers allowed differentiation of each of five Candida species by the amplicon length produced. No amplicons were detected using species- or genus-specific primers in several bacterial or human DNA templates. The methods described in this study are reproducible, simple and specific. The total time required for each PCR method was less than 4 h from the extraction to the visualized amplicons after PCR. In conclusion, we developed PCR methods to differentiate the five most medically important Candida species using primers directed to the MP65 gene.

Growth inhibition and ultrastructural alterations induced by Delta24(25)-sterol methyltransferase inhibitors in Candida spp. isolates, including non-albicans organisms

Background

Although Candida species are commensal microorganisms, they can cause many invasive fungal infections. In addition, antifungal resistance can contribute to failure of treatment.

The purpose of this study was to evaluate the antifungal activity of inhibitors of Δ²⁴⁽²⁵⁾-sterol methyltransferase (24-SMTI), 20-piperidin-2-yl-5α-pregnan-3β-20(R)-diol (AZA), and 24(R,S),25-epiminolanosterol (EIL), against clinical isolates of Candida spp., analysing the ultrastructural changes.

Results

AZA and EIL were found to be potent growth inhibitors of Candida spp. isolates. The median MIC₅₀ was 0.5 μg.ml^-1 for AZA and 2 μg.ml^-1 for EIL, and the MIC₉₀ was 2 μg.ml^-1 for both compounds. All strains used in this study were susceptible to amphotericin B; however, some isolates were fluconazole- and itraconazole-resistant. Most of the azole-resistant isolates were Candida non-albicans (CNA) species, but several of them, such as C. guilliermondii, C. zeylanoides, and C. lipolytica, were susceptible to 24-SMTI, indicating a lack of cross-resistance. Reference strain C. krusei (ATCC 6258, FLC-resistant) was consistently susceptible to AZA, although not to EIL. The fungicidal activity of 24-SMTI was particularly high against CNA isolates. Treatment with sub-inhibitory concentrations of AZA and EIL induced several ultrastructural alterations, including changes in the cell-wall shape and thickness, a pronounced disconnection between the cell wall and cytoplasm with an electron-lucent zone between them, mitochondrial swelling, and the presence of electron-dense vacuoles. Fluorescence microscopy analyses indicated an accumulation of lipid bodies and alterations in the cell cycle of the yeasts. The selectivity of 24-SMTI for fungal cells versus mammalian cells was assessed by the sulforhodamine B viability assay.

Conclusion

Taken together, these results suggest that inhibition of 24-SMT may be a novel approach to control Candida spp. infections, including those caused by azole-resistant strains.

Candida glabrata fungaemia in a tertiary centre in Taiwan: antifungal susceptibility and outcomes

The proportion of non-albicans candidaemia has increased during recent decades, especially Candida glabrata. We evaluated the antifungal susceptibility, clinical features and outcome of C. glabrata fungaemia treated in a tertiary centre in Taiwan. All episodes of C. glabrata fungaemia during 1999-2005 were identified from microbiology laboratory records and all C. glabrata isolates were subjected to antifungal susceptibility testing by the broth microdilution method. A total of 177 episodes of C. glabrata fungaemia were documented, accounting for 30% of the 598 episodes of candidaemia. A dramatic decline of C. glabrata causing candidaemia from 2003 (46.8%) to 2005 (15.8%) was noted, accompanied by decreased fluconazole consumption. The most common underlying diseases in these patients were cancer (49%), diabetes (34%) and renal failure (25%). The most common risk factors were central venous catheter use (88%), antimicrobial treatment (87%) and parenteral nutrition (51%). The 30-day all-cause mortality was 48.6%, but only 31% of patients were eventually discharged from the hospital. There was no significant survival difference between patients with C. glabrata and Candida albicans fungaemia. Rates of antifungal susceptibility were 63% for fluconazole, 93% for voriconazole, 96% for caspofungin, 98% for amphotericin B and 99% for flucytosine. The different levels of susceptibility to fluconazole (susceptible, susceptible-dose dependent and resistant) were not significantly associated with 30-day mortality.