Predictors of outcome in cancer patients with candidemia

Invasive candidiasis

Invasive candidiasis is an important fungal disease caused by Candida albicans and, increasingly, non-albicans Candida pathogens. Invasive Candida infections originate most frequently from endogenous human reservoirs and are triggered by impaired host defences. Signs and symptoms of invasive candidiasis are non-specific; candidaemia is the most diagnosed manifestation, with disseminated candidiasis affecting single or multiple organs. Diagnosis poses many challenges, and conventional culture techniques are frequently supplemented by non-culture-based assays. The attributable mortality from candidaemia and disseminated infections is ~30%. Fluconazole resistance is a concern for Nakaseomyces glabratus, Candida parapsilosis, and Candida auris and less so in Candida tropicalis infection; acquired echinocandin resistance remains uncommon. The epidemiology of invasive candidiasis varies in different geographical areas and within various patient populations. Risk factors include intensive care unit stay, central venous catheter use, broad-spectrum antibiotics use, abdominal surgery and immune suppression. Early antifungal treatment and central venous catheter removal form the cornerstones to decrease mortality. The landscape of novel therapeutics is growing; however, the application of new drugs requires careful selection of eligible patients as the spectrum of activity is limited to a few fungal species. Unanswered questions and knowledge gaps define future research priorities and a personalized approach to diagnosis and treatment of invasive candidiasis is of paramount importance.

Analyzing Adherence to the 2016 Infectious Diseases Society of America Guidelines for Candidemia in Cancer Patients

Background

Candidemia is associated with morbidity and mortality in cancer patients. We analyzed adherence to the 2016 Infectious Diseases Society of America (IDSA) candidiasis guidelines and the reasons for guideline nonadherence. We also investigated whether matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) improved time to effective antifungal therapy compared with historical data (median, 43.2 hours).

Methods

Cancer patients with candidemia between 1/1/17 and 12/31/19 were included. Adherence to 7 individual IDSA guideline components was assessed. Composite IDSA guideline adherence (defined as meeting ≥6 guideline components) was also assessed. Charts were reviewed to examine reasons for noncompliance.

Results

Of 157 patients with candidemia, 150 (95.5%) had infectious disease (ID) consultation. The median total time from blood culture collection to antifungal initiation was 42.1 hours. Excluding 39 patients with short treatment due to death, there was 100% adherence with surveillance blood cultures, followed by antifungal susceptibility testing (117/118, 99.2%), initial appropriate therapy (117/118, 99.2%), antifungal duration (110/118, 93.2%), line removal (82/91, 90.1%), eye exams (93/118, 78.8%), and step-down therapy (69/94, 73.4%). A quarter (30/118) did not meet composite IDSA guideline adherence. Univariate logistic regression suggested a relationship between poor cancer prognosis and incomplete adherence to the 2016 IDSA candidiasis guidelines (odds ratio, 8.6; 95% CI, 1.6-47).

Conclusions

The addition of MALDI-TOF did not shorten time to effective antifungal therapy. Nearly all patients were seen by ID for candidemia. Poor cancer prognosis was a common factor for incomplete composite adherence to the 2016 IDSA candidiasis guidelines.

Candidemia Risk Prediction (CanDETEC) Model for Patients With Malignancy: Model Development and Validation in a Single-Center Retrospective Study

BACKGROUND

Appropriate empirical treatment for candidemia is associated with reduced mortality; however, the timely diagnosis of candidemia in patients with sepsis remains poor.

OBJECTIVE

We aimed to use machine learning algorithms to develop and validate a candidemia prediction model for patients with cancer.

METHODS

We conducted a single-center retrospective study using the cancer registry of a tertiary academic hospital. Adult patients diagnosed with malignancies between January 2010 and December 2018 were included. Our study outcome was the prediction of candidemia events. A stratified undersampling method was used to extract control data for algorithm learning. Multiple models were developed-a combination of 4 variable groups and 5 algorithms (auto-machine learning, deep neural network, gradient boosting, logistic regression, and random forest). The model with the largest area under the receiver operating characteristic curve (AUROC) was selected as the Candida detection (CanDETEC) model after comparing its performance indexes with those of the Candida Score Model.

RESULTS

From a total of 273,380 blood cultures from 186,404 registered patients with cancer, we extracted 501 records of candidemia events and 2000 records as control data. Performance among the different models varied (AUROC 0.771- 0.889), with all models demonstrating superior performance to that of the Candida Score (AUROC 0.677). The random forest model performed the best (AUROC 0.889, 95% CI 0.888-0.889); therefore, it was selected as the CanDETEC model.

CONCLUSIONS

The CanDETEC model predicted candidemia in patients with cancer with high discriminative power. This algorithm could be used for the timely diagnosis and appropriate empirical treatment of candidemia.

Predominance of Candida Glabrata among Non-albicans Candida Species in a 16-Year Study of Candidemia at a Tertiary Care Center in Lebanon

Background: Candidemia is associated with a high mortality rate, and its incidence is increasing worldwide with a rise in non-albicans candidemia (NAC). Epidemiologic data from Arab countries are scarce and there are no data from Lebanon; Methods: This is a single-center retrospective chart review of patients with candidemia in a tertiary care center in Lebanon from 2004 to 2019. We extracted data on patient characteristics, isolated Candida species antifungal susceptibility, management and outcomes; Results: We included 170 cases of candidemia. NAC was more common than albicans candidemia (64.7% vs. 35.3%). C. glabrata was the most common non-albicans species (37 isolates) followed by C. tropicalis (14). Recent use of antifungals was a risk factor for NAC (OR = 2.8, p = 0.01), while the presence of a central venous catheter was protective (OR = 0.41, p = 0.02). Fluconazole resistance was 12.5% in C. albicans and 21.5% in non-albicans spp. Mortality at 30 days was 55.5%, with no difference between NAC and albicans candidemia. It was higher in older and critically ill patients but lower in patients whose central venous catheter was removed after detecting fungemia; Conclusions: Candidemia is associated with high mortality in Lebanon, with a predominance of NAC and high prevalence of C. glabrata.

Chronic disseminated candidiasis manifesting as hepatosplenic abscesses among patients with hematological malignancies

BACKGROUND

The outcomes of deep-seated abscesses attributed to chronic disseminated candidiasis (CDC) in patients with hematological malignancies have rarely been reported in recent years.

METHODS

We retrospectively reviewed and analyzed the data of patients with hematological malignancies who received a diagnosis of CDC at a medical center in Taiwan between 2008 and 2013.

RESULTS

Sixty-one patients (32 men and 29 women) were diagnosed with CDC. The median age was 51 years (range: 18-83). The overall incidence of CDC was 1.53 per 100 patient-years in patients with hematological malignancies between 2008 and 2013. The highest incidence of CDC was 4.3 per 100 patient-years for acute lymphoblastic leukemia, followed by 3.6 for acute myeloid leukemia. We detected 3 (4.9%) proven, 13 (21.3%) probable, and 45 (73.8%) possible cases of CDC. A total of 13 patients had positive blood cultures for Candida species: C. tropicalis (8), C. albicans (2), C. glabrata (2), and C. famata (1). The median duration of antifungal treatment was 96 days (range: 7-796 days). Serial imaging studies revealed that the resolution rate of CDC was 30.0% at 3 months and 54.3% at 6 months. Five patients (8.2%) had residual lesions that persisted beyond one year. A multivariate analysis of the 90-day outcome revealed that shock was the only independent prognostic factor of 90-day survival in patients with CDC.

CONCLUSION

The incidence of CDC did not decrease between 2008 and 2013. Patients with acute leukemia had a higher risk of CDC than those with other hematological malignancies. Imaging studies conducted at 6 months after diagnosis revealed that only half of the patients showed complete resolution. CDC requires prolonged treatment, and serial imaging at 6 months interval is suggested. Shock is the only independent prognostic factor of 90-day survival in patients with CDC.

Efficacy of Caspofungin in Unclassified Invasive Fungal Infection Cases: A Retrospective Analysis of Patients with Hematological Malignancies in China

Background

The management of invasive fungal infection (IFI) is challenging in immunocompromised patients who do not fully satisfy the EORTC/MSG diagnostic criteria of proven or probable IFI. Our study assessed caspofungin efficacy in 582 Chinese patients with hematological malignancies exhibiting unclassified signs or symptoms of IFI.

Material/Methods

This retrospective study included caspofungin treatment outcomes of an unclassified group A (n=401) of patients without microbiological or biomarker results and group B (n=181) patients with positive microbiological or biomarker results. Factors that correlated with clinical outcomes were determined using univariate and multivariate analyses.

Results

Cough (41.8%), expectoration (29.6%), and chest tightness (14.6%) were the most common clinical features, and changes in CT images (88.1%) were more frequently detected than in X-ray images (19.6%) in all patients. Favorable response rates for caspofungin as first-line treatment were 58.2% for group A and 56.3% for group B. Eastern Cooperative Oncology Group (ECOG) score, cardiovascular disease, hemoptysis, and absolute neutrophil count (ANC) <1000/mm³ before antifungal treatment without recovery were associated with unfavorable clinical outcome (P<0.05 for all). Cough and ANC recovery >1000/mm³ were significantly associated with favorable (complete or partial resolution) outcome.

Conclusions

Caspofungin was effective for treating unclassified IFIs of immunocompromised patients. Cardiovascular disease, ECOG score, cough, and/or hemoptysis, as well as ANC count, represent a potential index for estimating response of unclassified IFI patients to caspofungin treatments.

Efficacy of micafungin for the treatment of invasive candidiasis and candidaemia in patients with neutropenia

Neutropenia is linked to the development of invasive candidiasis/candidaemia, for which micafungin has demonstrated efficacy, but evidence in patients with neutropenia is limited. The aim of this study was to evaluate the efficacy of micafungin for the treatment of invasive candidiasis/candidaemia in patients with neutropenia (<500 neutrophils/μL) and without neutropenia. This pooled, post hoc analysis of 2 Phase 3 trials compared micafungin 100 mg/d (adults) and 2 mg/kg/d (paediatrics) with L-AmB 3 mg/kg/d (NCT00106288) and micafungin 100 mg/d and 150 mg/d with caspofungin 70 mg/d followed by 50 mg/d (adults) (NCT00105144); treatment duration 2-4 weeks (≤8 weeks for chronic disseminated candidiasis). Effects of neutropenia duration and Candida spp. on efficacy outcomes (treatment success, clinical and mycological response) were examined. Of 685 patients, 77 had neutropenia. The most common infection in patients with/without neutropenia was due to C. tropicalis (31/77) and C. albicans (295/608) respectively. Overall success was numerically lower in patients with vs without neutropenia (63.6% vs 72.9%). Clinical and mycological response was similar between groups. Neutropenia duration or Candida spp. did not impact micafungin's overall success rate. This analysis supports evidence that micafungin is effective against invasive candidiasis/candidaemia in patients with neutropenia, irrespective of neutropenia duration or Candida spp., although overall success may be lower than in patients without neutropenia.

Invasive fungal infections in acute leukemia

Invasive fungal infection (IFI) is among the leading causes for morbidity, mortality, and economic burden for patients with acute leukemia. In the past few decades, the incidence of IFI has increased dramatically. The certainty of diagnosis of IFI is based on host factors, clinical evidence, and microbiological examination. Advancement in molecular diagnostic modalities (e.g. non-culture-based serum biomarkers such as β-glucan or galactomannan assays) and high-resolution radiological imaging has improved our diagnostic approach. The early use of these diagnostic tests assists in the early initiation of preemptive therapy. Nonetheless, the complexity of IFI in patients with leukemia and the limitations of these diagnostic tools still mandate astute clinical acumen. Its management has been further complicated by the increasing frequency of infection by non-Aspergillus molds (e.g. zygomycosis) and the emergence of drug-resistant fungal pathogens. In addition, even though the antifungal armamentarium has expanded rapidly in the past few decades, the associated mortality remains high. The decision to initiate antifungal treatment and the choice of anti-fungal therapy requires careful consideration of several factors (e.g. risk stratification, local fungal epidemiologic patterns, concomitant comorbidities, drug-drug interactions, prior history of antifungal use, overall cost, and the pharmacologic profile of the antifungal agents). In order to optimize our diagnostic and therapeutic management of IFI in patients with acute leukemia, further basic research and clinical trials are desperately needed.

Serological proteome analysis to identify systemic candidiasis patients in the intensive care unit: Analytical, diagnostic and prognostic validation of anti-Candida enolase antibodies on quantitative clinical platforms

Systemic candidiasis (SC) is associated with high morbidity and mortality, because it generally affects patients with severe underlying diseases and its diagnosis is difficult and often delayed, resulting in delayed therapy. We used serological proteome analysis to screen serum anti-Candida IgG antibody-reactivity profiles in 24 patients under intensive care, 12 of which had confirmed SC (fungal cultures), and in 12 healthy subjects. A total of 15 immunogenic proteins from Candida albicans protoplast lysates were differentially immunorecognized by serum IgG antibodies from SC patients compared to controls. Two-way hierarchical clustering and principal-component analyses of these antibody-reactivity patterns accurately differentiated SC patients from controls. Anti-Eno1p IgG antibodies were found to be present at high abundance in SC patients and be an important molecular fingerprint in serum for SC diagnosis. Differential anti-Eno1p IgG antibody reactivity was further validated by a tag capture ELISA and a Western blot assay in 45 SC patients and 118 non-SC subjects. Both quantitative assays provided comparable analytical, diagnostic and prognostic performances, and verified initial proteomic-profiling results. If confirmed in prospective cohort studies, these anti-Eno1p IgG antibodies might be useful for SC diagnosis. However, these, at least as measured by these clinical platforms, appear to have limited prognostic value in SC patients.

Clinical characteristics of candidaemia in adults with haematological malignancy, and antimicrobial susceptibilities of the isolates at a medical centre in Taiwan, 2001-2010

During the period 2001-2010, a total of 154 episodes of candidaemia were noted in 111 of 2574 patients with haematological malignancies at the National Taiwan University Hospital (Taipei, Taiwan). Patients with acute lymphoblastic leukaemia had a significantly higher rate of candidaemia than patients with other haematological malignancies (odds ratio=2.69; P<0.001). Candida tropicalis was the most common Candida species (n=51; 46%), followed by Candida albicans (n=35; 32%), Candida parapsilosis (n=13; 12%), Candida glabrata (n=8; 7%) and Candida krusei (n=4; 4%). Persistent candidaemia was initially identified in 21 patients (18.9%) and was frequently associated with central venous catheter-related infection (52% vs. 24%; P=0.017). Multivariate analysis revealed that shock (P<0.001), allogeneic transplantation (P=0.033) and elderly age (≥60 years) (P=0.041) were independent prognostic factors of 30-day overall survival in patients with haematological malignancy and candidaemia. Minimum inhibitory concentrations (MICs) of a total of 103 non-duplicate blood isolates of Candida spp., including 82 isolates from 82 patients without persistent candidaemia and 21 isolates causing first episodes among 21 patients with persistent candidaemia, to nine antifungal agents were determined using the broth microdilution method. Among the 103 Candida isolates, 53 (51.5%), 94 (91.3%) and 102 (99.0%) were susceptible to itraconazole, fluconazole and voriconazole, respectively. All Candida isolates were susceptible to caspofungin, and 2 (15%) of the 13 C. parapsilosis isolates were not susceptible to micafungin or anidulafungin. The MIC(90) (MIC for 90% of the organisms) of posaconazole was 0.03 mg/L for C. albicans, 0.5 mg/L for C. tropicalis, 0.12 mg/L for C. parapsilosis and 2 mg/L for C. glabrata.

Invasive Candida infections in patients with haematological malignancies and hematopoietic stem cell transplant recipients: current epidemiology and therapeutic options

In the last decades, the global epidemiological impact of invasive candidiasis (IC) in patients with hematologic malignancies (HM) and in hematopoietic stem cell transplant (HSCT) recipients has decreased and the incidence of invasive aspergillosis exceeded that of Candida infections. The use of prevention strategies, first of all antifungal prophylaxis with triazoles, contributed to the reduction of IC in these populations as demonstrated by several epidemiological studies. However, relatively little is known about the current epidemiological patterns of IC in HM and HSCT populations, because recent epidemiological data almost exclusively derive from retrospective experiences and few prospective data are available. Several prospective, controlled studies in the prophylaxis of invasive fungal diseases have been conducted in both the HM and HSCT setting. On the contrary, most of the prospective controlled trials that demonstrated the efficacy of the antifungal drugs echinocandins and voriconazole in the treatment of candidemia and invasive candidiasis mainly involved patients with underlying conditions other than HM or HSCT. For these reasons, international guidelines provided specific indications for the prophylaxis strategies in HM and HSCT patients, whereas the recommendations on therapy of documented Candida infections are based on the results observed in the general population and should be considered with caution.

Prediction of the clinical outcome in invasive candidiasis patients based on molecular fingerprints of five anti-Candida antibodies in serum

Better prognostic predictors for invasive candidiasis (IC) are needed to tailor and individualize therapeutic decision-making and minimize its high morbidity and mortality. We investigated whether molecular profiling of IgG-antibody response to the whole soluble Candida proteome could reveal a prognostic signature that may serve to devise a clinical-outcome prediction model for IC and contribute to known IC prognostic factors. By serological proteome analysis and data-mining procedures, serum 31-IgG antibody-reactivity patterns were examined in 45 IC patients randomly split into training and test sets. Within the training cohort, unsupervised two-way hierarchical clustering and principal-component analyses segregated IC patients into two antibody-reactivity subgroups with distinct prognoses that were unbiased by traditional IC prognostic factors and other patients-related variables. Supervised discriminant analysis with leave-one-out cross-validation identified a five-IgG antibody-reactivity signature as the most simplified and accurate IC clinical-outcome predictor, from which an IC prognosis score (ICPS) was derived. Its robustness was confirmed in the test set. Multivariate logistic-regression and receiver-operating-characteristic curve analyses demonstrated that the ICPS was able to accurately discriminate IC patients at high risk for death from those at low risk and outperformed conventional IC prognostic factors. Further validation of the five-IgG antibody-reactivity signature on a multiplexed immunoassay supported the serological proteome analysis results. The five IgG antibodies incorporated in the ICPS made biologic sense and were associated either with good-prognosis and protective patterns (those to Met6p, Hsp90p, and Pgk1p, putative Candida virulence factors and antiapoptotic mediators) or with poor-prognosis and risk patterns (those to Ssb1p and Gap1p/Tdh3p, potential Candida proapoptotic mediators). We conclude that the ICPS, with additional refinement in future larger prospective cohorts, could be applicable to reliably predict patient clinical-outcome for individualized therapy of IC. Our data further provide insights into molecular mechanisms that may influence clinical outcome in IC and uncover potential targets for vaccine design and immunotherapy against IC.

High ferritin levels are associated with hepatosplenic candidiasis in hematopoietic stem cell transplant candidates

OBJECTIVES

Invasive fungal infections (IFI) are a significant cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. Hepatosplenic candidiasis (HSC) is defined as a distinct form of invasive candidiasis, with liver, spleen, and kidney involvement, in patients with hematological disorders.

METHODS

The charts of 255 patients (male/female 168/87; median age 35 (range 16-71) years) who were evaluated pre-HSCT at the Gazi University Hospital Stem Cell Transplantation Unit between 2003 and 2008, were retrospectively reviewed.

RESULTS

HSC, which was demonstrated in six (2.3%) patients, was found to be more common in allogeneic HSCT recipients than in autologous HSCT recipients and in patients who had received two or more previous chemotherapy courses than in patients who had received fewer than two (p>0.05). Patients with HSC tended to have a worse performance status than patients without HSC according to the World Health Organization (p=0.001) and Karnofsky scale (p=0.007). Pre-transplantation ferritin (p=0.008) and acute phase reactant levels, including erythrocyte sedimentation rate (p=0.025) and C-reactive protein (p=0.007), were significantly higher in patients with HSC than in patients without HSC.

CONCLUSIONS

This study shows the predictive role of pre-transplantation ferritin levels in selecting a subset of patients at increased risk for HSC. Pre-transplantation risk assessment and targeted strategies might lower the morbidity and mortality of IFI in HSCT recipients.

Candidemia in patients with hematologic malignancies in the era of new antifungal agents (2001-2007): stable incidence but changing epidemiology of a still frequently lethal infection

BACKGROUND

The incidence, epidemiology, Candida species distribution, resistance patterns, and outcome of candidemia in high-risk hematologic malignancy and/or stem cell transplantation patients have not been extensively described since the introduction of new antifungal agents.

METHODS

In this retrospective study, the authors reviewed the medical records and microbiologic data of hematologic malignancy patients with candidemia at The University of Texas M. D. Anderson Cancer Center from March 2001 to February 2007.

RESULTS

The authors analyzed 173 episodes of candidemia (170 patients), 125 (72%) of which were breakthrough cases after prior antifungal agents, mainly fluconazole (28 [22%]), caspofungin (25 [20%]), and voriconazole (18 [14%]). The incidence of candidemia (per 100,000 inpatient days) remained relatively stable, from 13.9 in 2001 to 19.2 in 2006. However, compared with the findings of previous studies at the authors' institution, the frequency of Candida glabrata and C. krusei infection decreased (to 5% and 17%, respectively) and C. parapsilosis (24%) and C. tropicalis (21%) increased. C. parapsilosis fungemia was associated with prior caspofungin use (P<.001). The overall 30-day crude mortality rate was 38%, and the attributable mortality rate was 19%, similar to previous findings at the authors' institution. The Candida species associated with the highest mortality rate was C. glabrata.

CONCLUSIONS

Despite the widespread use of antifungal prophylaxis and the introduction of new antifungal agents, the incidence and associated mortality rates of candidemia remained stable in high-risk hematologic malignancy patients. However, its epidemiological characteristics have shifted, with C. parapsilosis and C. tropicalis becoming more common.

Effect of antifungal therapy timing on mortality in cancer patients with candidemia

Prior studies have shown that delays in treatment are associated with increased mortality in patients with candidemia. The purpose of this study was to measure three separate time periods comprising the diagnosis and treatment of candidemia and to determine which one(s) is associated with hospital mortality. Patients with blood cultures positive for Candida spp. were identified. Subjects were excluded if no antifungal therapy was given or if there was preexisting antifungal therapy. Collected data included the time from blood culture collection to positivity (incubation period), the time from blood culture positivity to provider notification (provider notification period), and the time from provider notification to the first dose of antifungal given (antifungal initiation period). These times were assessed as predictors of inpatient mortality. A repeat analysis was done with adjustments for age, sex, race, underlying cancer, catheter removal, APACHE III score, acute renal failure, neutropenia, and non-Candida albicans species. A total of 106 episodes of candidemia were analyzed. The median incubation time was 32.1 h and was associated with mortality (univariate hazard ratio per hour, 1.025; P = 0.001). The median provider notification and antifungal initiation periods were 0.3 and 7.5 h, respectively, and were not associated with mortality. Adjusted analysis yielded similar results. For cancer patients with candidemia, the incubation period accounts for a significant amount of time, compared with the provider notification and antifungal initiation times, and is associated with in-hospital mortality. Strategies to shorten the incubation time, such as utilizing rapid molecularly based diagnostic methods, may help reduce in-hospital mortality.

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.

Pinpointing prognostic indicators of fungal infections in transplant patients

A number of advances have been made in the prevention and treatment of invasive fungal infections (IFIs) in transplant recipients. However, despite best clinical efforts, patient outcomes are often disappointing. The study of prognostic indicators of IFI for transplant patients may aid in the development of improved prevention measures, or determine more aggressive treatment pathways. Owing to the rarity of IFI, appropriately powered studies are often difficult to achieve; moreover, a lack of standardized outcome definitions make study comparisons difficult. Herein, prognostic indicators for mortality in transplant patients with IFI are reviewed, with a focus on invasive aspergillosis and invasive candidiasis

Reliability of antibodies to Candida methionine synthase for diagnosis, prognosis and risk stratification in systemic candidiasis: A generic strategy for the prototype development phase of proteomic markers

To be able to diagnose systemic candidiasis (SC) and to predict outcomes in SC patients are still challenging tasks for physicians. Previous proteomic studies suggest that anti-Candida methionine synthase (Met6p) IgG antibodies may be a candidate marker for SC. To evaluate their reliability for diagnosis, prognosis and risk stratification in SC, we developed a generic prototype strategy for their measurement in SC. Receiver-operating-characteristic curve analyses revealed a high diagnostic accuracy for this prototype format, which was slightly better to that for the widely used Western blot assays. Multivariate logistic-regression models showed a positive association between serum anti-Met6p IgG antibody levels and SC risk that was independent from established SC risk factors and other baseline variables. After adjusting for and stratifying according to known prognostic factors, a significant trend toward a lower two-month mortality risk with increasing levels was evidenced in SC patients at presentation. We conclude that these antibodies may be useful in discriminating SC from non-SC patients and determining risk stratification in SC. These may also confer protection against SC and be valuable for the design of future immunotherapies. Furthermore, our prototype format has the potential to make impact on other infectious diseases, cancers, allergies or autoimmune disorders.

Nosocomial fungal infections: epidemiology, diagnosis, and treatment

Invasive fungal infections are increasingly common in the nosocomial setting. Furthermore, because risk factors for these infections continue to increase in frequency, it is likely that nosocomial fungal infections will continue to increase in frequency in the coming decades. The predominant nosocomial fungal pathogens include Candida spp., Aspergillus spp., Mucorales, Fusarium spp., and other molds, including Scedosporium spp. These infections are difficult to diagnose and cause high morbidity and mortality despite antifungal therapy. Early initiation of effective antifungal therapy and reversal of underlying host defects remain the cornerstones of treatment for nosocomial fungal infections. In recent years, new antifungal agents have become available, resulting in a change in standard of care for many of these infections. Nevertheless, the mortality of nosocomial fungal infections remains high, and new therapeutic and preventative strategies are needed.

Nonribosomal cyclic peptides: specific markers of fungal infections

Some cyclic peptides and depsipeptides are synthesized in microorganisms by large multienzymes called nonribosomal peptide synthetases. The structures of peptide products originating in this way are complex and diverse and are microorganism-specific. This work proposes the use of fungal cyclic peptides and depsipeptides as extremely specific markers of fungal infections. Since a reliable molecular tool for diagnosing fungal infections at an early stage is still missing, we present mass spectrometry as a new, modern, broadband (with respect to fungal strain) and specific tool for clinical mycologists. More than 40 different fungal species can be rapidly characterized according to specific families of cyclic peptides, and in some cases, a particular fungal strain can be identified on the basis of its cyclopeptide profile. This paper is also aimed at initiating discussion on the biological role of these secondary metabolites, especially of those synthesized by medically important strains. Proven cytotoxic, anti-inflammatory or immunosuppressive activities of some cyclic peptides indicate that these molecules may contribute to the synergistic array of fungal virulence factors and support microbial invasion during fungal infection. In addition to an overview on recent mass spectrometric protocols for cyclic peptide sequencing, the structures of new peptides from Paecilomyces and Pseudallescheria are presented.

Efficacy of caspofungin against invasiveCandida or invasiveAspergillus infections in neutropenic patients

BACKGROUND

Neutropenia is an indicator of poor prognosis in patients with fungal infections. All available clinical trial experience from the caspofungin development program was reviewed to ascertain the efficacy of caspofungin in neutropenic patients with documented invasive aspergillosis (IA) or invasive candidiasis (IC).

METHODS

The review was limited to neutropenic patients with proven IC or proven/probable IA at caspofungin onset. Data were available from four clinical trials. All patients had an absolute neutrophil count < 500/mm(3) at the initiation of caspofungin. In all cases caspofungin was administered as monotherapy at a dose of 50 mg/day, after a 70-mg loading dose. In all patients efficacy was assessed at the completion of caspofungin therapy. Success included complete and partial responses.

RESULTS

Sixty-eight neutropenic patients were identified with documented invasive infection, including 27 with IC and 41 with IA. Most patients had acute or chronic leukemia. A favorable response was noted in 63% (17 of 27 patients) of patients with IC, including a 58% (14 of 24 patients) response as first-line therapy and a 100% (3 of 3 patients) response as salvage therapy. Success in candidemia was 68% (17 of 25 patients). Outcomes across the different Candida species were similar. Favorable responses were noted in 39% (16 of 41 patients) of patients with IA, including a 42% (5 of 12 patients) response as first-line therapy and 38% (11 of 29 patients) response as salvage therapy. Success by site of IA was 40% for pulmonary (12 of 30 patients), 43% for sinus (3 of 7 patients), and 25% for skin/disseminated site (1 of 4 patients).

CONCLUSIONS

A review of the caspofungin database demonstrates that this echinocandin is effective in neutropenic patients with documented cases of IC or IA.

Invasive candidiasis in cancer patients: observations from a randomized clinical trial

BACKGROUND

Invasive candidiasis is a common and serious complication of cancer and its therapy.

METHODS

We retrospectively identified patients with malignancies enrolled in a double-blind randomized trial of caspofungin (50 mg/day after a 70 mg loading dose) vs. conventional amphotericin B (0.6-1.0 mg/kg/day) as treatment of documented invasive candidiasis. A favorable response required complete resolution of signs and symptoms plus eradication of the Candida pathogen(s). The primary efficacy analysis used a modified intention-to-treat (MITT) approach that included all patients with a confirmed diagnosis of invasive candidiasis who received > or =1 dose of study medication.

RESULTS

74/224 (33%) patients in the MITT population had active malignancies. 25/30 (83%) hematological malignancies were acute or chronic leukaemias. 22/44 (50%) solid tumors were related to the gastrointestinal tract. Patients with hematological malignancies tended to be younger (median [range] age: 49 [19-74] vs. 59 [19-81] years) and have higher baseline acute physiology and chronic health evaluation (APACHE) II scores (mean [range]: 17 [0-28] vs. 15 [5-35]) than patients with solid tumors. Neutropenia [< or =500/microl] was present on entry in 23 (77%) patients with hematological malignancies and in one (3%) patient with a solid tumor. Candidemia was demonstrated in 56 (88%) cancer patients. C. albicans was the single most frequent isolate in cancer patients, although the majority of cases were caused by non-albicans species. Cancer patients in the caspofungin arm had more hematological malignancies (55 vs. 29%), higher baseline APACHE II scores (>20 in 36 vs. 15%), more frequent neutropenia (42 vs. 24%), and less C. albicans infections (27 vs. 49%) than the amphotericin B-treated cancer patients. Favorable response rates were 11/18 (61%) and 6/12 (50%) for patients with hematological malignancies treated with caspofungin or amphotericin B, respectively; the corresponding outcomes in patients with solid tumors were 12/15 (80%) and 17/29 (59%) for the 2 treatment arms. 7/14 (50%) caspofungin- and 4/10 (40%) amphotericin B-treated patients who were neutropenic on entry responded favorably. All-cause mortality rates during the study for caspofungin recipients were 11/18 (61%) with hematological malignancies and 6/15 (40%) with solid tumors, and for amphotericin recipients were 4/12 (33%) with hematological malignancies and 6/29 (21%) with solid tumors.

CONCLUSIONS

Underlying cancers, most commonly leukaemias and gastrointestinal tumors, were present in one-third of patients enrolled in this study of invasive candidiasis. Overall, 70% of caspofungin-treated and 56% of amphotericin B-treated cancer patients responded favorably. Response rates were lower for neutropenic leukaemic patients than for non-neutropenic patients with solid tumors in both treatment groups.

Outcome predictors of 84 patients with hematologic malignancies and Fusarium infection

BACKGROUND

Invasive infection by Fusarium sp. is associated with high mortality in patients with hematologic cancer. Yet to the authors' knowledge, little is known regarding predictors of adverse outcome.

METHODS

The authors conducted a retrospective review of the records of patients with hematologic carcinoma and invasive fusariosis who were treated at one institution in the U.S. and at 11 centers in Brazil.

RESULTS

The records of 84 patients were evaluated. Neutropenia was present in 83% and 33 patients had undergone stem cell transplantation. Only 18 patients (21%) were alive 90 days after the diagnosis of fusariosis. Multivariate predictors of poor outcome were persistent neutropenia (hazard ratio [HR] of 5.43; 95% confidence interval [95% CI], 2.64-11.11) and use of corticosteroids (HR of 2.18; 95% CI, 1.98-3.96). The actuarial survival rate of patients without any of these factors was 67% compared with 30% for patients who recovered from neutropenia but were receiving corticosteroids and 4% for patients with persistent neutropenia only. None of the patients with both risk factors survived (P<0.0001).

CONCLUSIONS

Measures to reduce the duration of neutropenia, as well as the judicious use of corticosteroids, may reduce the high mortality rate of fusariosis in patients with hematologic cancer.

Evaluation of the in vitro activity of caspofungin against bloodstream isolates of Candida species from cancer patients: comparison of Etest and NCCLS reference methods

The in vitro activity of caspofungin (CAS) was compared with the activity of fluconazole, itraconazole and amphotericin B against 178 bloodstream Candida spp. from cancer patients. The activities were assessed using the reference NCCLS M-27A microdilution method and the Etest method. With both the NCCLS microdilution reference method and the Etest method, CAS was the most active agent (MIC90s 0.19-0.5 mg/l) against Candida albicans, C. glabrata and C. tropicalis. CAS showed substantial activity against azole-resistant Candida. The percentages of agreement within +/-2 dilutions between the NCCLS reference microdilution method and Etest MICs ranged from 81 to 97%. CAS showed good in vitro activity against invasive azole-susceptible and azole-resistant Candida isolates. The CAS Etest MICs correlated well with the NCCLS reference MICs and may provide more choice for laboratories in assessing the activity of antifungal agents. The clinical correlation of these in vitro observations needs to be established.

Antifungal drug resistance of pathogenic fungi

Pathogenic fungi have many complex mechanisms of resistance to antifungal drugs. Information about the clinical, cellular, and molecular factors contributing to antifungal-drug resistance continues to accumulate. We critically review the diagnosis, epidemiology, and mechanisms of antifungal drug resistance of pathogenic fungi. Better understanding of this resistance should assist in developing better detection strategies for preventing and treating refractory mycoses in the future.

Transcription factors regulating the response to oxidative stress in yeast

A main avenue of defense against fungal infection uses oxidative killing of these and other microorganisms. Consequently, the ability of fungi to withstand an oxidative challenge has important implications for their ultimate pathogenicity in a host organism. Fungi also serve as an excellent model system for handling of reactive oxygen species in eukaryotic cells. For these reasons, a great deal of work has been invested in analyzing pathways involved in and the mechanisms regulating oxidative stress tolerance in fungi. The goal of this review is to discuss the current state of knowledge underlying the ability of fungal cells to mount a response to oxidative stress via activation of transcription factors. Studies in Saccharomyces cerevisiae have identified multiple transcriptional regulatory proteins that mediate tolerance to oxidative stress. Experiments focused on the fission yeast Schizosaccharomyces pombe have led to the discovery of protein kinase cascades highly related to mammalian stress-activated protein kinases. Recent studies on the pathogenic yeast Candida albicans have allowed analysis of the role of a critical oxidant-regulated transcription factor in this important human pathogen. Further understanding of oxidative stress resistance pathways in fungi is an important step toward understanding the molecular pathogenesis of these microorganisms.