Guidelines for Treatment of Candidiasis

A review of Candida species causing blood stream infection

The incidence of candidemia has been on a rise worldwide. The epidemiology of invasive fungal infections in general and of candidemia in particular has changed in the past three decades because of a variety of factors like the AIDS epidemic, increased number of patients receiving immunosuppressive therapy for transplantation and the increasing use of antimicrobials in the hospital setups and even in the community. The important risk factors for candidemia include use of broad-spectrum antimicrobials, cancer chemotherapy, mucosal colonization by Candida species, indwelling vascular catheters like central venous catheters, etc. More than 90% of the invasive infections due to Candida species are attributed to five species-Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis and Candida krusei. However, the list of new species of Candida isolated from clinical specimens continues to grow every year. Early diagnosis and proper treatment is the key for management of candidemia cases.

The impact of systemic fungal infection in patients with perforated oesophagus

INTRODUCTION

Perforated oesophagus is a surgical emergency with significant morbidity and mortality. Systemic fungal infection represents a poor response to the magnitude of the insult, which adds significantly to the risk of morbidity and mortality in these patients. We reviewed our experience with this group of patients over a six-year period in a tertiary referral centre.

METHODS

A retrospective clinical review was conducted of patients who were admitted following a ruptured oesophagus over a period of six years (January 2002 - January 2008).

RESULTS

We had 27 admissions (18 men and 9 women) following an isolated perforated oesophagus to our unit. The median patient age was 65 years (range: 22-87 years). The majority (n=24, 89%) presented with spontaneous perforations (Boerhaave's syndrome) and three (11%) were iatrogenic. Fungal organisms, predominantly Candida albicans, were positively cultured in pleural or blood samples in 16 (59%) of the 27 patients. Fourteen patients grew yeasts within the first seven days while two showed a delayed growth after ten days. Overall mortality was 5 out of 27 patients (19%). There was no mortality among the group that did not grow yeasts in their blood/pleural fluid while mortality was 31% (5/16) in the group with systemic fungal infection (p<0.001). A positive fungal culture was also associated with increase ventilation time, intensive care unit stay and inpatient hospital stay but not an increased rate of complications.

CONCLUSIONS

Systemic fungal infection in patients with a ruptured oesophagus affects a significant proportion of these patients and carries a poor prognosis despite advanced critical care interventions. It may represent a general marker of poor host response to a major insult but can add to mortality and morbidity. It is worth considering adding antifungal therapy empirically at an early stage to antimicrobials in patients with an established diagnosis of a perforated oesophagus.

A sticky situation: untangling the transcriptional network controlling biofilm development in Candida albicans

Candida albicans is a commensal microorganism of the human microbiome; it is also the most prevalent fungal pathogen of humans. Many infections caused by C. albicans are a direct consequence of its proclivity to form biofilms—resilient, surface-associated communities of cells where individual cells acquire specialized properties that are distinct from those observed in suspension cultures. We recently identified the transcriptional network that orchestrates the formation of biofilms in C. albicans. These results set the stage for understanding how biofilms are formed and, once formed, how the specialized properties of biofilms are elaborated. This information will provide new insight for understanding biofilms in more detail and may lead to improvements in preventing and treating biofilm-based infections in the future.

Candida spp. isolated from inpatients, the environment, and health practitioners in the Pediatric Unit at the Universitary Hospital of the Jundiaí Medical College, State of São Paulo, Brazil

INTRODUCTION

This study aimed to isolate and identify Candida spp. from the environment, health practitioners, and patients with the presumptive diagnosis of candidiasis in the Pediatric Unit at the Universitary Hospital of the Jundiaí Medical College, to verify the production of enzymes regarded as virulence factors, and to determine how susceptible the isolated samples from patients with candidiasis are to antifungal agents.

METHODS

Between March and November of 2008 a total of 283 samples were taken randomly from the environment and from the hands of health staff, and samples of all the suspected cases of Candida spp. hospital-acquired infection were collected and selected by the Infection Control Committee. The material was processed and the yeast genus Candida was isolated and identified by physiological, microscopic, and macroscopic attributes.

RESULTS

The incidence of Candida spp. in the environment and employees was 19.2%. The most frequent species were C. parapsilosis and C. tropicalis among the workers, C. guilliermondii and C. tropicalis in the air, C. lusitanae on the contact surfaces, and C. tropicalis and C. guilliermondii in the climate control equipment. The college hospital had 320 admissions, of which 13 (4%) presented Candida spp. infections; three of them died, two being victims of a C. tropicalis infection and the remaining one of C. albicans. All the Candida spp. in the isolates evidenced sensitivity to amphotericin B, nystatin, and fluconazole.

CONCLUSIONS

The increase in the rate of hospital-acquired infections caused by Candida spp. indicates the need to take larger measures regarding recurrent control of the environment.

Common infections in kidney transplant recipients

Infections are a major cause of morbidity and mortality in kidney transplant recipients. To some extent, these may be preventable. Careful pretransplant screening, immunization, and post-transplant prophylactic antimicrobials may all reduce the risk for post-transplant infection. However, because transplant recipients may not manifest typical signs and symptoms of infection, diagnoses may be confounded. Furthermore, treatment regimens may be complicated by drug interactions and the need to maintain immunosuppression to avoid allograft rejection. This article reviews common post-transplant infections, including prophylactic, diagnostic, and treatment strategies, providing guidance regarding care of kidney transplant patients with infection.

Comparison of fluconazole renal penetration levels in healthy and Candida albicans-infected Wistar rats

The aims of this study were to evaluate free levels of fluconazole (FCZ) in the kidneys of healthy and Candida albicans-infected Wistar rats using microdialysis and to establish the relationship between free renal and total plasma levels under both conditions. Microdialysis recovery rates were determined in vitro by dialysis, and retrodialysis recovery rates were determined in vivo by retrodialysis. The recovery rate was around 50%, independent of the method, drug concentration, or condition (in vitro or in vivo) used. FCZ kidney penetration in healthy and infected rats was investigated after the administration of 10 mg/kg of body weight intravenously (i.v.) or 50 mg/kg orally (n = 6/group) and blood and microdialysate sample harvesting at predetermined time points up to 24 and 18 h, respectively. There were no statistical differences between the area under the free concentration-time curve (AUC(0-∞)) values in plasma and in tissue for either healthy or infected groups for the same dose regimen investigated. The antifungal tissue penetrations were similar for both doses and under all conditions investigated (ranging from 0.77 to 0.84). The unbound fraction of FCZ was concentration independent (86.0% ± 2.0%), allowing the prediction of free renal levels using pharmacokinetic parameters obtained from total plasma fitting. The results showed that free renal and free plasma levels are similar in healthy and systemically C. albicans-infected rats. Therefore, free plasma levels are a good surrogate to estimate free FCZ renal concentrations in systemic candidiasis and can be used to optimize dosing regimens for this drug.

A review of Candida prophylaxis in the neonatal intensive care population

OBJECTIVE

To review the efficacy and safety of antifungal prophylaxis in the neonatal intensive care setting.

DATA SOURCES

English-language literature was accessed using MEDLINE (January 1988- December 2010). The following Medical Subject Heading (MeSH) search terms were used: "amphotericin B," "fluconazole," "nystatin," "itraconazole," "caspofungin," "voriconazole," "Candida," "prevention and control," and "critically ill." Literature was further limited to studies focusing on patient birth to 6 months of age. Abstracts and original research articles were included. Preference was given to published controlled trials. Articles providing descriptions of the safety and effectiveness of antifungal prophylaxis in neonatal intensive care patients were also used in this review.

RESULTS

Twenty-two studies have evaluated the impact of antifungal prophylaxis on Candida colonization or invasive infections in the Neonatal Intensive Care Unit (NICU). The two antifungal agents most commonly studied were nystatin and fluconazole. All of the nystatin studies demonstrated that nystatin is effective at reducing fungal colonization and invasive fungal infections. All of the studies designed to evaluate the impact of fluconazole prophylaxis on fungal colonization demonstrated a reduction in the incidence of fungal colonization with fluconazole prophylaxis. A total of 12 of 16 studies that evaluated the impact of fluconazole prophylaxis on the incidence of invasive fungal infections demonstrated a reduction in invasive fungal infections with fluconazole prophylaxis. Two studies found no difference between fluconazole and nystatin when used for prophylaxis.

CONCLUSION

Antifungal prophylaxis appears to be effective in reducing the incidence of Candida colonization and invasive Candida infections in the NICU. Antifungal prophylaxis also appears to be safe in the NICU population. The impact of antifungal prophylaxis on resistance patterns could be significant and needs to be evaluated long term before widespread prophylaxis can be recommended.

Aspergillus osteomyelitis of the proximal humerus: a case report

Aspergillus osteomyelitis is an extremely rare manifestation of invasive aspergillosis. Generally, patients in states of significant immune deficiency are very susceptible to invasive aspergillosis. We report a case of Aspergillus osteomyelitis of the proximal humerus in an immunocompetent patient that required aggressive oral antifungal therapy, surgical debridement, and placement of an antifungal-impregnated cement spacer. Subsequently, her shoulder was reconstructed using a reverse total shoulder prosthesis The clinical course, radiographic findings, histology, and management rationale are presented.

Candida colonization in urine samples of ICU patients: determination of etiology, antifungal susceptibility testing and evaluation of associated risk factors

The presence of Candida in urine presents a therapeutic challenge for the physician as it is often asymptomatic, and management guidelines have not been clearly laid down on this issue. The presence of Candida in urine may represent contamination of clinical sample, actual colonization of the lower urinary tract or may be a true indicator of invasive infection of lower and/or upper urinary tract. In a clinical setting like the ICU, multiple risk factors for Candida colonization may be present in the same patient, thereby increasing the chances of candiduria, manifold. In the present study on 80 patients in ICU, high rate of Candida colonization (57.5%) was found in urine samples of ICU patients with C. tropicalis (57.3%) being the predominant species. We also isolated 8 strains of Trichosporon species, all of these presented as a mixed infection along with Candida species. Among the various risk factors studied, urinary catheterization and previous antibiotic therapy were identified as statistically significant (P value <0.05). The minimum inhibitory concentration of the isolates was determined for amphotericin B, fluconazole and itraconazole by E-test. Most of the isolates were susceptible to amphotericin B. The C. parapsilosis strains did not show any drug resistance; however, resistance to fluconazole was observed 18.6, 27.27, 50 and 25% in C. tropicalis, C. albicans, C. glabrata and Trichosporon species, respectively.

Candida glabrata: Multidrug Resistance and Increased Virulence in a Major Opportunistic Fungal Pathogen

C. glabrata is widely acknowledged to be an important and potentially antifungal resistant cause of hematogenously disseminated candidiasis (HDC). In the United States (US) both the frequency of C. glabrata as a cause of HDC and in vitro resistance to fluconazole has increased steadily since 1992. Although this species is generally considered to be less virulent than C. albicans, recent findings suggest that gain of function (GOF) mutations in the transcriptional regulator CgPdr1p results not only in broad resistance to azole antifungals but also an increase in both fitness and virulence in animal models. Furthermore, case reports and case series suggest the emergence of multidrug resistance (MDR) in this species. Recent data from multicenter surveys conducted in the US have demonstrated the emergence of co-resistance to both azoles and echinocandins in clinical isolates of C. glabrata. These findings are highlighted in an effort to bring attention to this important development.

Neonatal fungal infections: when to treat?

Candida infections are a major cause of morbidity and mortality in neonatal intensive care units. Mortality following Candida bloodstream infections is as high as 40%, and neurodevelopmental impairment is common among survivors. Because invasive fungal infections are common and extremely difficult to diagnose, empirical treatment with antifungal therapy should be considered in high-risk, low-birth-weight infants who fail to quickly respond to empirical antibacterial treatment. Risk factors to consider when deciding to administer empirical antifungal therapy include: prior exposure to third-generation cephalosporins, extreme prematurity, and presence of central venous catheters.

Liposomal amphotericin B does not induce nephrotoxicity or renal function impairment in premature neonates

BACKGROUND

Liposomal amphotericin B (LAMB) is frequently administered in NICU to preterm infants <1500 g at birth (VLBW) for treatment of systemic fungal infections (SFI). Concerns exist on safety and tolerability of such drug in patients who are at risk for renal function impairment due to their prematurity.

AIM

To assess the occurrence of renal function impairment related to LAMB in a 10-year cohort of VLBW neonates treated with this drug.

METHODS

Through database search of clinical charts, all VLBW neonates admitted to a 3(rd) level NICU in the years 1998-2007 and undergoing treatment with LAMB were identified. The occurrence of LAMB-attributable renal toxicity was investigated; infants withdrawn from treatment for development of adverse effects or toxicity were identified.

RESULTS

In the study period, 71 of 792 admitted VLBW neonates (8.9%) underwent antifungal treatment with LAMB administered at the recommended dosages (3-to-5 mg/kg/day). Mean duration of treatment was 14 (±9) days, mean cumulative dose given was 58 (±25) mg/kg per infant. Renal compromise, defined as hypokalaemia, and/or elevated creatinine serum levels, and/or decreased urine output, occurred in 2 of 71 (2.8%) treated patients, by 5 (±3) mean days after treatment initiation. In both patients LAMB was withdrawn; renal function impairment was only mild and transient, and normal renal function was restored at discharge. No other significant adverse effects were recorded in any treated neonate.

CONCLUSIONS

LAMB is generally safe and well tolerated in VLBW neonates. The occurrence of LAMB-related nephrotoxicity appears to be uncommon, mild and transient.

Clinical characteristics and response to prophylactic fluconazole of preterm VLBW neonates with baseline and acquired fungal colonisation in NICU: data from a multicentre RCT

BACKGROUND

Fungal colonisation by Candida spp. affects a high proportion of VLBW neonates in NICU. However, few data are available on the clinical characteristics of colonisation in preterm infants who are colonised at baseline via vertical transmission, compared to preterms who become colonised during their stay in NICU via horizontal transmission.

MATERIAL AND METHODS

We reviewed the database of a multicentre, randomised trial of prophylactic fluconazole in VLBW neonates conducted in 8 Italian NICUs in the years 2004 and 2005 (Manzoni et al., NEJM 2007;356(24):2483-95). Per the protocol, all enrolled infants underwent weekly surveillance cultures from birth till discharge. We investigated the frequency of the two different modalities of Candida colonisation in this population, as well as the clinical and outcome characteristics possibly related to them.

RESULTS

Overall, Candida colonisation affected 54 of 336 infants (16.1%). Baseline (i.e., detected <3(rd) day of life) colonisation affected 16 (4.7%), and acquired 38 (11.4%), of the 54 colonised preterms. Infants with baseline colonisation had significantly higher birth weight (1229 ± 28 g vs. 1047 g ± 29, p = 0.01) and gestational age (30.2 wks ± 2.7 vs. 28.5 wks ± 2.6, p = 0.01), and were significantly more likely to limit progression from colonisation to invasive Candida infection when fluconazole prophylaxis was instituted (21.6% vs. 42.7%, p = 0.009). Isolation of C. parapsilosis was significantly more frequent in infants with acquired colonisation.

CONCLUSIONS

Infants with baseline and acquired colonisation differ for demographics characteristics and for their response to fluconazole prophylaxis. This information may be useful for targeting more accurate management strategies for these two different groups of colonised preterms in NICU.

In vivo inhibitory effect on the biofilm formation of Candida albicans by liverwort derived riccardin D

Riccardin D, a macrocyclic bisbibenzyl isolated from Chinese liverwort Dumortiera hirsute, has been proved to have inhibitory effect on biofilms formation of Candida albicans in in vitro study. Our present study aims to investigate the in vivo effect and mechanisms of riccardin D against C. albicans biofilms when used alone or in combination with clinical using antifungal agent fluconazole. XTT reduction assay revealed riccardin D had both prophylactic and therapeutic effect against C. albicans biofilms formation in a dose-dependent manner when using a central venous catheter related infective animal model. Scanning electron microscope and laser confocal scanning microscope showed that the morphology of biofilms was altered remarkably after riccardin D treatment, especially hypha growth inhibition. To uncover the underlying molecular mechanisms, quantitative real-time RT-PCR was performed to observe the variation of related genes. The downregulation of hypha-specific genes such as ALS1, ALS3, ECE1, EFG1, HWP1 and CDC35 following riccardin D treatment suggested riccardin D inhibited the Ras-cAMP-Efg pathway to retard the hypha formation, then leading to the defect of biofilms maturation. Moreover, riccardin D displayed an increased antifungal activity when administered in combination with fluconazole. Our study provides a potential clinical application to eliminate the biofilms of relevant pathogens.

Maternal sepsis, chorioamnionitis, and congenital Candida kefyr infection in premature twins

This is the first reported case of maternal sepsis and placental transmission of Candida kefyr to premature fraternal twins. The mother consumed organic dairy products regularly throughout her pregnancy and developed sepsis with chorioamnionitis caused by C. kefyr. The twins developed respiratory distress at birth. The placenta, fetal membranes, and umbilical cords showed numerous colonies of yeasts, subsequently identified as C. kefyr. C. kefyr sepsis in preterm neonates should be considered when there is a significant maternal history of organic dairy product consumption during pregnancy.

A randomized, double-blind, prospective study of caspofungin vs. amphotericin B for the treatment of invasive candidiasis in newborn infants

BACKGROUND

Caspofungin is an echinocandin agent with fungicidal activity against Candida species.

OBJECTIVE

To assess the efficacy, safety and tolerability of caspofungin relative to amphotericin B in neonates with invasive candidiasis.

PATIENTS AND METHODS

Thirty-two neonates with invasive candidiasis were randomly assigned to receive either caspofungin (n = 15) or amphotericin B (n = 17). Efficacy was evaluated, with a successful outcome defined as fulfilling all the components of a prespecified five-part composite endpoint. Evaluation of safety was done by monitoring drug-related adverse events.

RESULTS

At the end of intravenous therapy, evaluation showed that caspofungin was superior, with a favorable response in 86.7% of patients as compared with 41.7% of those who received amphotericin B (p = 0.04). There were significantly fewer adverse events in the caspofungin group than in the amphotericin B group.

CONCLUSION

Caspofungin is more effective, safer and alternative to amphotericin B for the treatment of invasive candidiasis in newborn infants.

A recently evolved transcriptional network controls biofilm development in Candida albicans

A biofilm is an organized, resilient group of microbes in which individual cells acquire properties, such as drug resistance, that are distinct from those observed in suspension cultures. Here, we describe and analyze the transcriptional network controlling biofilm formation in the pathogenic yeast Candida albicans, whose biofilms are a major source of medical device-associated infections. We have combined genetic screens, genome-wide approaches, and two in vivo animal models to describe a master circuit controlling biofilm formation, composed of six transcription regulators that form a tightly woven network with ∼1,000 target genes. Evolutionary analysis indicates that the biofilm network has rapidly evolved: genes in the biofilm circuit are significantly weighted toward genes that arose relatively recently with ancient genes being underrepresented. This circuit provides a framework for understanding many aspects of biofilm formation by C. albicans in a mammalian host. It also provides insights into how complex cell behaviors can arise from the evolution of transcription circuits.

Candida tropicalis arthritis of the elbow in a patient with Ewing's sarcoma that successfully responded to itraconazole

Fungal infections are rarely responsible for arthritis. Few cases of fungal arthritis have been reported, even in immunocompromised hosts susceptible to low-virulence organisms. Herein, the authors report the first case of Candida tropicalis arthritis in a child with a solid tumor. A 13-year-old boy with Ewing's sarcoma developed arthritis in his elbow during the neutropenic period after chemotherapy. Despite treatment with broad-spectrum antibiotics, his condition did not improve and serial blood cultures failed to reveal any causative organisms. After surgical drainage, culture of the joint fluid revealed the presence of C. tropicalis. Itraconazole treatment was started and after 3 months of therapy, the patient completely recovered full elbow function.

Cutaneous Manifestations of Infectious Diseases

Skin infections account for a significant portion of ­dermatologic diseases. Infections of the skin and subcutaneous tissues are highly diverse in respect to incidence, ­etiologic organisms, and clinical manifestations. Most cases are potentially treatable, thus, it is vital for the clinician to become familiar with the cutaneous expression of local and systemic processes. This chapter covers the clinical presentation, diagnosis, and treatment of the most common bacterial, viral, and fungal mucocutaneous infections encountered in internal medicine.

Miconazole induces fungistasis and increases killing of Candida albicans subjected to photodynamic therapy

Cutaneous and mucocutaneous Candida infections are considered to be important targets for antimicrobial photodynamic therapy (PDT). Clinical application of antimicrobial PDT will require strategies that enhance microbial killing while minimizing damage to host tissue. Increasing the sensitivity of infectious agents to PDT will help achieve this goal. Our previous studies demonstrated that raising the level of oxidative stress in Candida by interfering with fungal respiration increased the efficiency of PDT. Therefore, we sought to identify compounds in clinical use that would augment the oxidative stress caused by PDT by contributing to reactive oxygen species (ROS) formation themselves. Based on the ability of the antifungal miconazole to induce ROS in Candida, we tested several azole antifungals for their ability to augment PDT in vitro. Although miconazole and ketoconazole both stimulated ROS production in Candida albicans, only miconazole enhanced the killing of C. albicans and induced prolonged fungistasis in organisms that survived PDT using the porphyrin TMP-1363 and the phenothiazine methylene blue as photosensitizers. The data suggest that miconazole could be used to increase the efficacy of PDT against C. albicans, and its mechanism of action is likely to be multifactorial.

Multidisciplinary approach to the treatment of invasive fungal infections in adult patients. Prophylaxis, empirical, preemptive or targeted therapy, which is the best in the different hosts?

The high morbidity, mortality, and health care costs associated with invasive fungal infections, especially in the critical care setting and immunocompromised host, have made it an excellent target for prophylactic, empiric, and preemptive therapy interventions principally based on early identification of risk factors. Early diagnosis and treatment are associated with a better prognosis. In the last years there have been important developments in antifungal pharmacotherapy. An approach to the new diagnosis tools in the clinical mycology laboratory and an analysis of the use new antifungal agents and its application in different clinical situations has been made. Furthermore, an attempt of developing a state of the art in each clinical scenario (critically ill, hematological, and solid organ transplant patients) has been performed, trying to choose the best strategy for each clinical situation (prophylaxis, pre-emptive, empirical, or targeted therapy). The high mortality rates in these settings make mandatory the application of early de-escalation therapy in critically ill patients with fungal infection. In addition, the possibility of antifungal combination therapy might be considered in solid organ transplant and hematological patients.

Osteoarticular infection by Candida albicans in an infant with cystic fibrosis

Invasive candidiasis is rare in children after the neonatal period, but can occur in children with (secondary) immunodeficiency with a damaged gastrointestinal or skin barrier, or when receiving antibiotics. A 10-month-old girl was diagnosed as suffering from cystic fibrosis (CF) when showing failure to thrive, pulmonary symptoms and hypoproteinaemia. At that time, Candida albicans was identified from blood culture and treated intravenously with liposomal amphotericin B for 13 days. Six weeks later, the girl presented with osteoarticular infection of the left knee caused by C. albicans. The infection showed insufficient response to therapy with liposomal amphotericin B, but the patient recovered after therapy with fluconazole and flucytosine. Follow-up over 4 years revealed no sequelae. In conclusion, invasive Candida infections may occur in patients with CF, and preventive measures might be considered in patients at risk. In the case of an invasive infection, prolonged treatment with a combination of antifungal drugs may be required.

Anidulafungin compared with fluconazole for treatment of candidemia and other forms of invasive candidiasis caused by Candida albicans: a multivariate analysis of factors associated with improved outcome

BACKGROUND

Candida albicans is the most common cause of candidemia and other forms of invasive candidiasis. Systemic infections due to C. albicans exhibit good susceptibility to fluconazole and echinocandins. However, the echinocandin anidulafungin was recently demonstrated to be more effective than fluconazole for systemic Candida infections in a randomized, double-blind trial among 245 patients. In that trial, most infections were caused by C. albicans, and all respective isolates were susceptible to randomized study drug. We sought to better understand the factors associated with the enhanced efficacy of anidulafungin and hypothesized that intrinsic properties of the antifungal agents contributed to the treatment differences.

METHODS

Global responses at end of intravenous study treatment in patients with C. albicans infection were compared post-hoc. Multivariate logistic regression analyses were performed to predict response and to adjust for differences in independent baseline characteristics. Analyses focused on time to negative blood cultures, persistent infection at end of intravenous study treatment, and 6-week survival.

RESULTS

In total, 135 patients with C. albicans infections were identified. Among these, baseline APACHE II scores were similar between treatment arms. In these patients, global response was significantly better for anidulafungin than fluconazole (81.1% vs 62.3%; 95% confidence interval [CI] for difference, 3.7-33.9). After adjusting for baseline characteristics, the odds ratio for global response was 2.36 (95% CI, 1.06-5.25). Study treatment and APACHE II score were significant predictors of outcome. The most predictive logistic regression model found that the odds ratio for study treatment was 2.60 (95% CI, 1.14-5.91) in favor of anidulafungin, and the odds ratio for APACHE II score was 0.935 (95% CI, 0.885-0.987), with poorer responses associated with higher baseline APACHE II scores. Anidulafungin was associated with significantly faster clearance of blood cultures (log-rank p < 0.05) and significantly fewer persistent infections (2.7% vs 13.1%; p < 0.05). Survival through 6 weeks did not differ between treatment groups.

CONCLUSIONS

In patients with C. albicans infection, anidulafungin was more effective than fluconazole, with more rapid clearance of positive blood cultures. This suggests that the fungicidal activity of echinocandins may have important clinical implications.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00058682.

Diagnosis of invasive fungal infections in hematology and oncology--guidelines from the Infectious Diseases Working Party in Haematology and Oncology of the German Society for Haematology and Oncology (AGIHO)

Invasive fungal infections (IFIs) are a primary cause of morbidity and mortality in patients with hematological malignancies. Establishing a definite diagnosis of IFI in immunocompromised patients is particularly challenging and time consuming, but delayed initiation of antifungal treatment increases mortality. The limited overall outcome has led to the strategy of initiating either 'empirical' or 'preemptive' antifungal therapy before the final diagnosis. However, diagnostic procedures have been vastly improved in recent years. Particularly noteworthy is the introduction of newer imaging techniques and non-culture methods, including antigen-based assays, metabolite detection and molecular detection of fungal DNA from body fluid samples. Though varying widely in cancer patients, the risk of IFI is highest in those with allogeneic stem cell transplantation and those with acute leukemia. The AGIHO presents recommendations for the diagnosis of IFIs with risk-adapted screening concepts for febrile episodes in patients with haemato-oncological disorders.

Population pharmacokinetics of fluconazole in critically ill patients receiving continuous venovenous hemodiafiltration: using Monte Carlo simulations to predict doses for specified pharmacodynamic targets

Fluconazole is a widely used antifungal agent that is extensively reabsorbed in patients with normal renal function. However, its reabsorption can be compromised in patients with acute kidney injury, thereby leading to altered fluconazole clearance and total systemic exposure. Here, we explore the pharmacokinetics of fluconazole in 10 critically ill anuric patients receiving continuous venovenous hemodiafiltration (CVVHDF). We performed Monte Carlo simulations to optimize dosing to appropriate pharmacodynamic endpoints for this population. Pharmacokinetic profiles of initial and steady-state doses of 200 mg intravenous fluconazole twice daily were obtained from plasma and CVVHDF effluent. Nonlinear mixed-effects modeling (NONMEM) was used for data analysis and to perform Monte Carlo simulations. For each dosing regimen, the free drug area under the concentration-time curve (fAUC)/MIC ratio was calculated. The percentage of patients achieving an AUC/MIC ratio greater than 25 was then compared for a range of MIC values. A two-compartment model adequately described the disposition of fluconazole in plasma. The estimate for total fluconazole clearance was 2.67 liters/h and was notably 2.3 times faster than previously reported in healthy volunteers. Of this, fluconazole clearance by the CVVHDF route (CL(CVVHDF)) represented 62% of its total systemic clearance. Furthermore, the predicted efficiency of CL(CVVHDF) decreased to 36.8% when filters were in use >48 h. Monte Carlo simulations demonstrated that a dose of 400 mg twice daily maximizes empirical treatment against fungal organisms with MIC up to 16 mg/liter. This is the first study we are aware of that uses Monte Carlo simulations to inform dosing requirements in patients where tubular reabsorption of fluconazole is probably nonexistent.

Prevalence of antimicrobial resistant pathogens from blood cultures from Canadian hospitals: results of the CANWARD 2007-2009 study

This study assessed the epidemiology and antimicrobial resistance of pathogens associated with bloodstream infections in Canadian hospitals between 2007 and 2009. Tertiary-care medical centers representing 8 of 10 Canadian provinces submitted bloodstream infection pathogens from patients attending hospital clinics, emergency rooms, medical/surgical wards, and intensive care units. Over 8,000 blood culture pathogens were collected. The 10 most common pathogens (representing 80.9% of all isolates) were Escherichia coli (1856 [22.6%]), Staphylococcus aureus (1457 [17.7%] including 1101 methicillin-susceptible Staphylococcus aureus and 356 methicillin-resistant Staphylococcus aureus), coagulase-negative staphylococci (907 [11.0%]), Klebsiella pneumoniae (600 [7.3%]), Streptococcus pneumoniae (470 [5.7%]), Enterococcus faecalis (360 [4.4%]), Pseudomonas aeruginosa (333 [4.0%]), viridans group streptococci (321 [3.9%]), Enterobacter cloacae (193 [2.3%]), and Streptococcus pyogenes (159 [1.9%]). The most active agents against Gram-negative bacilli were carbapenems (e.g., meropenem and ertapenem) and piperacillin-tazobactam, while for Gram-positive cocci, they were vancomycin, linezolid, and daptomycin.

A Critical Appraisal of the Role of the Clinical Microbiology Laboratory in Diagnosis of Invasive Fungal Infections

The incidence of invasive fungal infections (IFIs) continues to rise in industrialized countries, primarily due to both increasingly potent iatrogenic immunosuppression and immunocompromising therapies aimed at treating hematologic malignancies. As this situation continues to evolve, the clinical microbiology laboratory has few new, innovative methodologies to diagnose these serious infections and existing methods lack sensitivity. This represents a difficult clinical situation for health care providers, as they are left to rely on clinical instincts for the management of patients with potential IFIs, as mycology test results are not consistently reliable. The goals of this session of Camp Clin Micro (CCM) were to critically assess currently available methods and practices for diagnosing IFIs, to discuss the potential of current investigational methods, to evaluate the role of antifungal susceptibility testing, and finally to identify action items that can help move the field of diagnostic mycology in a direction that will improve our ability to identify IFIs in a timely manner. This is meant to be not a comprehensive overview of the diagnosis of IFIs but rather a detailed account of the discussion at CCM among clinical microbiologists with experience in diagnostic mycology and knowledge of the literature.

Candidemia in children after complex congenital heart defects surgery treated with caspofungin--our own experience and a review of literature

Background

Invasive fungal infections due to Candida species constitute an increasing clinical problem. There are no guidelines for the management of candidemia in children undergoing surgical procedures for congenital heart defects (CHD). The aim of the study was to draw attention to the problem of candidemia in children who are operated on due to congenital heart defects.

Material/Methods

We retrospectively analyzed medical documentation of 307 children with congenital heart defects treated in 1 clinical centre in Poland, from whom we selected those diagnosed with candidemia during the postoperative period. Next, we analyzed in detail the clinical course of invasive candidiasis in each individual and we performed an analysis of risk factors that lead to candidemia.

Results

In the analyzed period, among 307 children who underwent surgical procedures, we observed 2 cases of candidemia (0.65%) which were effectively cured with caspofungin. No adverse effects were observed after treatment with the drug.

Conclusions

Candidemia in children who undergo surgical treatment of congenital heart defects is an important factor that can influence final clinical results. Caspofungin may be an effective therapeutic option when treating candidemia in children after extensive cardiosurgical procedures.

Oral candidosis--clinical challenges of a biofilm disease

This review summarizes the impact of biofilms in oral candidosis with special emphasis on medically compromised patients. The concept of oral candidosis as a mixed candidal-bacterial biofilm infection has changed our understanding of its epidemiology and diagnosis as well as approach to its treatment. Candida albicans is the most common causative agent of oral candidosis although Candida species other than C. albicans are often seen in medically compromised patients with a history of multiple courses of azole antifungals. Although C. albicans is usually susceptible to all commonly used antifungals when tested in vitro, their biofilm form are highly resistant to most antifungals. Therefore, treatment consists of mechanical destruction of the biofilm in combination with topical drugs. Azole antifungals should be avoided for patients suffering from recurrent oral yeast infections due to a risk of selection and enrichment of resistant strains within the biofilm. Oral candidosis can also be a symptom of an undiagnosed or poorly controlled systemic disease such as HIV infection or diabetes. If the response to appropriate treatment is poor, other causes of oral mucositis should be excluded. Oral candidosis arises from the patient's mixed candidal-bacterial biofilm, i.e., dental plaque, whereby good self-care is important for successful therapy.

[Cost effectiveness of posaconazole versus fluconazole/itraconazole in the prophylactic treatment of invasive fungal infections in Mexico]

Cost effectiveness of posaconazole versus fluconazole/itraconazole therapy in the prophylaxis against invasive fungal Infections among high-risk neutropenic patients in Mexico.

OBJECTIVE

To estimate the cost effectiveness and long-term combined effects of Posaconazole versus fluconazole/itraconazole (standard azole) therapy in the prophylaxis against invasive fungal Infections among high-risk neutropenic patients in Mexico.

METHODS

A previously validated Markov model was used to compare the projected lifetime costs and effects of two theoretical groups of patients, one receiving Posaconazole and the other receiving standard azole. The model estimates total costs, numbers of IFIs, and QALY per patient in each prophylaxis group. To extrapolate trial results to a lifetime horizon, the model was extended with one-month Markov cycles in which mortality risk is specific to the underlying disease. Data on the probabilities of IFI were obtained from Study Protocol PO1899. Drug costs were taken from average wholesale drug reports for 2009. Cost and health effects were discounted at 5% according to the Mexican guideline. The analysis was conducted from the Mexican healthcare perspective using 2008 unit cost prices.

RESULTS

Our model projects an accumulated cost to the Mexican healthcare system per patient receiving the Posaconazol regimen of $US 5,634 compared to $US 7,463 for the standard azole regimen. The accumulated discounted effect is 3.13 LY or 2.25 QALYs per patient receiving Posaconazol, compared to 2.96 LY or 2.13 QALYs per patient receiving standard azole. Posaconazol remained the dominant strategy across each scenario. Probabilistic sensitivity analysis tested numerous assumptions about the model cost and efficacy parameters and found that the results were robust to most changes.

CONCLUSION

Posaconazole provides modest incremental benefits compared with standard azole therapy in the prophylaxis against IFIs among high-risk neutropenic patients. Routine Posaconazole use appears a cost saving when the likelihood of IFIs or the cost of treatment medications is high.