Executive Summary: Clinical Practice Guideline for the Management of Candidiasis: 2016 Update by the Infectious Diseases Society of America

Pharmacodynamic studies of voriconazole: informing the clinical management of invasive fungal infections

INTRODUCTION

Voriconazole is a broad-spectrum antifungal agent commonly used to treat invasive fungal infections (IFI), including aspergillosis, candidiasis, Scedosporium infection, and Fusarium infection. IFI often occur in immunocompromised patients, leading to increased morbidity and mortality.

AREAS COVERED

The objective of this review is to summarize the pharmacodynamic properties of voriconazole and to provide considerations for potential optimal dosing strategies. Studies have demonstrated superior clinical response when an AUC/MIC >25 or Cmin/MIC >1 is attained in adult patients, correlating to a trough concentration range as narrow as 2-4.5 mg/L; however, these targets are poorly established in the pediatric population. Topics in this discussion include voriconazole use in multiple age groups, predisposing patient factors for IFI, and considerations for clinicians managing IFI. Expert commentary: The relationship between voriconazole dosing and exposure is not well defined due to the large inter- and intra-subject variability. Development of comprehensive decision support tools for individualizing dosing, particularly in children who require higher dosing, will help to increase the probability of achieving therapeutic efficacy and decrease sub-therapeutic dosing and adverse events.

Population Pharmacokinetic Model and Pharmacokinetic Target Attainment of Micafungin in Intensive Care Unit Patients

OBJECTIVE

To study the pharmacokinetics of micafungin in intensive care patients and assess pharmacokinetic (PK) target attainment for various dosing strategies.

METHODS

Micafungin PK data from 20 intensive care unit patients were available. A population-PK model was developed. Various dosing regimens were simulated: licensed regimens (I) 100 mg daily; (II) 100 mg daily with 200 mg from day 5; and adapted regimens 200 mg on day 1 followed by (III) 100 mg daily; (IV) 150 mg daily; and (V) 200 mg daily. Target attainment based on a clinical PK target for Candida as well as non-Candida parapsilosis infections was assessed for relevant minimum inhibitory concentrations [MICs] (Clinical and Laboratory Standards Institute). Parameter uncertainty was taken into account in simulations.

RESULTS

A two-compartment model best fitted the data. Clearance was 1.10 (root square error 8%) L/h and V 1 and V 2 were 17.6 (root square error 14%) and 3.63 (root square error 8%) L, respectively. Median area under the concentration-time curve over 24 h (interquartile range) on day 14 for regimens I-V were 91 (67-122), 183 (135-244), 91 (67-122), 137 (101-183) and 183 (135-244) mg h/L, respectively, for a typical patient of 70 kg. For the MIC/area under the concentration-time curve >3000 target (all Candida spp.), PK target attainment was >91% on day 14 (MIC 0.016 mg/L epidemiological cut-off) for all of the dosing regimens but decreased to (I) 44%, (II) 91%, (III) 44%, (IV) 78% and (V) 91% for MIC 0.032 mg/L. For the MIC/area under the concentration-time curve >5000 target (non-C. parapsilosis spp.), PK target attainment varied between 62 and 96% on day 14 for MIC 0.016.

CONCLUSIONS

The licensed micafungin maintenance dose results in adequate exposure based on our simulations with a clinical PK target for Candida infections but only 62% of patients reach the target for non-C. parapsilosis. In the case of pathogens with an attenuated micafungin MIC, patients may benefit from dose escalation to 200 mg daily. This encourages future study.

Candidemia and invasive candidiasis among hospitalized neonates and pediatric patients

OBJECTIVE

To investigate the epidemiology, treatment, length of stay (LOS) and costs for neonatal and pediatric inpatients with invasive candidiasis (IC).

METHODS

The Cerner Health Facts Database was used to assess inpatients (2005-2014) identified by positive blood or cerebrospinal fluid (CSF) Candida cultures. Log-transformed LOS and cost were examined in candidemia-only patients (n = 191) using multivariable linear regression.

RESULTS

A total of 202 patients had a positive culture (blood: n = 192; CSF: n = 10; both: n = 2). The most prevalent species were C. parapsilosis (n = 70, 34.7%), and C. albicans (n = 66, 32.7%). Mean (SD) age was 5 (5.5) years; 30 (14.9%) patients were <4 months. Comorbidities included sepsis (n = 85, 42.1%), coagulation disorders (n = 57, 28.2%), cancer (n = 64, 31.7%), and low birthweight (n = 26, 12.9%). Antifungals (AFs) included azoles (57.4%), polyenes (28.7%), and echinocandins (35.1%); 20.8% of patients received no AF during their encounter. The mean (SD) cost per encounter was $97,392 ($149,253), with a mean (SD) LOS of 45.6 (59.5) days and 9.9% mortality at discharge. Results were similar across Candida species. In regression analysis, intensive care unit (ICU) exposure, central catheter, sepsis, AF >48 hours prior to index culture, and age <4 months were associated with increased LOS; treatment at a non-teaching hospital was associated with reduced LOS (p < .05). AF use >48 hours before index, in-hospital mortality, Midwest region and ventricular shunt were associated with increased cost (p ≤ .05).

CONCLUSIONS

This analysis confirms the association between pediatric candidemia and increased resource utilization and LOS. Given high observed rates of potential under-treatment, an opportunity may exist to improve AF therapy in this population.

Unraveling Drug Penetration of Echinocandin Antifungals at the Site of Infection in an Intra-abdominal Abscess Model

Intra-abdominal candidiasis (IAC) is a prominent invasive fungal infection associated with high mortality. Prompt antifungal therapy and source control are crucial for successful treatment. Echinocandin antifungal drugs are first-line agents; however, their clinical effectiveness is highly variable, with known potential for breakthrough resistance, and little is known about drug exposure at the site of infection. Using matrix-assisted desorption ionization mass spectrometry imaging technology, we investigated the spatial and quantitative distribution in tissue lesions for two echinocandin drugs, micafungin and CD101, in a clinically relevant IAC mouse model. Drug accumulation within lesions was observed with both drugs at their humanized therapeutic doses. CD101, but not micafungin, accumulated in lesions at levels above the mutant prevention concentration of the infecting strain. These findings indicate that current echinocandin drugs are limited by penetration at the site of infection and have implications for clinical outcomes and emergence of resistance in patients with IAC.

Major publications in the critical care pharmacotherapy literature: January-December 2016

PURPOSE

To summarize select critical care pharmacotherapy guidelines and studies published in 2016.

SUMMARY

The Critical Care Pharmacotherapy Literature Update (CCPLU) Group screened 31 journals monthly for relevant pharmacotherapy articles and selected 107 articles for review over the course of 2016. Of those included in the monthly CCPLU, three guidelines and seven primary literature studies are reviewed here. The guideline updates included are as follows: hospital-acquired pneumonia and ventilator-associated pneumonia management, sustained neuromuscular blocking agent use, and reversal of antithrombotics in intracranial hemorrhage (ICH). The primary literature summaries evaluate the following: dexmedetomidine for delirium prevention in post-cardiac surgery, dexmedetomidine for delirium management in mechanically ventilated patients, high-dose epoetin alfa after out-of-hospital cardiac arrest, ideal blood pressure targets in ICH, hydrocortisone in severe sepsis, procalcitonin-guided antibiotic de-escalation, and empiric micafungin therapy.

CONCLUSION

The review provides a synopsis of select pharmacotherapy publications in 2016 applicable to clinical practice.

Multidrug-Resistant Candida: Epidemiology, Molecular Mechanisms, and Treatment

Invasive Candida infections remain an important cause of morbidity and mortality, especially in hospitalized and immunocompromised or critically ill patients. A limited number of antifungal agents from only a few drug classes are available to treat patients with these serious infections. Resistance can be either intrinsic or acquired. Resistance mechanisms are not exchanged between Candida; thus, acquired resistance either emerges in response to an antifungal selection pressure in the individual patient or, more rarely, occur due to horizontal transmission of resistant strains between patients. Although multidrug resistance is uncommon, increasing reports of multidrug resistance to the azoles, echinocandins, and polyenes have occurred in several Candida species, most notably Candida glabrata and more recently Candida auris. Drivers are overall antifungal use, subtherapeutic drug levels at sites of infection/colonization, drug sequestration in the biofilm matrix, and, in the setting of outbreaks, suboptimal infection control. Moreover, recent research suggests that DNA mismatch repair gene mutations may facilitate acquisition of resistance mutations in C. glabrata specifically. Diagnosis of antifungal-resistant Candida infections is critical to the successful management of patients with these infections. Reduction of unnecessary use of antifungals via antifungal stewardship is critical to limit multidrug resistance emergence.

Thinking beyond the Common Candida Species: Need for Species-Level Identification of Candida Due to the Emergence of Multidrug-Resistant Candida auris

Candida species are one of the leading causes of nosocomial infections. Because much of the treatment for Candida infections is empirical, some institutions do not identify Candida to species level. With the worldwide emergence of the multidrug-resistant species Candida auris, identification of Candida to species level has new clinical relevance. Species should be identified for invasive candidiasis isolates, and species-level identification can be considered for selected noninvasive isolates to improve detection of C. auris.

Candidiasis and the impact of flow cytometry on antifungal drug discovery

INTRODUCTION

Invasive candidiasis continues to be associated with significant morbidity and mortality as well as substantial health care costs nationally and globally. One of the contributing factors is the development of resistance to antifungal agents that are already in clinical use. Moreover, there are known treatment limitations with all of the available antifungal agents. Since traditional techniques in novel drug discovery are time consuming, high-throughput screening using flow cytometry presents as a potential tool to identify new antifungal agents that would be useful in the management of these patients. Areas covered: In this review, the authors discuss the use of automated high-throughput screening assays based upon flow cytometry to identify potential antifungals from a library comprised of a large number of bioactive compounds. They also review studies that employed the use of this research methodology that has identified compounds with antifungal activity. Expert opinion: High-throughput screening using flow cytometry has substantially decreased the processing time necessary for screening thousands of compounds, and has helped enhance our understanding of fungal pathogenesis. Indeed, the authors see this technology as a powerful tool to help scientists identify new antifungal agents that can be added to the clinician's arsenal in their fight against invasive candidiasis.

Invasive candidiasis: future directions in non-culture based diagnosis

INTRODUCTION

Delayed initial antifungal therapy is associated with high mortality rates caused by invasive candida infections, since accurate detection of the opportunistic pathogenic yeast and its identification display a diagnostic challenge. diagnosis of candida infections relies on time-consuming methods such as blood cultures, serologic and histopathologic examination. to allow for fast detection and characterization of invasive candidiasis, there is a need to improve diagnostic tools. trends in diagnostics switch to non-culture-based methods, which allow specified diagnosis within significantly shorter periods of time in order to provide early and appropriate antifungal treatment. Areas covered: within this review comprise novel pathogen- and host-related testing methods, e.g. multiplex-PCR analyses, T2 magnetic resonance, fungus-specific DNA microarrays, microRNA characterization or analyses of IL-17 as biomarker for early detection of invasive candidiasis. Expert commentary: Early recognition and diagnosis of fungal infections is a key issue for improved patient management. As shown in this review, a broad range of novel molecular based tests for the detection and identification of Candida species is available. However, several assays are in-house assays and lack standardization, clinical validation as well as data on sensitivity and specificity. This underscores the need for the development of faster and more accurate diagnostic tests.

Consensus Report by the Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplantation Consortium Joint Working Committees on Supportive Care Guidelines for Management of Veno-Occlusive Disease in Children and Adolescents, Part 3: Focus on Cardiorespiratory Dysfunction, Infections, Liver Dysfunction, and Delirium

Some patients with veno-occlusive disease (VOD) have multiorgan dysfunction, and multiple teams are involved in their daily care in the pediatric intensive care unit. Cardiorespiratory dysfunction is critical in these patients, requiring immediate action. The decision of whether to use a noninvasive or an invasive ventilation strategy may be difficult in the setting of mucositis or other comorbidities in patients with VOD. Similarly, monitoring of organ functions may be very challenging in these patients, who may have fulminant hepatic failure with or without hepatic encephalopathy complicated by delirium and/or infections. In this final guideline of our series on supportive care in patients with VOD, we address some of these questions and provide evidence-based recommendations on behalf of the Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplantation Consortium Joint Working Committees.

Recognition and Clinical Presentation of Invasive Fungal Disease in Neonates and Children

Invasive fungal diseases (IFDs) are devastating opportunistic infections that result in significant morbidity and death in a broad range of pediatric patients, particularly those with a compromised immune system. Recognizing them can be difficult, because nonspecific clinical signs and symptoms or isolated fever are frequently the only presenting features. Therefore, a high index of clinical suspicion is necessary in patients at increased risk of IFD, which requires knowledge of the pediatric patient population at risk, additional predisposing factors within this population, and the clinical signs and symptoms of IFD. With this review, we aim to summarize current knowledge regarding the recognition and clinical presentation of IFD in neonates and children.

Significant Publications on Infectious Diseases Pharmacotherapy in 2016

PURPOSE

This is a summary of the most important articles on infectious diseases (ID) pharmacotherapy published in peer-reviewed literature in 2016 as selected by clinical pharmacists with ID expertise.

SUMMARY

The Houston Infectious Diseases Network (HIDN) was asked to identify articles published in peer-reviewed literature in 2016 that were believed to contribute significantly to ID pharmacotherapy, including human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). A list of 46 articles on general ID pharmacotherapy and 8 articles on HIV/AIDS were nominated. Members of the Society of Infectious Diseases Pharmacists (SIDP) were surveyed to select 10 general ID articles believed to have made a significant impact on general ID pharmacotherapy and 1 article most significant to HIV/AIDS pharmacotherapy. Of 445 SIDP members surveyed, 212 (47.6%) and 95 (21.3%) members voted for general ID pharmacotherapy- and HIV/AIDS-related articles, respectively. The 11 highest-ranked papers (10 general ID-related articles and 1 HIV/AIDS-related article) are summarized here.

CONCLUSION

With the large number of ID-related articles published each year, it can be challenging to stay current with the most relevant ID publications. This review of significant publications in 2016 may provide a starting point for that process.

Natural Antimicrobial Peptides as Inspiration for Design of a New Generation Antifungal Compounds

Invasive fungal infections are associated with high mortality rates, despite appropriate antifungal therapy. Limited therapeutic options, resistance development and the high mortality of invasive fungal infections brought about more concern triggering the search for new compounds capable of interfering with fungal viability and virulence. In this context, peptides gained attention as promising candidates for the antimycotics development. Variety of structural and functional characteristics identified for various natural antifungal peptides makes them excellent starting points for design novel drug candidates. Current review provides a brief overview of natural and synthetic antifungal peptides.

Candida Meningitis After Transsphenoidal Surgery: A Single-Institution Case Series and Literature Review

Candida meningitis after neurosurgical procedures is a rare but potentially devastating complication. The presentation of meningitis can be insidious in immunosuppressed patients and thus can be easily overlooked. Cerebrospinal fluid studies often resemble bacterial profiles, and cultures can be falsely negative. Candida albicans is the most common species identified in postsurgical Candida meningitis, and delay in diagnosis and treatment can be devastating. The standard induction therapy for Candida meningitis has been amphotericin B combined with flucytosine. A high index of suspicion is needed in any patient with risk factors such as abdominal surgery, bowel perforation, recent broad spectrum antibiotic therapy, intravenous drug use, extremes of age, indwelling catheters, and immunosuppression such as AIDS, malignancy, antineoplastic therapy, and steroid use. Here, we describe 3 case presentations of patients with giant skull base tumors who developed postsurgical Candida meningitis, each with vastly different clinical courses and outcomes, ranging from benign to catastrophic. We performed a literature review with special focus on common risk factors, Candida species, diagnostic criteria, and treatment.

To which extent can we decrease antibiotic duration in critically ill patients?

INTRODUCTION

Inadequate empirical antibiotic therapy is associated with higher mortality in critically ill patients with severe infections. Nevertheless, prolonged duration of antibiotic treatment is also potentially harmful. Development of new infections with more resistant pathogens is one of the arguments against the administration of prolonged courses of antibiotics. Areas covered: We aim to describe the optimal duration of antimicrobial therapy in the most common infections affecting critically ill patients. A literature search was performed to identify all clinical trials, observational studies, meta-analysis, and reviews about this topic from PubMed. Expert commentary: Diverse observational studies have reported a poor outcome in critically ill patients without a documented infection who receive prolonged antibiotic therapy. We summarize the available information about the optimal duration of antimicrobial therapy in critically ill patients with severe infections including community-acquired pneumonia, intra-abdominal infections, bacteremia, meningitis and urinary-tract infections as well as the clinical consequences of short antimicrobial courses in certain severe infections. The utility of procalcitonin to reduce the duration of antibiotics is also discussed. Finally, we give clear recommendations about the length of treatment for the most common infections in critically ill patients.

Antifungal stewardship considerations for adults and pediatrics

Antifungal stewardship refers to coordinated interventions to monitor and direct the appropriate use of antifungal agents in order to achieve the best clinical outcomes and minimize selective pressure and adverse events. Antifungal utilization has steadily risen over time in concert with the increase in number of immunocompromised adults and children at risk for invasive fungal infections (IFI). Challenges in diagnosing IFI often lead to delays in treatment and poorer outcomes. There are also emerging data linking prior antifungal exposure and suboptimal dosing to the emergence of antifungal resistance, particularly for Candida. Antimicrobial stewardship programs can take a multi-pronged bundle approach to ensure suitable prescribing of antifungals via post-prescription review and feedback and/or prior authorization. Institutional guidelines can also be developed to guide diagnostic testing in at-risk populations; appropriate choice, dose, and duration of antifungal agent; therapeutic drug monitoring; and opportunities for de-escalation and intravenous-to-oral conversion.

Performance of 1,3-β-D-glucan for diagnosing invasive fungal diseases in children

Plasma 1,3-β-D-glucan (BDG) is indicated as a tool for early diagnosis of invasive fungal diseases (IFD). However, data on its diagnostic value are scarce in children. Therefore, definition of BDG test performance in paediatrics is needed. BDG was evaluated in children admitted to "Istituto Giannina Gaslini," Genoa, Italy, who developed clinical conditions at risk for IFD. Results were analysed for sensitivity, specificity, predictive values, likelihood ratios, accuracy, informedness and probability of missing one case by a negative test. A total of 1577 BDG determinations were performed on 255 patients (49% males, median age 5.4 years). Overall 46 IFD were diagnosed, 72% proven/probable. The test performance was evaluated for 80 pg/mL, 120 pg/mL, 200 pg/mL, 350 pg/mL, 400 pg/mL cut offs. Sensitivity was always <0.80 and specificity > 0.90 only for cut offs ≥200 pg/mL. Negative predictive value was ≥0.90 for all the cut offs evaluated, while positive predictive value resulted barely 0.50 (8% IFD prevalence). Accuracy was never >0.90, and informedness was at best 0.50. The risk of missing one IFD by a negative result was < 10%. Analyses in haemato-oncological or newborn patients did not show major differences. Detection of serum BDG does not appear a valuable adjunctive diagnostic tool for IFD in paediatrics.

Antifungal Susceptibility Testing Practices at Acute Care Hospitals Enrolled in the National Healthcare Safety Network, United States, 2011-2015

We assessed availability of antifungal susceptibility testing (AFST) at nearly 4000 acute care hospitals enrolled in the National Healthcare Safety Network. In 2015, 95% offered any AFST, 28% offered AFST at their own laboratory or at an affiliated medical center, and 33% offered reflexive AFST. Availability of AFST improved from 2011 to 2015, but substantial gaps exist in the availability of AFST.

Candida auris: a worrisome, globally emerging pathogen

INTRODUCTION

Candida auris is a recently discovered, rapidly emerging fungal pathogen. Infections due to C. auris are hospital-acquired, multidrug resistant and associated with high mortality. Areas covered: This review highlights epidemiology, pathogenesis, microbiological characteristics, clinical presentation, diagnostic challenges and treatment options of C. auris infections. Infection prevention measures to prevent spread of C. auris and special measures during an outbreak situation have also been reviewed. Expert commentary: Rapid emergence of hospital onset C. auris is worrisome. Early diagnosis of C. auris is essential for better outcomes and the implementation of infection prevention measures. Lack of widespread awareness, absence of general availability of diagnostic testing methods, and limited options for treatment of C. auris infections make it a difficult-to-treat pathogen. Further studies are needed for better understanding of this emerging pathogen.

Differential Activity of the Oral Glucan Synthase Inhibitor SCY-078 against Wild-Type and Echinocandin-Resistant Strains of Candida Species

SCY-078 (formerly MK-3118) is a novel orally active inhibitor of fungal β-(1,3)-glucan synthase (GS). SCY-078 is a derivative of enfumafungin and is structurally distinct from the echinocandin class of antifungal agents. We evaluated the in vitro activity of this compound against wild-type (WT) and echinocandin-resistant isolates containing mutations in the FKS genes of Candida spp. Against 36 Candida spp. FKS mutants tested, 30 (83.3%) were non-WT to 1 or more echinocandins, and only 9 (25.0%) were non-WT (MIC, >WT-upper limit) to SCY-078. Among C. glabrata isolates carrying FKS alterations, 84.0% were non-WT to the echinocandins versus only 24.0% for SCY-078. In contrast to the echinocandin comparators, the activity of SCY-078 was minimally affected by the presence of FKS mutations, suggesting that this agent is useful in the treatment of Candida infections due to echinocandin-resistant strains.

An Immunomodulatory Peptide Confers Protection in an Experimental Candidemia Murine Model

Fungal Candida species are commensals present in the mammalian skin and mucous membranes. Candida spp. are capable of breaching the epithelial barrier of immunocompromised patients with neutrophil and cell-mediated immune dysfunctions and can also disseminate to multiple organs through the bloodstream. Here we examined the action of innate defense regulator 1018 (IDR-1018), a 12-amino-acid-residue peptide derived from bovine bactenecin (Bac2A): IDR-1018 showed weak antifungal and antibiofilm activity against a Candida albicans laboratory strain (ATCC 10231) and a clinical isolate (CI) (MICs of 32 and 64 μg · ml-1, respectively), while 8-fold lower concentrations led to dissolution of the fungal cells from preformed biofilms. IDR-1018 at 128 μg · ml-1 was not hemolytic when tested against murine red blood cells and also has not shown a cytotoxic effect on murine monocyte RAW 264.7 and primary murine macrophage cells at the tested concentrations. IDR-1018 modulated the cytokine profile during challenge of murine bone marrow-derived macrophages with heat-killed C. albicans (HKCA) antigens by increasing monocyte chemoattractant protein 1 (MCP-1) and interleukin-10 (IL-10) levels, while suppressing tumor necrosis factor alpha (TNF-α), IL-1β, IL-6, and IL-12 levels. Mice treated with IDR-1018 at 10 mg · kg-1 of body weight had an increased survival rate in the candidemia model compared with phosphate-buffered saline (PBS)-treated mice, together with a diminished kidney fungal burden. Thus, IDR-1018 was able to protect against murine experimental candidemia and has the potential as an adjunctive therapy.

Candida and invasive mould diseases in non-neutropenic critically ill patients and patients with haematological cancer

Critically ill patients and patients with haematological cancer are HIV-negative populations at high risk of invasive fungal infections. In intensive-care units, candidaemia and intra-abdominal candidiasis predominate, but aspergillosis has emerged as a lethal, under-recognised cause of pneumonia. In patients with haematological malignancies or who have undergone stem-cell transplantations, pulmonary disease due to aspergillus and other mould diseases predominate. In this Series paper, we provide an update on risk assessment, new diagnostic strategies, and therapeutic approaches. New concepts have emerged for use of risk prediction rules and an evidence base now exists for inclusion of biomarkers (eg, galactomannan, 1,3-β-D-glucan, and PCR assays for Aspergillus spp) into early diagnostic and therapeutic strategies. Imaging techniques remain helpful for early diagnosis of pulmonary mould diseases, with PET techniques offering potential improvements in diagnostic specificity and evaluation of clinical response. Echinocandins and triazoles have been validated extensively for prophylaxis, empirical therapy, and targeted therapy, but an increase in intrinsically resistant fungi and emergence of secondary resistance as a result of drug-induced selection pressure are of major concern. Echinocandins remain a major component of treatment of invasive candidiasis and new triazoles are the best alternative for prophylaxis and therapy of invasive aspergillosis.

Update on childhood and adult infectious tracheitis

The trachea is a pivotal organ of the respiratory tract. Rather than a genuine anatomic border, it acts as a crossroad in all respiratory infectious processes. Even though not strictly limited to the trachea, infections such as laryngotracheitis and tracheobronchitis are frequently diagnosed in children, in particular during the winter season. Infectious tracheitis etiologies are diverse and the distinction between viral and bacterial origins, albeit difficult, remains relevant considering the substantial differences in terms of gravity and therapeutic management. This literature review summarizes the microbiological and clinical aspects of community-acquired and nosocomial tracheitis in adults and children, as well as the adequate diagnostic and therapeutic approaches. It also highlights the emergence of fungal tracheitis in immunocompromised patients, of ventilator-associated tracheitis in intensive care medicine, and beyond all that the potential short and long-term consequences of tracheitis.

Association Between Candiduria and Candidemia: A Clinical and Molecular Analysis of Cases

The risk of developing candidemia after candiduria is reportedly very low, but it has not been adequately investigated. The aim of this study was to examine the molecular relatedness between Candida strains isolated from adult patients with candidemia and concomitant candiduria in association with the clinical characteristics of the cases. All episodes of candidemia occurring in a tertiary care academic hospital during a 5-year period were recorded prospectively. Patients with episodes of candiduria occurring two weeks preceding to or one week following a positive for Candida blood culture were included in the study. The genotypic relatedness of Candida strains isolated from blood and urine was investigated by pulsed-field gel electrophoresis after digestion with the BssHII restriction endonuclease. We recorded 141 candidemia episodes, occurring in 134 patients. Twelve episodes of candidemia with concomitant candiduria occurred in 11 patients (8% of all candidemias). In six of these episodes, the strains in the blood-urine pairs belonged to different species. In two episodes, the isolates belonged to the same species but were not genetically related, and only in four (2.8% of all candidemias), the strains were related. All four patients were severely ill and had multiple risk factors for candidemia. These findings indicate that in hospitalized patients with candidemia, concomitant candiduria is rare and usually an independent event, confirming previous reports. In the critically ill, however, the existence of genetically related strains in blood and urine appears to be more frequent, with more probable the hematogenous dissemination.

2016 guidelines for the use of antifungal agents in patients with invasive fungal diseases in Taiwan

The Infectious Diseases Society of Taiwan, Medical Foundation in Memory of Dr. Deh-Lin Cheng, Foundation of Professor Wei-Chuan Hsieh for Infectious Diseases Research and Education, and CY Lee's Research Foundation for Pediatric Infectious Diseases and Vaccines have updated the guidelines for the use of antifungal agents in adult patients with invasive fungal diseases in Taiwan. This guideline replaces the 2009 version. Recommendations are provided for Candida, Cryptococcus, Aspergillus and Mucormycetes. The focus is based on up-to-date evidence on indications for treatment or prophylaxis of the most common clinical problems. To support the recommendations in this guideline, the committee considered the rationale, purpose, local epidemiology, and key clinical features of invasive fungal diseases to select the primary and alternative antifungal agents. This is the first guideline that explicitly describes the quality and strength of the evidence to support these recommendations. The strengths of the recommendations are the quality of the evidence, the balance between benefits and harms, resource and cost. The guidelines are not intended nor recommended as a substitute for bedside judgment in the management of individual patients, the advice of qualified health care professionals, and more recent evidence concerning therapeutic efficacy and emergence of resistance. Practical considerations for individualized selection of antifungal agents include patient factors, pathogen, site of infection and drug-related factors, such as drug-drug interaction, drug-food intervention, cost and convenience. The guidelines are published in the Journal of Microbiology, Immunology and Infection and are also available on the Society website.

Etest and Sensititre YeastOne Susceptibility Testing of Echinocandins against Candida Species from a Single Center in Austria

Candida species were tested for susceptibility to caspofungin, anidulafungin, and micafungin in order to evaluate the roles of Etest and Sensititre YeastOne in antifungal susceptibility testing for daily routines and to survey resistance. A total of 104 Candida species isolates detected from blood cultures were investigated. With EUCAST broth microdilution as the reference method, essential agreement (EA), categorical agreement (CA), very major errors (VME), major errors (ME), and minor (MIN) errors were assessed by reading MICs at 18, 24, and 48 h. By use of EUCAST broth microdilution and species-specific clinical breakpoints (CBPs), echinocandin resistance was not detected during the study period. Using EUCAST CBPs, MIC readings at 24 h for the Etest and Sensititre YeastOne resulted in CA levels of 99% and 93% for anidulafungin and 99% and 97% for micafungin. Using revised CLSI CBPs for caspofungin, CA levels were 92% and 99% for Etest and Sensititre YeastOne. The Etest proved an excellent, easy-to-handle alternative method for testing susceptibility to anidulafungin and micafungin. Due to misclassifications, the Etest is less suitable for testing susceptibility to caspofungin (8% of isolates falsely tested resistant). The CA levels of Sensititre YeastOne were 93% and 97% for anidulafungin and micafungin (24 h) by use of EUCAST CBPs and increased to 100% for both antifungals if CLSI CBPs were applied and to 100% and 99% if Sensititre YeastOne epidemiological cutoff values (ECOFFs) were applied. No one echinocandin could be demonstrated to be superior to another in vitro Since resistance was lacking among our Candida isolates, we cannot derive any recommendation from accurate resistance detection by the Etest and Sensititre YeastOne.

2016 guideline strategies for the use of antifungal agents in patients with hematological malignancies or hematopoietic stem cell transplantation recipients in Taiwan

The Infectious Diseases Society of Taiwan (IDST), the Hematology Society of Taiwan, the Taiwan Society of Blood and Marrow Transplantation, Medical Foundation in Memory of Dr. Deh-Lin Cheng, Foundation of Professor Wei-Chuan Hsieh for Infectious Diseases Research and Education, and CY Lee's Research Foundation for Pediatric Infectious Diseases and Vaccines cooperatively published this guideline for the use of antifungal agents in hematological patients with invasive fungal diseases (IFDs) in Taiwan. The guideline is the first one endorsed by IDST focusing on selection of antifungal strategies, including prophylaxis, empirical (or symptom-driven) and pre-emptive (or diagnostic-driven) strategy. We suggest a risk-adapted dynamic strategy and provide an algorithm to facilitate decision making in population level as well as for individual patient. Risk assessment and management accordingly is explicitly emphasized. In addition, we highlight the importance of diagnosis in each antifungal strategy among five elements of the antimicrobial stewardship (diagnosis, drug, dose, de-escalation and duration). The rationale, purpose, and key recommendations for the choice of antifungal strategy are summarized, with concise review of international guidelines or recommendation, key original articles and local epidemiology reports. We point out the interaction and influence between elements of recommendations and limitation of and gap between evidences and daily practice. The guideline balances the quality of evidence and feasibility of recommendation in clinical practice. Finally, this version introduces the concept of health economics and provides data translated from local disease burdens. All these contents hopefully facilitate transparency and accountability in medical decision-making, improvements in clinical care and health outcomes, and appropriateness of medical resource allocation.

Initial Treatment of Cancer Patients with Fluconazole-Susceptible Dose-Dependent Candida glabrata Fungemia: Better Outcome with an Echinocandin or Polyene Compared to an Azole?

The 28-day crude mortality rate in 68 cancer patients with fluconazole-susceptible dose-dependent Candida glabrata fungemia started on treatment (within 48 h after blood culture collection) with an echinocandin or liposomal amphotericin-B was better (30%) than those treated with azole monotherapy (52%) (P = 0.07). After adjusting for confounders, azole monotherapy also was associated with worse 28-day survival (hazard ratio, 3.8; P = 0.003).

Micafungin Plasma Levels Are Not Affected by Continuous Renal Replacement Therapy: Experience in Critically Ill Patients

Critically ill patients often experience acute kidney injury and the need for renal replacement therapy in the course of their treatment in an intensive care unit (ICU). These patients are at an increased risk for candidiasis. Although there have been several reports of micafungin disposition during renal replacement therapy, to this date there are no data describing the elimination of micafungin during high-dose continuous venovenous hemodiafiltration with modified AN69 membranes. The aim of this prospective open-label pharmacokinetic study was to assess whether micafungin plasma levels are affected by continuous hemodiafiltration in critical ill patients using the commonly employed AN69 membrane. A total of 10 critically ill patients with micafungin treatment due to suspected or proven candidemia were included in this trial. Prefilter/postfilter micafungin clearance was measured to be 46.0 ml/min (±21.7 ml/min; n = 75 individual time points), while hemofilter clearance calculated by the sieving coefficient was 0.0038 ml/min (±0.002 ml/min; n = 75 individual time points). Total body clearance was measured to be 14.0 ml/min (±7.0 ml/min; n = 12). The population area under the curve from 0 to 24 h (AUC_0-24) was calculated as 158.5 mg · h/liter (±79.5 mg · h/liter; n = 13). In spite of high protein binding, no dose modification is necessary in patients receiving continuous venovenous hemodiafiltration with AN69 membranes. A dose elevation may, however, be justified in certain cases. (This study has been registered at ClinicalTrials.gov under identifier NCT02651038.).

In vitro potency and fungicidal activity of CD101, a novel echinocandin, against recent clinical isolates of Candida spp

Candida infections vary in severity and manifestation. Common infections include invasive bloodstream infections among hospitalized/immunocompromised patients and vulvovaginal candidiasis among women. Echinocandins and azoles are commonly utilized to treat Candida infections, although echinocandin use has been restricted to indications amenable to once-daily IV administration. CD101, a novel echinocandin with a long plasma half-life and enhanced stability, is in development for once-weekly IV administration for the treatment of candidemia and invasive candidiasis. In this study, the MIC of CD101 and comparators against 500 recent clinical Candida isolates was determined per Clinical and Laboratory Standards Institute guidelines. For select isolates, the minimum fungicidal concentration (MFC; n=49) and time-kill (n=9) of CD101 and comparators was evaluated. The MIC_50/90s (μg/mL; n=100/species) for CD101, anidulafungin, fluconazole, and amphotericin B, respectively, were: C. albicans (0.008/0.03, 0.004/0.008, 0.25/4, 0.25/0.5), C. tropicalis (0.008/0.03, 0.004/0.015, 0.5/2, 0.5/1), C. parapsilosis (1/1, 0.5/2, 0.5/1, 0.5/1), C. glabrata (0.03/0.03, 0.03/0.03, 8/>32, 0.5/0.5), and C. krusei (0.03/0.03, 0.03/0.03, 32/>32, 1/1). CD101 MICs were comparable to anidulafungin and both maintained potency against fluconazole-resistant isolates. Against rare anidulafungin-resistant isolates, the MICs of CD101 and anidulafungin were elevated vs. anidulafungin-susceptible isolates. Similar to anidulafungin, CD101 was fungicidal with an MFC:MIC ratio ≤4 for 95% of evaluable isolates and resulted in 3-log killing by 24-48h for all isolates evaluated by time-kill. The potent fungicidal activity of CD101 highlights the potential clinical utility of CD101 IV for the treatment of invasive candidiasis and candidemia.

Cost-effectiveness analysis of anidulafungin vs fluconazole for the treatment of invasive candidiasis (IC) in Turkey

Anidulafungin has been shown to be non-inferior to, and possibly more efficacious, than fluconazole in treating patients with invasive candidiasis (IC). This study aimed to determine the cost-effectiveness of anidulafungin vs fluconazole for treatment of IC in the Turkish setting. A decision analytic model was constructed to depict downstream economic consequences of using anidulafungin or fluconazole for treatment of IC in the Turkish hospitals. Transition probabilities (ie treatment success, observed or indeterminate treatment failures) were obtained from a published randomised clinical trial. Cost inputs were from the latest Turkish resources. Data not available in the literature were estimated by expert panels. Sensitivity analyses were performed to assess the robustness of the model outcome. While anidulafungin [TL 17 171 (USD 4589)] incurred a higher total cost than fluconazole [TL 8233 (USD 2200) per treated patient, treatment with anidulafungin was estimated to save an additional 0.58 life-years, with an incremental cost-effectiveness ratio of TL 15 410 (USD 4118) per life-years saved. Drug acquisition cost and hospitalisation were the main cost drivers for anidulafungin and fluconazole arms respectively. The model findings were robust over a wide range of input variables except for anidulafungin drug cost. Anidulafungin appears to be a cost-effective therapy in treating IC from the Turkish hospital perspective.

Pharmacokinetics of antifungal drugs: practical implications for optimized treatment of patients

Introduction

Because of the high mortality of invasive fungal infections (IFIs), appropriate exposure to antifungals appears to be crucial for therapeutic efficacy and safety.

Materials and methods

This review summarises published pharmacokinetic data on systemically administered antifungals focusing on co-morbidities, target-site penetration, and combination antifungal therapy.

Conclusions and discussion

Amphotericin B is eliminated unchanged via urine and faeces. Flucytosine and fluconazole display low protein binding and are eliminated by the kidney. Itraconazole, voriconazole, posaconazole and isavuconazole are metabolised in the liver. Azoles are substrates and inhibitors of cytochrome P450 (CYP) isoenzymes and are therefore involved in numerous drug–drug interactions. Anidulafungin is spontaneously degraded in the plasma. Caspofungin and micafungin undergo enzymatic metabolism in the liver, which is independent of CYP. Although several drug–drug interactions occur during caspofungin and micafungin treatment, echinocandins display a lower potential for drug–drug interactions. Flucytosine and azoles penetrate into most of relevant tissues. Amphotericin B accumulates in the liver and in the spleen. Its concentrations in lung and kidney are intermediate and relatively low myocardium and brain. Tissue distribution of echinocandins is similar to that of amphotericin. Combination antifungal therapy is established for cryptococcosis but controversial in other IFIs such as invasive aspergillosis and mucormycosis.

The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections

Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in the emergency departments worldwide. The cornerstones of effective treatment of IAIs are early recognition, adequate source control, and appropriate antimicrobial therapy. Prompt resuscitation of patients with ongoing sepsis is of utmost important. In hospitals worldwide, non-acceptance of, or lack of access to, accessible evidence-based practices and guidelines result in overall poorer outcome of patients suffering IAIs. The aim of this paper is to promote global standards of care in IAIs and update the 2013 WSES guidelines for management of intra-abdominal infections.