Antifungal therapy and outcomes in infants with invasive Candida infections

Emerging Treatments in Neonatal Fungal Infections: Progress and Prospects

Fungal infections in neonates are potentially life threatening. The differential diagnosis for neonatal rashes is extensive, with common culprits including both bacteria and fungi. Candida albicans is the predominant fungal pathogen, causing infections that range from superficial disease to severe systemic conditions, including sepsis and meningitis. Neonates, especially those who are preterm, are particularly susceptible because of developmentally immature immune systems and the use of invasive procedures and devices in neonatal intensive care units. Congenital cutaneous candidiasis, acquired in utero or during delivery, can lead to disseminated infection with high mortality rates. Early diagnosis and prompt antifungal treatment are crucial but challenging because of subtle clinical presentations, making accurate identification of the offending organism essential for selecting the appropriate treatment. Candida species account for the majority of neonatal fungal infections, with different species necessitating distinct treatments because of varying susceptibility profiles. Aspergillus, another significant pathogen, poses high mortality risks and can present either cutaneously or systemically. Malassezia, though less common, primarily affects preterm infants with catheter-related fungemia. Other fungal species, including Zygomycetes, Trichosporon, and Cryptococcus, rarely produce neonatal infections but are noteworthy for consideration. Treatment of fungal infection is critical despite the relative paucity of information regarding the clinical pharmacology of many antifungal drugs in neonates. We review the major antifungal agents (e.g., amphotericin B, the echinocandins, the azoles) and provide pharmacologic and dosing information. Finally, preventive strategies, including the use of stringent aseptic techniques and careful clinical monitoring, are essential to mitigate both the incidence and severity of these infections in neonates and infants in the first months of life.

The Paediatric European Confederation of Medical Mycology (ECMM) Quality (Paed-EQUAL) Candida Score for the Management of Candidaemia in Children and Neonates

Candidaemia in children is associated with high mortality. The epidemiology of Candida bloodstream infection is changing with rising rates of fluconazole resistance worldwide and the emergence of novel multidrug-resistant species such as Candida auris, which is associated with outbreaks. Guidelines on the management of candidaemia emphasise identification of species and determination of antifungal susceptibility to guide appropriate treatment, performing relevant investigations to rule out deep-seated infection, and removal of central venous catheters. However, it is difficult to apply guidelines in routine practice. The European Confederation of Medical Mycology candidaemia scoring tool (the EQUAL score) has facilitated adherence to guidelines by using a point-based system. We have designed a point-based paediatric EQUAL (paed-EQUAL) score tool for the management of candidaemia in neonates and children. The paed-EQUAL scoring tool can be applied to improve guideline adherence and facilitate antifungal stewardship.

Recent Challenges in Diagnosis and Treatment of Invasive Candidiasis in Neonates

Invasive Candida infections represent a significant cause of morbidity and mortality in the neonatal intensive care unit (NICU), particularly among preterm and low birth weight neonates. The nonspecific clinical presentation of invasive candidiasis, resembling that of bacterial sepsis with multiorgan involvement, makes the diagnosis challenging. Given the atypical clinical presentation and the potential detrimental effects of delayed treatment, empirical treatment is often initiated in cases with high clinical suspicion. This underscores the need to develop alternative laboratory methods other than cultures, which are known to have low sensitivity and a prolonged detection time, to optimize therapeutic strategies. Serum biomarkers, including mannan antigen/anti-mannan antibody and 1,3-β-D-glucan (BDG), both components of the yeast cell wall, a nano-diagnostic method utilizing T2 magnetic resonance, and Candida DNA detection by PCR-based techniques have been investigated as adjuncts to body fluid cultures and have shown promising results in improving diagnostic efficacy and shortening detection time in neonatal populations. This review aims to provide an overview of the diagnostic tools and the current management strategies for invasive candidiasis in neonates. Timely and accurate diagnosis followed by targeted antifungal treatment can significantly improve the survival and outcome of neonates affected by Candida species.

Antibiotics, Analgesic Sedatives, and Antiseizure Medications Frequently Used in Critically Ill Neonates: A Narrative Review

Antibiotic, analgesic sedative, and antiseizure medications are among the most commonly used medications in preterm/sick neonates, who are at high risk of nosocomial infections, central nervous system complications, and are exposed to numerous painful/stressful procedures. These severe and potentially life-threatening complications may have serious short- and long-term consequences and should be prevented and/or promptly treated. The reported variability in the medications used in neonates indicates the lack of adequate neonatal studies regarding their effectiveness and safety. Important obstacles contributing to inadequate studies in preterm/sick infants include difficulties in obtaining parental consent, physicians' unwillingness to recruit preterm infants, the off-label use of many medications in neonates, and other scientific and ethical concerns. This review is an update on the use of antimicrobials (antifungals), analgesics (sedatives), and antiseizure medications in neonates, focusing on current evidence or knowledge gaps regarding their pharmacokinetics, indications, safety, dosage, and evidence-based guidelines for their optimal use in neonates. We also address the effects of early antibiotic use on the intestinal microbiome and its association with long-term immune-related diseases, obesity, and neurodevelopment (ND). Recommendations for empirical treatment and the emergence of pathogen resistance to antimicrobials and antifungals are also presented. Finally, future perspectives on the prevention, modification, or reversal of antibiotic resistance are discussed.

Updates in the Pharmacologic Prophylaxis and Treatment of Invasive Candidiasis in the Pediatric and Neonatal Intensive Care Units

Purpose of review

The goal of this review was to provide an update on the prevention and treatment options for invasive candidiasis (IC) in the neonatal intensive care unit (NICU) and pediatric intensive care unit (PICU).

Recent findings

Studies have further validated the use of fluconazole for IC prophylaxis among high-risk patients in the NICU. It remains unclear if prophylaxis leads to resistance development and the ideal dosage regimen is still not clear. Recent studies have been published comparing caspofungin and micafungin to amphotericin B and illustrated similar efficacy outcomes in the NICU. Micafungin now has approval from the United States Food and Drug Administration (FDA) for use in infants < 4 months of age. Prophylactic strategies in the PICU could include zinc and vitamin D. Anidulafungin has recent non-comparative data supporting use in pediatric patients older than 1 month of age and also has a recent FDA approval for use in children 1 month of age and older.

Summary

Fluconazole prophylaxis remains a reasonable strategy in select NICU patients, although further analyses of resistance and the optimal dosage regimen are needed. Echinocandins are potential therapeutic options for non-meningitis or urinary tract infections in both the neonatal and pediatric population.

Neonatal invasive candidiasis: updates on clinical management and prevention

Neonatal invasive candidiasis is an important cause of morbidity and mortality in preterm infants. The incidence of invasive candidiasis in this population has been declining in high-income settings, largely due to preventive measures, although there are still considerable variations in incidence between health-care centres. Surveillance data and large, multicentre studies in lower-income settings are not available, although preventive measures in these settings have been shown to decrease the incidence of neonatal invasive candidiasis. Understanding risk factors and pathogenesis are key to the prevention of invasive candidiasis. The difficulty of a definitive diagnosis of invasive candidiasis and the high risk for death or substantial neurodevelopmental impairment, even with appropriate treatment, further increase the need for effective preventive measures. In this Review, we examine the pathogenesis, clinical presentation, and diagnosis of invasive candidiasis. We highlight commonly used and emerging preventive and prophylactic measures, including standardised central line care, antibiotic stewardship, antifungal prophylaxis, and probiotics. Finally, we provide updates on empirical treatment, clinical management in confirmed cases of invasive candidiasis, and antifungal pharmacotherapy.

High-Dose Micafungin in Neonates and Young Infants with Invasive Candidiasis: Results of a Phase 2 Study

Limited data are available on the most appropriate dosing, efficacy, and safety of micafungin in neonates and young infants with invasive candidiasis (IC). This study evaluated plasma levels, efficacy, and safety of micafungin at a dose of 8 mg/kg daily for a mean of 13.3 days (±5.2 days) in 35 neonates and young infants with IC. Micafungin plasma concentrations were 5.70 mg/liter preadministration and 17.23, 15.59, and 10.27 mg/liter after 1, 2, and 8 h, respectively. The resolution of the infection was achieved in 86.7% of patients treated for ≥14 days. In 20.0% of patients, we observed a transient hypertransaminasemia. Micafungin at a dose of 8 mg/kg daily is effective and well tolerated in neonates and young infants with IC. (This study has been registered at ClinicalTrials.gov under identifier NCT03421002 and in the EU Clinical Trials Register under number 2014-003087-20.).

Review of Fluconazole Treatment and Prophylaxis for Invasive Candidiasis in Neonates

Invasive candidiasis accounts for approximately 10% of nosocomial infections in preterm infants, with an incidence of 1% to 4% among neonatal intensive care unit (NICU) admissions and a mortality as high as 20% to 30%. These outcomes warrant improved treatment and prevention strategies for infants at highest risk. The Infectious Diseases Society of America provides guidelines on antifungal medications for the prophylaxis and treatment of candidiasis in NICUs; however, there are still variations in practice on the use of fluconazole for prophylaxis and treatment of invasive candidiasis. This review provides specific information regarding fluconazole activity, pharmacokinetics, and a literature evaluation of dosing strategies and comparisons to other treatments in the neonatal population.

Trends in Pediatric Candidemia: Epidemiology, Anti-Fungal Susceptibility, and Patient Characteristics in a Children's Hospital

Candida bloodstream infections (CBSIs) have decreased among pediatric populations in the United States, but remain an important cause of morbidity and mortality. Species distributions and susceptibility patterns of CBSI isolates diverge widely between children and adults. The awareness of these patterns can inform clinical decision-making for empiric or pre-emptive therapy of children at risk for candidemia. CBSIs occurring from 2006-2016 among patients in a large children's hospital were analyzed for age specific trends in incidence rate, risk factors for breakthrough-CBSI, and death, as well as underlying conditions. Candida species distributions and susceptibility patterns were evaluated in addition to the anti-fungal agent use. The overall incidence rate of CBSI among this complex patient population was 1.97/1000 patient-days. About half of CBSI episodes occurred in immunocompetent children and 14% in neonatal intensive care unit (NICU) patients. Anti-fungal resistance was minimal: 96.7% of isolates were fluconazole, 99% were micafungin, and all were amphotericin susceptible. Liposomal amphotericin was the most commonly prescribed anti-fungal agent included for NICU patients. Overall, CBSI-associated mortality was 13.7%; there were no deaths associated with CBSI among NICU patients after 2011. Pediatric CBSI characteristics differ substantially from those in adults. The improved management of underlying diseases and antimicrobial stewardship may further decrease morbidity and mortality from CBSI, while continuing to maintain low resistance rates among Candida isolates.

[Bloodstream infections with Candida glabrata in a neonatal intensive care unit that uses prophylaxis with fluconazole]

BACKGROUND

Candida glabrata is an emerging pathogen with the ability to develop tolerance and resistance to azole antifungals, which creates uncertainty about the usefulness of antifungal prophylaxis in newborns.

AIMS

The aim of this study was to describe the factors associated with C. glabrata infection in a NICU that uses prophylaxis with fluconazole.

METHODS

A case-control study paired by gestational age was designed and conducted at the Civil Hospital of Guadalajara Dr. Juan I. Menchaca. Newborns with C. glabrata infection were studied and for each one a matched control was selected by gestational age. Odds ratios (OR) were estimated with 95% confidence intervals (95% CI) and McNemar test for contrast of hypothesis was applied.

RESULTS

Twenty-one infected patients were identified, from whom 66.7% were male; the median gestational age was 31.5 weeks. Increased risk of infection with C. glabrata was observed when there was a prescription of more than one antimicrobial scheme (OR 21, 95% CI, 1.23 - 358.3; p=0.006) and also among patients with surgical comorbidities (OR 8, 95% CI 1.01 - 63.9; p=0.04). During the study period, exposure to fluconazole showed no difference in the risk of infection.

CONCLUSIONS

Neonates with more than one antimicrobial regimen and those with surgical comorbidities had a higher risk of C. glabrata infection.

Nephrotoxic medications and acute kidney injury risk factors in the neonatal intensive care unit: clinical challenges for neonatologists and nephrologists

Neonatal acute kidney injury (AKI) is common. Critically ill neonates are at risk for AKI for many reasons including the severity of their underlying illnesses, prematurity, and nephrotoxic medications. In this educational review, we highlight four clinical scenarios in which both the illness itself and the medications indicated for their treatment are risk factors for AKI: sepsis, perinatal asphyxia, patent ductus arteriosus, and necrotizing enterocolitis. We review the available evidence regarding medications commonly used in the neonatal period with known nephrotoxic potential, including gentamicin, acyclovir, indomethacin, vancomycin, piperacillin-tazobactam, and amphotericin. We aim to illustrate the complexity of decision-making involved for both neonatologists and pediatric nephrologists when managing infants with these conditions and advocate for ongoing multidisciplinary collaboration in the development of better AKI surveillance protocols and AKI mitigation strategies to improve care for these vulnerable patients.

Administration and Dosing of Systemic Antifungal Agents in Pediatric Patients

Neonates and immunosuppressed/immunocompromised pediatric patients are at high risk of invasive fungal diseases. Appropriate antifungal selection and optimized dosing are imperative to the successful prevention and treatment of these life-threatening infections. Conventional amphotericin B was the mainstay of antifungal therapy for many decades, but dose-limiting nephrotoxicity and infusion-related adverse events impeded its use. Despite the development of several new antifungal classes and agents in the past 20 years, and their now routine use in at-risk pediatric populations, data to guide the optimal dosing of antifungals in children are limited. This paper reviews the spectra of activity for approved antifungal agents and summarizes the current literature specific to pediatric patients regarding pharmacokinetic/pharmacodynamic data, dosing, and therapeutic drug monitoring.

Neonatal Antifungal Consumption Is Dominated by Prophylactic Use; Outcomes From The Pediatric Antifungal Stewardship: Optimizing Antifungal Prescription Study

BACKGROUND

Diagnostic challenges combined with the vulnerability of neonates to develop invasive candidiasis (IC) may lead to antifungal administration in the absence of IC. A modified point-prevalence study was performed to obtain an improved insight and understanding of antifungal prescribing in this specific patient population.

METHODS

Neonates and infants ≤90 days of age receiving systemic antifungals from 12 centers in England were included. Data were collected prospectively during 26 consecutive weeks and entered into an online REDCap database.

RESULTS

Two hundred eighty neonates and infants were included, the majority ≤1 month of age (68.2%). Prematurity was the commonest underlying condition (68.9%). Antifungals were prescribed for prophylactic reason in 79.6%; of those, 64.6% and 76.3% were extreme low birth weight infants and prematurely born neonates, respectively. Additional risk factors were present in almost all patients, but only 44.7% had ≥3 risk factors rendering them more susceptible to develop IC. Nonpremature and non extremely low birth weight premature infants only scored ≥3 risk factors in 32.6% and 15%, respectively. Fluconazole was the most common antifungal used (76.7% of all prescriptions), and commonly underdosed as treatment. The number of microbiologic proven IC was low, 5.4%.

CONCLUSIONS

Neonatal antifungal prophylaxis is commonly prescribed outside the recommendations based on known risk profiles. Fluconazole is the main antifungal prescribed in neonates and infants, with underdosing frequently observed when prescribed for treatment. Number of proven IC was very low. These observations should be taken into consideration to develop a national pediatric Antifungal Stewardship program aiming to guide rational prescribing.

A Phase 3 Study of Micafungin Versus Amphotericin B Deoxycholate in Infants With Invasive Candidiasis

BACKGROUND

Amphotericin B deoxycholate (AmB-D) is standard of care treatment for neonatal invasive candidiasis (IC). Micafungin (MCA) has broad-spectrum fungicidal activity against Candida spp. We compared the efficacy and safety of intravenous MCA with intravenous AmB-D and assessed the pharmacokinetics of MCA in infants >2-120 days of age with proven IC in a phase 3, randomized, double-blind, multicenter, parallel-group, noninferiority study (NCT00815516).

METHODS

Infants were randomized 2:1 to MCA (10 mg/kg/d) or AmB-D (1 mg/kg/d) for ≥21 days. Primary efficacy endpoint was fungal-free survival (FFS) 1 week after last study drug dose. MCA population pharmacokinetics included simulated area under the curve (AUC) at steady state and maximum plasma concentration after 2-hour infusion. AUC pharmacodynamic target exposure was 170 µg·h/mL.

RESULTS

Thirty infants received MCA (n = 20) or AmB-D (n = 10). The trial was terminated early because of slow recruitment. FFS was observed in 12 of 20 [60%; 95% confidence interval (CI): 36%-81%] MCA-group infants and in 7 of 10 (70%; 95% CI: 35%-93%) AmB-D-group infants. The most common treatment-emergent adverse events were anemia [MCA: n = 9 (45%); AmB-D: n = 3 (30%)] and thrombocytopenia [n = 2 (10%) and n = 3 (30%), respectively]. Model-derived mean AUC at steady state for MCA was 399.3 ± 163.9 µg·h/mL (95% prediction interval: 190.3-742.3 µg/mL); steady state and maximum plasma concentration after 2-hour infusion was 31.1 ± 10.5 µg/mL (95% prediction interval: 17.0-49.7 µg/mL). MCA exposures were above the AUC pharmacodynamic target exposure.

CONCLUSIONS

Within the study limitations, infants with IC treated with MCA achieved similar FFS compared with AmB-D. Both agents were safe and well tolerated.

Comprehensive drug utilization review in neonates: liposomal amphotericin B

Objectives

This drug utilization evaluation aims to review current evidence on safety and efficacy of using liposomal amphotericin B (LAMB) in newborns with candidiasis, and compare it to the conventional preparation. Conventional amphotericin B deoxycholate (DAMB) is more commonly used in newborns, but dose-limiting adverse effects may compromise its efficacy. This review will examine the advantages and disadvantages of liposomal amphotericin B and define its place in current practice.

Key Findings

The terms ‘AmBisome’ or ‘liposomal amphotericin B’ and ‘neonatal candidiasis’ were entered in both PubMed and Ovid; studies included focused on safety and efficacy of liposomal amphotericin B in newborns with candidiasis, as well as studies comparing the conventional and the liposomal formulations in newborns as monotherapy. Pertinent references obtained from this search were also included. Additionally, pharmacokinetic studies were reviewed to include available data on dosing. Single case reports were not included in the review due to the limited conclusions that can be drawn from such sample sizes and quality of data.

Summary

Although liposomal amphotericin B may be better tolerated and as efficacious as the conventional formulation based on the published literature, the weakness of the studies available on the subject cannot be overlooked. Additional randomized controlled trials are needed to determine the true benefits of this medication.

Safety, dosing, and pharmaceutical quality for studies that evaluate medicinal products (including biological products) in neonates

The study of medications among pediatric patients has increased worldwide since 1997 in response to new legislation and regulations, but these studies have not yet adequately addressed the therapeutic needs of neonates. Additionally, extant guidance developed by regulatory agencies worldwide does not fully address the specificities of neonatal drug development, especially among extremely premature newborns who currently survive. Consequently, an international consortium from Canada, Europe, Japan, and the United States was organized by the Critical Path Institute to address the content of guidance. This group included neonatologists, neonatal nurses, parents, regulators, ethicists, clinical pharmacologists, specialists in pharmacokinetics, specialists in clinical trials and pediatricians working in the pharmaceutical industry. This group has developed a comprehensive, referenced White Paper to guide neonatal clinical trials of medicines - particularly early phase studies. Key points include: the need to base product development on neonatal physiology and pharmacology while making the most of knowledge acquired in other settings; the central role of families in research; and the value of the whole neonatal team in the design, implementation and interpretation of studies. This White Paper should facilitate successful clinical trials of medicines in neonates by informing regulators, sponsors, and the neonatal community of existing good practice.

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

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Review on fungal enzyme inhibitors – potential drug targets to manage human fungal infections

The potential applications of enzyme inhibitors for the management of invasive fungal infections are explored.

Prophylactic systemic antifungal agents to prevent mortality and morbidity in very low birth weight infants

BACKGROUND

Invasive fungal infection is an important cause of mortality and morbidity in very preterm and very low birth weight infants. Early diagnosis is difficult and treatment is often delayed. Systemically absorbed antifungal agents (usually azoles) are increasingly used as prophylaxis against invasive fungal infection in this population.

OBJECTIVES

To assess the effect of prophylactic systemic antifungal therapy on mortality and morbidity in very preterm or very low birth weight infants.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 8), MEDLINE, EMBASE, and CINAHL (to May 2015), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised controlled trials that compared the effect of prophylactic systemic antifungal therapy versus placebo or no drug or another antifungal agent or dose regimen in very low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of trial quality and data extraction by two review authors.

MAIN RESULTS

We identified 15 eligible trials enrolling a total of 1690 infants. Ten trials (1371 infants) compared systemic antifungal prophylaxis versus placebo or no drug. These trials were generally of good methodological quality. Meta-analysis found a statistically significant reduction in the incidence of invasive fungal infection (typical risk ratio (RR) 0.43, 95% confidence interval (CI) 0.31 to 0.59; risk difference (RD) -0.09, 95% CI -0.12 to -0.06). The average incidence of invasive fungal infection in the control groups of the trials (16%) was much higher than that generally reported from large cohort studies. Meta-analysis did not find a statistically significant difference in the risk of death prior to hospital discharge (typical RR 0.79, 95% CI 0.61 to 1.02; typical RD -0.04, 95% CI -0.07 to 0.00). Very limited data on long-term neurodevelopmental outcomes were available. Three trials that compared systemic versus oral or topical non-absorbed antifungal prophylaxis did not detect any statistically significant effects on invasive fungal infection or mortality. Two trials that compared different dose regimens of prophylactic intravenous fluconazole did not detect any significant differences in infection rates or mortality.

AUTHORS' CONCLUSIONS

Prophylactic systemic antifungal therapy reduces the incidence of invasive fungal infection in very preterm or very low birth weight infants. This finding should be interpreted and applied cautiously since the incidence of invasive fungal infection was very high in the control groups of many of the included trials. Meta-analysis does not demonstrate a statistically significant effect on mortality. There are currently only limited data on the long-term neurodevelopmental consequences for infants exposed to this intervention. In addition, there is a need for further data on the effect of the intervention on the emergence of organisms with antifungal resistance.

Prophylactic oral/topical non-absorbed antifungal agents to prevent invasive fungal infection in very low birth weight infants

BACKGROUND

Invasive fungal infection is an important cause of mortality and morbidity in very preterm or very low birth weight infants. Uncertainty exists about the effect of prophylactic oral/topical non-absorbed antifungals to reduce mucocutaneous colonisation and so limit the risk of invasive fungal infection in this population.

OBJECTIVES

To assess the effect of prophylactic oral/topical non-absorbed antifungal therapy on the incidence of invasive fungal infection, mortality and morbidity in very preterm or very low birth weight infants.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (CENTRAL: The Cochrane Library, 2015, Issue 7), MEDLINE, EMBASE, and CINAHL (to May 2015), conference proceedings, and previous reviews.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised controlled trials that compared the effect of prophylactic oral/topical non-absorbed antifungal therapy versus placebo or no drug or another antifungal agent or dose regimen in very preterm or very low birth weight infants.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the Cochrane Neonatal Review Group with separate evaluation of trial quality and data extraction by two review authors.

MAIN RESULTS

Four trials, in which a total of 1800 infants participated, compared oral/topical non-absorbed antifungal prophylaxis (nystatin or miconazole) with placebo or no drug. These trials had various methodological weaknesses including quasi-randomisation, lack of allocation concealment, and lack of blinding of intervention and outcomes assessment. The incidence of invasive fungal infection was very high in the control groups of three of these trials. Meta-analysis found a statistically significant reduction in the incidence of invasive fungal infection (typical risk ratio 0.20, 95% confidence interval 0.14 to 0.27; risk difference -0.18, -0.21 to -0.15) but substantial statistical heterogeneity was present. We did not find a statistically significant effect on mortality (typical risk ratio 0.87, 0.72 to 1.05; risk difference -0.03, -0.06 to 0.01). None of the trials assessed posthospital discharge outcomes. Three trials (N = 326) assessed the effect of oral/topical non-absorbed versus systemic antifungal prophylaxis. Meta-analyses did not find any statistically significant differences in the incidences of invasive fungal infection or all-cause mortality.

AUTHORS' CONCLUSIONS

The finding of a reduction in risk of invasive fungal infection in very low birth weight infants treated with oral/topical non-absorbed antifungal prophylaxis should be interpreted cautiously because of methodological weaknesses in the included trials. Further large randomised controlled trials in current neonatal practice settings are needed to resolve this uncertainty. These trials might compare oral/topical non-absorbed antifungal agents with placebo, with each other, or with systemic antifungal agents and should include an assessment of effect on long-term neurodevelopmental outcomes.

Advances in the treatment of invasive neonatal candidiasis

INTRODUCTION

Invasive candidiasis is responsible for ∼ 10% of nosocomial sepsis in very-low-birth-weight infants and is associated with substantial morbidity and mortality. Over the last two decades, the antifungal armamentarium against Candida spp. has increased; however, efficacy and safety studies in this population are lacking.

AREAS COVERED

We reviewed the medical literature and extracted information on clinical and observational studies evaluating the use of antifungal agents in neonates with invasive candidiasis.

EXPERT OPINION

Efficacy and safety data for antifungals in neonates are lacking, and the majority of studies conducted to date have concentrated on pharmacokinetic/pharmacodynamic evaluations. Unlike other anti-infective agents, efficacy data in the setting of neonatal candidiasis cannot be extrapolated from adult studies due to differences in the pathophysiology of the disease in this population relative to older children and adults. Data for amphotericin B deoxycholate, fluconazole, and micafungin suggest that these are the current agents of choice for this disease in neonates until data for newer antifungal agents become available. For prophylaxis, data from fluconazole randomized controlled trials will be submitted to the regulatory agencies for labeling. Ultimately, the field of therapeutics for neonatal candidiasis will require multidisciplinary collaboration given the numerous challenges associated with conducting clinical trials in neonates.

Neonatal candidiasis: diagnosis, prevention, and treatment

Infection with Candida species is associated with significant morbidity and mortality in infants. The incidence of Candida infection varies widely across centers, likely due to differences in practice related to modifiable risk factors such as exposure to empiric antibiotics and length of parenteral nutrition. Early diagnosis of Candida and prompt treatment with appropriate antifungal agents, such as fluconazole, amphotericin B deoxycholate, and micafungin, are critical for improved outcomes. This paper reviews the current literature relating to the prevention, diagnosis, and treatment of Candida infections in the neonatal intensive care unit.

Renal handling of amphotericin B and amphotericin B-deoxycholate and potential renal drug-drug interactions with selected antivirals

Amphotericin B (AmB) is excreted via the renal excretion route. This excretion process may result in nephrotoxicity. However, relevant information on the precise renal excretion mechanisms is not available. The aim of the study was to analyze the possible interaction of AmB or its prodrug AmB deoxycholate (AmB-DOC) with the typical renal organic anion transporters (OATs) and organic cation transporters (OCTs), using cellular and organ models. The relevant transport systems were then investigated in terms of the drug-drug interactions of AmB-DOC with antivirals that might potentially be used concomitantly. To analyze the renal excretion mechanisms of [(3)H]AmB, perfused rat kidney was employed. HeLa and MDCK II cells transiently transfected with human OAT1 (hOAT1) or hOCT2 were used as the cellular models. A significant tubular secretion of AmB was demonstrated in the perfused rat kidney. The cellular studies performed confirmed the active transport of AmB into cells. AmB did not interact with hOAT1 but strongly inhibited hOCT2. In contrast, AmB-DOC inhibited both hOAT1 and hOCT2. However, [(3)H]AmB cellular uptake by hOAT1 and hOCT2 was not found. AmB-DOC interacted significantly with adefovir, tenofovir, and cidofovir in hOAT1-transfected cells at supratherapeutic concentrations. In conclusion, the significant potency of AmB and AmB-DOC for inhibiting the transporters was demonstrated in this study. The secretion of AmB in the renal tubules is likely not related to the transporters here, since the drug was not proven to be a substrate for them. Drug-drug interactions of AmB and the antivirals used in this study on the investigated transporters are not probable.

Invasive candidiasis in low birth weight preterm infants: risk factors, clinical course and outcome in a prospective multicenter study of cases and their matched controls

Background

This multicenter prospective study of invasive candidiasis (IC) was carried out to determine the risk factors for, incidence of, clinical and laboratory features, treatment and outcome of IC in infants of birth weight <1250 g.

Methods

Neonates <1250 g with IC and their matched controls (2:1) were followed longitudinally and descriptive analysis was performed. Survivors underwent neurodevelopmental assessment at 18 to 24 months corrected age. Neurodevelopmental impairment (NDI) was defined as blindness, deafness, moderate to severe cerebral palsy, or a score <70 on the Bayley Scales of Infant Development 2nd edition. Multivariable analyses were performed to determine risk factors for IC and predictors of mortality and NDI.

Results

Cumulative incidence rates of IC were 4.2%, 2.2% and 1.5% for birth-weight categories <750 g, <1000 g, <1500 g, respectively. Forty nine infants with IC and 90 controls were enrolled. Necrotizing enterocolitis (NEC) was the only independent risk factor for IC (p = 0.03). CNS candidiasis occurred in 50% of evaluated infants, while congenital candidiasis occurred in 31%. Infants with CNS candidiasis had a higher mortality rate (57%) and incidence of deafness (50%) than the overall cohort of infants with IC. NDI (56% vs. 33%; p = 0.017) and death (45% vs. 7%; p = 0.0001) were more likely in cases than in controls, respectively. IC survivors were more likely to be deaf (28% vs. 7%; p = 0.01). IC independently predicted mortality (p = 0.0004) and NDI (p = 0.018).

Conclusion

IC occurred in 1.5% of VLBW infants. Preceding NEC increased the risk of developing IC. CNS candidiasis is under-investigated and difficult to diagnose, but portends a very poor outcome. Mortality, deafness and NDI were independently significantly increased in infants with IC compared to matched controls.

Early-onset neonatal sepsis

Early-onset sepsis remains a common and serious problem for neonates, especially preterm infants. Group B streptococcus (GBS) is the most common etiologic agent, while Escherichia coli is the most common cause of mortality. Current efforts toward maternal intrapartum antimicrobial prophylaxis have significantly reduced the rates of GBS disease but have been associated with increased rates of Gram-negative infections, especially among very-low-birth-weight infants. The diagnosis of neonatal sepsis is based on a combination of clinical presentation; the use of nonspecific markers, including C-reactive protein and procalcitonin (where available); blood cultures; and the use of molecular methods, including PCR. Cytokines, including interleukin 6 (IL-6), interleukin 8 (IL-8), gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α), and cell surface antigens, including soluble intercellular adhesion molecule (sICAM) and CD64, are also being increasingly examined for use as nonspecific screening measures for neonatal sepsis. Viruses, in particular enteroviruses, parechoviruses, and herpes simplex virus (HSV), should be considered in the differential diagnosis. Empirical treatment should be based on local patterns of antimicrobial resistance but typically consists of the use of ampicillin and gentamicin, or ampicillin and cefotaxime if meningitis is suspected, until the etiologic agent has been identified. Current research is focused primarily on development of vaccines against GBS.

Pharmacokinetics and pharmacodynamics of antifungals in children: clinical implications

Invasive fungal disease (IFD) remains life threatening in premature infants and immunocompromised children despite the recent development of new antifungal agents. Optimal dosing of antifungals is one of the few factors clinicians can control to improve outcomes of IFD. However, dosing in children cannot be extrapolated from adult data because IFD pathophysiology, immune response, and drug disposition differ from adults. We critically examined the literature on pharmacokinetics (PK) and pharmacodynamics (PD) of antifungal agents and highlight recent developments in treating pediatric IFD. To match adult exposure in pediatric patients, dosing adjustment is necessary for almost all antifungals. In young infants, the maturation of renal and metabolic functions occurs rapidly and can significantly influence drug exposure. Fluconazole clearance doubles from birth to 28 days of life and, beyond the neonatal period, agents such as fluconazole, voriconazole, and micafungin require higher dosing than in adults because of faster clearance in children. As a result, dosing recommendations are specific to bracketed ranges of age. PD principles of antifungals mostly rely on in vitro and in vivo models but very few PD studies specifically address IFD in children. The exposure-response relationship may differ in younger children compared with adults, especially in infants with invasive candidiasis who are at higher risk of disseminated disease and meningoencephalitis, and by extension severe neurodevelopmental impairment. Micafungin is the only antifungal agent for which a specific target of exposure was proposed based on a neonatal hematogenous Candida meningoencephalitis animal model. In this review, we found that pediatric data on drug disposition of newer triazoles and echinocandins are lacking, dosing of older antifungals such as fluconazole and amphotericin B products still need optimization in young infants, and that target PK/PD indices need to be clinically validated for almost all antifungals in children. A better understanding of age-specific PK and PD of new antifungals in infants and children will help improve clinical outcomes of IFD by informing dosing and identifying future research areas.

Neonatal invasive fungal infection in England 2004-2010

Rates of invasive fungal infection are highest among neonates, especially those of low birthweight. This study aimed to describe the current epidemiology of invasive neonatal fungal infections in a UK neonatal infection surveillance network. From 2004 to 2010 prospective multicentre surveillance was conducted by 14 neonatal units using a web-based database. Clinicians then completed a standardized pro forma for each positive fungal blood and/or cerebrospinal fluid culture. The overall incidence was 2.4/1000 neonatal unit admissions and was highest among babies <1000 g (extreme low birthweight, 18.8/1000). Only five infants (6%) were >1500 g. The majority of infections were caused by Candida albicans (59; 69%) and Candida parapsilosis (17; 20%); 33% of infants had received antifungal prophylaxis. Known risk factors (use of central venous catheter, parenteral nutrition, previous antibiotic use) were common among cases. The attributable case fatality rate was 21% (18/84). Extreme low birthweight infants remain at highest risk of invasive fungal infection and prophylaxis should be particularly considered for this group. The number needing to receive prophylaxis to prevent one case varies significantly among units, hence unit-specific decisions are required. Further research is still needed into the optimal empiric and therapeutic strategies.

Neonatal liver abscesses associated with candidemia: three cases and review of literature

BACKGROUND

Our aim was to identify risk factors for the development of neonatal Candida liver abscess and to find useful information to better manage this potentially fatal complication.

METHODS

A computerized search was conducted using PubMed. Overall, three articles describing the history of seven infants were finally considered. The characteristics of these seven cases were analyzed together with those of three new cases that we treated in the recent past.

RESULTS

All the neonates were premature. Previous antibiotic use was reported in all the cases, umbilical venous catheterization in 9/10 and total parenteral nutrition in 8/10. Candida albicans was isolated in 9/10. All the patients presented with aspecific signs of sepsis. Liver abscesses were described as "microabscesses" or "miliary abscesses" in three cases, as solitary lesion in two cases. In one case two lesions and in one four lesions were reported. Three infants died.

CONCLUSIONS

Liver ultrasonography should be performed in all the neonates with signs of sepsis, especially in the presence of candidemia and/or hepatomegaly and/or significant change in liver enzymes. Umbilical venous catheter should be removed, and peripheral IV access should be used until there is documented clearance from the blood with three or more negative blood cultures.

Old and new: appropriate dosing for neonatal antifungal drugs in the nursery

Candida infections are a source of significant mortality and morbidity in the neonatal intensive care unit. Treatment strategies continue to change as additional antifungals become available and studies in neonates are performed. Amphotericin B deoxycholate has been favored for many years, but fluconazole has the most data supporting its use in neonatal Candida infections and is often employed for prophylaxis as well as treatment. Voriconazole and posaconazole have limited utility in the nursery and are rarely used. The echinocandins are increasingly administered for invasive Candida infections, although higher doses are required in neonates than in older children and adults.

Candida parapsilosis is a significant neonatal pathogen: a systematic review and meta-analysis

BACKGROUND

Candida is the third most common cause of late-onset neonatal sepsis in infants born at <1500 g. Candida parapsilosis infections are increasingly reported in preterm neonates in association with indwelling catheters.

METHODS

We systematically reviewed neonatal literature and synthesized data pertaining to percentage of C. parapsilosis infections and mortality by meta-analyses. We also reviewed risk factors, virulence determinants, antimicrobial susceptibility patterns and outlined clinical management strategies.

RESULTS

C. parapsilosis infections comprised 33.47% (95% confidence interval [CI]: 30.02, 37.31) of all neonatal Candida infections. C. parapsilosis rates were similar in studies performed before the year 2000, 33.53% (95% CI: 30.06, 37.40) (28 studies), to those after 2000, 27.00% (95% CI: 8.25, 88.37) (8 studies). The mortality due to neonatal C. parapsilosis infections was 10.02% (95% CI: 7.66, 13.12). Geographical variations in C. parapsilosis infections included a low incidence in Europe and higher incidence in North America and Australia. Biofilm formation was a significant virulence determinant and predominant risk factors for C. parapsilosis infections were prematurity, prior colonization and catheterization. Amphotericin B remains the antifungal drug of choice and combination therapy with caspofungin or other echinocandins may be considered in resistant cases.

CONCLUSION

C. parapsilosis is a significant neonatal pathogen, comprises a third of all Candida infections and is associated with 10% mortality. Availability of tools for genetic manipulation of this organism will identify virulence determinants and organism characteristics that may explain predilection for preterm neonates. Strategies to prevent horizontal transmission in the neonatal unit are paramount in decreasing infection rates.

Newer antifungal agents

PURPOSE OF REVIEW

In recent years there has been an evolution of a better understanding of the pharmacology and clinical indications of existing antifungal agents and also the development of new broad-spectrum triazoles and a newer class of antifungal agents, the echinocandins. The availability of these agents has broadened the therapeutic options of invasive fungal disease among children and consequently antifungal therapy has become increasingly complex.

RECENT FINDINGS

Adoption of adult guidelines' recommendations has been used to guide pediatric treatment as specific pediatric data were often lacking. This approach has not always selected the most appropriate therapy for newborns or young infants, as the under-dosage of voriconazole based on adult data revealed. Therefore, a detailed understanding of the available antifungal agents in children is crucial for the successful treatment of these serious infections.

SUMMARY

In this review we summarize the main findings regarding antifungal treatment among children that have been recently published, focusing on the pharmacology and pediatric use of newer antifungal agents.