Practice Guidelines for the Diagnosis and Management of Aspergillosis: 2016 Update by the Infectious Diseases Society of America

Central Nervous System Aspergillosis: An Unexpected Complication following Neurosurgery

Post-surgical aspergillosis is an uncommon complication that carries a high mortality rate in affected patients. The diagnosis is challenging given the lack of highly sensitive methods to isolate Aspergillus from surgical sites. Here, we present a case of post-surgical aspergillosis that occurred after the resection of acoustic neuroma in an immunocompetent patient. Imaging revealed leptomeningeal enhancement and a cerebellar extra-axial fluid collection adjacent to the right retrosigmoid craniotomy. The patient was taken to the operating room for debridement, where purulent fluid was obtained from subdural space. The diagnosis was achieved by histopathology and polymerase chain reaction (PCR) in brain tissue. Appropriate investigations failed to detect contamination in the operating room. The patient was successfully treated with 3 months of voriconazole. We highlight the importance of recognizing this uncommon complication and advocate for the use of molecular techniques to improve the diagnostic yield in central nervous system aspergillosis.

Mechanistic Basis of pH-Dependent 5-Flucytosine Resistance in Aspergillus fumigatus

The antifungal drug 5-flucytosine (5FC), a derivative of the nucleobase cytosine, is licensed for the treatment of fungal diseases; however, it is rarely used as a monotherapeutic to treat Aspergillus infection. Despite being potent against other fungal pathogens, 5FC has limited activity against Aspergillus fumigatus when standard in vitro assays are used to determine susceptibility. However, in modified in vitro assays where the pH is set to pH 5, the activity of 5FC increases significantly. Here we provide evidence that fcyB, a gene that encodes a purine-cytosine permease orthologous to known 5FC importers, is downregulated at pH 7 and is the primary factor responsible for the low efficacy of 5FC at pH 7. We also uncover two transcriptional regulators that are responsible for the repression of fcyB and, consequently, mediators of 5FC resistance, the CCAAT binding complex (CBC) and the pH regulatory protein PacC. We propose that the activity of 5FC might be enhanced by the perturbation of factors that repress fcyB expression, such as PacC or other components of the pH-sensing machinery.

Evaluation of the Antifungal Activity of the Novel Oral Glucan Synthase Inhibitor SCY-078, Singly and in Combination, for the Treatment of Invasive Aspergillosis

Invasive aspergillosis remains a major cause of death among the immunocompromised population and those receiving long-term immunosuppressive therapy. In light of increased azole resistance, variable outcomes with existing echinocandin monotherapy and combination therapy, and persistent high mortality rates, new antifungal agents for the treatment of invasive aspergillosis are clearly needed. SCY-078 is the first-in-class triterpenoid antifungal, a novel class of glucan synthase inhibitors with broad in vitro and in vivo activity against a broad spectrum of Candida and Aspergillus species. In vitro testing of clinical strains of Aspergillus fumigatus and non-fumigatus Aspergillus strains showed that SCY-078 had potent fungistatic activity (minimum effective concentration for 90% of strains tested = 0.125 μg/ml) compared with the activities of amphotericin B (MIC₉₀ = 8 μg/ml) and voriconazole (MIC₉₀ = 2 μg/ml). Testing of SCY-078 in combination with isavuconazole or voriconazole demonstrated synergistic activity against the majority of the azole-susceptible strains tested, and SCY-078 in combination with amphotericin B was synergistic against the azole-susceptible strains, as well as one known resistant cyp51A mutant. SCY-078 may be an important additional antifungal for first-line or salvage monotherapy or combination treatment of invasive aspergillosis.

Therapeutic drug monitoring and safety of voriconazole therapy in patients with Child-Pugh class B and C cirrhosis: A multicenter study

OBJECTIVES

The purpose of this study was to investigate the pharmacokinetic profile and safety of voriconazole treatment in patients with Child-Pugh class B and C cirrhosis.

METHODS

Liver cirrhosis patients who had received the recommended voriconazole maintenance dose (group A) or halved maintenance dose (group B), orally or intravenously, were included. Voriconazole-related adverse events (AEs) were defined according to the Common Terminology Criteria for Adverse Events.

RESULTS

A total of 110 trough plasma concentrations of voriconazole (C_min) were measured in 78 patients. There was a significant difference in voriconazole C_min between group A and group B (C_min, 6.95±3.42mg/l vs. 4.02±2.00mg/l; p<0.001). No significant difference in voriconazole C_min between Child-Pugh class B and C cirrhosis patients was observed in either of the two groups. The international normalized ratio and co-medication with a CYP2C19 inhibitor had a significant effect on voriconazole C_min in group B. The incidence of AEs in group A was 26.5% and in group B was 15.9%, and 87.5% of AEs developed within 7days after starting voriconazole treatment.

CONCLUSIONS

These results suggest that the recommended dose and halved maintenance dose may be inappropriate in patients with Child-Pugh class B and C cirrhosis due to the high C_min, and that voriconazole C_min should be monitored earlier to avoid AEs.

Lack of Impact by SCY-078, a First-in-Class Oral Fungicidal Glucan Synthase Inhibitor, on the Pharmacokinetics of Rosiglitazone, a Substrate for CYP450 2C8, Supports the Low Risk for Clinically Relevant Metabolic Drug-Drug Interactions

SCY‐078, the first in a new class of β 1,3‐glucan synthesis inhibitors, is being developed as an oral and intravenous antifungal treatment for Candida and Aspergillus species fungal infections. In vitro, studies indicated SCY‐078 is an inhibitor of cytochrome P450 (CYP) 2C8 with markedly lower effect over other CYP isozymes. To examine clinically relevant effects of the potential interaction with SCY‐078, this phase 1, open‐label, 2‐period crossover study evaluated the pharmacokinetic parameters of rosiglitazone, a sensitive substrate of CYP2C8 metabolism, in the absence and presence of SCY‐078 dosed to therapeutically relevant SCY‐078 concentration exposure after repeat dosing. Healthy adult subjects were randomized to 2 treatment sequences: a single oral 4‐mg rosiglitazone dose alone on day 1 or a 1250‐mg SCY‐078 loading dose on day 1 followed by a once‐daily 750‐mg SCY‐078 dose for an additional 7 days (reflecting the clinical regimen evaluated during phase 2 studies for infections by Candida species) and concurrent administration of a single oral 4‐mg rosiglitazone dose on day 3, before alternating following a ≥10‐day washout. The exposure to SCY‐078 observed in this study was in line with the intended exposure for treatment of invasive fungal infections. The 90% confidence intervals for rosiglitazone exposure geometric mean ratios were within the prespecified no effect interval of 0.70‐1.43. Additionally, maximum concentration values for rosiglitazone and its metabolite, N‑desmethylrosiglitazone, were not significantly affected by co‐administration with SCY‐078. Overall, rosiglitazone exposure was not impacted to a clinically meaningful extent with co‐administration of therapeutically relevant SCY‐078 concentration exposure after repeat dosing. The results are indicative of low risk for interaction of SCY‐078 with drugs metabolized via the CYP family of enzymes.

Molecular Evolution of Antifungal Drug Resistance

The fungal pathogens Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus have transitioned from a rare curiosity to a leading cause of human mortality. The management of infections caused by these organisms is intimately dependent on the efficacy of antifungal agents; however, fungi that are resistant to these treatments are regularly isolated in the clinic, impeding our ability to control infections. Given the significant impact fungal pathogens have on human health, it is imperative to understand the molecular mechanisms that govern antifungal drug resistance. This review describes our current knowledge of the mechanisms by which antifungal drug resistance evolves in experimental populations and clinical settings. We explore current antifungal treatment options and discuss promising strategies to impede the evolution of drug resistance. By tackling antifungal drug resistance as an evolutionary problem, there is potential to improve the utility of current treatments and accelerate the development of novel therapeutic strategies.

Micafungin versus posaconazole prophylaxis in acute leukemia or myelodysplastic syndrome: A randomized study

OBJECTIVES

To compare the effectiveness and tolerability of micafungin versus posaconazole during chemotherapy-induced neutropenia in acute leukemia (AL) and myelodysplastic syndrome (MDS).

METHODS

Patients with AL or MDS undergoing chemotherapy were randomized to open-label micafungin 100 mg intravenously daily or posaconazole suspension 400 mg orally twice daily until neutrophil recovery, up to 28 days. Patients were followed for 12 weeks. The primary endpoint was prophylaxis failure (premature discontinuation due to infection, intolerance, adverse event, or death). Time to failure and survival were calculated by Kaplan-Meier analysis.

RESULTS

From March 2011 to May 2016, 113 patients who received at least 2 doses of prophylaxis were analyzed (58 patients randomized to micafungin and 55 to posaconazole). Prophylaxis failure occurred in 34.5% and 52.7% of patients on micafungin and posaconazole, respectively (P = 0.0118). The median number of days on prophylaxis was 16 [interquartile range (IQR) 12-20] for micafungin and 13 [IQR 6-16] for posaconazole (P = 0.01). Micafungin failures were largely due to antifungal treatment; posaconazole failures were mostly due to gastrointestinal intolerance or adverse effects. IFI incidence and survival were similar between study arms.

CONCLUSIONS

Our data support micafungin as alternative antifungal prophylaxis in patients with AL and MDS.

mTOR Modulates CD8+ T Cell Differentiation in Mice with Invasive Pulmonary Aspergillosis

CD8⁺ T cells are a vital component of the adaptive immune system and important for eliminating intracellular pathogens. Notably, mTOR activity is associated with CD8⁺ T effector memory (Tem) cell differentiation in fungal infections. This study investigates the molecular mechanisms of CD8⁺ Tem cell proliferation and differentiation mediated by the mTOR pathway in immunosuppressed mice with invasive pulmonary aspergillosis (IPA). We first established the immunosuppressed IPA mouse model, then mice were subjected to rapamycin treatment daily or interleukin (IL)-12 treatment every other day. Lung tissues and blood samples were obtained seven days later. Aspergillus fumigatus was cultured from the lung tissue of mice inoculated with A. fumigatus spores. After IL-12 treatment, the expression of mTOR and its downstream signaling molecule S6 kinase, number of CD8⁺ Tem cells and interferon-γ expression were significantly increased, while they were significantly decreased after treatment with rapamycin. Additionally, IL-12 treatment induced T-bet but inhibited Eomesodermin expression, while the opposite was seen when the mTOR pathway was blocked by rapamycin. In conclusion, we found that the mTOR pathway induced CD8⁺ T cell proliferation and differentiation by regulating T-bet and Eomesodermin expression, which significantly influenced immune regulation during IPA and enhanced the immune response against fungal infection.

Acute exacerbation of idiopathic pulmonary fibrosis triggered by Aspergillus empyema

Acute exacerbation (AE) is a severe and life-threatening complication of idiopathic pulmonary fibrosis (IPF). In 2016, the definition and diagnostic criteria for AE-IPF were updated by an international working group. The new definition includes any acute, clinically significant respiratory deterioration (both idiopathic and triggered events) characterized by evidence of new widespread alveolar abnormality in patients with IPF. There are no currently proven beneficial management strategies for idiopathic and triggered AE-IPF. This is the first report describing AE-IPF triggered by Aspergillus empyema, which was improved by a combination of corticosteroid, systemic antifungal therapy, local antifungal therapy, and additional pharmacological therapies. Future research may reveal optimal strategies for both idiopathic and triggered AE-IPF.

The scab-like sign: A CT finding indicative of haemoptysis in patients with chronic pulmonary aspergillosis?

OBJECTIVES

The aim of this study was to assess the CT findings that characterise haemoptysis in patients with chronic pulmonary aspergillosis (CPA).

METHODS

We retrospectively identified 120 consecutive patients with CPA (84 men and 36 women, 17-89 years of age, mean age 68.4 years) who had undergone a total of 829 CT examinations between January 2007 and February 2017. In the 11 patients who underwent surgical resection, CT images were compared with the pathological results.

RESULTS

The scab-like sign was seen on 142 of the 829 CT scans, specifically, in 87 of the 90 CT scans for haemoptysis and in 55 of the 739 CT scans obtained during therapy evaluation. In 48 of those 55 patients, haemoptysis occurred within 55 days (mean 12.0 days) after the CT scan. In the 687 CT scans with no scab-like sign, there were only three instances of subsequent haemoptysis in the respective patients over the following 6 months. Patients with and without scab-like sign differed significantly in the frequency of haemoptysis occurring after a CT scan (p<0.0001). Pathologically, the scab-like sign corresponded to a fibrinopurulent mass or blood crust.

CONCLUSIONS

The scab-like sign should be considered as a CT finding indicative of haemoptysis.

KEY POINTS

• Haemoptysis is commonly found in patients with CPA. • A CT finding indicative of haemoptysis in CPA patients is described. • Scab-like sign may identify CPA patients at higher risk of haemoptysis.

The burden of Invasive Aspergillosis in patients with haematological malignancy: A meta-analysis and systematic review

INTRODUCTION

Successful treatment of haematological malignancies is frequently complicated by Invasive Aspergillosis (IA), a life-threatening fungal infection that occurs in at least 10% of haemato-oncological patients. Case fatality rates (CFR) may fluctuate over time, depending on host pathogen interactions as well as on treatment and quality of patient care. We conducted a systematic review and metaanalysis of current - i.e. 2008-revised EORTC-MSG criteria era - incidence and case fatality rates (CFR) of IA in patients with haematological malignancy.

METHODS

A systematic search according to PRISMA guidelines was performed to identify all literature reporting populations with a haematological malignancy and the incidence of IA, defined according to the EORTC/MSG 2008 criteria. Pooled cumulative incidences and CFR within 100 days were estimated using a random effects model for predefined patient populations and stratified by use of prophylaxis.

RESULTS

The systematic literature search yielded 1285 publications of which n = 49 met the inclusion criteria. Overall, 16.815 patients were involved of which 1056 (6.3%) developed IA. IA risk ranged from 4% (during remission-induction, with prophylaxis) to 11% (during remission-induction, without prophylaxis). Antifungal prophylaxis was associated with a lower rate of IA, especially in the pre-HSCT population. The pooled CFR within 100 days was 29% (95% CI: 20-38%).

DISCUSSION

This study confirms that IA is a relevant threat in the treatment of haematological cancer despite the universal use of antifungal prophylaxis. These outcomes inform scientists and other stakeholders about the current burden of IA and may be used to direct, implement and improve antifungal stewardship programs.

Morphological changes and induction of antifungal resistance in Aspergillus fumigatus due to different CO2 levels

Background and Purpose

Aspergillosis is one of the most common opportunistic fungal infections in immunocompromised and neutropenic patients. Aspergillus fumigatus (A. fumigatus) is the most common causative agent of this infection. Due to variable CO₂ concentrations that pathogens are exposed to during the infection process and to understand the role of CO₂, we examined the effects of various CO₂ concentrations as one of the environmental factors on morphological changes and induction of antifungal resistance in A. fumigatus.

Materials and Methods

A. fumigatus strains were cultured and incubated under 1%, 3%, 5%, and 12% CO₂ atmospheres, each time for one, two, and four weeks. The control culture was maintained for one week without CO₂ atmosphere. Morphological changes were investigated and antifungal susceptibility test was performed according to the recommendations of the Clinical and Laboratory Standards Institute (CLSI) M38-A2 document. The results of different CO₂ atmospheres were compared with that of the control sample.

Results

We found that 1%, 3%, 5%, and 12% CO₂ atmospheres were associated with morphological colony changes. Macroscopically, the colonies were shallow dark green, smooth, crisp to powdery with reduced growth; microscopic examination revealed the absence of conidiation. The induction of antifungal resistance in the susceptible strains to itraconazole, voriconazole, and amphotericin B increased after exposure to 12% CO₂ atmosphere and four weeks of incubation. The MIC values for itraconazole, voriconazole, and amphotericin B were 16 g/ml, 1 g/ml, and 16 g/ml, respectively. These values for the control group were 0.125 g/ml, 0.125 g/ml, and 2 g/ml, respectively.

Conclusion

Exposure to different CO₂ atmospheres induced morphological changes in A. fumigatus, it seems to increase the MIC values, as well. In parallel, resistance to both itraconazole and voriconazole was also observed.

Adherence to, and outcomes of, a galactomannan screening protocol in high-risk hematology patients

Background

A twice-weekly galactomannan (gm) screening protocol was implemented in high-risk hematology inpatients. Study objectives were to determine adherence to the protocol, use of selected resources, and patient outcomes.

Methods

This retrospective cohort study compared outcomes of interest before and after implementation of gm screening. Adults undergoing matched related allogeneic hematopoietic stem-cell transplantation or induction chemotherapy for acute leukemia were eligible. Patients could be enrolled more than once and were evaluated as episodes. Adherence to the gm protocol was assessed in post-implementation episodes. Use of broad-spectrum antifungals (bsafs), consultations (infectious diseases, respirology), and diagnostic procedures (computed tomography imaging, bronchoalveolar lavage) were compared between phases, as were the patient outcomes of all-cause mortality and clinical success (alive and not taking a bsaf).

Results

Of 182 episodes consecutively screened, 70 per phase were enrolled. Clinical characteristics and duration of assessment were similar for the phases. Full or partial adherence to the protocol was observed in 61 post-implementation episodes (87%), with full adherence in 40 episodes (57%). More episodes in the pre-implementation phase than in the post-implementation phase involved receipt of bsafs, consultations, and diagnostics (27% vs. 7%, p = 0.02; 46% vs. 26%, p = 0.014; and 46% vs. 31%, p = 0.083 respectively). Although mortality was similar in the two phases, clinical success at the final assessment was observed in fewer pre-implementation than post-implementation episodes (79% vs. 98%, p < 0.001).

Conclusions

Implementation of a gm screening protocol was feasible and associated with significantly fewer episodes involving receipt of bsafs and consultations, and with significantly more episodes showing clinical success.

Aspergillus flavus native valve endocarditis following combined liver and renal transplantation: Case report and review of the literature

Aspergillus endocarditis is a rare infection that occurs most commonly in patients with prior cardiac surgery but cases in post-transplant recipients without prior cardiac surgery have been reported. Diagnosis is often delayed and requires high index of suspicion. We here report a case of Aspergillus endocarditis in solid organ transplant recipient.

Comparative systems analysis of the secretome of the opportunistic pathogen Aspergillus fumigatus and other Aspergillus species

Aspergillus fumigatus and multiple other Aspergillus species cause a wide range of lung infections, collectively termed aspergillosis. Aspergilli are ubiquitous in environment with healthy immune systems routinely eliminating inhaled conidia, however, Aspergilli can become an opportunistic pathogen in immune-compromised patients. The aspergillosis mortality rate and emergence of drug-resistance reveals an urgent need to identify novel targets. Secreted and cell membrane proteins play a critical role in fungal-host interactions and pathogenesis. Using a computational pipeline integrating data from high-throughput experiments and bioinformatic predictions, we have identified secreted and cell membrane proteins in ten Aspergillus species known to cause aspergillosis. Small secreted and effector-like proteins similar to agents of fungal-plant pathogenesis were also identified within each secretome. A comparison with humans revealed that at least 70% of Aspergillus secretomes have no sequence similarity with the human proteome. An analysis of antigenic qualities of Aspergillus proteins revealed that the secretome is significantly more antigenic than cell membrane proteins or the complete proteome. Finally, overlaying an expression dataset, four A. fumigatus proteins upregulated during infection and with available structures, were found to be structurally similar to known drug target proteins in other organisms, and were able to dock in silico with the respective drug.

Impact of CYP2C19 Genotype and Liver Function on Voriconazole Pharmacokinetics in Renal Transplant Recipients

BACKGROUND

Invasive fungal infection (IFI) is one of the leading causes of early death after renal transplantation. Voriconazole (VRC) is the first-line drug of IFI. Because of the large inter- and intraindividual variability in VRC plasma concentrations and the narrow therapeutic window for treating patients with IFIs, it is crucial to study the factors which could influence pharmacokinetic variability. We performed a population pharmacokinetics (PPK) study of VRC for personalized medicine.

METHODS

A total of 125 trough concentrations (Cmin) from 56 patients were evaluated, retrospectively. Nonlinear mixed effect model was used to describe a PPK model that was internally validated by bootstrap method. Potential covariates included demographic characteristics, physiological and pathological data, concomitant medications, and CYP2C19 genotype.

RESULTS

A 1-compartment model with first-order absorption and elimination was fit to characterize the VRC pharmacokinetics in renal transplant recipients (RTRs). Aspartate aminotransferase (AST) had a significant influence on clearance (CL) while CYP2C19 genotype had a major impact on the volume of distribution (V). The parameters of CL and V were 4.76 L/h and 22.47 L, respectively. The final model was V (L) = 22.47 × [1 + 2.21 × (EM = 1)] × [1 + 4.67 × (IM = 1)] × [1 + 3.30 × (PM = 1)] × exp (0.96); CL (L/h) = 4.76 × (AST/33)^(-0.23) × exp (0.14). VRC Cmin in intermediate metabolizers was significantly higher than in extensive metabolizers.

CONCLUSIONS

Liver function and CYP2C19 polymorphism are major determinants of VRC pharmacokinetic variability in RTRs. Genotypes and clinical biomarkers can determine the initial scheme. Subsequently, therapeutic drug monitoring can optimize clinical efficacy and minimize toxicity. Hence, this is a feasible way to facilitate personalized medicine in RTRs. In addition, it is the first report about PPK of VRC in RTRs.

Twelve-month clinical outcomes of 206 patients with chronic pulmonary aspergillosis

There is a paucity of evidence surrounding the optimal antifungal therapy for use in chronic pulmonary aspergillosis (CPA) and the duration of therapy remains unclear. We retrospectively evaluated treatment outcomes, including change in quality of life scores (St George’s Respiratory Questionnaire (QoL)), weight and Aspergillus IgG at 6 and 12 months following initiation of therapy in a cohort of 206 CPA patients referred to the UK National Aspergillosis Centre (NAC), Manchester between April 2013 and March 2015. One hundred and forty-two patients (69%) were azole naïve at presentation and 105 (74%) (Group A) were commenced on itraconazole, 27 (19%) on voriconazole, and 10 (7%) were not treated medically. The remainder (64 patients, 31%) had previously trialled, or remained on, azole therapy at inclusion (Group B) of whom 46 (72%) received itraconazole, 16 (25%) voriconazole, and 2 (3%) posaconazole. Initial therapy was continued for 12 months in 78 patients (48%) of those treated; the azole was changed in 62 (32%) patients and discontinued in 56 (29%) patients for adverse reactions (32, 57%), azole resistance (11, 20%), clinical failure (8, 14%) or clinical stability (5, 9%). Azole discontinuation rates were higher in Group B than in Group A (42% vs. 22%, p = 0.003). For all patients who survived, weight increased (median of 62.2Kg at baseline, to 64.8 at 12 months), mean Aspergillus IgG declined from 260 (baseline) to 154 (12 months) and QoL improved from 62.2/100 (baseline) to 57.2/100 (12 months). At 12 months, there was no difference in median survival between Groups A and B (95% vs. 91%, p = 0.173). The rate of emergence of resistance during therapy was 13% for itraconazole compared to 5% for voriconazole. Bronchial artery embolization was done in 9 (4.4%) patients and lobectomy in 7 (3.2%). The optimal duration of azole therapy in CPA is undetermined due to the absence of evidenced based endpoints allowing clinical trials to be undertaken. However we have demonstrated itraconazole and voriconazole are modestly effective for CPA, especially if given for 12 months, but fewer than 50% of patients manage this duration. This suggests extended therapy may be required for demonstrable clinical improvement.

Neutrophil extracellular traps in fungal infection

Fungal infections are a continuously increasing problem in modern health care. Understanding the complex biology of the emerging pathogens and unraveling the mechanisms of host defense may form the basis for the development of more efficient diagnostic and therapeutic tools. Neutrophils play a pivotal role in the defense against fungal pathogens. These phagocytic hunters migrate towards invading fungal microorganisms and eradicate them by phagocytosis, oxidative burst and release of neutrophil extracellular traps (NETs). In the last decade, the process of NET formation has received unparalleled attention, with numerous studies revealing the relevance of this neutrophil function for control of various mycoses. Here, we describe NET formation and summarize its role as part of the innate immune defense against fungal pathogens. We highlight factors influencing the formation of these structures and molecular mechanisms employed by fungi to impair the formation of NETs or subvert their antifungal effects.

Utility of posaconazole therapeutic drug monitoring and assessment of plasma concentration threshold for effective prophylaxis of invasive fungal infections: a meta-analysis with trial sequential analysis

Background

Posaconazole therapeutic drug monitoring (TDM) is increasingly used in clinical practice. However, the utility of posaconazole TDM and the target of posaconazole plasma concentration for clinical successful prophylaxis remain uncertain and controversial. The aim of this study was to evaluate posaconazole exposure-response relationship and determine an optimum posaconazole concentration for prophylaxis against invasive fungal infections (IFIs).

Methods

Bibliographic databases were searched (from inception to September 2017) to select studies including the clinical outcomes below and above concentration cut-off value of 0.5 mg/L and 0.7 mg/L. The reliability of the results were evaluated with trial sequential analysis (TSA).

Results

Twenty-eight studies with 1930 patients included were analyzed. The results of our pooled analysis demonstrated that patients with posaconazole plasma concentrations over 0.5 mg/L were twice more likely to achieve successful responses compared with those with lower concentrations (odds ratio, OR = 1.98, 95% confidence interval, CI 1.09–3.58, P = 0.02) while the threshold, 0.7 mg/L showed no significant difference (OR = 1.84, 95% CI 0.94–3.63, P = 0.08). The TSA results showed that there was sufficient information to support these findings.

Conclusions

An optimal posaconazole concentration target of 0.5 mg/L is suggested to ensure the clinical prophylactic efficacy and may help reduce the dosage and dose-dependent toxicity comparing with the target of 0.7 mg/L.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3055-3) contains supplementary material, which is available to authorized users.

In-host microevolution of Aspergillus fumigatus: A phenotypic and genotypic analysis

In order to survive, Aspergillus fumigatus must adapt to specific niche environments. Adaptation to the human host includes modifications facilitating persistent colonisation and the development of azole resistance. The aim of this study is to advance understanding of the genetic and physiological adaptation of A. fumigatus in patients during infection and treatment. Thirteen A. fumigatus strains were isolated from a single chronic granulomatous disease patient suffering from persistent and recurrent invasive aspergillosis over a period of 2 years. All strains had identical microsatellite genotypes and were considered isogenic. Whole genome comparisons identified 248 non-synonymous single nucleotide polymorphisms. These non-synonymous mutations have potential to play a role in in-host adaptation. The first 2 strains isolated were azole susceptible, whereas later isolates were itraconazole, voriconazole and/or posaconazole resistant. Growth assays in the presence and absence of various antifungal stressors highlighted minor changes in growth rate and stress resistance, with exception of one isolate showing a significant growth defect. Poor conidiation was observed in later isolates. In certain drug resistant isolates conidiation was restored in the presence of itraconazole. Differences in virulence were observed as demonstrated in a Galleria mellonella infection model. We conclude that the microevolution of A. fumigatus in this patient has driven the emergence of both Cyp51A-independent and Cyp51A-dependent, azole resistance mechanisms, and additional phenotypes that are likely to have promoted fungal persistence.

Posaconazole MIC Distributions for Aspergillus fumigatus Species Complex by Four Methods: Impact of cyp51A Mutations on Estimation of Epidemiological Cutoff Values

Estimating epidemiological cutoff endpoints (ECVs/ECOFFS) may be hindered by the overlap of MICs for mutant and nonmutant strains (strains harboring or not harboring mutations, respectively). Posaconazole MIC distributions for the Aspergillus fumigatus species complex were collected from 26 laboratories (in Australia, Canada, Europe, India, South and North America, and Taiwan) and published studies. Distributions that fulfilled CLSI criteria were pooled and ECVs were estimated. The sensitivity of three ECV analytical techniques (the ECOFFinder, normalized resistance interpretation [NRI], derivatization methods) to the inclusion of MICs for mutants was examined for three susceptibility testing methods (the CLSI, EUCAST, and Etest methods). The totals of posaconazole MICs for nonmutant isolates (isolates with no known cyp51A mutations) and mutant A. fumigatus isolates were as follows: by the CLSI method, 2,223 and 274, respectively; by the EUCAST method, 556 and 52, respectively; and by Etest, 1,365 and 29, respectively. MICs for 381 isolates with unknown mutational status were also evaluated with the Sensititre YeastOne system (SYO). We observed an overlap in posaconazole MICs among nonmutants and cyp51A mutants. At the commonly chosen percentage of the modeled wild-type population (97.5%), almost all ECVs remained the same when the MICs for nonmutant and mutant distributions were merged: ECOFFinder ECVs, 0.5 μg/ml for the CLSI method and 0.25 μg/ml for the EUCAST method and Etest; NRI ECVs, 0.5 μg/ml for all three methods. However, the ECOFFinder ECV for 95% of the nonmutant population by the CLSI method was 0.25 μg/ml. The tentative ECOFFinder ECV with SYO was 0.06 μg/ml (data from 3/8 laboratories). Derivatization ECVs with or without mutant inclusion were either 0.25 μg/ml (CLSI, EUCAST, Etest) or 0.06 μg/ml (SYO). It appears that ECV analytical techniques may not be vulnerable to overlap between presumptive wild-type isolates and cyp51A mutants when up to 11.6% of the estimated wild-type population includes mutants.

Surveillance for azoles resistance in Aspergillus spp. highlights a high number of amphotericin B-resistant isolates

Aspergillus spp. are the most common invasive mould infection and are responsible for high mortality. Aspergillus fumigatus is currently of interest because resistance to azole antifungals has emerged. The Campinas University Hospital (HC-UNICAMP) receives high-risk patients susceptible to opportunistic infections but there have been no reports of resistant A. fumigatus. This study aimed to assess the susceptibility profile of Aspergillus isolates, specifically looking for azole resistance. ITS and β-tubulin DNA sequencing was performed on 228 sequential clinical isolates. Broth microdilution susceptibility testing was performed for all isolates. A. fumigatus represented 74% of the isolates followed by Aspergillus flavus (12%). Nine A. fumigatus isolates from 9 different patients showed high MIC values to at least 1 azole, but cyp51A polymorphisms were detected in only 6 isolates and none correlated with known resistance mutations. The most troubling observation was that the minimum inhibitory concentration for amphotericin B was elevated (≥2 mg L^-1 ) in 87% of patients with A. flavus isolates and 43% with Aspergillus fumigatus isolates. Given that amphotericin B is used to treat azole-resistant infections, these data highlight the need for continuous surveillance in Aspergillus for all antifungal resistance to implement correct treatment strategies for the management of these pathogens.

Near-fatal mucormycosis post-double lung transplant presenting as uncontrolled upper gastrointestinal haemorrhage

Invasive fungal infections in immunosuppressed transplant patients are associated with significant morbidity and mortality. We present a case of splenic mucormycosis post-double lung transplant, presenting as uncontrolled near-fatal upper gastrointestinal haemorrhage, to remind clinicians of the need to consider pre-transplant invasive fungal infection risk factors if an unexpected fungal infection arises in the post-transplant period. This case also highlights the valuable contribution of molecular technology for fungal identification but also the need for clinical correlation.

[Pneumonia in immunocompromised patients]

Pneumonia occurs frequently in immunocompromised patients and often shows a complicated course of disease when compared to immunocompetent persons. The type of pathogen involved is directly associated with the type of immunosuppression and includes a wide variety of pathogens. Congenital and primary immunodeficiencies often appear during childhood. Acquired immunodeficiencies are most commonly caused by immunosuppressive medication. The concept of immunosuppression can be extended to patients with COPD or elderly patients because the variety of pathogens and specific features regarding frequency and course of the disease are similar to immunosuppressed patients. Computed tomography can provide an indication of the pathogen and is superior to the chest x‑ray in this respect. Blood cultures, antigen and PCR tests are non-invasive diagnostic tools for pathogen diagnostics. Invasive tests include fiberoptic bronchoscopy and complete the diagnostic methods of identifying the causative pathogen.

Role of bi-weekly serum galactomannan screening for the diagnosis of invasive aspergillosis in haematological cancer patients

Invasive aspergillosis (IA) is a life-threatening infection affecting haematological cancer patients with chemotherapy-induced neutropenia. The diagnosis of IA often relies on the detection of galactomannan (GM) in serum or bronchoalveolar lavage fluid (BAL). Bi-weekly serum GM screening has been proposed for a pre-emptive therapeutic approach of IA in patients not receiving mold-active prophylaxis. We have analysed all IA cases among patients with haematological malignancies and prolonged chemotherapy-induced neutropenia (>14 days) in our institution over a 10-year period (2007-2017). Serum GM was measured twice weekly and mold-active prophylaxis was not routinely administered. Thirty IA cases were observed and a positive serum GM was the first indicator of IA in 10 (33%) of them, which represents a need of approximately 500 GM tests for the detection of a single IA case. In the other 20 (67%) cases, suggestive chest CT lesion was the first sign of IA and bronchoscopy was required in 15 (50%) cases with negative serum GM for establishing the diagnosis of probable/proven IA. A positive serum GM was associated with a worse prognosis (57% 12-week survival vs 100% among serum GM-negative patients, P = .006), irrespective of the timing of GM positivity compared to CT. We concluded that bi-weekly serum GM screening demonstrated limited benefit in this population.

Aspergillus precipitating antibody in patients with Mycobacterium avium complex lung disease: A cross-sectional study

RATIONALE

Little is known about the role of Aspergillus precipitating antibody (APAb) in patients with Mycobacterium avium complex lung disease (MAC-LD).

OBJECTIVES

We investigated the clinical characteristics of patients with MAC-LD positive for APAb.

METHODS

We conducted a cross-sectional study targeting patients with MAC-LD. APAb was checked in all participants. Clinical variables included laboratory data, pulmonary function, high-resolution computed tomography findings, and health-related quality of life.

RESULTS

We analyzed 109 consecutive patients. Their median age was 68 years, and the median duration of MAC-LD was 4.8 years. Twenty (18.3%) patients tested positive for APAb. APAb-positive patients had significantly longer duration of MAC-LD (9.4 vs. 4.0 years, P = 0.017), more severe bronchiectasis evaluated by modified Reiff score (6.5 vs. 4, P = 0.0049), and lower forced expiratory volume in 1 s (%FEV₁) (75.1% vs. 86.2%, P = 0.013) than APAb-negative patients. Analysis of covariance adjusted for background factors and underlying pulmonary disease revealed that %FEV₁ was also significantly lower in patients with APAb (P = 0.045). Ten patients were newly diagnosed with chronic pulmonary aspergillosis (N = 5) or allergic bronchopulmonary aspergillosis (N = 5).

CONCLUSIONS

APAb is associated with lower pulmonary function, and observed especially in patients with longer duration of MAC-LD and severe bronchiectasis, even in the absence of cavitary lesions.

Posaconazole achieves prompt recovery of voriconazole-induced liver injury in a case of invasive aspergillosis

Azole antifungals have frequently been linked to the presence of hepatotoxicity, but there is scarce information on cross-toxicity between these drugs or on the possibility of using some of them when this type of toxicity occurs. We report the case of a 64-year-old man with invasive aspergillosis (IA) leading to spondylodiscitis with neurological involvement. Early management included intravenous (iv) voriconazole, which had to be interrupted after 1 week due to liver damage. Therapeutic drug monitoring (TDM) of voriconazole showed that the plasma concentration was within the therapeutic range. However, it was replaced by a combination therapy of oral posaconazole plus iv caspofungin. Posaconazole allowed normalization of liver enzymes. After finishing posaconazole monotherapy on an outpatient basis, the patient made a full recovery. This case report provides further evidence that oral posaconazole is safe and effective as rescue therapy after the appearance of voriconazole-induced liver toxicity.

Issues in the management of invasive pulmonary aspergillosis in non-neutropenic patients in the intensive care unit: A role for isavuconazole

Background

Almost half of all cases of invasive aspergillosis (IA) occur in the intensive care unit (ICU), with mortality rates of 70–80% for probable or proven cases. IA has become a major concern among non-neutropenic patients in the ICU with chronic obstructive pulmonary disease (COPD) but although prompt, appropriate antifungal therapy is crucial, diagnosis in this situation is challenging. Criteria for a probable diagnosis in critically ill patients have been proposed to help to expedite therapy.

Methods

A case of probable invasive pulmonary aspergillosis (IPA) in a non-neutropenic patient admitted to the ICU was used to illustrate potential issues in the diagnostic work-up and management of patients in this setting.

Results

A non-neutropenic 69-year-old man with COPD receiving clomipramine was diagnosed in the ICU with probable invasive aspergillosis based on the presence of severe chronic obstructive pulmonary disease, suspected X-linked granulomatous disease, nodular infiltrates and galactogamman positivity on bronchoalveolar lavage (BAL) fluid. Voriconazole was unsuitable due to the patient's prolonged QT interval and risk of a drug–drug interaction with clomipramine. Isavuconazole was initiated and the patient's condition improved. The three-month course of isavuconazole treatment was well-tolerated and resulted in compete recovery of the patient.

Conclusions

Voriconazole is a standard first-line treatment for IA but intravenous therapy is associated with toxicity and the potential for drug–drug interactions. Isavuconazole is another first-line therapy which was effective and safe in the management of this critically ill non-neutropenic patient with baseline QT prolongation and potential drug–drug interactions with voriconazole.

[Invasive pulmonary aspergillosis]

INTRODUCTION

Invasive pulmonary aspergillosis (IPA) is an important cause of morbidity and mortality in a wide range of patients. Early recognition and diagnosis have become a major focus in improving the management and outcomes of this life-threatening disease.

BACKGROUND

IPA typically occurs during a period of severe and prolonged neutropenia. However, solid organ transplant recipients, patients under immunosuppressive therapy or hospitalized in intensive care units are also at risk. The diagnosis is suspected in the presence of a combination of clinical, biological and CT scan evidence. The microbiological diagnostic strategy should be adapted to the patient's profile. Conventional methods with culture and species identification remain the standard but early diagnosis has been improved by the use of biomarkers such as galactomannan antigen in serum or in bronchoalveolar lavage.

OUTLOOK

The epidemiology of IPA should change with the increased use of antifungal prophylactic regimens and the arrival of targeted therapies. Other microbiological tools, such as PCR and other biomarkers, are currently being assessed.

CONCLUSIONS

IPA must be considered in a wide range of patients. Its prognosis remains poor despite progress in the microbiological diagnosis and therapeutic management.

Hyperbaric Oxygen Reduces Aspergillus fumigatus Proliferation In Vitro and Influences In Vivo Disease Outcomes

Recent estimates suggest that more than 3 million people have chronic or invasive fungal infections, causing more than 600,000 deaths every year. Aspergillus fumigatus causes invasive pulmonary aspergillosis (IPA) in patients with compromised immune systems and is a primary contributor to increases in human fungal infections. Thus, the development of new clinical modalities as stand-alone or adjunctive therapy for improving IPA patient outcomes is critically needed. Here we tested the in vitro and in vivo impacts of hyperbaric oxygen (HBO) (100% oxygen, >1 atmosphere absolute [ATA]) on A. fumigatus proliferation and murine IPA outcomes. Our findings indicate that HBO reduces established fungal biofilm proliferation in vitro by over 50%. The effect of HBO under the treatment conditions was transient and fungistatic, with A. fumigatus metabolic activity rebounding within 6 h of HBO treatment being removed. In vivo, daily HBO provides a dose-dependent but modest improvement in murine IPA disease outcomes as measured by survival analysis. Intriguingly, no synergy was observed between subtherapeutic voriconazole or amphotericin B and HBO in vitro or in vivo with daily HBO dosing, though the loss of fungal superoxide dismutase genes enhanced HBO antifungal activity. Further studies are needed to optimize the HBO treatment regimen and better understand the effects of HBO on both the host and the pathogen during a pulmonary invasive fungal infection.

Investigation of Multiple Resistance Mechanisms in Voriconazole-Resistant Aspergillus flavus Clinical Isolates from a Chest Hospital Surveillance in Delhi, India

Invasive and allergic infections by Aspergillus flavus are more common in tropical and subtropical countries. The emergence of voriconazole (VRC) resistance in A. flavus impacts the management of aspergillosis, as azoles are used as the first-line and empirical therapy. We screened 120 molecularly confirmed A. flavus isolates obtained from respiratory and sinonasal specimens in a chest hospital in Delhi, India, for azole resistance using the CLSI broth microdilution (CLSI-BMD) method. Overall, 2.5% (n = 3/120) of A. flavus isolates had VRC MICs above epidemiological cutoff values (>1 μg/ml). The whole-genome sequence analysis of three non-wild-type (WT) A. flavus isolates with high VRC MICs showed polymorphisms in azole target genes (cyp51A, cyp51B, and cyp51C). Further, four novel substitutions (S196F, A324P, N423D, and V465M) encoded in the cyp51C gene were found in a single non-WT isolate which also exhibited overexpression of cyp51 (cyp51A, -B, and -C) genes and transporter genes, namely, MDR1, MDR2, atrF, and mfs1 The homology model of the non-WT isolate suggests that substitutions S196F and N423D exhibited major structural and functional effects on cyp51C drug binding. The substrate (drug) may not be able to bind to binding pocket due to changes in the pocket size or closing down or narrowing of cavities in drug entry channels. Notably, the remaining two VRC-resistant A. flavus isolates, including the one which had a pan-azole resistance phenotype (itraconazole and posaconazole), did not show upregulation of any of the analyzed target genes. These results suggest that multiple target genes and mechanisms could simultaneously contribute to azole resistance in A. flavus.

Advances in the diagnosis and treatment of fungal infections of the CNS

Fungal infections of the CNS are challenging to treat and their optimal management requires knowledge of their epidemiology, host characteristics, diagnostic criteria, and therapeutic options. Aspergillus and Cryptococcus species predominate among fungal infections of the CNS. Most of these fungi are ubiquitous, but some have restricted geographical distribution. Fungal infections of the CNS usually originate from primary sites outside the CNS (eg, fungal pneumonia) or occur after inoculation (eg, invasive procedures). Most patients with these infections have immunodeficiencies, but immunocompetent individuals can also be infected through heavy exposure. The infecting fungi can be grouped into moulds, yeasts, and dimorphic fungi. Substantial progress has been made with new diagnostic approaches and the introduction of novel antifungal drugs, but fungal infections of the CNS are frequently lethal because of diagnostic delays, impaired drug penetration, resistance to antifungal treatments, and inadequate restoration of immune function. To improve outcomes, future research should advance diagnostic methods (eg, molecular detection and fungus identification), develop antifungal compounds with enhanced CNS-directed efficacy, and further investigate crucial host defence mechanisms.

ADJunctive Ulinastatin in Sepsis Treatment in China (ADJUST study): study protocol for a randomized controlled trial

Background

Sepsis is a major challenge in critical care and is associated with high mortality. Current management of sepsis and septic shock remains mainly supportive. Both basic and clinical research has shown that ulinastatin can improve the prognosis of sepsis. The aim of this trial is to evaluate the efficacy and safety profiles of ulinastatin compared with placebo.

Methods/design

In this multi-center, double-blind, randomized placebo-controlled trial we are recruiting a total of 348 subjects meeting “The Third International Consensus Definitions for Sepsis and Septic Shock” (Sepsis-3). Subjects will be randomized (1:1) to receive ulinastatin 400,000 IU three times a day for 10 days or matching placebo and usual care simultaneously. The primary outcome is 28-day all-cause mortality. Adverse events and serious adverse events will be monitored closely.

Discussion

ADJUST is a large, multi-center, double-blind, randomized, parallel-group, placebo-controlled trial of ulinastatin in mainland China and is well-designed on the basis of previous studies. The results of this trial may help to provide evidence-based recommendations for treatment of sepsis.

Trial registration

ClinicalTrials.gov, ID: NCT02647554. First registered on 27 December 2015, and last verified in December of 2016.

Protocol version: 2.1, verified on 19 July 2016.

Pharmacodynamics of Isavuconazole for Invasive Mold Disease: Role of Galactomannan for Real-Time Monitoring of Therapeutic Response

Background.

The ability to make early therapeutic decisions when treating invasive aspergillosis using changes in biomarkers as a surrogate for therapeutic response could significantly improve patient outcome.

Methods.

Cox proportional hazards model and logistic regression were used to correlate early changes in galactomannan index (GMI) to mortality and overall response, respectively, from patients with positive baseline GMI (≥0.5) and serial GMI during treatment from a phase 3 clinical trial for the treatment of invasive mold disease. Pharmacokinetic/pharmacodynamic (PK/PD) analysis in patients with isavuconazole plasma concentrations was conducted to establish the exposure necessary for GMI negativity at the end of therapy.

Results.

The study included 158 patients overall and 78 isavuconazole patients in the PK/PD modeling. By day 7, GMI increases of >0.25 units from baseline (3/130 survivors; 9/28 who died) significantly increased the risk of death compared to those with no increase or increases <0.25 (hazard ratio, 9.766; 95% confidence interval [CI], 4.356–21.9; P < .0001). For each unit decrease by day 7 from baseline, the odds of successful therapy doubled (odds ratio, 2.154; 95% CI, 1.173–3.955). An area under the concentration-versus-time curve over half-maximal effective concentration (AUC:EC₅₀) of 108.6 is estimated to result in a negative GMI at the end of isavuconazole therapy.

Conclusions.

Early trends in GMI are highly predictive of patient outcome. GMI increases by day 7 could be considered in context of clinical signs to trigger changes in treatment, once validated. Our data suggest that this improves survival by 10-fold and positive outcome by 3-fold. These data have important implications for individualized therapy for patients and clinical trials.

Clinical Trials Registration.

NCT00412893.

Favorable Outcome in Coccidioides Endophthalmitis-A Combined Medical and Surgical Treatment Approach

PURPOSE

To describe a case of Coccidioides endophthalmitis that resulted in a favorable visual outcome after a combined medical and surgical approach.

METHODS

A 33-year-old previously healthy woman was referred for evaluation of dyspnea and left-sided vision loss, which began 3 months before, after a trip to Nevada. She was found to have a pulmonary cavitary lesion and fluffy white material in the anterior chamber. An aqueous and vitreous paracentesis grew Coccidioides species. She was managed medically with a total of 7 weekly intravitreal injections of amphotericin B and intravenous liposomal amphotericin B followed by transition to oral posaconazole. Seven months after presentation, to ensure ocular sterilization and to clear the visual axis, she underwent temporary keratoprosthesis implantation, anterior segment reconstruction, removal of a cyclitic membrane and the crystalline lens, pars plana vitrectomy, placement of a pars plana Ahmed drainage device, and penetrating keratoplasty.

RESULTS

After surgical intervention and with maintenance posaconazole therapy, the patient had resolution of her dyspnea and improved uncorrected (aphakic) vision with a clear corneal graft, quiet anterior chamber, and normal optic nerve and retina.

CONCLUSIONS

A combined medical and surgical approach resulted in a favorable visual outcome and avoided the need for enucleation.

The North Wind and the Sun: Pediatric Antimicrobial Stewardship Program Combining Restrictive and Persuasive Approaches in Hematology-Oncology Ward and Hematopoietic Stem Cell Transplant Unit

BACKGROUND

The Japanese government's goal for the reduction of antimicrobial consumption is two-thirds of the 2013 rate by 2020. While the antimicrobial stewardship programs (ASPs) are essential in health care facilities, ASP data on pediatric hematology-oncology and hematopoietic stem cell transplant (HSCT) patients are limited. Our aim was to evaluate the impact of restrictive and persuasive ASP on immunocompromised children.

METHODS

The ASP for hematology-oncology and HSCT patients at Tokyo Metropolitan Children's Medical Center was assessed. Phase 1 was a postprescriptive review of carbapenem conducted between April 2010 and September 2011. Phase 2 consisted of the preauthorization of carbapenem, prospective audit with feedback, a weekly luncheon meeting among physicians, consensus on febrile neutropenia management, and implementation of viral molecular diagnostics between October 2011 and September 2015. Both phases were compared for day-of-therapy per 1,000 patient-days, cost of intravenous antimicrobial agents, average hospitalization duration, all-cause mortality, infection-related mortality at 30 days, and appropriateness of empirical treatment of bacteremia.

RESULTS

The ASP did not differ from phase 1 to phase 2 in terms of average hospitalization length, mortality rate, or appropriateness of empirical treatment for bacteremia. Day-of-therapies of cefepime, piperacillin/tazobactam, meropenem, vancomycin, liposomal amphotericin B, and fosfluconazole decreased by 20%, 45%, 57%, 38%, 85% and 44%, respectively (P < 0.05). The total cost of antibiotic and antifungal agents decreased by 27%, for a savings of $59,905 USD annually.

CONCLUSION

Restrictive and persuasive ASP in the hematology-oncology ward and the HSCT unit safely decreased the use of antibacterial and antifungal agents.