Update on the optimal use of voriconazole for invasive fungal infections

Phaeohyphomycosis caused by Corynespora cassiicola, a plant pathogen worldwide

Although rare, trans-kingdom infection features an interesting infection biology concept, in which highly versatile pathogenic attributes allow successful infections in evolutionarily highly divergent species. Corynespora cassiicola is a phytopathogenic fungus and occasionally causes human infections. Herein, we report a phaeohyphomycosis case caused by C. cassiicola. Given that sporadic reports may contribute to a lack of awareness of the transmission route, clinical manifestations, and diagnostic and clinical management, we systematically reviewed the cases reported thus far. Nine patients were identified and included in the pooled analysis, 88.9% (8/9) of whom were reported after 2010. All patients were from Asian, African, and Latin American countries, among whom 77.8% (7/9) were farmers or lived in areas with active agriculture. Exposed body parts were the major affected infection area, and clinical manifestations were mainly non-specific inflammatory reactions. Although biochemical and morphological examinations confirmed the presence of fungal infection, molecular analysis was used for the final diagnosis, with 77.8% (7/9) being identified by internal transcribed spacer sequencing. Whereas voriconazole, terbinafine, and AmB, either alone or in combination, resulted in successful infection resolution in most cases (5/9; 55.5%), those suffering from invasive facial infections and CARD9 deficiency showed poor outcomes. Our patient is the third case of invasive facial infection caused by C. cassiicola and was successfully treated with intravenous LAmB followed by oral voriconazole combined with topical antifungal irrigation. Molecular identification of fungus and prompt antifungal treatment is pivotal in the clinical success of patients suspected to have phaeohyphomycosis. Moreover, as evidenced by our data, itraconazole treatment is not recommended.

A Case of Invasive Pulmonary Aspergillosis vs. Pulmonary Aspergilloma in Immunocompromised Patient With Preexisting Lung Cavity

Subacute invasive aspergillosis (SAIA) occurs in immunocompromised patients and/or patients with preexisting pulmonary pathology. An aspergilloma is a fungus ball that occurs in preexisting lung cavities and can be relatively asymptomatic without tissue invasion. In contrast to an aspergilloma, SAIA invades local tissue and parenchyma, resulting in tissue necrosis. We present a case of a 68-year-old immunocompromised female with a past medical history of hypertension, hyperlipidemia, chronic obstructive pulmonary disease (COPD), stage IIIA adenocarcinoma, and a preexisting pulmonary cavity with chronic invasive aspergillosis vs. pulmonary aspergilloma treated with oral (PO) voriconazole. This case demonstrates that invasive aspergillosis should be considered in the differential diagnosis of any pulmonary lung lesion showing tissue invasion and expansion in an immunocompromised patient.

Voriconazole-Induced Cholestatic Hepatotoxicity in an Immune Competent Patient

Voriconazole is a frequently prescribed anti-fungal medication used in particular for invasive aspergillosis. Voriconazole-induced hepatotoxicity is a relatively rare but serious clinicopathologic entity. We report a patient presenting with impaired liver function test results pointing towards the cholestatic picture. The patient had initial blood tests to confirm cholestasis, followed by imaging modalities that did not show any obstruction along the common bile duct and/or pancreatic pathway. The patient’s voriconazole dose reduction was advised, resulting in lower levels of abnormal liver function tests.

Association of Voriconazole Trough Plasma Concentration with Efficacy and Incidence of Hepatotoxicity in Iranian Patients with Hematological Malignancies

There are conflicting data regarding the association between plasma concentration of voriconazole (VCZ) and both efficacy and safety. This study investigates the association of VCZ trough plasma level with clinical efficacy and hepatotoxicity in the Iranian population suffering hematological malignancies. This cross-sectional study was performed on adult Iranian patients (age ≥ 18 years) with hematological malignancies undergoing treatment with oral or intravenous VCZ for proven or probable invasive aspergillosis. Plasma concentrations of VCZ were measured at two time points on day 4 and 14 during the study period. A total of 60 VCZ trough concentrations of 30 patients were drawn on days 4 and 14 after the initiation of treatment. There was no definite correlation between the mean plasma concentration of VCZ and VCZ dosage (p = 0.134, r = 0.280). In multivariable model, only plasma concentration of VCZ on day 14 was associated with the incidence of hepatotoxicity (p = 0.013; OR = 1.42, 95% CI = 1.07-3.24). Plasma trough concentration neither on day 4 nor on day 14 was related to the treatment response. No significant association was observed between the mean plasma concentration of VCZ and 3-month patients’ survival (p = 0.696). To conclude, VCZ trough concentration may not be a predictor of treatment response or 3-month patients’ survival. However, the wide inter- and intra-patient variability of VCZ plasma concentration coupled with the observed association between VCZ trough level and the incidence of hepatotoxicity would pose the question regarding the potential benefit of VCZ concentration monitoring.

Characterization of Therapeutic Drug Monitoring Practices of Voriconazole and Posaconazole at a Pediatric Hospital

OBJECTIVES

To characterize the voriconazole and posaconazole serum trough ordering practices in patients receiving prophylactic and treatment antifungal therapy.

METHODS

A retrospective chart review over a 6-year period of pediatric patients who received voriconazole and/or posaconazole for >24 hours.

RESULTS

A total of 113 patients were included in this study and of these patients, 105 received voriconazole and 16 received posaconazole during the study period. Additionally, 167 trough levels were assessed in this study. Only 50% and 54% of levels were considered within goal recommendations for voriconazole and posaconazole, respectively. The median dose required to achieve goal trough concentration was dependent on drug, indication, and dosage form. Lastly, the most common adverse drug reactions (ADRs) were hepatoxicity, QTc prolongation, and CNS changes, which were in concordance with ADRs documented in the clinical trials for voriconazole and posaconazole. Approximately 20% of patients receiving either voriconazole or posaconazole died during the study period and the median trough in both groups was subtherapeutic.

CONCLUSIONS

Increased monitoring of trough concentrations may be warranted to prevent death or breakthrough invasive fungal infections. Further studies are warranted for assessing the relationship between trough concentrations and treatment outcomes as well as relationship between dosing and achieving goal trough concentrations.

A Guidance for Concomitant Drug Reconciliation Prior to Allogeneic Hematopoietic Cell Transplantation in Children and Young Adults

Pediatric diseases treated by allogeneic hematopoietic stem cell transplantation (alloHCT) are complex and associated with significant comorbidities and medication requirements that can complicate the transplant process. It is critical to reconcile pre-transplant concomitant medications (pcon-meds) in the weeks prior to alloHCT and to consider the potential for pcon-meds to cause harmful drug-drug interactions (DDIs) or overlapping toxicities with conditioning agents. In this perspective, we describe a systematic process to review pcon-meds and determine the drug modifications needed to avoid DDIs with conditioning regimens. We provide an extensive appendix with timelines for discontinuation or modification of common pcon-meds that patients are taking when presenting to the HCT medical team. The timelines are based on the pharmacokinetic (PK) properties of both the pcon-meds and the planned conditioning medications, as well as anticipated DDIs. They also account for the ages seen at pediatric transplant centers (0-30 years old). Common scenarios, such as when pcon-med discontinuation is not an option, are discussed. Since alloHCT patients are often dependent upon psychiatric medications with problematic DDIs, a table of alternative, non-interacting psychiatric medications is also presented. The appendix provides details regarding how to adjust pcon-meds prior to the start of chemotherapy for children and young adults undergoing alloHCT, however patient-specific circumstances always need to be taken into account. Careful attentiveness to pcon-meds at the time the decision is made to pursue transplant will result in more consistent HCT outcomes, with lower toxicity and increased efficacy of conditioning agents.

Hypertrophic pachymeningitis caused by Schizophyllum sp.: a novel case report

BACKGROUND

The pathogenic fungus Schizophyllum sp. can cause allergic fungal rhinosinusitis and allergic bronchopulmonary mycosis in humans. Sinus and lung infections due to Schizophyllum sp. have been reported globally; however, no case of hypertrophic pachymeningitis due to this pathogen has been reported yet. Herein, we describe for the first time, a case of hypertrophic pachymeningitis due to Schizophyllum sp.

CASE PRESENTATION

A 69-year-old woman visited the hospital with chief complaints of headache, right trigeminal neuralgia (third branch), ataxic gait, and deafness in the right ear. Magnetic resonance imaging revealed a tumor in the right sphenoidal sinus and thickening of the dura mater surrounding the right porus acusticus internus. Endoscopic sinus surgery and neuroendoscopic biopsy were performed to remove sinus lesions and intracranial lesions, respectively. Both pathological specimens showed findings indicative of filamentous fungi on Grocott's staining. DNA sequencing with the sinus specimen revealed Schizophyllum sp. as the causative pathogen, consistent with the diagnosis of fungal sinusitis and hypertrophic pachymeningitis. Intravenous liposomal amphotericin B was started, but owing to lack of improvement, the treatment was switched to intravenous voriconazole. We observed improvements in both radiological findings and symptoms. However, the symptoms exacerbated again when the trough level of voriconazole decreased. Upon increasing the voriconazole dose, a higher trough level was obtained and the symptoms improved.

CONCLUSION

Our study suggests that when symptoms of central nervous system infection due to Schizophyllum sp. do not improve with liposomal amphotericin B, voriconazole can be administered at high trough levels to improve the symptoms.

Ocular Inserts of Voriconazole-Loaded Proniosomal Gels: Formulation, Evaluation and Microbiological Studies

BACKGROUND

Voriconazole (VRC) is a triazole broad spectrum antifungal drug, used in the management of versatile fungal infections, particularly fungal keratitis. The obligatory use of niosomal delivery of VRC may reduce the frequency of dosing intervals resulting from its short biological half time and consequently improve patient compliance.

METHODS

VRC loaded proniosomes (VRC-PNs) were set by the coacervation technique and completely characterized. The developed formula was comprehensively assessed concerning in- vitro release behavior, kinetic investigation, and its conflict against refrigerated and room temperature conditions. A selected noisomal formula was incorporated into ocusert (VRC-PNs Ocu) formulated by 1% w/w hydroxypropyl methyl cellulose HPMC and 0.1% w/w carbopol 940. Eventually, in vitro antifungal activity against Candida albicans and Aspergillus nidulans was assessed by the cup diffusion method.

RESULTS

The optimized VRC-PNs (Pluronic F127: cholesterol weight ratio 1:1 w/w) exhibited the highest entrapment efficiency (87.4±2.55%) with a spherical shape, proper size in nano range and a suitable Zeta potential of 209.7±8.13 nm and -33.5±1.85 mV, respectively. Assurance of drug encapsulation in nanovesicles was accomplished by several means such as attenuated total reflection Fourier-transform infrared spectroscopy, differential scanning calorimetry in addition to powder X-ray diffraction investigations. It displayed a biphasic in vitro release pattern and after 6 months of storage at a refrigerated temperature, the optimized formula preserved its stability. VRC-PNs Ocu proved a very highly significant antifungal activity matched with the free drug or nanosuspension which was extra assured by comparing its mean inhibition zone with that of 5% natamycin market eye drops.

CONCLUSION

In conclusion, VRC-PNs Ocu could be considered as a promising stable sustained release topical ocular nanoparticulate system for the management of fungal infections.

Tryptophol Coating Reduces Catheter-Related Cerebral and Pulmonary Infections by Scedosporium apiospermum

Introduction

Central venous catheter (CVC) is a medical device that is used to administer medication for a long duration. Colonization by an emerging opportunistic pathogen Scedosporium apiospermum in the CVC lumen is frequently reported to cause severe complications in patients. Here, we describe the effect of fungal quorum-sensing molecule (QSM) known as tryptophol (TOH) to control S. apiospermum colonization in catheter tube lumens in both in vitro and in vivo models.

Methods

Antifungal susceptibility of TOH against S. apiospermum was compared with voriconazole, and the colony diameter was determined on days 2, 4, and 6. Experimental catheterization rat model was conducted with pre-coating of TOH and voriconazole or an uncoated control and an infection with S. apiospermum. Biofilm formation on the catheter luminal surface was assessed using the scanning electron microscopy, crystal violet, and 2,3-bis(2-methoxy-4-ni-tro-5-sulfophenyl)-5-(phenylamino)-carbonyl-2H-tetra-zolium hydroxide (XTT) reduction assays. Brain and lung samples of catheterized rats were histopathologically assessed. Serum samples from catheterized rats were injected into Galleria mellonella larvae. Survival of catheterized rats and G. mellonella was determined.

Results

TOH impeded the growth of S. apiospermum by reducing the colony diameter in a dose-dependent manner. TOH coating remarkably lessened S. apiospermum biofilm formation and fungal cell viability on the catheter luminal surface. Additionally, TOH coating lessens cerebral edema that is associated with abscess and invasive pulmonary damages due to S. apiospermum catheter-related infection. Furthermore, TOH coating also lessened the virulence of S. apiospermum in sera of experimental catheterized rats and extended the survival rate of larvae Galleria mellonella infection model.

Conclusion

An alternative modification of catheter by coating with TOH is effective in preventing S. apiospermum colonization in vivo. Our study gives a new strategy to control catheter contamination and prevents nosocomial diseases due to S. apiospermum infection.

In vitro antifungal activity of a novel topical triazole PC945 against emerging yeast Candida auris

Objectives

Management of Candida auris infection is difficult as this yeast exhibits resistance to different classes of antifungals, necessitating the development of new antifungals. The aim of this study was to investigate the susceptibility of C. auris to a novel antifungal triazole, PC945, optimized for topical delivery.

Methods

A collection of 50 clinical isolates was obtained from a tertiary care hospital in North India. Nine isolates from the UK, 10 from a CDC panel (USA) and 3 from the CBS-KNAW culture collection (Japanese and South Korean isolates) were also obtained. MICs (azole endpoint) of PC945 and other triazoles were determined in accordance with CLSI M27 (third edition). Quality control strains were included [Candida parapsilosis (ATCC 22019) and Candida krusei (ATCC 6258)].

Results

Seventy-four percent of isolates tested showed reduced susceptibility to fluconazole (≥64 mg/L). PC945 (geometric mean MIC = 0.058 mg/L) was 7.4-fold and 1.5-fold more potent than voriconazole and posaconazole, respectively (both P < 0.01). PC945 MIC values correlated with those of voriconazole or posaconazole, and only three isolates were found to be cross-resistant between PC945 and other azoles. ERG11 sequence analysis revealed several mutations, but no correlation could be established with the MIC of PC945. Tentative epidemiological cut-off values (ECOFFs) evaluated by CLSI’s ECOFF Finder (at 99%) with 24 h reading of MICs were 1, 4 and 1 mg/L for PC945, voriconazole and posaconazole, respectively. MIC values for quality control strains of all triazoles were in the normal ranges.

Conclusions

PC945 was found to be a more potent inhibitor than posaconazole, voriconazole and fluconazole of C. auris isolates collected globally, warranting further laboratory and clinical evaluations.

Voriconazole enhances UV-induced DNA damage by inhibiting catalase and promoting oxidative stress

Cutaneous squamous cell carcinoma (cSCC) is the second most common form of skin cancer and is associated with cumulative UV exposure. Studies have shown that prolonged voriconazole use promotes cSCC formation; however, the biological mechanisms responsible for the increased incidence remain unclear. Here, we show that voriconazole directly increases oxidative stress in human keratinocytes and promotes UV-induced DNA damage as determined by comet assay, 8-oxoguanine immunofluorescence and mass spectrometry. Voriconazole treatment of human keratinocytes potentiates UV-induced apoptosis and activation of the p38 MAP kinase and 53BP1 UV stress response pathways. The p38 MAP kinase activation promoted by voriconazole exposure can be mitigated by pretreating keratinocytes with N-acetylcysteine. Voriconazole increases oxidative stress in keratinocytes by directly inhibiting catalase leading to lower intracellular NADPH levels and the triazole moieties in voriconazole are critical for inhibiting catalase. Furthermore, voriconazole is shown to promote UV-induced dysplasia in an in vivo model. Together, these data demonstrate that voriconazole potentiates oxidative stress in UV-irradiated keratinocytes through catalase inhibition. Use of antioxidants may mitigate the pro-oncogenic effects of voriconazole.

Subcutaneous Fungal Infection Caused by a Non-sporulating Strain of Corynespora cassiicola Successfully Treated with Terbinafine

Corynespora cassiicola is a common plant pathogen, but C. cassiicola infection in human hosts is extremely rare. In this report, we present an 84-year-old male with long-term use of inhaled corticosteroids who developed a subcutaneous infection caused by C. cassiicola. The organism was isolated from both wound culture and biopsy specimen from the skin lesion. However, no microscopic diagnostic characters could be obtained because the isolates failed to sporulate on different culture media. Molecular diagnosis by amplification and sequencing of the internal transcribed spacer regions of ribosomal DNA was performed, and the sequences of the isolates were identical to those of C. cassiicola. The patient was treated successfully with oral terbinafine therapy for 12 weeks. In this report, we also review the epidemiology, clinical and therapeutic facets of cutaneous C. cassiicola infection.

Insight into the Significance of Aspergillus fumigatus cyp51A Polymorphisms

Triazole antifungal compounds are the first treatment choice for invasive aspergillosis. However, in the last decade the rate of azole resistance among Aspergillus fumigatus strains has increased notoriously. The main resistance mechanisms are well defined and mostly related to point mutations of the azole target, 14-α sterol demethylase (cyp51A), with or without tandem repeat integrations in the cyp51A promoter. Furthermore, different combinations of five Cyp51A mutations (F46Y, M172V, N248T, D255E, and E427K) have been reported worldwide in about 10% of all A. fumigatus isolates tested. The azole susceptibility profile of these strains shows elevated azole MICs, although on the basis of the azole susceptibility breakpoints, these strains are not considered azole resistant. The purpose of the study was to determine whether these cyp51A polymorphisms (single nucleotide polymorphisms [SNPs]) are responsible for the azole susceptibility profile and whether they are reflected in a poorer azole treatment response in vivo that could compromise patient treatment and outcome. A mutant with a cyp51A deletion was generated and became fully susceptible to all azoles tested. Also, three cyp51A gene constructions with different combinations of SNPs were generated and reintroduced into an azole-susceptible wild-type (WT) strain (the ΔakuB^KU80 strain). The alternative model host Galleria mellonella was used to compare the virulence and voriconazole response of G. mellonella larvae infected with A. fumigatus strains with WT cyp51A or cyp51A with SNPs. All strains were pathogenic in G. mellonella larvae, although they did not respond similarly to voriconazole therapeutic doses. Finally, the full genomes of these strains were sequenced and analyzed in comparison with those of A. fumigatus WT strains, revealing that they belong to different strain clusters or lineages.

Deadly Sphenoid Fungus-Isolated Sphenoid Invasive Fungal Rhinosinusitis: A Case Report

INTRODUCTION

Acute invasive fungal rhinosinusitis (AIFRS) is a potentially fatal infection, usually affecting immunocompromised patients. Isolated sphenoid sinus involvement is rare and has been reported in only a few cases. We discuss the clinical characteristics, histopathologic features, and differential diagnosis of AIFRS of the sphenoid sinus.

CASE PRESENTATION

A 57-year-old man with a history of refractory non-Hodgkin lymphoma and neutropenia presented with a 1-week duration of left-sided headache and ipsilateral cheek paresthesia. Nasal endoscopy showed mucoid drainage from the sphenoethmoidal recess. Magnetic resonance imaging demonstrated left sphenoid mucosal thickening and enhancement along the adjacent skull base. The patient underwent endoscopic sinus surgery with extended sphenoidotomy and débridement. The lateral wall and recess of the left sphenoid sinus demonstrated pale mucosa and fungal debris. Pathologic analysis demonstrated necrotic tissue and fungal hyphae with angioinvasion. Microbiology studies isolated Aspergillus fumigatus. The right maxillary sinus contained a synchronous fungal ball, which was removed during surgery; there was no evidence of tissue necrosis or invasive fungus in the maxillary sinus. He was treated with long-term voriconazole therapy, and 6-month follow-up showed disease resolution.

DISCUSSION

AIFRS should be considered in the differential diagnosis of immunocompromised patients with nonspecific sinonasal symptoms. Usually, AIFRS is diffuse with multiple sinus involvement; however, isolated sphenoid AIFRS can occur. This is one of the few cases of AIFRS demonstrating isolated sphenoid involvement and is thought to be the first case showing a synchronous noninvasive fungal ball of another sinus cavity. Prompt recognition and surgical treatment may be curative and lifesaving.

In Vitro and In Vivo Efficacy of a Novel and Long-Acting Fungicidal Azole, PC1244, on Aspergillus fumigatus Infection

The antifungal effects of the novel triazole PC1244, designed for topical or inhaled administration, against Aspergillus fumigatus were tested in a range of in vitro and in vivo studies. PC1244 demonstrated potent antifungal activities against clinical A. fumigatus isolates (n = 96) with a MIC range of 0.016 to 0.25 μg/ml, whereas the MIC range for voriconazole was 0.25 to 0.5 μg/ml. PC1244 was a strong tight-binding inhibitor of recombinant A. fumigatus CYP51A and CYP51B (sterol 14α-demethylase) enzymes and strongly inhibited ergosterol synthesis in A. fumigatus with a 50% inhibitory concentration of 8 nM. PC1244 was effective against a broad spectrum of pathogenic fungi (MIC range, <0.0078 to 2 μg/ml), especially Aspergillus terreus, Trichophyton rubrum, Candida albicans, Candida glabrata, Candida krusei, Cryptococcus gattii, Cryptococcus neoformans, and Rhizopus oryzae. PC1244 also proved to be quickly absorbed into both A. fumigatus hyphae and bronchial epithelial cells, producing persistent antifungal effects. In addition, PC1244 showed fungicidal activity (minimum fungicidal concentration, 2 μg/ml) which indicated that it was 8-fold more potent than voriconazole. In vivo, once-daily intranasal administration of PC1244 (3.2 to 80 μg/ml) to temporarily neutropenic, immunocompromised mice 24 h after inoculation with itraconazole-susceptible A. fumigatus substantially reduced the fungal load in the lung, the galactomannan concentration in serum, and circulating inflammatory cytokine levels. Furthermore, 7 days of extended prophylaxis with PC1244 showed in vivo effects superior to those of 1 day of prophylactic treatment, suggesting accumulation of the effects of PC1244. Thus, PC1244 has the potential to be a novel therapy for the treatment of A. fumigatus infection in the lungs of humans.

[CYP2C19 genetic polymorphism and monitoring voriconazole plasma concentrations in the treatment and prevention of invasive fungal disease for hematological patients]

Objective: To evaluate the effects of CYP2C19 genetic polymorphism on the plasma concentration of voriconazole in patients with hematological disease and the value of serial monitoring plasma concentrations in the treatment and prevention of invasive fungal disease (IFD). Methods: From January 2016 to December 2016, 65 hematological patients who received voriconazole intravenous administration for the treatment of invasive fungal disease were enrolled in this study. The population CYP2C19 polymorphism of voriconazole were performed using PCR-Pyrosequencing. The trough plasma concentrations of vriconazole (Ctrough) was detected by ultra performance liquid chromatography tandem mass spectrometry. Results: Based on the genotype analysis, 65 subjects were identified as extensive metabolizers' group (30 cases) and poor metabolizers' group (35 cases). The Ctrough of the 65 patients were detected for 169 times totally, and there was a significant difference of Ctrough values between the two groups [0.98(0.38-2.08) mg/L vs 2.19(1.53-4.27) mg/L, z=10.286, P<0.001]. The medium of Ctrough in 65 hematological patients were described. Lack of response to therapy was more frequent in patients with voriconazole levels <1.5 mg/L (50.0%) than in those with voriconazole levels >1.5 mg/L (20.5%) (P=0.052). And the risk of adverse events was more frequent in patients with voriconazole levels >5.5 mg/L (80.0%) than in those with voriconazole levels ≤5.5 mg/L (8.3%) (χ2=11.689, P=0.020). Conclusion: Patients with CYP2C19 wild-type phenotype are extensive metabolizers, their Ctrough of voriconazole are significantly lower than patients with CYP2C19 non-wild-type phenotype (poor metabolizers). Appropriate concentrations of vriconazole can improve the efficacy and safety during treatment.

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.

Acute Progressive Visual Loss in a Case of Acute Myeloid Leukemia: Challenges in the Utility of Molecular Tests in Early Diagnose of Cytomegalovirus Retinitis

Cytomegalovirus (CMV) retinitis is one of the rare but debilitating presentations of the CMV infection in children with leukemia. Herein, we report a 12-year-old boy with acute myeloid leukemia complicated by rapid progressive visual loss during relapse of leukemia. The definite diagnosis of CMV retinitis was made after vitreous aspiration. Despite prompt treatment and ophthalmologic intervention, he died because of AML relapse. Viral infections, especially cytomegalovirus infection, may present with vague clinical pictures during any time of chemotherapy, which may not be easily distinguishable from bacterial or fungal retinitis and also chemotherapy-induced retinopathies. Clinician should consider CMV retinitis in seropositive patients especially those without detectable viremia.

Therapeutic drug monitoring of voriconazole for treatment and prophylaxis of invasive fungal infection in children

Voriconazole therapeutic drug monitoring is not consistently recommended due to its high interpatient and intrapatient variability. Here, we aimed to describe our experience with voriconazole for treatment and prophylaxis of invasive fungal infections in paediatric patients. A fully validated high-performance liquid chromatography-mass spectrometry method was used to quantify voriconazole concentration in plasma, at the end of dosing interval. A high interindividual variability was shown. We enrolled 237 children, 83 receiving intravenous and 154 oral voriconazole. A positive correlation between drug dose and drug plasma exposure was observed. Considering intravenous route, patients with higher serum creatinine had higher voriconazole concentrations; a positive correlation was found among drug exposure and age. Sex significantly influenced drug levels: males had higher median drug concentrations than females (P < 0.001). Close voriconazole pharmacokinetics monitoring should help individualize antifungal therapy for children.

In Vivo Biomarker Analysis of the Effects of Intranasally Dosed PC945, a Novel Antifungal Triazole, on Aspergillus fumigatus Infection in Immunocompromised Mice

PC945 is a novel triazole optimized for lung delivery, and the objective of this study is to determine the effects of intranasally dosed PC945 on Aspergillus fumigatus infection and associated biomarkers in immunocompromised mice. PC945, posaconazole, or voriconazole was administered intranasally once daily on days 0 to 3 (early intervention) or days 1 to 3 (late intervention) postinfection in temporarily neutropenic A/J mice infected intranasally with A. fumigatus, and bronchoalveolar lavage fluid (BALF) and serum were collected on day 3. The effects of extended prophylaxis treatment (daily from days −7 to +3 or days −7 to 0) were also compared with those of the shorter treatment regimens (days −1 to +3 or days −1 and 0). Early and late interventions with PC945 (2.8 to 350 μg/mouse; approximately 0.11 to ∼14 mg/kg of body weight) were found to inhibit lung fungal loads and to decrease the concentrations of galactomannan (GM) in both BALF and serum as well as several biomarkers in BALF (interferon gamma [IFN-γ], interleukin-17 [IL-17], and malondialdehyde) and serum (tumor necrosis factor alpha [TNF-α] and IL-6) in a dose-dependent manner and were >3- and >47-fold more potent than intranasally dosed posaconazole and voriconazole, respectively. Furthermore, extended prophylaxis with low-dose PC945 (0.56 μg/mouse; 0.022 mg/kg) was found to inhibit fungal loads and to decrease the concentrations biomarkers more potently than did the shorter treatment regimens. Thus, PC945 dosed intranasally once daily showed potent antifungal effects, and the effects of PC945 accumulated upon repeat dosing and were persistent. Therefore, PC945 has the potential to be a novel inhaled therapy for the treatment of A. fumigatus infection in humans.

In Vitro and In Vivo Antifungal Profile of a Novel and Long-Acting Inhaled Azole, PC945, on Aspergillus fumigatus Infection

The profile of PC945, a novel triazole antifungal designed for administration via inhalation, was assessed in a range of in vitro and in vivo studies. PC945 was characterized as a potent, tightly binding inhibitor of Aspergillus fumigatus sterol 14α-demethylase (CYP51A and CYP51B) activity (50% inhibitory concentrations [IC₅₀s], 0.23 μM and 0.22 μM, respectively) with characteristic type II azole binding spectra. Against 96 clinically isolated A. fumigatus strains, the MIC values of PC945 ranged from 0.032 to >8 μg/ml, while those of voriconazole ranged from 0.064 to 4 μg/ml. Spectrophotometric analysis of the effects of PC945 against itraconazole-susceptible and -resistant A. fumigatus growth yielded IC₅₀ (determined based on optical density [OD]) values of 0.0012 to 0.034 μg/ml, whereas voriconazole (0.019 to >1 μg/ml) was less effective than PC945. PC945 was effective against a broad spectrum of pathogenic fungi (with MICs ranging from 0.0078 to 2 μg/ml), including Aspergillus terreus, Trichophyton rubrum, Candida albicans, Candida glabrata, Candida krusei, Cryptococcus gattii, Cryptococcus neoformans, and Rhizopus oryzae (1 or 2 isolates each). In addition, when A. fumigatus hyphae or human bronchial cells were treated with PC945 and then washed, PC945 was found to be absorbed quickly into both target and nontarget cells and to produce persistent antifungal effects. Among temporarily neutropenic immunocompromised mice infected with A. fumigatus intranasally, 50% of the animals survived until day 7 when treated intranasally with PC945 at 0.56 μg/mouse, while posaconazole showed similar effects (44%) at 14 μg/mouse. This profile affirms that topical treatment with PC945 should provide potent antifungal activity in the lung.

Voriconazole Composited Polyvinyl Alcohol/Hydroxypropyl-β-Cyclodextrin Nanofibers for Ophthalmic Delivery

Voriconazole (VRC) incorporated in composited polyvinyl alcohol (PVA)/hydroxypropyl-β-cyclodextrin (HPβCD) blended nanofibers were produced via electrospinning for efficient ophthalmic delivery. The VRC loading capacity increased with increasing HPβCD content. The optimal solution for electrospinning consisted of 8% (w/v) PVA, 4% (w/v) HPβCD and 0.5% (w/v) VRC. The nanofibers exhibited bead-free average fiber diameters of 307±31 nm and VRC was released in vitro in a sustained manner. The VRC nanofibers were characterized by infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The proton nuclear magnetic resonance (1H-NMR) was used to analyze the molar ratio of HPβCD/VRC in the nanofibers. Compared with a VRC solution, the nanofibers significantly prolonged the half life, and increased the bioavailability of VRC in rabbit tears. No obvious signs of irritation were observed after application in the conjunctival sac. VRC nanofibers are promising for ophthalmic drug delivery and further pharmacodynamics studies are needed.

Drug-Drug Interaction Associated with Mold-Active Triazoles among Hospitalized Patients

The majority of hospitalized patients receiving mold-active triazoles are at risk of drug-drug interactions (DDIs). Efforts are needed to increase awareness of DDIs that pose a serious risk of adverse events. Triazoles remain the most commonly utilized antifungals. Recent developments have included the mold-active triazoles (MATs) itraconazole, voriconazole, and posaconazole, which are first-line agents for the treatment of filamentous fungal infections but have the potential for DDIs. This objective of this study was to evaluate the prevalence of triazole DDIs. Hospitalized U.S. adults with MAT use were identified in the Cerner HealthFacts database, which contained data from over 150 hospitals (2005 to 2013). The severities of DDIs with MATs were categorized, using drug labels and the drug information from the Drugdex system (Thompson Micromedex), into four groups (contraindicated, major, moderate, and minor severity). DDIs of minor severity were not counted. A DDI event was considered to have occurred if the following two conditions were met: (i) the patient used at least one drug with a classification of at least a moderate interaction with the MAT during the hospitalization and (ii) there was a period of overlap between the administration of the MAT and that of the interacting drug of at least 1 day. A total of 6,962 hospitalizations with MAT use were identified. Among them, 88% of hospitalizations with voriconazole use, 86% of hospitalizations with itraconazole use, and 93% of hospitalizations with posaconazole use included the use of a concomitant interacting drug. A total of 68% of hospitalizations with posaconazole use, 34% of hospitalizations with itraconazole use, and 20% of hospitalizations with voriconazole use included the use of at least one drug with a DDI of contraindicated severity. A total of 83% of hospitalizations with posaconazole use, 61% of hospitalizations with itraconazole use, and 82% of hospitalizations with voriconazole use included the use of at least one drug that resulted in a severe DDI. The findings of this study demonstrate that a majority of hospitalized patients receiving MAT are at risk for severe drug-drug interactions and highlight the need for antifungal stewardship.

How to manage aspergillosis in non-neutropenic intensive care unit patients

Invasive aspergillosis has been mainly reported among immunocompromised patients during prolonged periods of neutropenia. Recently, however, non-neutropenic patients in the ICU population have shown an increasing risk profile for aspergillosis. Associations with chronic obstructive pulmonary disease and corticosteroid therapy have been frequently documented in this cohort. Difficulties in achieving a timely diagnosis of aspergillosis in non-neutropenic patients is related to the non-specificity of symptoms and to lower yields with microbiological tests compared to neutropenic patients. Since high mortality rates are typical of invasive aspergillosis in critically ill patients, a high level of suspicion and prompt initiation of adequate antifungal treatment are mandatory. Epidemiology, risk factors, diagnostic algorithms, and different approaches in antifungal therapy for invasive aspergillosis in non-neutropenic patients are reviewed.

Drug-drug interaction between voriconazole and oral hypoglycemic agents in diabetic rats

Objective:

The objective was to study the of drug-drug interaction between voriconazole and oral hypoglycemic agents in normal and alloxan induced diabetic rats.

Materials and Methods:

The study was designed in two phases. In the first phase, influence of glibenclamide (0.45 mg/kg, p.o.) and pioglitazone (2.7 mg/kg, p.o. once daily) on blood glucose levels in normoglycemic rats was studied and then influence of voriconazole (18 mg/kg, p.o. twice daily.) pre-treatment on the hypoglycemic activity studied. Simultaneously the influence of voriconazole treatment for seven consecutive days (per se effect) on blood glucose levels was also studied in normoglycemic rats. In the second phase of the study alloxan-induced diabetic rats were used to find out the influence of voriconazole pre-treatment on glibenclamide and pioglitazone induced hypoglycemic effect in pathophysiological condition. Blood samples were collected from retro orbital plexus at regular intervals of 0.0, 0.5, 1.0, 2.0, 4.0, 8.0, 12.0, 18.0 and 24.0 h after drug treatment. All the blood samples were analyzed for plasma glucose by glucose oxidase peroxidase method (GOD/POD).

Results:

The therapeutic dose of voriconazole potentiates the hypoglycemic activity of glibenclamide and pioglitazone both in normoglycemic and diabetic rats respectively.

Conclusion:

The results indicate that the dose of oral hypoglycemic agents needs to be adjusted if co-administered with voriconazole.

Empirical voriconazole therapy for febrile neutropenic patients with hematological disorders: a prospective multicenter trial in Japan

An open-label, prospective, multicenter study was conducted between October 2006 and March 2010 to assess the efficacy and safety of intravenous voriconazole (VRCZ) as empirical therapy for antibiotic-refractory febrile neutropenia in Japanese patients with hematological disorders. In addition, to find the patient groups that may benefit from antifungal therapy, the definition of invasive fungal infection proposed by EORTC/MSG (2002) was assessed in this study. Plasma (1-3)-β-d-glucan and Aspergillus PCR in blood were also measured to improve the diagnostic accuracy. A total of 103 patients (median age, 59 years), including 25 undergoing induction chemotherapies and 19 allogeneic hematopoietic cell transplants, were evaluable. Sixty-nine percent of the patients achieved resolution of clinical symptoms and 31 % achieved treatment success, defined as fulfilling the previously described five-part composite endpoint. Although VRCZ was discontinued in 9.7 % of the patients because of adverse effects, all the patients recovered soon after discontinuation of VRCZ. The treatment success rate of VRCZ appeared to be higher in patients categorized as “not classified” compared with “possible invasive fungal disease” according to the EORTC/MSG criteria. Moreover, six “not classified” patients were positive for either plasma (1-3)-β-d-glucan (n = 5) or Aspergillus PCR in blood (n = 2). The present study demonstrates that empirical VRCZ therapy is safe and effective in Japanese patients. Additionally, (1-3)-β-d-glucan and Aspergillus PCR tests were expected to provide additional information on the diagnosis of invasive fungal infections.

Effect of PTX3 and voriconazole combination in a rat model of invasive pulmonary aspergillosis

This study evaluated the pharmacological activity of PTX3, administered in combination with voriconazole, in a rat model of pulmonary aspergillosis. The data indicated additive therapeutic activities of these compounds, as demonstrated by the amelioration of respiratory function changes, reduction of lung fungal burden, and increased survival. Overall, we provide clear evidence that the combination of PTX3 with a suboptimal dose of voriconazole might represent a therapeutic option under those clinical conditions where the use of voriconazole alone is not warranted for efficacy and tolerability reasons.