Invasive fungal infections among organ transplant recipients: results of the Transplant-Associated Infection Surveillance Network (TRANSNET)

Aspergillus tubingensis and Aspergillus niger as the dominant black Aspergillus, use of simple PCR-RFLP for preliminary differentiation

This work aimed to identify the species distribution of common clinical and environmental isolates of black Aspergilli based on simple restriction fragment length polymorphism (RFLP) analysis of the β-tubulin gene. A total of 149 clinical and environmental strains of black Aspergilli were collected and subjected to preliminary morphological examination. Total genomic DNAs were extracted, and PCR was performed to amplify part of the β-tubulin gene. At first, 52 randomly selected samples were species-delineated by sequence analysis. In order to distinguish the most common species, PCR amplicons of 117 black Aspergillus strains were identified by simple PCR-RFLP analysis using the enzyme TasI. Among 52 sequenced isolates, 28 were Aspergillus tubingensis, 21 Aspergillus niger, and the three remaining isolates included Aspergillus uvarum, Aspergillus awamori, and Aspergillus acidus. All 100 environmental and 17 BAL samples subjected to TasI-RFLP analysis of the β-tubulin gene, fell into two groups, consisting of about 59% (n=69) A. tubingensis and 41% (n=48) A. niger. Therefore, the method successfully and rapidly distinguished A. tubingensis and A. niger as the most common species among the clinical and environmental isolates. Although tardy, the Ehrlich test was also able to differentiate A. tubingensis and A. niger according to the yellow color reaction specific to A. niger. A. tubingensis and A. niger are the most common black Aspergillus in both clinical and environmental isolates in Iran. PCR-RFLP using TasI digestion of β-tubulin DNA enables rapid screening for these common species.

Antifungal Effects of Common Mouthwashes on Candida Strains Colonized in the Oral Cavities of Liver Transplant Recipients in South Iran in 2014

BACKGROUND

Among the opportunistic microorganisms, fungi, particularly Candida, play an important role in the mortality of transplant recipients. Thus, controlling and preventing fungal colonizations in various parts of the body, including the oral cavity, can reduce the possibility of post-transplant invasive fungal infections. This can be done simply by using mouthwashes.

OBJECTIVES

The current study aimed to determine the prevalence of fungal species of Candida within the oral cavities of liver transplant recipients, and to evaluate the effects on Candida colonization of different exposure times to common mouthwashes.

PATIENTS AND METHODS

Specimens were taken from the oral cavities of 101 liver transplant recipients who were referred to our clinic for their first monthly examination. After cultivation and DNA extraction, yeast strains were identified with the RFLP technique. Each strain's susceptibility to 0.2% chlorhexidine, Vi-One, Oral-B, Nanosil D1, and Nystatin mouthwashes was determined based on the CLSI M27-A2 standard method.

RESULTS

The obtained data were analyzed using SPSS. Out of 101 samples from liver transplant recipients, 68 cases showed fungi growing within the culture media (67.4%). C. albicans and C. glabrata, respectively, were the first and second most frequent types. Mouthwash susceptibility tests revealed that their antifungal effects over 60 seconds were significantly higher than with an exposure time of 30 seconds. At both 30 and 60 seconds, chlorhexidine was significantly the most efficient.

CONCLUSIONS

Chlorhexidine mouthwash with an exposure time of 60 seconds or more is suggested as an effective antifungal agent to be included in the medication regimen of liver transplant patients pre- and postoperatively, in order to prevent fungal colonization and subsequent systemic infections.

Polymicrobial pulmonary infection in patients with hematological malignancies: prevalence, co-pathogens, course and outcome

PURPOSE

The frequency and clinical significance of polymicrobial pneumonia in patients with hematological malignancies (HM) are poorly understood. The aim of the present study is to describe the prevalence, risk factors, clinical characteristics, and outcome of patients with HM and polymicrobial pneumonia.

METHODS

Over a 5 year period, 436 consecutive adult patients with HM and pulmonary infiltrates underwent diagnostic fiberoptic bronchoscopy with bronchoalveolar lavage. For 219 patients an infectious etiology was diagnosed, of them 45 (20.5 %) had polymicrobial etiology. Risk factors, clinical course and outcome of polymicrobial pulmonary infection in patients with HM were established.

RESULTS

45 patients with HM were identified with polymicrobial pulmonary infection, 39 of them with two pathogens, and 6 with three. The most common co-pathogen identified was Aspergillus sp. (87 %). Allogeneic hematopoietic stem cell transplantation (HSCT) and graft versus host disease (GVHD) were predictors of polymicrobial infection. Compared to patients with monomicrobial pneumonia, patients with polymicrobialpulmonary infection had a more severe clinical course with more dyspnea (69 vs. 49 %, P = 0.016), hemoptysis (16 vs. 7 %, P = 0.065) and more required respiratory support (27 vs. 17 %, P = 0.125). In-hospital mortality was significantly higher in patients with polymicrobial pulmonary infection than in patients with monomicrobial pulmonary infection (49 vs. 19 %, P < 0.001).

CONCLUSIONS

Polymicrobial pulmonary infection occurs quite frequently in patients with HM, especially in allogeneic HSCT recipients and in patients with GVHD. The clinical course of polymicrobial pulmonary infection is severe and mortality approaches 50 %. The clinician taking care of these patients should always look for additional copathogens in profoundly immunosuppressed patients with pneumonia.

[Specific infections in organ transplantation]

This article is concerned with the important topic of infections associated with organ transplantation and includes a discussion on four subtopics. The first section describes the current options in the prevention and therapy of viral hepatitis in association with liver transplantation. Infections with hepatitis B, C, D (delta) and E are discussed with special emphasis on the interferon-free treatment of hepatitis C with the new antiviral drugs.The second section deals with Pseudomonas aeruginosa (PA) infections following lung transplantation (LuTx), which is one of the most frequently detected pathogens in the airway after LuTx. Patients with cystic fibrosis are particularly affected. This is important because studies have shown a clear correlation between chronic PA infections after LuTx and development of chronic transplant failure. Even if the data are still sparse, recommendations on prevention and therapeutic strategies are given. The theme of the third section is the high importance of viral infections after kidney transplantation. In addition to acquired infections, the transplanted organ as well as the recipient can be the source of the infection. The better the transplanted organ is tolerated under moderate immunosuppression, the less common and severe virus infections are. The focus of this section is on three common pathogens: cytomegalovirus, polyomavirus BK and hepatitis viruses.The final section deals with Aspergillus infections following transplantation of various organs. In this context Aspergillus spp. are one of the most commonly occurring fungal diseases. The epidemiology, risk factors, diagnostics, prophylaxis and therapy of invasive aspergillosis are presented.

Bloodstream infections after solid-organ transplantation

Solid-organ transplantation (SOT) has become the preferred strategy to treat a number of end-stage organ disease, because a continuous improvement in survival and quality of life. While preventive strategies has decreased the risk for classical opportunistic infections (such as viral, fungal and parasite infections), bacterial infections, and particularly bloodstream infections (BSIs) remain the most common and life-threatening complications in SOT recipients. The source of BSI after transplant depends on the type of transplantation, being urinary tract infection, pneumonia, and intraabdominal infections the most common infections occurring after kidney, lung and liver transplantation, respectively. The risk for candidemia is higher in abdominal-organ than in thoracic-organ transplantation. Currently, the increasing prevalence of multi-drug resistant (MDR) Gram-negative pathogens, such as extended-spectrum betalactamase-producing Enterobacteriaciae and carbapenem-resistant Klebsiella pneumoniae, is causing particular concerns in SOT recipients, a population which presents several risk factors for developing infections due to MDR organisms. The application of strict preventive policies to reduce the incidence of post transplant BSIs and to control the spread of MDR organisms, including the implementation of specific stewardship programs to avoid the overuse of antibiotics and antifungal drugs, are essential steps to reduce the impact of post transplant infections on allograft and patient outcomes.

Invasive Fungal Infections After Kidney Transplantation: A Single-center Experience

INTRODUCTION

Invasive fungal infections (IFI) affecting transplant recipients are associated with increased mortality and graft dysfunction.

OBJECTIVE

Describe the frequency, clinical features, and outcomes of IFI (except pneumocystis infection) in kidney transplant recipients.

METHOD

Single-center descriptive study including every kidney transplant recipient with a culture-proven or probable IFI between 2003 and 2013, according to the EORTC-MSG criteria.

RESULTS

We identified 45 IFI. There were 13 cases of invasive candidiasis (C. albicans: 6 and non-C. albicans candidial spp.: 7), 11 cases of pulmonary aspergillosis (A. fumigatus: 9 and A. flavus: 2); 11 cases of subcutaneous mycosis (Alternaria spp.: 9, Paecilomyces spp.: 1, and Pseudallescheria spp.: 1); 7 cases of cryptococcosis; 2 cases of pneumonia by non-Aspergillus molds (Mucor spp.: 1 and Cunninghamella spp.: 1); and 1 case of Geotrichum capitatum pneumonia. All patients were recipients from deceased donors. Six cases occurred in the first 3 months post-transplant, 15 cases between the third and twelfth months, and 21 cases after the twelfth month. Treatment options were fluconazole for Candida infections, voriconazole or caspofungin for aspergillosis, liposomal amphotericin for cryptococcosis, and itraconazole plus excision or cryotherapy for subcutaneous mycosis. Fifteen patients died (33%). Mortality rates were 15% for invasive candidiasis, 45% for aspergillosis, 71% for cryptococcosis, 100% for non-Aspergillus molds and G. capitatum pneumonia, and 0% for subcutaneous mycosis. Six patients who survived (14%) started regular hemodialysis.

CONCLUSION

IFI still have a high mortality and morbidity in kidney transplant recipients, as verified in this report. We reinforce the need for a high index of suspicion and prompt treatment.

Risks and Epidemiology of Infections After Lung or Heart–Lung Transplantation

Nowadays, lung transplantation is an established treatment option of end-stage pulmonary parenchymal and vascular disease. Post-transplant infections are a significant contributor to overall morbidity and mortality in the lung transplant recipient that, in turn, are higher than in other solid organ transplant recipients. This is likely due to several specific factors such as the constant exposure to the outside environment and the colonized native airway, and the disruption of usual mechanisms of defense including the cough reflex, bronchial circulation, and lymphatic drainage. This chapter will review the common infections that develop in the lung or heart–lung transplant recipient, including the general risk factors for infection in this population, and specific features of prophylaxis and treatment for the most frequent bacterial, viral, and fungal infections. The effects of infection on lung transplant rejection will also be discussed.

Approach to the Solid Organ Transplant Patient with Suspected Fungal Infection

In solid organ transplant (SOT) recipients, invasive fungal infections (IFIs) are associated with significant morbidity and mortality. Detection of IFIs can be difficult because the signs and symptoms are similar to those of viral or bacterial infections, and diagnostic techniques have limited sensitivity and specificity. Clinicians must rely on knowledge of the patient's risk factors for fungal infection to make a diagnosis. The authors describe their approach to the SOT recipient with suspected fungal infection. The epidemiology of IFIs in the SOT population is reviewed, and a syndromic approach to suspected IFI in SOT recipients is described.

Whole animal HTS of small molecules for antifungal compounds

INTRODUCTION

The high morbidity and mortality among patients with invasive fungal infections and the growing problem of fungal resistance have resulted in an urgent need for new antifungal agents.

AREAS COVERED

This review covers the importance of antifungal drug discovery with an emphasis on whole-animal high-throughput techniques. More specifically, the authors focus on Caenorhabditis elegans, as a substitute model host and discuss C. elegans as an alternative model host for the study of microbial pathogenesis and the identification of novel antifungal compounds.

EXPERT OPINION

There are significant advantages from using the substitute model host C. elegans in high-throughput drug discovery. The C. elegans-microbe model provides a whole animal system where host-pathogen interactions can be studied along with the evaluation of antimicrobial efficacy of compounds. This approach allows the study of compound characteristics, such as toxicity and solubility, during the initial screen and compounds discovered using C. elegans are affective in mammalian models.

Putative invasive pulmonary aspergillosis in critically ill patients with chronic obstructive pulmonary disease: a matched cohort study

Introduction

Patients with advanced chronic obstructive pulmonary disease (COPD) are at risk for developing invasive pulmonary aspergillosis. A clinical algorithm has been validated to discriminate colonization from putative invasive pulmonary aspergillosis (PIPA) in Aspergillus-positive respiratory tract cultures of critically ill patients. We focused on critically ill patients with COPD who met the criteria for PIPA.

Methods

This matched cohort study included critically ill patients with COPD from two university hospital intensive care units (ICUs). We studied the risk factors for PIPA as well as the impact of PIPA on short- and long-term outcomes. Whether PIPA was associated with a pattern of bacterial colonization and/or infection 6 months before and/or during ICU stay was assessed. In addition, antifungal strategies were reviewed.

Results

Fifty cases of PIPA in critically ill patients with COPD in the ICU were matched with one hundred control patients with COPD. The ICU short- and the long-term (at 1 year) mortality were significantly increased in the PIPA group (p < 0.001 for all variables). PIPA was a strong independent risk factor for mortality in the ICU (odds ratio 7.44, 95 % confidence interval 2.93–18.93, p < 0.001) before vasopressor therapy, renal replacement therapy, and duration of mechanical ventilation. Before ICU admission, the use of corticosteroids and antibiotics significantly increased the risk of PIPA (p = 0.004 and p < 0.001, respectively). No significant difference in bacterial etiologic agents responsible for colonization and/or infection was found between the groups. Antifungal treatment was started in 64 % of PIPA cases, with a poor impact on the overall outcome.

Conclusions

PIPA was a strong death predictor in critically ill patients with COPD. The use of corticosteroids and antibiotics before ICU admission was a risk factor for PIPA. PIPA was not associated with a specific bacterial pattern of colonization or infection. Prompting antifungal treatment in critically ill patients with COPD who have PIPA may not be the only factor involved in prognosis reversal.

A pseudo-outbreak of disseminated cryptococcal disease after orthotopic heart transplantation

Cryptococcal infection is the third most common invasive fungal infection (IFI) among solid-organ transplant (SOT) recipients and is considered an important opportunistic infection due to its significant morbidity and mortality. To determine whether a cluster of cryptococcosis in heart transplant patients was of nosocomial nature, three cases of orthotopic heart transplant recipients with postoperative disseminated cryptococcal infection were investigated and paired with an environmental survey in a tertiary care hospital. The infection prevention department conducted a multidisciplinary investigation, which did not demonstrate any evidence of health care-associated environmental exposure. Moreover, multilocus sequence typing showed that one isolate was unique and the two others, although identical, were not temporally related and belong to the most common type seen in the Southern US. Additionally, all three patients had preexisting abnormalities of the CT chest scan and various degrees of acute and chronic rejection. Reactivation was suggested in all three patients. Screening methods may be useful to identify at risk patients and trigger a prophylactic or preemptive approach. However, more data is needed.

Respiratory Failure due to Possible Donor-Derived Sporothrix schenckii Infection in a Lung Transplant Recipient

Background. De novo and donor-derived invasive fungal infections (IFIs) contribute to morbidity and mortality in solid organ transplant (SOT) recipients. Reporting of donor-derived IFIs (DDIFIs) to the Organ Procurement Transplant Network has been mandated since 2005. Prior to that time no systematic monitoring of DDIFIs occurred in the United States. Case Presentation. We report a case of primary graft dysfunction in a 49-year-old male lung transplant recipient with diffuse patchy bilateral infiltrates likely related to pulmonary Sporothrix schenckii infection. The organism was isolated from a bronchoalveolar lavage on the second day after transplantation. Clinical and radiographic responses occurred after initiation of amphotericin B lipid formulation. Conclusion. We believe that this was likely a donor-derived infection given the early timing of the Sporothrix isolation after transplant in a bilateral single lung transplant recipient. This is the first case report of sporotrichosis in a lung transplant recipient. Our patient responded well to amphotericin induction therapy followed by maintenance therapy with itraconazole. The implications of donor-derived fungal infections and Sporothrix in transplant recipients are reviewed. Early recognition and management of these fungi are essential in improving outcomes.

Improved Detection of Invasive Pulmonary Aspergillosis Arising during Leukemia Treatment Using a Panel of Host Response Proteins and Fungal Antigens

Invasive pulmonary aspergillosis (IPA) is an opportunistic fungal infection in patients undergoing chemotherapy for hematological malignancy, hematopoietic stem cell transplant, or other forms of immunosuppression. In this group, Aspergillus infections account for the majority of deaths due to mold pathogens. Although early detection is associated with improved outcomes, current diagnostic regimens lack sensitivity and specificity. Patients undergoing chemotherapy, stem cell transplantation and lung transplantation were enrolled in a multi-site prospective observational trial. Proven and probable IPA cases and matched controls were subjected to discovery proteomics analyses using a biofluid analysis platform, fractionating plasma into reproducible protein and peptide pools. From 556 spots identified by 2D gel electrophoresis, 66 differentially expressed post-translationally modified plasma proteins were identified in the leukemic subgroup only. This protein group was rich in complement components, acute-phase reactants and coagulation factors. Low molecular weight peptides corresponding to abundant plasma proteins were identified. A candidate marker panel of host response (9 plasma proteins, 4 peptides), fungal polysaccharides (galactomannan), and cell wall components (β-D glucan) were selected by statistical filtering for patients with leukemia as a primary underlying diagnosis. Quantitative measurements were developed to qualify the differential expression of the candidate host response proteins using selective reaction monitoring mass spectrometry assays, and then applied to a separate cohort of 57 patients with leukemia. In this verification cohort, a machine learning ensemble-based algorithm, generalized pathseeker (GPS) produced a greater case classification accuracy than galactomannan (GM) or host proteins alone. In conclusion, Integration of host response proteins with GM improves the diagnostic detection of probable IPA in patients undergoing treatment for hematologic malignancy. Upon further validation, early detection of probable IPA in leukemia treatment will provide opportunities for earlier interventions and interventional clinical trials.

Bronchoalveolar Lavage Fluid (1,3)β-D-Glucan for the Diagnosis of Invasive Fungal Infections in Solid Organ Transplantation: A Prospective Multicenter Study

BACKGROUND

Prompt diagnosis of invasive fungal infections (IFI) remains a challenge. (1,3)β-D-glucan detection in bronchoalveolar lavage (BAL) fluid by Fungitell assay aims to further improve upon the test's utility by directly applying it to specimens from the target organ.

METHODS

A prospective multicenter analysis of the Fungitell assay was performed on BAL and serum samples obtained from nonselected solid-organ transplantation patients suffering from probable, proven or no IFI according to the revised criteria of the European Organisation for Research and Treatment of Cancer / Mycosis Study Group.

RESULTS

Two hundred thirty-three BAL and 109 serum specimens from 135 patients with proven, probable, or no IFI were tested. Based on a 100 pg/mL: cutoff per test sensitivity, specificity, positive and negative predictive values were 79.2%, 38.5%, 27.6%, and 86.3% in BALs and 79.2%, 81.8%, 69.2%, and 83.1% in sera investigated.

CONCLUSIONS

The accuracy of the (1,3)β-D-glucan test is marginal so that its utility as a clinical test for early diagnosis of IFI is questionable in the lung transplant population. Although the high negative predictive value of the Fungitell assay in both, BALs and sera, may support exclusion of pulmonary IFI in solid-organ transplantation patients, the low positive predictive value limits its utility as a screening tool for early diagnosis of IFI.

Disseminated mucormycosis with myocardial involvement in a renal transplant recipient

We report the case of a renal transplant recipient with pulmonary and splenic mucormycosis whose demise was accelerated by a myocardial abscess. Once pulmonary and splenic mucormycosis was diagnosed, liposomal amphotericin B was started and immunosuppressant treatments were discontinued. The pulmonary cavities regressed during treatment, but new myocardial and peri-allograft abscesses developed. The myocardial abscess diffusely infiltrated the left ventricular wall and was associated with akinesia, which led to sudden cardiac arrest. This case demonstrates a rare manifestation of mucormycosis and highlights the fatality and invasiveness of this infection.

Phagocytosis-dependent activation of a TLR9-BTK-calcineurin-NFAT pathway co-ordinates innate immunity to Aspergillus fumigatus

Transplant recipients on calcineurin inhibitors are at high risk of invasive fungal infection. Understanding how calcineurin inhibitors impair fungal immunity is a key priority for defining risk of infection. Here, we show that the calcineurin inhibitor tacrolimus impairs clearance of the major mould pathogen Aspergillus fumigatus from the airway, by inhibiting macrophage inflammatory responses. This leads to defective early neutrophil recruitment and fungal clearance. We confirm these findings in zebrafish, showing an evolutionarily conserved role for calcineurin signalling in neutrophil recruitment during inflammation. We find that calcineurin–NFAT activation is phagocytosis dependent and collaborates with NF-κB for TNF-α production. For yeast zymosan particles, activation of macrophage calcineurin–NFAT occurs via the phagocytic Dectin-1–spleen tyrosine kinase pathway, but for A. fumigatus, activation occurs via a phagosomal TLR9-dependent and Bruton's tyrosine kinase-dependent signalling pathway that is independent of MyD88. We confirm the collaboration between NFAT and NF-κB for TNF-α production in primary alveolar macrophages. These observations identify inhibition of a newly discovered macrophage TLR9–BTK–calcineurin–NFAT signalling pathway as a key immune defect that leads to organ transplant-related invasive aspergillosis.

Transcription Factor SomA Is Required for Adhesion, Development and Virulence of the Human Pathogen Aspergillus fumigatus

The transcription factor Flo8/Som1 controls filamentous growth in Saccharomyces cerevisiae and virulence in the plant pathogen Magnaporthe oryzae. Flo8/Som1 includes a characteristic N-terminal LUG/LUH-Flo8-single-stranded DNA binding (LUFS) domain and is activated by the cAMP dependent protein kinase A signaling pathway. Heterologous SomA from Aspergillus fumigatus rescued in yeast flo8 mutant strains several phenotypes including adhesion or flocculation in haploids and pseudohyphal growth in diploids, respectively. A. fumigatus SomA acts similarly to yeast Flo8 on the promoter of FLO11 fused with reporter gene (LacZ) in S. cerevisiae. FLO11 expression in yeast requires an activator complex including Flo8 and Mfg1. Furthermore, SomA physically interacts with PtaB, which is related to yeast Mfg1. Loss of the somA gene in A. fumigatus resulted in a slow growth phenotype and a block in asexual development. Only aerial hyphae without further differentiation could be formed. The deletion phenotype was verified by a conditional expression of somA using the inducible Tet-on system. A adherence assay with the conditional somA expression strain indicated that SomA is required for biofilm formation. A ptaB deletion strain showed a similar phenotype supporting that the SomA/PtaB complex controls A. fumigatus biofilm formation. Transcriptional analysis showed that SomA regulates expression of genes for several transcription factors which control conidiation or adhesion of A. fumigatus. Infection assays with fertilized chicken eggs as well as with mice revealed that SomA is required for pathogenicity. These data corroborate a complex control function of SomA acting as a central factor of the transcriptional network, which connects adhesion, spore formation and virulence in the opportunistic human pathogen A. fumigatus.

Invasive fungal infections affecting immunocompromised patients are emerging worldwide. Among various human fungal pathogens, Aspergillus fumigatus is one of the most common molds causing severe invasive aspergillosis in immunocompromised patients. The conidia, which can evade from innate immunity and adhere to epithelial cells of alveoli in human lungs will start to germinate and cause the disease. Currently, the understanding of the molecular mechanisms of adherence of fungal cells to hosts is scarce. The transcription factor Flo8 controls adhesion to biotic or abiotic surfaces and morphological development in baker’s yeast. Flo8 homologues in the dimorphic human pathogenic yeast Candida albicans or the filamentous plant pathogen Magnaporthe oryzae are required for development and virulence. We found in this study that the Flo8 homologue SomA of A. fumigatus is required for adhesion and conidiation. Two independent invasive aspergillosis assays using chicken eggs or mouse demonstrated that deletion of the corresponding gene resulted in attenuated virulence. SomA represents an important fungal transcription factor at the interface between adherence, asexual spore formation and pathogenicity in an important opportunistic human pathogen.

Pancreatic Candidiasis That Mimics a Malignant Pancreatic Cystic Tumor on Magnetic Resonance Imaging: A Case Report in an Immunocompetent Patient

Candida is a commensal organism that is frequently found in the human gastrointestinal tract. It is the most common organism that causes pancreatic fungal infections. However, magnetic resonance imaging findings of Candida infection in the pancreas have not been described. We report imaging findings of pancreatic candidiasis in a patient in immunocompetent condition. It presented as a multi-septated cystic mass with a peripheral solid component in the background of pancreatitis and restricted diffusion on diffusion-weighted image that mimicked a malignant pancreatic cystic tumor.

Synthetic antimicrobial β-peptide in dual-treatment with fluconazole or ketoconazole enhances the in vitro inhibition of planktonic and biofilm Candida albicans

Fungal infections are a pressing concern for human health worldwide, particularly for immunocompromised individuals. Current challenges such as the elevated toxicity of common antifungal drugs and the emerging resistance towards these could be overcome by multidrug therapy. Natural antimicrobial peptides, AMPs, in combination with other antifungal agents are a promising avenue to address the prevailing challenges. However, they possess limited biostability and susceptibility to proteases, which has significantly hampered their development as antifungal therapies. β-peptides are synthetic materials designed to mimic AMPs while allowing high tunability and increased biostability. In this work, we report for the first time the inhibition achieved in Candida albicans when treated with a mixture of a β-peptide model and fluconazole or ketoconazole. This combination treatment enhanced the biological activity of these azoles in planktonic and biofilm Candida, and also in a fluconazole-resistant strain. Furthermore, the in vitro cytotoxicity of the dual treatment was evaluated towards the human hepatoma cell line, HepG2, a widely used model derived from liver tissue, which is primarily affected by azoles. Analyses based on the LA-based method and the mass-action law principle, using a microtiter checkerboard approach, revealed synergism of the combination treatment in the inhibition of planktonic C. albicans. The dual treatment proved to be fungicidal at 48 and 72 h. Interestingly, it was also found that the viability of HepG2 was not significantly affected by the dual treatments. Finally, a remarkable enhancement in the inhibition of the highly azole-resistant biofilms and fluconazole resistant C. albicans strain was obtained.

Role of New Antifungal Agents in the Treatment of Invasive Fungal Infections in Transplant Recipients: Isavuconazole and New Posaconazole Formulations

Invasive fungal infections are a major cause of morbidity and mortality among solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients. Transplant patients are at risk for such invasive fungal infections. The most common invasive fungal infections are invasive candidiasis in the SOT and invasive aspergillosis in the HSCT. In this article, we will discuss the epidemiology of invasive fungal infections in the transplant recipients and susceptibility patterns of the fungi associated with these infections. Additionally, the pharmacology and clinical efficacy of the new antifungal, isavuconazole, and the new posaconazole formulations will be reviewed. Isavuconazole is a new extended-spectrum triazole that was recently approved for the treatment of invasive aspergillosis and mucormycosis. Advantages of this triazole include the availability of a water-soluble intravenous formulation, excellent bioavailability of the oral formulation, and predictable pharmacokinetics in adults. Posaconazole, a broad-spectrum triazole antifungal agent, is approved for the prevention of invasive aspergillosis and candidiasis in addition to the treatment of oropharyngeal candidiasis. Posaconazole oral suspension solution has shown some limitations in the setting of fasting state absorption, elevated gastrointestinal pH, and increased motility. The newly approved delayed-release oral tablet and intravenous solution formulations provide additional treatment options by reducing interpatient variability and providing flexibility in these set of critically ill patients. This review will detail these most recent studies.

Fungal infections after liver transplantation: incidence and outcome

BACKGROUND

Fungal infections, although less frequent than bacterial infections, represent a severe comorbidity with an exponential increase in mortality rate in liver transplantation patients. The incidence of invasive fungal infections (IFIs) after solid organ transplantation ranges from 7% to 42%, with Candida spp. and Aspergillus spp. as the most common pathogens. Fungal infections in liver transplant recipients have been associated with poor outcome and mortality rates ranging from 65% to 90% for invasive aspergillosis and 30% to 50% for invasive candidiasis. The results largely depend on early diagnosis and early initiation of specific treatment for IFIs. Therefore, the diagnosis must be prompt, preferably based on microbiological data, both cultures and biomarkers, and/or based on clinical features and known risk factors.

MATERIALS AND METHODS

This study evaluated the incidence of fungal infections in patients after liver transplantation in our center between January 2003 and December 2012. The retrospective analysis of 215 consecutive liver transplantation patients was undertaken to estimate incidence, risk factors, and clinical courses of IFIs in the first 3 months after liver transplantation.

RESULTS

Candidemia and invasive candidiasis microbiologically proven were found in 26 patients (12%), whereas in 6 patients (2.8%) invasive fungal infections from other non-Candida fungi developed: Aspergillus (4 cases: 2 A fumigatus, 2 A terreus), Fusarium oxysporum (1 case), and Rhodotorula rubra (1 case). Two patients with Aspergillus and the patient with Fusarium died. The patient with Rhodotorula as well as 22 of the patients with candidemia (85%) survived. All of the episodes developed during the first 3 months posttransplantation. All cases have followed a previous polymicrobial bacterial infection (especially in the biliary tract) with large use of combined antibiotic therapies.

CONCLUSIONS

The rate of fungal infection was found to increase in parallel with the number of risk factors. Prophylactic strategies can decrease the risk of fungal infections. Early detection and treatment with adequate early empiric therapy is the key to obtaining a better outcome in liver transplantation patients.

Different Stress-Induced Calcium Signatures Are Reported by Aequorin-Mediated Calcium Measurements in Living Cells of Aspergillus fumigatus

Aspergillus fumigatus is an inhaled fungal pathogen of human lungs, the developmental growth of which is reliant upon Ca2+-mediated signalling. Ca2+ signalling has regulatory significance in all eukaryotic cells but how A. fumigatus uses intracellular Ca2+ signals to respond to stresses imposed by the mammalian lung is poorly understood. In this work, A. fumigatus strains derived from the clinical isolate CEA10, and a non-homologous recombination mutant ΔakuBKU80, were engineered to express the bioluminescent Ca2+-reporter aequorin. An aequorin-mediated method for routine Ca2+ measurements during the early stages of colony initiation was successfully developed and dynamic changes in cytosolic free calcium ([Ca2+]c) in response to extracellular stimuli were measured. The response to extracellular challenges (hypo- and hyper-osmotic shock, mechanical perturbation, high extracellular Ca2+, oxidative stress or exposure to human serum) that the fungus might be exposed to during infection, were analysed in living conidial germlings. The 'signatures' of the transient [Ca2+]c responses to extracellular stimuli were found to be dose- and age-dependent. Moreover, Ca2+-signatures associated with each physico-chemical treatment were found to be unique, suggesting the involvement of heterogeneous combinations of Ca2+-signalling components in each stress response. Concordant with the involvement of Ca2+-calmodulin complexes in these Ca2+-mediated responses, the calmodulin inhibitor trifluoperazine (TFP) induced changes in the Ca2+-signatures to all the challenges. The Ca2+-chelator BAPTA potently inhibited the initial responses to most stressors in accordance with a critical role for extracellular Ca2+ in initiating the stress responses.

Pleural effusion as the initial clinical presentation in disseminated cryptococcosis and fungaemia: an unusual manifestation and a literature review

BACKGROUND

Cryptococcus neoformans infection usually presents as chronic meningitis and is increasingly being recognized in immunocompromised patients. Presentation with pleural effusion is rare in cryptococcal disease; in fact, only 4 cases of pleural effusion as the initial clinical presentation in cryptococcosis have been reported in English-language literature to date. We report the first case of pleural effusion as the initial clinical presentation in a renal transplant recipient who was initially misdiagnosed with tuberculous pleuritis but who then developed fungaemia and disseminated cryptococcosis. The examination of this rare manifestation and the accompanying literature review will contribute to increased recognition of the disease and a reduction in misdiagnoses.

CASE PRESENTATION

We describe a 63-year-old male renal transplant recipient on an immunosuppressive regimen who was admitted for left pleural effusion and fever. Cytological examinations and pleural fluid culture were nonspecific and negative. Thoracoscopy only found chronic, nonspecific inflammation with fibrosis in the pleura. After empirical anti-tuberculous therapy, the patient developed an elevated temperature, a severe headache and vomiting and fainted in the ward. Cryptococci were specifically found in the cerebrospinal fluid following lumbar puncture. Blood cultures were twice positive for C. neoformans one week later. He was transferred to the respiratory intensive care unit (RICU) immediately and was placed on non-invasive ventilation for respiratory failure for 2 days. He developed meningoencephalitis and fungaemia with C. neoformans during hospitalization. He was given amphotericin B liposome combined with 5-flucytosine and voriconazole for first 11 days, then amphotericin B liposome combined with 5-flucytosine sustained to 8 weeks, after that changed to fluconazole for maintenance. His condition improved after antifungal treatment, non-invasive ventilation and other support. Further pathological consultation and periodic acid-Schiff staining revealed Cryptococcus organisms in pleural sections, providing reliable evidence for cryptococcal pleuritis.

CONCLUSION

Pleural effusion is an unusual manifestation of cryptococcosis. Cryptococcal infection must be considered in the case of patients on immunosuppressives, especially solid-organ transplant recipients, who present with pleural effusion, even if pleural fluid culture is negative. Close communication between the pathologist and the clinician, multiple special biopsy section stains and careful review are important and may contribute to decreasing misdiagnosis.

Pleural effusion as the initial clinical presentation in disseminated cryptococcosis and fungaemia: an unusual manifestation and a literature review

BACKGROUND

Cryptococcus neoformans infection usually presents as chronic meningitis and is increasingly being recognized in immunocompromised patients. Presentation with pleural effusion is rare in cryptococcal disease; in fact, only 4 cases of pleural effusion as the initial clinical presentation in cryptococcosis have been reported in English-language literature to date. We report the first case of pleural effusion as the initial clinical presentation in a renal transplant recipient who was initially misdiagnosed with tuberculous pleuritis but who then developed fungaemia and disseminated cryptococcosis. The examination of this rare manifestation and the accompanying literature review will contribute to increased recognition of the disease and a reduction in misdiagnoses.

CASE PRESENTATION

We describe a 63-year-old male renal transplant recipient on an immunosuppressive regimen who was admitted for left pleural effusion and fever. Cytological examinations and pleural fluid culture were nonspecific and negative. Thoracoscopy only found chronic, nonspecific inflammation with fibrosis in the pleura. After empirical anti-tuberculous therapy, the patient developed an elevated temperature, a severe headache and vomiting and fainted in the ward. Cryptococci were specifically found in the cerebrospinal fluid following lumbar puncture. Blood cultures were twice positive for C. neoformans one week later. He was transferred to the respiratory intensive care unit (RICU) immediately and was placed on non-invasive ventilation for respiratory failure for 2 days. He developed meningoencephalitis and fungaemia with C. neoformans during hospitalization. He was given amphotericin B liposome combined with 5-flucytosine and voriconazole for first 11 days, then amphotericin B liposome combined with 5-flucytosine sustained to 8 weeks, after that changed to fluconazole for maintenance. His condition improved after antifungal treatment, non-invasive ventilation and other support. Further pathological consultation and periodic acid-Schiff staining revealed Cryptococcus organisms in pleural sections, providing reliable evidence for cryptococcal pleuritis.

CONCLUSION

Pleural effusion is an unusual manifestation of cryptococcosis. Cryptococcal infection must be considered in the case of patients on immunosuppressives, especially solid-organ transplant recipients, who present with pleural effusion, even if pleural fluid culture is negative. Close communication between the pathologist and the clinician, multiple special biopsy section stains and careful review are important and may contribute to decreasing misdiagnosis.

Republished: The clinical spectrum of pulmonary aspergillosis

The clinical presentation of Aspergillus lung disease is determined by the interaction between fungus and host. Invasive aspergillosis develops in severely immunocompromised patients, including those with neutropenia, and increasingly in the non-neutropenic host, including lung transplant recipients, the critically ill patients and patients on steroids. A high index of suspicion is required in patients without the classical risk factors as early presentation is usually silent and non-specific, pyrexia uncommon and timely treatment is crucial for survival. Invasive aspergillosis has also been diagnosed in normal hosts after massive exposure to fungal spores. Chronic pulmonary aspergillosis affects patients without obvious immune compromise, but with an underlying lung condition such as COPD or sarcoidosis, prior or concurrent TB or non-tuberculous mycobacterial disease. Aspergillus bronchitis may be responsible for persistent respiratory symptoms in patients with Aspergillus detected repeatedly in sputum without evidence of parenchymal Aspergillus disease, especially in patients with bronchiectasis and cystic fibrosis. Allergic bronchopulmonary aspergillosis affects patients with asthma and cystic fibrosis, and is important to recognise as permanent lung or airways damage may accrue if untreated. Changes in the classification of Aspergillus allergic lung disease have been proposed recently. Cases of extrinsic allergic alveolitis and chronic pulmonary aspergillosis have been observed after Aspergillus exposure. Asymptomatic colonisation of the respiratory tract needs close monitoring as it can lead to clinical disease especially with ongoing immunosuppression. The various syndromes should be viewed as a semicontinuous spectrum of disease and one form may evolve into another depending on the degree of ongoing immunosuppression.

In silico modeling of spore inhalation reveals fungal persistence following low dose exposure

The human lung is constantly exposed to spores of the environmental mould Aspergillus fumigatus, a major opportunistic pathogen. The spectrum of resultant disease is the outcome of complex host-pathogen interactions, an integrated, quantitative understanding of which lies beyond the ethical and technical reach permitted by animal studies. Here we construct a mathematical model of spore inhalation and clearance by concerted actions of macrophages and neutrophils, and use it to derive a mechanistic understanding of pathogen clearance by the healthy, immunocompetent host. In particular, we investigated the impact of inoculum size upon outcomes of single-dose fungal exposure by simulated titrations of inoculation dose, from 10(6) to 10(2) spores. Simulated low-dose (10(2)) spore exposure, an everyday occurrence for humans, revealed a counter-intuitive prediction of fungal persistence (>3 days). The model predictions were reflected in the short-term dynamics of experimental murine exposure to fungal spores, thereby highlighting the potential of mathematical modelling for studying relevant behaviours in experimental models of fungal disease. Our model suggests that infectious outcomes can be highly dependent upon short-term dynamics of fungal exposure, which may govern occurrence of cyclic or persistent subclinical fungal colonisation of the lung following low dose spore inhalation in non-neutropenic hosts.

Diagnostic Modalities for Invasive Mould Infections among Hematopoietic Stem Cell Transplant and Solid Organ Recipients: Performance Characteristics and Practical Roles in the Clinic

The morbidity and mortality of hematopoietic stem cell and solid organ transplant patients with invasive fungal infections (IFIs) remain high despite an increase in the number of effective antifungal agents. Early diagnosis leading to timely administration of antifungal therapy has been linked to better outcomes. Unfortunately, the diagnosis of IFIs remains challenging. The current gold standard for diagnosis is a combination of histopathology and culture, for which the sensitivity is <50%. Over the past two decades, a plethora of non-culture-based antigen and molecular assays have been developed and clinically validated. In this article, we will review the performance of the current commercially available non-cultural diagnostics and discuss their practical roles in the clinic.

STAT1 signaling within macrophages is required for antifungal activity against Cryptococcus neoformans

Cryptococcus neoformans, the predominant etiological agent of cryptococcosis, is an opportunistic fungal pathogen that primarily affects AIDS patients and patients undergoing immunosuppressive therapy. In immunocompromised individuals, C. neoformans can lead to life-threatening meningoencephalitis. Studies using a virulent strain of C. neoformans engineered to produce gamma interferon (IFN-γ), denoted H99γ, demonstrated that protection against pulmonary C. neoformans infection is associated with the generation of a T helper 1 (Th1)-type immune response and signal transducer and activator of transcription 1 (STAT1)-mediated classical (M1) macrophage activation. However, the critical mechanism by which M1 macrophages mediate their anti-C. neoformans activity remains unknown. The current studies demonstrate that infection with C. neoformans strain H99γ in mice with macrophage-specific STAT1 ablation resulted in severely increased inflammation of the pulmonary tissue, a dysregulated Th1/Th2-type immune response, increased fungal burden, deficient M1 macrophage activation, and loss of protection. STAT1-deficient macrophages produced significantly less nitric oxide (NO) than STAT1-sufficient macrophages, correlating with an inability to control intracellular cryptococcal proliferation, even in the presence of reactive oxygen species (ROS). Furthermore, macrophages from inducible nitric oxide synthase knockout mice, which had intact ROS production, were deficient in anticryptococcal activity. These data indicate that STAT1 activation within macrophages is required for M1 macrophage activation and anti-C. neoformans activity via the production of NO.

Fatal Case of Probable Invasive Aspergillosis after Five Years of Heart Transplant: A Case Report and Review of the Literature

Invasive fungal infections are very common in solid organ transplants and occur most frequently in the first three months after transplant. A 49-year-old female with a history of two remote heart transplants with the most recent one occurring 5 years ago was admitted for increasing shortness of breath, cough, and fever. Computerized tomography (CT) scan of the chest showed left lower lung ground-glass and tree-in-bud opacities. She was started on broad spectrum antibiotics along with ganciclovir and micafungin. Ganciclovir was added due to the patient's past history of CMV infection and empiric fungal coverage with micafungin. Bronchoalveolar lavage (BAL) was performed as her respiratory status worsened and voriconazole was added for possible aspergillosis in combination therapy with micafungin. BAL galactomannan returned positive which was suggestive of aspergillosis. Patient worsened clinically and subsequently succumbed to cardiorespiratory arrest despite our best efforts. It is important to have a high degree of clinical suspicion for invasive aspergillosis in transplant patients even many years after transplant and initiate aggressive therapy due to poor outcomes.

Impact of abdominal drainage systems on postoperative complication rates following liver transplantation

BACKGROUND

Depending on the extent of surgery, coagulation status and the number of anastomoses, drains are routinely used during liver transplantation. The aim of this study was to compare different drain types with regard to abdominal complication rates.

METHODS

All consecutive full-size orthotopic liver transplantations (LTX) performed over a 7-year period were included in this retrospective analysis. Abdominal drain groups were divided into open-circuit drains and closed-circuit drains. Data are reported as total number (%) or median (range); for all comparisons a p value <0.05 was considered statistically significant.

RESULTS

A total of 256 LTX [age 56.89 (0.30-75.21) years; MELD 14.5 (7-40)] was included; 56 (21.8 %) patients received an open-circuit Easy Flow Drain (Group 1) and 200 (78.2 %) a closed-circuit Robinson Drainage System (Group 2). For Groups 1 and 2, overall infection rates were 78.6 and 56 % (p = 0.001), abdominal infection rates 50.82 and 21.92 % (p = 0.001), yeast infection rates 37 and 23 % (p = 0.02), abdominal bleeding rates 26.78 and 17 % (p = 0.07), biliary complication rates 14.28 and 13.5 % (p = 0.51), respectively.

CONCLUSIONS

In this retrospective series, open-circuit drains were associated with more abdominal complications, mainly due to intraabdominal infections, than were closed-circuit drains.

The Impact of Opportunistic Infections on Clinical Outcome and Healthcare Resource Uses for Adult T Cell Leukaemia

We examined the impact of opportunistic infections on in-hospital mortality, hospital length of stay (LOS), and the total cost (TC) among adult T-cell leukaemia (ATL) patients. In this retrospective cohort study, we identified 3712 patients with ATL using national hospital administrative data. Analysed opportunistic infections included Aspergillus spp., Candida spp., cytomegalovirus (CMV), herpes simplex virus (HSV), pneumocystis pneumonia (PCP), tuberculosis, varicella zoster virus (VZV), Cryptococcus spp., nontuberculous mycobacteria, and Strongyloides spp. Multilevel logistic regression analysis for in-hospital mortality and a multilevel linear regression analysis for LOS and TC were employed to determine the impact of opportunistic infections on clinical outcomes and healthcare resources. We found ATL patients infected with CMV had significantly higher in-hospital mortality (adjusted odds ratio (AOR) 2.29 [1.50-3.49] p < 0.001), longer LOS (coefficient (B): 0.13 [0.06-0.20] p < 0.001) and higher TC (B: 0.25 [0.17-0.32] p < 0.001) than those without CMV. Those with CAN and PCP were associated with a lower in-hospital mortality rate (AOR 0.72 [0.53-0.98] p = 0.035 and 0.54[0.41-0.73] p < 0.001, respectively) than their infections. VZV was associated with longer LOS (B: 0.13 [0.06-0.19] p < 0.001), while aspergillosis, HSV, or VZV infections were associated with higher TC (B: 0.16 [0.07-0.24] p < 0.001, 0.12 [0.02-0.23] p = 0.025, and 0.17 [0.10-0.24] p < 0.001, respectively). Our findings reveal that CMV infection is a major determinant of poor prognosis in patients affected by ATL.

Comparing Etest and Broth Microdilution for Antifungal Susceptibility Testing of the Most-Relevant Pathogenic Molds

Invasive mold infections are life-threatening diseases for which appropriate antifungal therapy is crucial. Their epidemiology is evolving, with the emergence of triazole-resistant Aspergillus spp. and multidrug-resistant non-Aspergillus molds. Despite the lack of interpretive criteria, antifungal susceptibility testing of molds may be useful in guiding antifungal therapy. The standard broth microdilution method (BMD) is demanding and requires expertise. We assessed the performance of a commercialized gradient diffusion method (Etest method) as an alternative to BMD. The MICs or minimal effective concentrations (MECs) of amphotericin B, voriconazole, posaconazole, caspofungin, and micafungin were assessed for 290 clinical isolates of the most representative pathogenic molds (154 Aspergillus and 136 non-Aspergillus isolates) with the BMD and Etest methods. Essential agreements (EAs) within ±2 dilutions of ≥90% between the two methods were considered acceptable. EAs for amphotericin B and voriconazole were >90% for most potentially susceptible species. For posaconazole, the correlation was acceptable for Mucoromycotina but Etest MIC values were consistently lower for Aspergillus spp. (EAs of <90%). Excellent EAs were found for echinocandins with highly susceptible (MECs of <0.015 μg/ml) or intrinsically resistant (MECs of >16 μg/ml) strains. However, MEC determinations lacked consistency between methods for strains exhibiting mid-range MECs for echinocandins. We concluded that the Etest method is an appropriate alternative to BMD for antifungal susceptibility testing of molds under specific circumstances, including testing with amphotericin B or triazoles for non-Aspergillus molds (Mucoromycotina and Fusarium spp.). Additional study of molecularly characterized triazole-resistant Aspergillus isolates is required to confirm the ability of the Etest method to detect voriconazole and posaconazole resistance among Aspergillus spp.

An Approach to a Pulmonary Infiltrate in Solid Organ Transplant Recipients

The onset of a pulmonary infiltrate in a solid organ transplant (SOT) recipient is both a challenging diagnostic and therapeutic challenge. We outline the potential aetiologies of a pulmonary infiltrate in a SOT recipient, with particular attention paid to fungal pathogens. A diagnostic and empirical therapy approach to a pulmonary infiltrate, especially invasive fungal disease (IFD) in SOT recipients, is provided.

The Screening Performance of Serum 1,3-Beta-D-Glucan in Patients with Invasive Fungal Diseases: A Meta-Analysis of Prospective Cohort Studies

The serum 1,3-beta-D-glucan (BG) assay aids in the early diagnosis of invasive fungal diseases (IFDs) and has been approved for their diagnosis. However, reports on the screening performance of BG are scarce. We performed a meta-analysis of data extracted from only prospective cohort studies to evaluate the screening performance of the BG assay in the diagnosis of IFDs. We specifically searched 4 databases (the PubMed, Web of Science, Elsevier, and Cochrane Collaboration databases) according to EORTC-MSG criteria. A total of 1068 patients in 11 studies were analyzed. Deeks’ funnel plot asymmetry test suggested a low likelihood of publication bias for the included studies (p = 0.055). The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curve, with 95% confidence intervals, were 0.75(0.63,0.84), 0.87(0.81,0.92), 5.85(3.96,8.63), 0.30(0.20,0.45), 19.53(11.16,34.18), and 0.89(0.86,0.91), respectively. The findings of this meta-analysis suggest that the BG assay is a useful screening tool with high sensitivity and specificity for discriminating between patients with and without IFDs. In clinical practice, BG assay results should be evaluated together with clinical and microbiological findings.

Invasive Fusariosis in the Voriconazole Era: Single-Center 13-Year Experience

Invasive fusariosis is an aggressive fungal disease among immunocompromised patients. Mortality remains high in the voriconazole era. Combination therapy should be studied systematically for fusariosis.

Background. Invasive fusariosis remains an aggressive, albeit infrequent infection in immunocompromised patients.

Methods. We identified all cases of invasive fusariosis between January 2002 and December 2014. We recorded patient characteristics including clinical presentation, treatment, and outcomes at 6 and 12 weeks after diagnosis, as well as species identification and antifungal drug susceptibilities.

Results. Fifteen patients were diagnosed with proven (12, 80%) or probable (3, 20%) fusariosis. Median age was 60 years (range, 26–78), and 10 patients were male. Underlying conditions included hematological malignancies (13, 87%), juvenile idiopathic arthritis (1, 7%), and third-degree burns (1, 7%). Five patients underwent hematopoietic stem-cell transplantation before diagnosis. Six patients (40%) received systemic glucocorticoids, and 11 patients (73%) had prolonged neutropenia at the time of diagnosis. Clinical presentations included the following: skin/soft tissue infection (8, 53%), febrile neutropenia (4, 27%), respiratory tract infection (2, 13%), and septic arthritis (1, 7%). Twelve patients were treated with voriconazole: 6 (40%) with voriconazole alone, 4 (27%) with voriconazole and terbinafine, and 2 (13%) with voriconazole, terbinafine, and amphotericin. One patient (7%) was treated with terbinafine alone, and another with micafungin alone. Four patients underwent surgical debridement (4, 27%). Susceptibility testing was performed on 9 isolates; 8 demonstrated voriconazole minimum inhibitory concentrations ≥4 µg/mL. The cumulative probability of survival was 66.7% and 53.3% at 6 and 12 weeks after diagnosis.

Conclusions. Mortality associated with invasive fusariosis remains high. Cumulative mortality at our center was lower than previous reports despite elevated voriconazole minimum inhibitory concentrations. Combination therapy should be studied systematically for fusariosis.

Histoplasmosis and Blastomycosis in Solid Organ Transplant Recipients

Histoplasmosis and blastomycosis are geographically restricted dimorphic fungi that cause infection after the conidia produced in the mold phase are inhaled into the lungs. In the lungs, at 37 °C, these organisms undergo transformation into the yeast phase. In transplant recipients, infection can occur by exposure to the mold in the environment, by reactivation of infection that had occurred previously and had been controlled by the host until immunosuppressive medications were given post-transplantation, and finally by transmission from the donor organ in the case of histoplasmosis. In transplant recipients, disseminated infection is common, and pulmonary infection is more likely to be severe than in a non-immunosuppressed person. Diagnosis has been improved, allowing earlier treatment, with the use of rapid antigen tests performed on serum and urine. Initial treatment, for all but the mildest cases of acute pulmonary histoplasmosis, should be with a lipid formulation of amphotericin B. After clinical improvement has occurred, step-down therapy with itraconazole is recommended for a total of 12 months for most transplant recipients, but some patients will require long-term suppressive therapy to prevent relapse of disease.