Combination of Voriconazole and Caspofungin as Primary Therapy for Invasive Aspergillosis in Solid Organ Transplant Recipients: A Prospective, Multicenter, Observational Study

Invasive mould sinusitis in patients with haematological malignancies: a 10 year single-centre study

OBJECTIVES

Invasive mould sinusitis (IMS) is a severe infection in patients with haematological malignancies. Because of a paucity of contemporaneous data about IMS, we sought to evaluate clinical aspects and outcome of IMS in these patients.

METHODS

The records of adult haematological malignancy patients with proven or probable IMS over a 10 year period were reviewed retrospectively.

RESULTS

We identified 44 patients with IMS. Mucorales were isolated in 13 (35.1%) patients and Fusarium and Aspergillus were isolated in 9 (24.3%) patients each. Patients with IMS owing to Mucorales were more likely to have a history of diabetes mellitus (P = 0.003) and high-dose corticosteroid use (P = 0.03). Thirty-five (80%) patients received antifungal combinations and 36 (82%) underwent surgical debridement. The 12 week IMS-attributable mortality was 36.4% (16 patients). A relapsed and/or refractory haematological malignancy was an independent risk factor for 6 week IMS-attributable (P = 0.038), 12 week all-cause (P = 0.005) and 12 week IMS-attributable (P = 0.0015) mortality. Neutrophil count <100/µL and lymphocyte count <200/µL were associated with increased 12 week IMS-attributable and 6 week all-cause mortality, respectively (P = 0.044 and 0.013). IMS due to Aspergillus was an independent risk factor for both 12 week all-cause (P = 0.011) and IMS-attributable (P = 0.026) mortality. Initial antifungal therapy with a triazole-containing regimen was associated with decreased 6 week all-cause (P = 0.032) and IMS-attributable (P = 0.038) mortality. Surgery was not an independent factor for improved outcome.

CONCLUSIONS

Despite combined medical and surgical therapy, IMS had high mortality. Mortality risk factors were relapsed and/or refractory malignancy, cytopenia and Aspergillus infection in this study.

Lung transplantation for cystic fibrosis: results, indications, complications, and controversies

Survival in patients with cystic fibrosis (CF) has improved dramatically over the past 30 to 40 years, with mean survival now approximately 40 years. Nonetheless, progressive respiratory insufficiency remains the major cause of mortality in CF patients, and lung transplantation (LT) is eventually required. Timing of listing for LT is critical, because up to 25 to 41% of CF patients have died while awaiting LT. Globally, approximately 16.4% of lung transplants are performed in adults with CF. Survival rates for LT recipients with CF are superior to other indications, yet LT is associated with substantial morbidity and mortality (∼50% at 5-year survival rates). Myriad complications of LT include allograft failure (acute or chronic), opportunistic infections, and complications of chronic immunosuppressive medications (including malignancy). Determining which patients are candidates for LT is difficult, and survival benefit remains uncertain. In this review, we discuss when LT should be considered, criteria for identifying candidates, contraindications to LT, results post-LT, and specific complications that may be associated with LT. Infectious complications that may complicate CF (particularly Burkholderia cepacia spp., opportunistic fungi, and nontuberculous mycobacteria) are discussed.

Invasive aspergillosis in liver transplant recipients: epidemiology, clinical characteristics, treatment, and outcomes in 116 cases

Invasive aspergillosis (IA) in liver transplant recipients is associated with grave outcomes. We reviewed 116 individual cases reported in the literature from 1985 to 2013. IA was diagnosed after a median of 25 days after transplantation and involved a single organ in 51% of the cases, whereas in the remaining cases, multiple sites were involved. The most common infecting Aspergillus species were Aspergillus fumigatus (73%), Aspergillus flavus (14%), and Aspergillus terreus (8%). Amphotericin B was the drug most frequently used, and it was followed by voriconazole and itraconazole. Combination regimens were used in 51% of the cases. The overall 1-year cumulative survival probability was 35% [95% confidence interval (CI) = 24.6%-49.6%]. Survival was significantly higher for patients reported from the year 2000 and thereafter (P < 0.001), for those diagnosed with IA more than 30 days after transplantation versus those diagnosed earlier (P = 0.019), and for patients without renal failure (P = 0.020). Additionally, the use of voriconazole was significantly associated with a higher probability of survival (P < 0.001). Cox regression analysis showed that subjects with the involvement of multiple sites had a 2.52 times higher risk of a negative outcome (95% CI = 1.08-5.87) than those with the involvement of a single site. Thus, IA causes life-threatening infections in liver transplant recipients. Predictors associated with poor outcomes may help clinicians to optimize the management of this infection.

Combination antifungal therapy for invasive aspergillosis: a randomized trial

BACKGROUND

Invasive aspergillosis (IA) is associated with poor outcomes in patients with hematologic malignancies (HMs) and hematopoietic cell transplantation (HCT). Small studies suggest a role for combination antifungal therapy.

OBJECTIVE

To assess the safety and efficacy of voriconazole and anidulafungin compared with voriconazole monotherapy for treatment of IA.

DESIGN

Randomized, double-blind, placebo-controlled multicenter trial. (ClinicalTrials.gov: NCT00531479).

SETTING

93 international sites.

PATIENTS

454 patients with HM or HCT and suspected or documented IA were randomly assigned to treatment with voriconazole and anidulafungin or placebo. Primary analysis was done in the modified intention-to-treat population of 277 patients in whom IA was confirmed.

MEASUREMENTS

The primary outcome was 6-week mortality; secondary outcomes included 12-week mortality, mortality in major subgroups, and safety measures.

RESULTS

Mortality rates at 6 weeks were 19.3% (26 of 135) for combination therapy and 27.5% (39 of 142) for monotherapy (difference, -8.2 percentage points [95% CI, -19.0 to 1.5]; P  = 0.087). Secondary mortality outcomes favored combination therapy. Multivariable regression analysis suggested that maximum galactomannan value, Karnofsky score, and baseline platelet count had prognostic significance. Most patients (218 of 277 [78.7%]) had IA diagnosis established by radiographic findings and maximum galactomannan positivity. In a post hoc analysis of this dominant subgroup, 6-week mortality was lower in combination therapy than monotherapy (15.7% [17 of 108] vs. 27.3% [30 of 110]; difference, -11.5 percentage points [CI, -22.7 to -0.4]; P = 0.037). Safety measures, including hepatotoxicity, were not different.

LIMITATIONS

Mortality at 6 weeks was higher than expected, and the difference in mortality was lower than expected, which reduced power to detect a treatment effect. Enrollment was restricted to patients with HM or HCT, which limited generalizability.

CONCLUSION

Compared with voriconazole monotherapy, combination therapy with anidulafungin led to higher survival in subgroups of patients with IA. Limitations in power preclude definitive conclusions about superiority.

PRIMARY FUNDING SOURCE

Pfizer.

Clinical experience of the use of voriconazole, caspofungin or the combination in primary and salvage therapy of invasive aspergillosis in haematological malignancies

Invasive aspergillosis (IA) is a life-threatening infection in severely immunocompromised haematological malignancy patients. In this study, the efficacy and safety of caspofungin, voriconazole or the combination as primary and salvage therapy in patients with IA were compared. The study included 181 patients with haematological malignancies and IA who received primary or salvage therapy with caspofungin, voriconazole or the combination. In total, 138 patients who received treatment for ≥7 days were analysed; 86 underwent primary antifungal therapy (15 with caspofungin, 38 with voriconazole and 33 with both). Among the salvage therapy patients, 17 received caspofungin, 24 received voriconazole and 35 received both. In the primary therapy group, no difference in therapy response was found, but caspofungin was associated with higher IA mortality rates. A multivariate competing risk analysis of primary antifungal therapy revealed that voriconazole was independently associated with lower IA-associated mortality rates than caspofungin (hazard ratio=0.2, 95% confidence interval 0.06-0.96; P=0.04). In the salvage therapy group, the three treatment groups had similar responses and IA-associated mortality rates. The combination of voriconazole and caspofungin did not result in better outcomes compared with voriconazole alone, as primary or salvage therapy, in haematological malignancy patients. However, voriconazole was associated with a lower Aspergillus-associated mortality rate compared with caspofungin monotherapy.

Salvage combination antifungal therapy for acute invasive aspergillosis may improve outcomes: a systematic review and meta-analysis

OBJECTIVE

A meta-analysis was performed to compare mold-active triazoles or lipid amphotericin B plus an echinocandin to non-echinocandin monotherapy for acute invasive aspergillosis (IA).

METHODS

We searched PubMed, EMBASE, and other databases through May 2013 unrestricted by language. We included observational and experimental studies wherein patients with proven or probable IA by EORTC/MSG criteria underwent our comparative intervention. PRISMA and MOOSE guidelines were followed and quality was assessed using the Jadad and Newcastle-Ottawa criteria. Meta-regression with fixed and random effects and sensitivity analyses were performed. The primary study outcome measure was 12-week overall mortality. The secondary outcome assessed was complete and partial response.

RESULTS

Only observational studies of primary 12-week survival showed heterogeneity (I(2)=48.96%, p=0.05). For salvage IA therapy, fixed effects models demonstrated improved 12-week survival (Peto odds ratio (OR) 1.80, 95% confidence interval (CI) 1.08-3.01) and success (Peto OR 2.17, 95% CI 1.21-3.91) of combination therapy. Significance remained after applying random effects as a sensitivity analysis (12-week survival: Peto OR 1.90, 95% CI 1.04-3.46, and unchanged value for success). Restriction to high quality studies and including echinocandins as the comparator for refractory IA revealed an adjusted OR of 1.72 (95% CI 0.96-3.09; p=0.07) for global success, while the survival endpoint remained unaltered.

CONCLUSIONS

Combination antifungals for IA demonstrate improved outcomes over monotherapy in the salvage setting. Clinicians should consider this approach in certain situations.

[Mold infections in lung transplants]

Invasive infections by molds, mainly Aspergillus infections, account for more than 10% of infectious complications in lung transplant recipients. These infections have a bimodal presentation: an early one, mainly invading bronchial airways, and a late one, mostly focused on lung or disseminated. The Aspergillus colonization at any time in the post-transplant period is one of the major risk factors. Late colonization, together with chronic rejection, is one of the main causes of late invasive forms. A galactomannan value of 0.5 in bronchoalveolar lavage is currently considered a predictive factor of pulmonary invasive infection. There is no universal strategy in terms of prophylaxis. Targeted prophylaxis and preemptive treatment instead of universal prophylaxis, are gaining more followers. The therapeutic drug monitoring level of azoles is highly recommended in the treatment. Monotherapy with voriconazole is the treatment of choice in invasive aspergillosis; combined antifungal therapies are only recommended in severe, disseminated, and other infections due to non-Aspergillus molds.

A long-term survivor of disseminated Aspergillus and mucorales infection: an instructive case

Invasive fungal infections remain major causes of infection-related mortality in hematopoietic stem cell transplantation (HSCT) patients. Mixed infections and multiple organ involvement have been reported in these patients. Here, we report a case of mixed Aspergillus and Mucorales infection involving the lungs, brain, spleen and bone in a HSCT patient with relapsed acute myeloid leukemia, who finally improved with triple antifungal therapy and neurosurgical evacuation of brain abscesses. She was put on lifelong secondary prophylaxis with posaconazole with excellent compliance and no sign of toxicity despite over 10 years of drug administration. Serial galactomannan measurements and positron emission tomography/computed tomography were used and were helpful for disease activity monitoring. This is an instructive case of long-term survival after a severe combined mould infection.

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.

Current and future therapies for invasive aspergillosis

Invasive fungal infections have increase worldwide and represent a threat for immunocompromised patients including HIV-infected, recipients of solid organ and stem cell transplants, and patients receiving immunosuppressive therapies. High mortality rates and difficulties in early diagnosis characterize pulmonary fungal infections. Invasive pulmonary aspergillosis has been reviewed focussing on therapeutic management. Although new compounds have become available in the past years (i.e., amphotericin B lipid formulations, last-generation azoles, and echinocandines), new diagnostic tools and careful therapeutic management are mandatory to assure an early appropriate targeted treatment that represents the key factor for a successful conservative approach in respiratory fungal infections.

Efficacy of combination therapy of triazole and echinocandin in treatment of invasive aspergillosis: a systematic review of animal and human studies

OBJECTIVE

The effectiveness of the combination therapy of triazole and echinocandin in treatment of invasive aspergillosis (IA) remains controversial. The objective of this systematic review was to assess the efficacy of combination therapy of triazole and echinocandin in treatment of IA.

METHODS

Relevant articles on the combination therapy of triazole and echinocandin in IA, including the animal studies and clinical studies from January 1966 to October 2013, were searched on Web of Science, PubMed and Cochrane Library. The prolongation of survival of the combination therapy of triazole and echinocandin in IA was performed as risk ratio (RR) with 95% confidence interval (95% CI).

RESULTS

Nine animal studies with a total of 1,582 animals and five clinical trials totaling 872 patients were included. The survival of the included animal studies with combination therapy was significantly prolonged compared with echinocandin alone [RR =2.26, (95% CI, 1.79-2.87; P<0.00001)], but no statistical difference compared with monotherapy of triazole [RR =1.19, (95% CI, 0.98-1.44; P=0.08)]. Of the four human cohort studies, two studies observed that the combination therapy of triazole and echinocandin was associated with a significant reduction in mortality compared with other treatments, and one study might be considered as a preferable therapy [HR =0.58, (95% CI, 0.3-1.14; P=0.117)]. While another study revealed that there was no significant difference among the combination therapy of triazole and echinocandin and either of the monotherapy. In the randomized clinical trial (RCT), of the 135 patients who received the combination therapy, 39 died, while 55 died out of 142 patients who received monotherapy (P=0.08, 95% CI, -21.4, 1.09) by week 12.

CONCLUSIONS

The combination therapy of triazole and echinocandin in treating IA results in a trend towards improved overall survival in animals' studies and clinical studies. Well-designed RCTs and further improved clinical trials are necessary to study the effectiveness of the combination therapy.

Pseudomembranous Aspergillus tracheobronchitis: a potential for high mortality in low-risk patients

Pseudomembranous Aspergillus tracheobronchitis (PMATB) is a relatively uncommon form of invasive pulmonary aspergillosis. PMATB is characterized by necrosis and sloughing of the respiratory epithelium resulting from the invasion of the tracheobronchial mucosa by Aspergillus species. The prognosis for patients with PMATB and underlying immune compromise is poor, but existing data suggest that the outcome of PMATB occurring in patients without overt immune compromise is favorable. To investigate the clinical features and prognosis for immunocompetent patients with PMATB in the study center, 10 patients with histologically and microbiologically confirmed PMATB lacking overt immune compromise over a 9-year period were retrospectively identified. Although all patients ultimately received systemic antifungal therapy, 4 patients required mechanical ventilation and 3 patients died. This report indicates that PMATB occurring in immunocompetent patients may exhibit an aggressive course, with rapid progression of lung parenchymal involvement and a fatal outcome.

Fungal infections in cancer patients

Invasive fungal infections (IFI) have become a leading cause of morbidity and mortality in cancer patients. Infections with these organisms are often difficult to diagnose and treat. Appropriate and timely diagnosis requires a high index of suspicion and invasive procedures, including biopsy, to confirm the diagnosis. Treatment may be difficult, secondary to variable susceptibility and difficulty with exact and specific characterization of the fungal pathogen. The pathogens that are seen range from yeasts to invasive molds. Fortunately newer, noninvasive diagnostic techniques are available to aid in the diagnosis and treatments have become better tolerated and more efficacious.

Efficacy of the combination of voriconazole and caspofungin in experimental pulmonary aspergillosis by different Aspergillus species

Objectives

Invasive pulmonary aspergillosis (IPA) caused by Aspergillus fumigatus, Aspergillus flavus, or Aspergillus niger is associated with high mortality. We evaluated the efficacy and compared the therapeutic effect differences of voriconazole (VRC) in combination with caspofungin (CAS) in transiently neutropenic rats infected by A. fumigatus, A. flavus, or A. niger.

Methods

Treatment groups consisted of VRC (10 mg/kg q12 h) monotherapy, CAS (1 mg/kg/day) monotherapy, combination of VRC (10 mg/kg q12 h) + CAS (1 mg/kg/day), and no drug for 10 consecutive days. The efficacy and the difference in the treatments were evaluated through prolongation of survival, reduction in serum galactomannan levels and residual fungal burden, and histological studies.

Results

For all the strains, the combination of VRC and CAS led to significant prolongation in survival (P < 0.05) and reduction in residual fungal burden (P < 0.05) compared with CAS alone, and decrease in serum galactomannan levels (P < 0.05) compared with either agent alone. The survival in the combined therapy groups was significantly improved compared to VRC monotherapy for the strains of A. flavus and A. niger (P < 0.05), but no significant difference for the strains of A. fumigatus (P > 0.05).

Conclusions

Combination of VRC and CAS was synergistic in IPA by A. flavus and A. niger, but small efficacy benefits in IPA by A. fumigatus.

Impact of in vivo triazole and echinocandin combination therapy for invasive pulmonary aspergillosis: enhanced efficacy against Cyp51 mutant isolates

Previous studies examining combination therapy for invasive pulmonary aspergillosis (IPA) have revealed conflicting results, including antagonism, indifference, and enhanced effects. The most commonly employed combination for this infection includes a mold-active triazole and echinocandin. Few studies have evaluated combination therapy from a pharmacodynamic (PD) perspective, and even fewer have examined combination therapy against both wild-type and azole-resistant Cyp51 mutant isolates. The current studies aim to fill this gap in knowledge. Four Aspergillus fumigatus isolates were utilized, including a wild-type strain, an Fks1 mutant (posaconazole susceptible and caspofungin resistant), and two Cyp51 mutants (posaconazole resistant). A neutropenic murine model of IPA was used for the treatment studies. The dosing design included monotherapy with posaconazole, monotherapy with caspofungin, and combination therapy with both. Efficacy was determined using quantitative PCR, and results were normalized to known quantities of conidia (conidial equivalents [CE]). The static dose, 1-log kill dose, and associated PD target area under the curve (AUC)/MIC ratio were determined for monotherapy and combination therapy. Monotherapy experiments revealed potent activity for posaconazole, with reductions of 3 to 4 log10 Aspergillus CE/ml with the two "low"-MIC isolates. Posaconazole alone was less effective for the two isolates with higher MICs. Caspofungin monotherapy did not produce a significant decrease in fungal burden for any strain. Combination therapy with the two antifungals did not enhance efficacy for the two posaconazole-susceptible isolates. However, the drug combination produced synergistic activity against both posaconazole-resistant isolates. Specifically, the combination resulted in a 1- to 2-log10 decline in burden that would not have been predicted based on the monotherapy results for each drug. This corresponded to a reduction in the free-drug posaconazole AUC/MIC ratio needed for stasis of up to 17-fold. The data suggest that combination therapy using a triazole and an echinocandin may be a beneficial treatment strategy for triazole-resistant isolates.

Aspergillus tracheobronchitis causing subtotal tracheal stenosis in a liver transplant recipient

Invasive aspergillosis is recognized as one of the most significant opportunistic infections after liver transplantation. Diagnosis of invasive aspergillosis in transplant recipients has been proven to be challenging, and optimal approach to the treatment of invasive aspergillosis is still controversial. We here present an unusual case of Aspergillus tracheobronchitis in the setting of liver transplantation. A 47-year-old female patient with persistent dry cough after liver transplantation developed respiratory insufficiency and was readmitted to the intensive care unit 55 days after liver transplantation. A CT scan revealed subtotal tracheal stenosis; bronchoscopy was performed, and extended white mucus coverings causative of the tracheal stenosis were removed. Microbiological assessment isolated Aspergillus fumigatus. The diagnosis was obstructive Aspergillus tracheobronchitis. The patient was started on a treatment of voriconazole 200 mg orally twice daily, adjusted to a trough level of 1-4 mg/L. For further airway management, a tracheal stent had to be implanted. The patient is alive and well 28 months after liver transplantation. Invasive aspergillosis should be considered a possible etiology in liver transplant patients presenting with unspecific symptoms such as persistent dry cough. Optimal strategies for improved and early diagnosis as well as prophylaxis need to be defined.

[Antifungal treatment options in the critically ill patient]

Invasive fungal infections, especially in the critical care setting, have become an excellent target for prophylactic, empiric, and pre-emptive therapy interventions due to their associated high morbidity, mortality rate, increased incidence, and healthcare costs. For these reasons, new studies and laboratory tests have been developed over the last few years in order to formulate an early therapeutic intervention strategy in an attempt to reduce the high mortality rate associated with these infections. In recent years, evidence-based studies have shown the roles that the new antifungal drugs play in the treatment of invasive mycosis in seriously ill and complex patients, although data from critically ill patients are more limited. New antifungal agents have been analyzed in different clinical situations in critical care units, and the increasing number of non-Candida albicans species suggest that the application of early echinocandin therapy in critically ill patients with invasive candidiasis is a good option. Voriconazole should be recommended for invasive aspergillosis as a first line option.

[Pulmonary aspergillosis in a non-immunocompromised critically ill patient]

BACKGROUND

In non-immunocompromised patients admitted to intensive care departments or units (ICU), it is difficult to establish a definitive diagnosis of pulmonary aspergillosis because the signs and symptoms of this infectious disease are non-specific, and serological techniques are not very specific as well. For this reason, a diagnosis of possible pulmonary aspergillosis is initially established, and the starting of the treatment is controversial.

CASE REPORT

An immunocompetent subject had a work-related accident after a fall, which resulted in multiple injuries (head, thorax, lower extremities). The patient required mechanical ventilation since admission. On the second week of ICU admission, he showed a clinical presentation of respiratory infection with fever, purulent secretions, bilateral pulmonary infiltrates and repeated isolation of Mucor and Aspergillus fumigatus in bronchial secretions and pharyngeal swabs. The patient was treated with amphotericin B lipid complex and voriconazole with an excellent clinical and radiological outcome.

CONCLUSIONS

Combined treatment of antifungal agents, in this case amphotericin B lipid complex and voriconazole, is a therapeutic possibility to be considered in patients who failed to respond to initial antifungal monotherapy.

Invasive candidiasis: update on current pharmacotherapy options and future perspectives

INTRODUCTION

Invasive candidiasis (IC), mainly candidemia, is a leading cause of morbidity and mortality among immunocompromised patients and those admitted to intensive care units. Despite the recognition of risk factors and advances in disease prevention, Candida-related hospitalizations and mortality continue to rise. For treatment, four classes of older and newer antifungal agents are currently available. Adjunctive immunotherapies and a monoclonal antibody against heat shock protein 90 (efungumab) are promising novel therapeutic approaches.

AREAS COVERED

In this article, approaches and therapeutic agents for candidemia and other forms of IC are reviewed.

EXPERT OPINION

The thorough understanding of the available antifungal agents in combination with the increasing knowledge of the mechanisms that underlie the pathogenesis of Candida infections and the development of newer approaches such as efungumab and immunotherapy with adjunctive cytokines may improve the prognosis of patients with life-threatening invasive Candida infections.

Fungal infection in solid organ recipients

In solid organ recipients, as with other immunosuppressed patients, infections by Candida spp. and Aspergillus spp. are the most frequent invasive mycoses. Infections by Cryptococcus spp. and fungi of the Mucorales order are less common. Infections by Fusarium spp. and Scedosporium spp. are very uncommon, except in patients undergoing hematopoietic stem cell transplant and patients with prolonged neutropenia. The risk factors for fungal infection are immunosuppression, surgery, viral co-infection, and environmental exposure. Diagnosis is challenging: blood culture is of little use, except in candidiasis and cryptococcosis, and the poor accuracy of antigen-based techniques, except in cryptococcosis, favors widespread use of empirical therapy. A delay in the initiation of therapy increases the already high mortality of these infections. The agents used to treat fungal infection are azoles, echinocandins, and lipid amphotericin. Administration depends on antifungal activity, drug-drug interactions with calcineurin inhibitors, and safety profiles (effects on grafts and other side effects).

Invasive fungal infections in solid organ transplant recipients

Invasive fungal infections are a major problem in solid organ transplant (SOT) recipients. Overall, the most common fungal infection in SOT is candidiasis, followed by aspergillosis and cryptococcosis, except in lung transplant recipients, where aspergillosis is most common. Development of invasive disease hinges on the interplay between host factors (e.g., integrity of anatomical barriers, innate and acquired immunity) and fungal factors (e.g., exposure, virulence and resistance to prophylaxis). In this article, we describe the epidemiology and clinical features of the most common fungal infections in organ transplantation. Within this context, we review recent advances in diagnostic modalities and antifungal chemotherapy, and their impact on evolving prophylaxis and treatment paradigms.

Combination of voriconazole and anidulafungin for treatment of triazole-resistant aspergillus fumigatus in an in vitro model of invasive pulmonary aspergillosis

Voriconazole is a first-line agent for the treatment of invasive pulmonary aspergillosis. Isolates with elevated voriconazole MICs are increasingly being seen, and the optimal treatment regimen is not defined. We investigated whether the combination of voriconazole with anidulafungin may be beneficial for the treatment of A. fumigatus strains with elevated voriconazole MICs. We used an in vitro model of the human alveolus to define the exposure-response relationships for a wild-type strain (voriconazole MIC, 0.5 mg/liter) and strains with defined molecular mechanisms of triazole resistance (MICs, 4 to 16 mg/liter). All strains had anidulafungin minimum effective concentrations (MECs) of 0.0078 mg/liter. Exposure-response relationships were estimated using galactomannan as a biomarker. Concentrations of voriconazole and anidulafungin were measured using high-performance liquid chromatography (HPLC). The interaction of voriconazole and anidulafungin was described using the Greco model. Fungal growth was progressively inhibited with higher drug exposures of voriconazole. Strains with elevated voriconazole MICs required proportionally greater voriconazole exposures to achieve a comparable antifungal effect. Galactomannan concentrations were only marginally reduced by anidulafungin monotherapy. An additive effect between voriconazole and anidulafungin was apparent. In conclusion, the addition of anidulafungin does not markedly alter the exposure-response relationship of voriconazole. A rise in serum galactomannan during combination therapy with voriconazole and anidulafungin should be interpreted as treatment failure and not attributed to a paradoxical reaction related to echinocandin treatment.

Diagnostic and therapeutic challenges in a liver transplant recipient with central nervous system invasive aspergillosis

This is a case report of central nervous system (CNS) invasive aspergillosis (IA) in a liver transplant recipient, which illustrates the utility of enzyme-based diagnostic tools for the timely and accurate diagnosis of IA, the treatment challenges and poor outcomes associated with CNS IA in liver transplant recipients.

Multiplex PCR for rapid and improved diagnosis of bloodstream infections in liver transplant recipients

This prospective study evaluated the utility of the SeptiFast (SF) test in detecting 25 clinically important pathogens in 225 blood samples from 170 intensive care unit (ICU) patients with suspected sepsis after liver transplantation (LTX) or after other major abdominal surgery (non-LTX). SF yielded a significantly higher positivity rate in the LTX group (52.3%) than in the non-LTX group (30.5%; P = 0.0009). SF may be a powerful tool for the early diagnosis of bloodstream infections in LTX patients.