Invasive aspergillosis in liver transplant recipients: outcome comparison of therapy with amphotericin B lipid complex and a historical cohort treated with conventional amphotericin B

Donor-derived renal allograft mucormycosis in a combined liver and kidney transplantation: Case report and review of the literature

Mucormycosis infrequently may present with isolated renal involvement. Among solid organ transplant recipients, renal allograft mucormycosis has been most often associated with medical tourism or transplantation outside of the western world. We report a case of an HIV/HCV co-infected woman who underwent simultaneous liver and kidney transplantation with a Public Health Service increased risk donor organ. 16 days after transplant, she developed massive hematuria and was found to have renal allograft Rhizopus spp. involvement, we surmise to have been from donor-derived infection. Therapy included nephrectomy, debridement, liposomal amphotericin B, and posaconazole with survival. We reviewed PubMed indexed, English-language cases of isolated renal mucormycosis in general, in HIV/AIDS, and from donor-derived renal allograft infections.

Prevalence and outcome of invasive pulmonary aspergillosis in critically ill patients with liver cirrhosis: an observational study

Invasive pulmonary aspergillosis (IPA) is an important cause of morbidity/mortality in critically ill patients with endstage liver disease. Therefore, aim of this study is to predict the prevalence and outcome of IPA in critically ill patients with underlying liver cirrhosis and evaluation of the necessity Glactomannan (GM) screening in serum and bronchoalveolar lavage (BAL) in this cohort. In total 12 out of 84 patients (14%) had probable IPA. The mean optical density index (ODI) bronchoalveolar lavage (BAL) GM index was 3.6 ± 1.5 (Range: 1.7–5.7). An overall sensitivity of 90% (95% CI 86–96%) and specificity of 85% (95% CI 81–88%) was found for the BAL GM in IPA. Acute Physiology And Chronic Health Evaluation (APACHE II), sequential organ failure assessment (SOFA) as well the model of endstage liver disease (MELD) score were significantly higher in the probable IPA group as compared to the No IPA group (26 versus 21, p < 0.001 and 14 versus 10, p < 0.044). Length of intensive care unit (ICU) stay was significantly longer in probable IPA patients (16 versus 10 days, p < 0.027) and mortality rate was significantly higher in probable IPA patients (100% versus 65%, p < 0.001) as compared to No IPA patients. APACHE II and MELD score were independently associated with higher mortality rate using multivariate logistic regression (p = 0.025 and p = 0.034). In conclusion, IPA has a relevant impact on outcome. Screening for IPA is indicated, easy to perform and a necessity to improve outcome.

Diagnosis and management of Aspergillus diseases: executive summary of the 2017 ESCMID-ECMM-ERS guideline

The European Society for Clinical Microbiology and Infectious Diseases, the European Confederation of Medical Mycology and the European Respiratory Society Joint Clinical Guidelines focus on diagnosis and management of aspergillosis. Of the numerous recommendations, a few are summarized here. Chest computed tomography as well as bronchoscopy with bronchoalveolar lavage (BAL) in patients with suspicion of pulmonary invasive aspergillosis (IA) are strongly recommended. For diagnosis, direct microscopy, preferably using optical brighteners, histopathology and culture are strongly recommended. Serum and BAL galactomannan measures are recommended as markers for the diagnosis of IA. PCR should be considered in conjunction with other diagnostic tests. Pathogen identification to species complex level is strongly recommended for all clinically relevant Aspergillus isolates; antifungal susceptibility testing should be performed in patients with invasive disease in regions with resistance found in contemporary surveillance programmes. Isavuconazole and voriconazole are the preferred agents for first-line treatment of pulmonary IA, whereas liposomal amphotericin B is moderately supported. Combinations of antifungals as primary treatment options are not recommended. Therapeutic drug monitoring is strongly recommended for patients receiving posaconazole suspension or any form of voriconazole for IA treatment, and in refractory disease, where a personalized approach considering reversal of predisposing factors, switching drug class and surgical intervention is also strongly recommended. Primary prophylaxis with posaconazole is strongly recommended in patients with acute myelogenous leukaemia or myelodysplastic syndrome receiving induction chemotherapy. Secondary prophylaxis is strongly recommended in high-risk patients. We strongly recommend treatment duration based on clinical improvement, degree of immunosuppression and response on imaging.

Recent advances in antifungal pharmacotherapy for invasive fungal infections

Invasive fungal infections carry significant morbidity and mortality. Candida species have become one of the most frequent causes of bloodstream infections, and infections caused by molds such as Aspergillus are becoming more frequent in immunocompromised patients. As this population grows, more invasive fungal infections can be anticipated. In the past, treatment options have been limited for many of these infections due to toxicity and efficacy concerns with the available antifungals. Fortunately, the past few years have brought exciting developments in antifungal pharmacotherapy. Lipid-based formulations of amphotericin B were introduced in the 1990s to attenuate adverse effects caused by amphotericin B deoxycholate (Fungizone, Bristol-Myers Squibb). Most recently, the echinocandins have been added to our antifungal regimen with the introduction of caspofungin (Cancidas, Merck and Co.) and voriconazole (Vfend, Pfizer), a new triazole, has come to market. The introduction of the echinocandins has invigorated the discussion about combination antifungal therapy. Evidence-based studies using these new agents are accumulating, and they are assuming important roles in the pharmacotherapy of invasive fungal infections in seriously ill and complex patients.

[Antifungal therapy update: new drugs and medical uses]

Increases in the rates of fungal infections, as well as their associated morbidity and mortality has led to a need for additional antifungal agents. The most common serious fungal agents in immunosuppressed and critically ill patients are Candida spp. and Aspergillus spp., although other emerging fungi must be considered. Rational, early systemic antifungal treatment should be based on diagnostic imaging techniques and conventional mycological and non-culture-based procedures. While the availability of new therapeutic options is an important advance, antifungal therapy has become increasingly complex. In addition to the available antifungal armamentarium, recent research has resulted in the introduction of three new antifungal agents: micafungin, anidulafungin, and posaconazole. This article provides an update, based on the latest scientific evidence, of the clinical efficacy, pharmacokinetics, safety and dosing of antifungal drugs administered in the management of Candida spp., Aspergillus spp., Cryptococcus spp., Zygomycetes, Scedosporium spp. and Fusarium spp.

[Guidelines for the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC). 2011 Update]

The guidelines on the treatment of invasive fungal disease by Aspergillus spp. and other fungi issued by the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) are presented. These recommendations are focused on four clinical categories: oncology-haematology patients, solid organ transplant recipients, patients admitted to intensive care units, and children. An extensive review is made of therapeutical advances and scientific evidence in these settings. These guidelines have been prepared according the SEIMC consensus rules by a working group composed of specialists in infectious diseases, clinical microbiology, critical care medicine, paediatrics and oncology-haematology. Specific recommendations on the prevention of fungal infections in these patients are included.

Invasive fungal infections in liver transplantation

Invasive fungal infections (IFIs) in immunocompromised patients, particularly liver transplant recipients, are the subject of increasing clinical attention. Although the overall incidence of fungal infections in liver transplant recipients has declined due to the early treatment of high-risk patients, the overall mortality rate remains high, particularly for invasive candidiasis and aspergillosis. IFIs after liver transplantation are strongly associated with negative outcomes, increasing the cost to recipients. Numerous studies have attempted to determine the independent risk factors related to IFIs and to reduce the morbidity and mortality with empirical antifungal prophylaxis after liver transplantation. Unfortunately, fungal infections are often diagnosed too late; symptoms can be mild and non-specific even with dissemination. Currently, no consensus exists on which patients should receive antifungal prophylaxis, when prophylaxis should be given, which antifungal agents should be used, and what duration is effective. This review highlights the types of IFI, risk factors, diagnosis, antifungal prophylaxis, and treatment after liver transplantation. With the early identification of patients at high risk for IFIs and the development of new molecular diagnostic techniques for early detection, the role of antifungal compounds in fungal infection prophylaxis needs to be established to improve the survival rate and quality of life in liver transplant patients.

Epidemiology of invasive aspergillosis and risk factors in non neutropaenic patients

INTRODUCTION

Invasive aspergillosis is a major cause of mortality in allogeneic bone marrow transplant recipients and patients treated for blood malignancies. The diagnostic tools, treatments and preventive strategies, essentially developed for neutropaenic patients, have not been assessed in populations whose immune systems are considered to be competent.

STATE OF THE ART

Beside the standard picture of chronic Aspergillus infection, the incidence of invasive aspergillosis is increasing in non neutropaenic patients, such as those with chronic lung diseases or systemic disease treated with long-term immunosuppressive drugs and solid organ transplant recipients. This study reviews the specific features of invasive aspergillosis in non neutropaenic subjects (NNS) and discusses the value of the diagnostic tools and treatment in this population.

PROSPECTS

A better understanding of the pathophysiology and the epidemiological characteristics of invasive aspergillosis would provide a means of adapting the staging and classification of the disease for NNS.

CONCLUSIONS

Invasive aspergillosis is under diagnosed in NNS who may already be colonised when they receive immunosuppressive treatment; this can lead to an adverse outcome in patients who are considered to be a moderate risk population.

Fungal infections in solid organ transplantation

Renal, liver, heart and lung transplantation are now considered to be the standard therapeutic interventions in patients with end-stage organ failure. Infectious complications following transplantation are relatively common due to the transplant recipients overall immunosuppressed status. The incidence of invasive mycoses following solid organ transplant ranges from 5 to 42% depending on the organ transplanted. These mycoses are associated with high overall mortality rates. Candida and Aspergillus spp. produce most of these infections. This article will review the risk factors, clinical presentation and treatment of invasive fungal infections in solid organ transplant patients, and evaluate the role of prophylactic therapy in this group of patients.

Caspofungin-resistant Aspergillus flavus after heart transplantation and mechanical circulatory support: a case report

Invasive aspergillosis (IA) is a severe complication in the post-transplant period in recipients of solid organs. Therefore, early diagnosis and specific therapy of fungal infections in these patients are indispensable. We report the case of a 49-year-old patient, who suffered from IA after cardiac transplantation, which was complicated by post-transplant right heart failure requiring mechanical circulatory support using veno-arterial extracorporeal membrane oxygenation and a right ventricular assist device. Despite antifungal treatment, the patient died 3 weeks after transplantation because of multi-organ failure secondary to IA. The isolated Aspergillus strains exhibited in vitro resistance to caspofungin.

Risk factors for invasive aspergillosis in living donor liver transplant recipients

Invasive aspergillosis (IA) is a severe complication of liver transplantation. Risk factors for IA after deceased donor liver transplantation (DDLT) have been presented in several reports, but are not well established for living donor liver transplant recipients. Here, a retrospective case-control study was performed. Five cases with IA were investigated after living donor liver transplantation (LDLT) between January 1999 and December 2002 at Kyoto University Hospital. For comparison, living donor liver transplant recipients without IA were taken as controls. These patients had undergone LDLT 1 month before or after each IA case and had the same survival times as the latter. We evaluated the clinical and laboratory findings for both groups up until their demise. Patients with IA after LDLT had a very poor prognosis. By univariate analysis, risk factors for IA were preoperative intensive care unit stay (P = 0.02) and preoperative steroid administration (P = 0.02). Preoperative steroid administration for fulminant hepatitis possibly predisposed to the development of IA after LDLT.

Gram-Negative Outer and Inner Membrane Models: Insertion of Cyclic Cationic Lipopeptides

Most Gram-negative bacteria are susceptible to polymyxin B (PxB), and development of resistance to this cationic lipopeptide is very rare. PxB mechanism of action involves interaction with both the outer membrane (OM) and the inner membrane (IM) of bacteria. For the design of new antibiotics based on the structure of PxB and with improved therapeutic indexes, it is essential to establish the key features of PxB that are important for activity. We have used an approach based on mimicking the outer layers of the OM and the IM of Gram-negative bacteria using monolayers of lipopolysaccharide (LPS) or anionic 1-palmitoyl-2-oleoylglycero-sn-3-phosphoglycerol (POPG), respectively, and using a combination of penetration assay, analysis of pressure/area curves, and Brewster angle microscopy to monitor surface morphology changes. Synthetic analogue sp-B maintains the basic structural characteristics of the natural compound and interacts with the OM and the IM in a similar way. Analogue sp-C, with a mutation of the sequence [d-Phe6-Leu7] into [d-Phe6-Dab7], shows that this hydrophobic domain is involved in LPS binding. The significant role of the positive charges is demonstrated with sp-Dap analogue, where l-alpha,gamma-diaminobutyric acid residues Dab1 and Dab8 are replaced by l-alpha,gamma-diaminopropionic acid (Dap), resulting in lower degrees of insertion in both LPS and PG monolayers. The importance of the N-terminal acyl chain is demonstrated with polymyxin B nonapeptide (PxB-np). PxB-np shows lower affinity for LPS compared to PxB, sp-B, or sp-C, but it does not insert into PG monolayers, although it binds superficially to the anionic film. Since PxB microbial killing appears to be mediated by osmotic instability due to OM-IM phospholipid exchange, the ability of the different peptides to induce membrane-membrane lipid exchange has been studied by use of phospholipid unilamellar vesicles. Results indicate that cationic amphipathicity determines peptide activity.

The role of echinocandins, extended-spectrum azoles, and polyenes to treat opportunistic moulds and candida

Three classes of antifungals--polyenes, extended-spectrum azoles, and echinocandins--are now available for treating systemic fungal infections. Guidance for the appropriate use of this expanded variety of antifungals may come from recent clinical trials. Extended-spectrum azoles have excellent in vitro activity against Aspergillus and have been shown to improve clinical outcomes. For Zygomycetes, along with the lipid formulations of amphotericin, of the new agents, only posaconazole has activity. For Candida, the echinocandins offer a broad spectrum of activity. These new agents offer less toxicity and potentially improved efficacy in these difficult infections.

Antifungal prophylaxis in liver transplant patients: a systematic review and meta-analysis

We performed a meta-analysis to determine whether antifungal prophylaxis decreases infectious morbidity and mortality in liver transplant patients. We searched for randomized trials dealing with prophylaxis with systemic antifungal agents. We used a fixed effect model, with risk ratio (RR) and 95% confidence interval (CI); we assessed study quality for heterogeneity and publication bias. Six studies (5 double-blind), for a total of 698 patients, compared fluconazole, itraconazole, or liposomal amphotericin to placebo (5 studies) or oral nystatin. Prophylaxis reduced colonization (RR, 0.45; CI, 0.37-0.55), total proven fungal infections (RR, 0.31; CI, 0.21-0.46), which included both superficial (RR, 0.27; CI, 0.16-0.45) and invasive (RR, 0.33; CI, 0.18-0.59) infections, and mortality attributable to fungal infection (RR, 0.30; CI, 0.12-0.75). Prophylaxis did not affect overall mortality (RR, 1.06; CI, 0.69-1.64) or empiric treatment for suspected fungal infection (RR, 0.80; CI, 0.39-1.67). The beneficial effect of antifungal prophylaxis was predominantly associated with the reduction of Candida albicans infection and mortality attributable to C. albicans. Compared to controls, however, patients receiving prophylaxis experienced a higher proportion of episodes of non-albicans Candida, and in particular of C. glabrata. No beneficial effect on invasive Aspergillus infection was observed. In conclusion, our analysis shows a clear, though limited, beneficial effect of antifungal prophylaxis in liver transplant patients. Concerns about the selection of triazole-resistant Candida strains, however, are realistic, and the potential disadvantages of prophylaxis should be weighed against the established benefits.

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

BACKGROUND

: The efficacy of the combination of voriconazole and caspofungin when used as primary therapy for invasive aspergillosis in organ transplant recipients has not been defined.

METHODS

: Transplant recipients who received voriconazole and caspofungin (n=40) as primary therapy for invasive aspergillosis (proven or probable) in a prospective multicenter study between 2003 and 2005 were compared to a control group comprising a cohort of consecutive transplant recipients between 1999 and 2002 who had received a lipid formulation of AmB as primary therapy (n=47). In vitro antifungal testing of Aspergillus isolates to combination therapy was correlated with clinical outcome.

RESULTS

: Survival at 90 days was 67.5% (27/40) in the cases, and 51% (24/47) in the control group (HR 0.58, 95% CI, 0.30-1.14, P=0.117). However, in transplant recipients with renal failure (adjusted HR 0.32, 95% CI: 0.12-0.85, P=0.022), and in those with A. fumigatus infection (adjusted HR 0.37, 95% CI: 0.16-0.84, P=0.019), combination therapy was independently associated with an improved 90-day survival in multivariate analysis. No correlation was found between in vitro antifungal interactions of the Aspergillus isolates to the combination of voriconazole and caspofungin and clinical outcome.

CONCLUSIONS

: Combination of voriconazole and caspofungin might be considered preferable therapy for subsets of organ transplant recipients with invasive aspergillosis, such as those with renal failure or A. fumigatus infection.

Viral and fungal infections after liver transplantation--part II

Viral and fungal infections in liver transplant recipients are important to recognize and treat early because of their association with substantial morbidity and mortality. Some viruses, such as cytomegalovirus and human herpesvirus 6, have immunomodulatory properties and can facilitate other infections, including fungal infections. Cytomegalovirus has long been recognized as an important virus in transplantation, but in the past decade other viruses have also received attention in the medical literature because of their association with particular clinical syndromes. Although human herpesvirus 6 has been associated with fever, rash, and encephalitis, a direct cause-and-effect relationship is still lacking. Human herpesvirus 8 has been found to be the cause of Kaposi sarcoma. Molecular techniques (e.g., pp65 antigenemia and polymerase chain reaction) that have been introduced for routine diagnosis of viruses have facilitated the diagnosis of asymptomatic viral infections and the institution of preemptive therapy. Nonetheless, the diagnosis of invasive fungal infections in liver transplant recipients is often delayed and thus associated with high mortality. Despite the use of new antifungal agents in clinical practice and the reduced incidence of fungal infections because of antifungal prophylaxis regimens, mortality has not decreased. Future patient outcomes may improve with early identification of patients who have risk factors for invasive fungal infections and with the development of new molecular diagnostic techniques for early detection.

Advances and challenges in management of invasive mycoses

Invasive mycoses pose a major diagnostic and therapeutic challenge. Advances in antifungal agents and diagnostic methods offer the potential for improved outcomes in patients with these infections, which are often lethal. Many fungal pathogens occur almost exclusively in opportunistic settings--in the immunocompromised host--and these infections are the focus of this review. Several areas of ongoing challenge remain, including the emergence of resistant organisms and the absence of reliable markers for early identification of patients at risk of developing invasive fungal disease. This Seminar reviews the changing epidemiology of invasive mycoses, new diagnostic methods, and recent therapeutic options and current management strategies for these opportunistic pathogens.

Risk stratification and targeted antifungal prophylaxis for prevention of aspergillosis and other invasive mold infections after liver transplantation

Antifungal prophylaxis has been proposed for liver transplant recipients at increased risk for invasive mold infection. Risk factors for invasive mold infection after liver transplantation were selected to divide recipients into 3 groups: (1) high risk-transplantation on hemodialysis or delay of hospital discharge beyond day 7 after transplantation because of allograft or renal insufficiency; (2) intermediate risk-retransplantation or transplantation for fulminant hepatic failure; (3) low risk-absence of conditions in groups 1 and 2. During an intervention period (February 1999-April 2001), prophylactic administration of a lipid complex of amphotericin (Abelcet) at 5 mg/kg intravenously every 24 to 48 hours was recommended for high-risk recipients. The frequency of mold infection was compared to that of a preintervention period (February 1998-January 1999) when antifungal prophylaxis was not provided. During the intervention period, invasive mold infection developed in 2 (6%) of 35 high-risk recipients, 0 of 28 intermediate-risk recipients, and 1 (0.5%) of 187 low-risk recipients. Overall, of 58 liver transplant recipients, 3 (5%) developed an invasive mold infection during the preintervention period, compared with 3 (1%) of 250 during the intervention period (P = 0.08). The only death from invasive mold infection occurred during the preintervention period. Rates of pulse corticosteroid treatment of rejection and cytomegalovirus infection were lower during the intervention period. In conclusion, readily identifiable patient characteristics can be used to stratify liver transplant recipients for risk of invasive mold infection. Antifungal prophylaxis given to high-risk recipients may provide cost-effective prevention of these infections.

Simple chemical extraction method for DNA isolation from Aspergillus fumigatus and other Aspergillus species

DNA was successfully isolated from numerous Aspergillus spp. by use of a commercial kit. DNA that was easily digested and yielded PCR products up to 8.5 kb in size was recovered from broth or agar cultures. The ease and speed of this protocol provide an alternative to physical methods of DNA isolation.

Amphotericin B lipid complex for the treatment of invasive fungal infections

Amphotericin B lipid complex (ABLC; Abelcet, Enzon Pharmaceuticals) has become the dominant marketed lipid amphotericin B compound to emerge since the approval of these agents from the mid-1990s onwards. This agent is a 1:1 combination of amphotericin B and a lipid moiety consisting of dimyristoyl phosphatidylcholine and dimyrisoyl phosphatidylcholine, which exists in a ribbon-like molecular structure. ABLC undergoes rapid reticuloendothelial uptake from the circulation and achieves significantly higher tissue concentrations in the liver, spleen and lung compared to comparably dosed conventional amphotericin B. ABLC is approved by the FDA for all mycoses in amphotericin B-intolerant or -refractory infection. Randomised, controlled trials of amphotericin B have shown comparable efficacy in candidiasis and an improved outcome in invasive aspergillosis versus historical controls. ABLC has demonstrated a reduced incidence of nephrotoxicity and infusion reactions versus amphotericin B. Comparative studies against other lipid formulations are quite limited and have shown variable differences in infusion toxicity, nephrotoxicity, hepatotoxicity and clinical efficacy. Postapproval experience has shown substantial efficacy for less common mycotic pathogens including zygomycosis. The precise position of ABLC versus both other lipid formulations and expanding formulary of new antifungal agents is in flux. Future studies which examine its clinical efficacy, role in combination therapy, toxicity and cost-effectiveness in these complex patients are needed.