Invasive aspergillosis. Disease spectrum, treatment practices, and outcomes. I3 Aspergillus Study Group

Azole Resistance in Aspergillus fumigatus: Can We Retain the Clinical Use of Mold-Active Antifungal Azoles?

Azole resistance in Aspergillus fumigatus has emerged as a global health problem. Although the number of cases of azole-resistant aspergillosis is still limited, resistance mechanisms continue to emerge, thereby threatening the role of the azole class in the management of diseases caused by Aspergillus. The majority of cases of azole-resistant disease are due to resistant A. fumigatus originating from the environment. Patient management is difficult due to the absence of patient risk factors, delayed diagnosis, and limited treatment options, resulting in poor treatment outcome. International and collaborative efforts are required to understand how resistance develops in the environment to allow effective measures to be implemented aimed at retaining the use of azoles both for food production and human medicine.

The interplay between inflammasome activation and antifungal host defense

Fungal infections cause significant morbidity and mortality in humans, and they are a growing problem due to the increased usage of broad-spectrum antibiotics and immunosuppressive therapies. The equilibrium between the commensal microbial flora and the immune system that protects the host against invasive fungal infection is disturbed during disease, and understanding this disturbed balance is important to develop new therapeutic interventions for the treatment of fungal infection. In the context of tolerating fungi during colonization and eliciting a vigorous immune response to eliminate invading fungal pathogens when needed, the inflammasome has been identified as an integral component of antifungal host defense. It contributes to mucosal host defense by regulating T-helper 17 (Th17) cell responses, and contributes to protective responses such as neutrophil influx during fungal sepsis. Several aspects are important for understanding the role of the inflammasome for antifungal host defense, such as the role of fungal cell wall morphology and its components in triggering the inflammasome, the pattern recognition pathways and downstream signaling cascades involved in the activation of the inflammasome, and the effects of inflammasome activation during fungal infection. The future perspectives of inflammasome research in fungal immunology, with emphasis on targeting the inflammasome for the design of future immunotherapies, is also discussed.

Fungal Mycotic Aneurysm of the Internal Carotid Artery Associated with Sphenoid Sinusitis in an Immunocompromised Patient: A Case Report and Review of the Literature

In immunocompromised patients, invasive molds such as Aspergillus and Mucor can lead to locally aggressive angioinvasive infections that are often life-threatening. A particularly devastating complication is the development of a fungal mycotic aneurysm resulting from invasion of the arterial wall. Due to anatomic contiguity, the sphenoid sinus provides potential access for these fungi, which often colonize the respiratory sinuses, into the cavernous sinus and internal carotid artery (ICA), thus leading to the formation of ICA aneurysms. The ideal treatment of fungal ICA aneurysms includes a combination of surgical debridement and long-term effective antifungal therapy, but the role of endoscopic resection and the duration of antimicrobials are poorly defined. Here, we present the case of a 71-year-old immunocompromised patient who developed an ICA mycotic aneurysm, associated with a proven invasive fungal infection (presumptively Mucorales) of the sphenoid sinuses, as defined by EORTC/MSG criteria, and who survived after undergoing coil embolization with parent vessel sacrifice of the aneurysm in combination with liposomal amphotericin B. We also review the literature for published cases of invasive fungal sphenoid sinusitis associated with mycotic aneurysms of the ICA and provide a comparative analysis .

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.

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.

Postoperative Bone Graft Displacement: An Unusual Sign of Infection Following Posterior Spinal Fusion

We describe a case of a spinal fusion site infection, which was first suggested on plain radiographs due to interval displacement and partial dissolution of the bone graft material. These radiographic findings occurred 4 weeks before the infection became clinically evident. Cultures taken during eventual surgical debridement grew Aspergillus fumigatus. This case emphasizes the importance of noting changes in bone graft material in addition to the routine evaluation of alignment and hardware in patients who have undergone posterior spinal fusion.

Application of Culture-Independent Rapid Diagnostic Tests in the Management of Invasive Candidiasis and Cryptococcosis

The diagnosis of invasive candidiasis (IC) and cryptococcosis is often complicated by slow and insensitive culture-based methods. Such delay results in poor outcomes due to the lack of timely therapeutic interventions. Advances in serological, biochemical, molecular and proteomic approaches have made a favorable impact on this process, improving the timeliness and accuracy of diagnosis with resultant improvements in outcome. This paper will serve as an overview of recent developments in the diagnostic approaches to infections due to these important yeast-fungi.

Clinical Features and Prognosis of Invasive Pulmonary Aspergillosis in Korean Children with Hematologic/Oncologic Diseases

Invasive pulmonary aspergillosis (IPA) is the most frequent form of invasive fungal diseases in immunocompromised patients. However, there are only a few studies on IPA in immunocompromised children in Korea. This study was designed to characterize IPA in Korean children with hematologic/oncologic diseases. Medical records of children with hematologic/oncologic diseases receiving antifungal therapy were reviewed. The enrolled children were divided into the IPA group (proven and probable IPA) and non-IPA group, and the clinical characteristics and prognosis were compared between the two groups. During the study period, 265 courses of antifungal therapy were administered to 166 children. Among them, two (0.8%) episodes of proven IPA, 35 (13.2%) of probable IPA, and 52 (19.6%) of possible IPA were diagnosed. More children in the IPA group suffered from neutropenia lasting for more than two weeks (51.4% vs. 21.9%, P<0.001) and showed halo signs on the chest computed tomography (78.4% vs. 40.7%, P<0.001) than in the non-IPA group. No other clinical factors showed significant differences between the two groups. Amphotericin B deoxycholate was administered as a first line antifungal agent in 33 (89.2%) IPA group episodes, and eventually voriconazole was administered in 27 (73.0%) episodes. Ten (27.0%) children in the IPA group died within 12 weeks of antifungal therapy. In conclusion, early use of chest computed tomography to identify halo signs in immunocompromised children who are expected to have prolonged neutropenia can be helpful for early diagnosis of IPA and improving prognosis of children with IPA.

A comparative study of itraconazole in various dose schedules in the treatment of pulmonary aspergilloma in treated patients of pulmonary tuberculosis

INTRODUCTION

The optimal dose, duration, and efficacy of itraconazole in Indian patients of pulmonary aspergilloma (PA) are not clearly defined. Therefore, a study was carried out, to resolve these issues in diagnosed cases of PA complicating old treated patients of pulmonary tuberculosis.

MATERIALS AND METHODS

The study patients randomly received itraconazole either in a fixed dose schedule of 200 mg (group I), 200 mg twice daily (group II) or a variable dose schedule (group III), for 12 months. All the patients were followed up for the entire duration of the study for clinical, radiological, and immunological response. The side effects were recorded as and when reported by the patients and managed symptomatically.

RESULTS

A total of 60 patients were enrolled, 20, in each group. There were no intergroup differences with regard to age, sex, body weight, smoking status, alcohol intake, symptoms, Potassium hydroxide (KOH) mount, fungal culture, pattern of radiological lesions or anti-aspergillus antibodies (anti-Asp-Ab) titers. The radiological response was poor in group I patients, as compared to the other groups, at two months (P < 0.05). The dose of itraconazole was increased in five of the patients in group I due to poor response. A higher number of group II patients suffered side effects and the dose of itraconazole had to be decreased in three of these patients, but none of the patients on a variable dose schedule required a change in dose schedule.

CONCLUSION

Thus, a weight-based variable dose schedule of itraconazole was found to be a more effective and safer modality in the management of PA than a fixed dose schedule.

Cutaneous Invasive Aspergillosis: Retrospective Multicenter Study of the French Invasive-Aspergillosis Registry and Literature Review

Invasive aspergillosis (IA) has poor prognosis in immunocompromised patients. Skin manifestations, when present, should contribute to an early diagnosis. The authors aimed to provide prevalence data and a clinical and histologic description of cutaneous manifestations of primary cutaneous IA (PCIA) and secondary CIA (SCIA) in a unique clinical series of IA and present the results of an exhaustive literature review of CIA. Cases of proven and probable IA with cutaneous manifestations were retrospectively extracted from those registered between 2005 and 2010 in a prospective multicenter aspergillosis database held by the National Reference Center for Invasive Mycoses and Antifungals, Pasteur Institute, France. Patients were classified as having PCIA (i.e., CIA without extracutaneous manifestations) or SCIA (i.e., disseminated IA). Among the 1,410 patients with proven or probable IA, 15 had CIA (1.06%), 5 PCIA, and 10 SCIA. Hematological malignancies were the main underlying condition (12/15). Patients with PCIA presented infiltrated and/or suppurative lesions of various localizations not related to a catheter site (4/5), whereas SCIA was mainly characterized by disseminated papules and nodules but sometimes isolated nodules or cellulitis. Histologic data were available for 11 patients, and for 9, similar for PCIA and SCIA, showed a dense dermal polymorphic inflammatory infiltrate, with the epidermis altered in PCIA only. Periodic acid Schiff and Gomori-Grocott methenamine silver nitrate staining for all but 2 biopsies revealed hyphae compatible with Aspergillus. Aspergillus flavus was isolated in all cases of PCIA, with Aspergillus fumigatus being the most frequent species (6/10) in SCIA. Two out 5 PCIA cases were treated surgically. The 3-month survival rate was 100% and 30% for PCIA and SCIA, respectively. Our study is the largest adult series of CIA and provides complete clinical and histologic data for the disease. Primary cutaneous IA should be recognized early, and cases of extensive necrosis should be treated surgically; its prognosis markedly differs from that for SCIA. Any suppurative, necrotic, papulonodular, or infiltrated skin lesion in an immunocompromised patient should lead to immediate biopsy for histologic analysis and mycological skin direct examination and culture.

How to treat fungal infections in ICU patients

Fungal infections represent a major burden in the critical care setting with increasing morbidity and mortality. Candidiasis is the leading cause of such infections, with C. albicans being the most common causative agent, followed by Aspergillosis and Mucormycosis. The diagnosis of such infections is cumbersome requiring increased clinical vigilance and extensive laboratory testing, including radiology, cultures, biopsies and other indirect methods. However, it is not uncommon for definitive evidence to be unavailable. Risk and host factors indicating the probability of infections may greatly help in the diagnostic approach. Timely and adequate intervention is important for their successful treatment. The available therapeutic armamentarium, although not very extensive, is effective with low resistance rates for the newer antifungal agents. However, timely and prudent use is necessary to maximize favorable outcomes.

Assessment Techniques to Detect Aspergillus fumigatus in Different Samples of Immunosuppressed Male Western Albino Rats

Background:

There are several conventional, immunological and molecular techniques to diagnose the fungi that cause aspergillosis in biological samples; these methods have some advantages and disadvantages.

Objectives:

The current study aimed to evaluate different methods used in identification and diagnosis of fungi causing aspergillosis.

Materials and Methods:

Male Western Albino rats were provided by Animal Care Unit at Faculty of Pharmacy, King Saud University. After adaptation for a reasonable period, rat's immunity was debilitated by injection of cyclophosphamide (i.p.); the infection was induced by injecting (i.v.) the prepared suspension of Aspergillus fumigatus spores. Blood samples, lung tissue, lung fluid smears and nasal fluid smears were obtained during the periods before and after injection. Isolation of fungus was carried out by synthetic media; and macro- and micro-characteristics were studied to identify the fungus. Enzyme-linked immunesorbent (ELISA) and LightCycler-based PCR was employed to check the existence of the fungus in blood samples.

Results:

The results indicated that all methods were unable to diagnose the A. fumigatus on the following day of infection except ELISA method; however, culturing methods varied according to the type of vital samples where lung tissue and lung fluid smears were the best. Moreover, more than half of the samples used in the culturing techniques had negative results. The highest rate of the cases diagnosed by ELISA and polymerase chain reaction (PCR) was recorded during the second week following the infection, and then it declined gradually till the end of the experiment. The molecular methods showed high efficiency followed by ELISA.

Conclusions:

It could be concluded that the best methods to identify A. fumigatus were molecular methods; however, the early diagnosis requires the enzymatic-immunological methods (ELISA). The current study recommends the integration among all possible techniques whenever the facilities are available. But when only microbiological methods are used, samples should be collected from different organs of the infected hosts.

Invasive pulmonary aspergillosis - case report and review of literature

Invasive pulmonary aspergillosis (IPA) is a severe fungal infection with a high mortality rate. The incidence of IPA is on the rise due to an increase in the number of patients undergoing transplants and receiving chemotherapy and immunosuppressive therapy. Diagnosis is challenging due to the non-specific nature of symptoms. Voriconazole is the mainstay of therapy. We present a case of an elderly woman presenting with acute bronchitis and asthma exacerbation, who succumbed to overwhelming IPA. It is uncommon for IPA to develop in patients on short-term steroid therapy for asthma exacerbation. The possibility of aspergillosis in immunocompetent patients should be considered in those on systemic steroids and deteriorating pulmonary functions.

Clinical implications of interferon-γ genetic and epigenetic variants

Interferon-γ (IFN-γ) is an integral and critical molecule of the immune system, with multiple functions, mostly related to the T helper type 1 (Th1) response to infection. It is critical for defence against mycobacterial infection and is of increasing interest in defence against fungi. In this article, we review the genetic and epigenetic variants affecting IFN-γ expression and investigate its role in disease, with an emphasis on fungal diseases such as invasive and chronic pulmonary aspergillosis. Over 347 IFN-γ gene variants have been described, in multiple ethnic populations. Many appear to confer a susceptibility to disease, especially tuberculosis (TB) and hepatitis, but also some non-infectious conditions such as aplastic anaemia, cervical cancer and psoriasis. Several epigenetic modifications are also described, increasing IFN-γ expression in Th1 lymphocytes and reducing IFN-γ expression in Th2 lymphocytes. Recombinant IFN-γ administration is licensed for the prophylaxis of infection (bacterial and fungal) in patients with the phagocyte functional deficiency syndrome chronic granulomatous disease, although the benefits appear limited. Interferon-γ therapy is given to patients with profound defects in IFN-γ and interleukin-12 production and appears to be beneficial for patients with invasive aspergillosis and cryptococcal meningitis, but the studies are not definitive. A high proportion of patients with chronic pulmonary aspergillosis are poor producers of IFN-γ in response to multiple stimuli and could also benefit from IFN-γ administration. The investigation and management of patients with possible or demonstrated IFN-γ deficiency in adulthood is poorly studied and could be greatly enhanced with the integration of genetic data.

Current state and future perspectives of loop-mediated isothermal amplification (LAMP)-based diagnosis of filamentous fungi and yeasts

Loop-mediated isothermal amplification is a rather novel method of enzymatic deoxyribonucleic acid amplification which can be applied for the diagnosis of viruses, bacteria, and fungi. Although firmly established in viral and bacterial diagnosis, the technology has only recently been applied to a noteworthy number of species in the filamentous fungi and yeasts. The current review gives an overview of the literature so far published on the topic by discussing the different groups of fungal organisms to which the method has been applied. Moreover, the method is described in detail as well as the different possibilities available for signal detection and quantification and sample preparation. Future perspective of loop-mediated isothermal amplification-based assays is discussed in the light of applicability for fungal diagnostics.

Cerebral aspergillosis in a patient with leprosy and diabetes: a case report

Background

Opportunistic fungi are dispersed as airborne, ground and decaying matter. The second most frequent extra-pulmonary disease by Aspergillus is in the central nervous system.

Case presentation

The case subject was 55 years old, male, mulatto, and an assistant surveyor residing in Teresina, Piauí. He presented with headache, seizures, confusion, fever and left hemiparesis upon hospitalization in 2006 at Hospital São Marcos. Five years previously, he was diagnosed with diabetes mellitus, and 17 months previously he had acne margined by hyperpigmented areas and was diagnosed with leprosy. Laboratory tests indicated leukocytosis and magnetic resonance imaging showed an infarction in the right cerebral hemisphere. Cerebrospinal fluid examination showed 120 cells/mm³ and was alcohol-resistant bacilli negative. Trans-sphenoidal surgery with biopsy showed inflammation was caused by infection with Aspergillus fumigatus. We initiated use of parenteral amphotericin B, but his condition worsened. He underwent another surgery to implant a reservoir of Ommaya–Hickmann, a subcutaneous catheter. We started liposomal amphotericin B 5 mg/kg in the reservoir on alternate days. He was discharged with a prescription of tegretol and fluconazole.

Conclusion

This report has scientific interest because of the occurrence of angioinvasive cerebral aspergillosis in a diabetic patient, which is rarely reported. In conclusion, we suggest a definitive diagnosis of cerebral aspergillosis should not postpone quick effective treatment.

[Invasive pulmonary aspergillosis in patients with chronic obstructive pulmonary disease]

Invasive pulmonary aspergillosis (IPA) is a common infection in immunocompromised patients with hematological malignancies or allogenic stem cell transplantation, and is less frequent in the context of chronic obstructive pulmonary disease (COPD). Mucociliary activity impairment, immunosuppression due to the inhibition of alveolar macrophages and neutrophils by steroids, and receiving broad-spectrum antibiotics, play a role in the development of IPA in COPD patients. Colonized patients or those with IPA are older, with severe CODP stage (GOLD≥III), and have a higher number of comorbidities. The mortality rate is high due to the fact that having a definitive diagnosis of IPA in COPD patients is often difficult. The main clinical and radiological signs of IPA in these types of patients are non-specific, and tissue samples for definitive diagnosis are often difficult to obtain. The poor prognosis of IPA in COPD patients could perhaps be improved by faster diagnosis and prompt initiation of antifungal treatment. Some tools, such as scales and algorithms based on risk factors of IPA, may be useful for its early diagnosis in these patients.

The future of fungal susceptibility testing

ABSTRACT 

The antifungal treatment failures and the emergence of resistant fungal strains have stimulated the need for reproducible and clinically relevant antifungal susceptibility testing (AFST). While the standard reference methods are not intended for routine use, commercial methods are widely used for performing AFST. However, to accelerate AFST and to improve the detection of antifungal resistance, which is the most challenging goal of AFST, novel assays have been developed. Following brief drug exposures of fungal cells, the new antifungal susceptibility end points seem to provide a reliable means of identifying fungal isolates, which harbor mutations that have been associated with antifungal resistance. This article summarizes the recent progress in AFST that is destined to enhance its clinical utility in the near future.

A case of invasive pulmonary aspergillosis with direct invasion of the mediastinum and the left atrium in an immunocompetent patient

We report a case of invasive pulmonary aspergillosis invading the mediastinum and the left atrium. A 70-year-old woman was hospitalized for dyspnea. She had been well controlled for her diabetes mellitus and hypertension. The chest X-ray disclosed mediastinal widening, and the computed tomography scan of the chest showed that there was a large mediastinal mass and this lesion extended into the left atrium and right bronchus. The cardiac echocardiography showed that a huge mediastinal cystic mass compressed in the right atrium and a hyperechoic polypoid lesion in the left. The pathology from the bronchoscopic biopsy observed abundant fungal hyphae which was stained with periodic acid-Schiff and Gomori's methenamine silver. Despite the treatment with antifungal agents, she died from cardiac tamponade after three months. Invasive pulmonary aspergillosis, which involves the mediastinum and the heart, is very rare in immunocompetent patients.

Preliminary study of the fungal ecology at the haematology and medical-oncology ward in Bamako, Mali

Data on fungal epidemiology in sub-Saharan African countries are scarce. This exploratory study aimed to characterize the fungal flora at the Onco-Haematology ward of the National Teaching Hospital of Point G in Bamako, Mali. A cross-sectional survey was conducted in the dry and in the rainy seasons. Nasal swab and sputum samples were collected from the hospitalized patients while airborne fungal spores were collected using electrostatic dust-fall collectors. Fungi were identified by their morphological characteristics and MALDI-TOF mass spectrometry. Candida albicans was the most frequent yeast species colonizing patients; Aspergillus species were isolated in 86 % of the patients and were the main airborne environmental contaminants. Overall, airborne fungal contamination rates increased from 33.8 % in the dry to 66.2 % in the rainy season (p < 0.001). The most frequent Aspergillus species were Aspergillus niger (36.6 %) and Aspergillus flavus (32.92 %). In contrast, Aspergillus fumigatus (5.43 %) was relatively rare. This high level of fungal exposure raises concern regarding the management of at-risk patients in this Onco-Haematology ward and stresses the need for strengthening the mycological diagnostic capacities to accompany the implementation of adapted fungal infection prevention and management policies.

Susceptibility breakpoints for amphotericin B and Aspergillus species in an in vitro pharmacokinetic-pharmacodynamic model simulating free-drug concentrations in human serum

Although conventional amphotericin B was for many years the drug of choice and remains an important agent against invasive aspergillosis, reliable susceptibility breakpoints are lacking. Three clinical Aspergillus isolates (Aspergillus fumigatus, Aspergillus flavus, and Aspergillus terreus) were tested in an in vitro pharmacokinetic-pharmacodynamic model simulating the biphasic 24-h time-concentration profile of free amphotericin B concentrations in human serum with free peak concentrations (fCmax) of 0.1, 0.3, 0.6, 1.2, and 2.4 mg/liter administered once daily. Drug concentrations were measured with a bioassay, and fungal growth was monitored for 72 h with galactomannan production. The fCmax/MIC corresponding to half-maximal activity (P50) was determined for each species, and the percentage of target attainment was calculated for different MICs for the standard (1 mg/kg of body weight) and a lower (0.6-mg/kg) dose of amphotericin B with Monte Carlo simulation analysis. The fCmax/MICs (95% confidence intervals) corresponding to P50 were 0.145 (0.133 to 0.158), 0.371 (0.283 to 0.486), and 0.41 (0.292 to 0.522) for A. fumigatus, A. flavus, and A. terreus, respectively. The median percentages of P50 attainment were ≥88%, 47%, and 0% for A. fumigatus isolates with MICs of ≤0.5, 1, and ≥2 mg/liter, respectively, and ≥81%, 24%, and 0% and ≥75%, 15%, and 0% for A. flavus and A. terreus isolates with MICs of ≤0.25, 0.5, and ≥1 mg/liter, respectively. The lower dose of 0.6 mg/kg would retain efficacy for A. fumigatus, A. flavus, and A. terreus isolates with MICs of ≤0.25, ≤0.125, and ≤0.125 mg/liter, respectively. The susceptibility, intermediate susceptibility, and resistance breakpoints of ≤0.5, 1, and ≥2 mg/liter for A. fumigatus and ≤0.25, 0.5, and ≥1 mg/liter for A. flavus and A. terreus were determined for conventional amphotericin B with a pharmacokinetic-pharmacodynamic model simulating free-drug serum concentrations.

Discovery and development of first in class antifungal caspofungin (CANCIDAS®)--a case study

Covering: 1985 to 2001.This paper describes a fifteen year journey from concept to clinical discovery and development of the first in class caspofungin acetate (CANCIDAS®) a parenteral antifungal agent. Caspofungin is a semisynthetic derivative of pneumocandin B0, a naturally occurring, lipophilic cyclic peptide isolated from the fungus, Glarea lozoyensis. While the echinocandins had been previously studied for antifungal activity by several organizations, the class was dropped for a variety of reasons. Merck subsequently initiated a research program leading to the discovery and development of caspofungin. The multitude of challenges that ensued during the discovery and development process and which were successfully resolved by multi-disciplinary teams constitute the content of this article. The article consists of five sections that describe the discovery and development of caspofungin in chronological order: (i) discovery of the natural product pneumocandin B0 from fungal fermentations, (ii) fermentation development to improve the titer of pneumocandin B0 to make it commercially viable, (iii) semisynthetic modification by medicinal chemistry to successfully improve the properties of pneumocandin B0 leading to the discovery of caspofungin, (iv) development of commercial semisynthesis and purification and formulation development to improve stability and (v) clinical development and approval of CANCIDAS® as an antifungal drug which subsequently saved thousands of lives.

Anidulafungin: advantage for the newcomer?

Anidulafungin is the most recently approved compound of the echinocandin antifungal class. Its mode of action is the noncompetitive inhibition of β-(1,3)-D-glucan synthesis. Potent fungicidal activity has been demonstrated against many Candida spp., including non-albicansCandida spp. and fluconazole-resistant strains, as well as fungistatic activity against Aspergillus spp. Owing to low oral bioavailability, it can only be administered intravenously. Anidulafungin is not metabolized by the liver and renal clearance is negligible, thus rendering dosage adjustments in patients with impaired hepatic or renal function unnecessary. Due to lack of interference with the cytochrome P450 pathway, it displays minimal drug-drug interaction. Anidulafungin has been approved by the US FDA for the treatment of esophageal and invasive candidiasis after clinical trials demonstrated its noninferiority to fluconazole. In September 2007, anidulafungin gained EMEA approval for the treatment of invasive candidiasis in adult non-neutropenic patients. For those with invasive or noninvasive candidiasis with resistance or intolerance to fluconazole in particular, as well as those requiring antifungal medication, that anidulafungin does not interact with concomitant medication means it may be regarded as a safe and efficacious treatment option. Promising results from animal models and experience with the other echinocandins indicate several potential lines of investigation: invasive aspergillosis, prophylaxis and treatment of transplant patients, and empirical treatment in patients with febrile neutropenia. Significant differences in clinical efficacy or safety favoring anidulafungin over the other echinocandins are yet to be discovered.

Utilization and comparative effectiveness of caspofungin and voriconazole early after market approval in the U.S

Objectives

Both caspofungin and voriconazole were initially approved by the FDA with very narrow indications. Our aim was to evaluate the utilization patterns and comparative effectiveness of these agents early after marketing before any labeling change occurred.

Methods

This was a retrospective cohort study utilizing a large healthcare database in the United States. Patients who received at least one dose of systemic antifungal agent between the years 2001 and 2003 were included. Information was available for each hospital-day including underlying conditions, medications, procedures and disease severity scores. Tests for proportions, trend tests and logistic regression were used for evaluation of utilization. Propensity score analysis was used in comparison of mortality.

Results

The study cohort included 381,245 patients with serious underlying conditions. In just two years after marketing, caspofungin and voriconazole use increased to 40% of the total systemic antifungal consumption. However, only 3.4% of caspofungin and 12.5% of voriconazole were used as indicated in labeling. In the propensity score analyses, caspofungin was associated with 7% decrease in mortality (OR: 0.93 95% CI: 0.85–0.98). Voriconazole use was not found to be associated with mortality (OR: 1 . 95% CI: 0.89–1.12)

Conclusions

Caspofungin and voriconazole were mostly used of unapproved indications immediately after their marketing. Although unapproved drug use might be due to a crucial need by clinicians, this may create problems in further antifungal drug development. Our results suggest a survival benefit with caspofungin; however, similar comparative effectiveness studies must be repeated using more recent data.

Refractory invasive aspergillosis controlled with posaconazole and pulmonary surgery in a patient with chronic granulomatous disease: case report

Invasive aspergillosis is an important cause of morbidity and mortality in immunocompromised patients. Among primary immunodefiencies, chronic granulomatous disease (CGD) has the highest prevalence of invasive fungal diseases. Voriconazole is recommended for the primary treatment of invasive aspergillosis in most patients. In patients whose aspergillosis is refractory to voriconazole, therapeutic options include changing class of antifungal, for example using an amphotericin B formulation, an echinocandin, combination therapy, or further use of azoles. Posaconazole is a triazole derivative which is effective in Aspergillosis prophylaxis and treatment. Rarely, surgical therapy may be needed in some patients. Lesions those are contiguous with the great vessels or the pericardium, single cavitary lesion that cause hemoptysis, lesions invading the chest wall, aspergillosis that involves the skin and the bone are the indications for surgical therapy.Chronic granulomatous disease (CGD) is an inherited immundeficiency caused by defects in the phagocyte nicotinamide adenine dinucleotidephosphate (NADPH) oxidase complex which is mainstay of killing microorganisms. CGD is characterized by recurrent life-threatening bacterial and fungal infections and by abnormally exuberant inflammatory responses leading to granuloma formation, such as granulomatous enteritis, genitourinary obstruction, and wound dehiscence. The diagnosis is made by neutrophil function testing and the genotyping.Herein, we present a case with CGD who had invasive pulmonary aspergillosis refractory to voriconazole and liposomal amphotericine B combination therapy that was controlled with posaconazole treatment and pulmonary surgery.

Neutropenic fever and sepsis: evaluation and management

Neutropenia remains the predominant predisposing factor for infection in most cancer patients. Bacterial and fungal infections are common in this setting. Not all neutropenic patients have the same risk of developing severe infection or serious medical complications. Although all patients with neutropenia and fever should receive prompt, empiric antibiotic therapy, low-risk patients can be effectively managed without hospitalization-often with the administration of oral antibiotics. Other patients need hospital-based therapy. The emergence of resistant microorganisms has become a significant problem in neutropenic patients. Frequent epidemiologic surveys to detect the emergence of resistant organisms are recommended. Antibiotic stewardship and Infection Control Programs are important tools in combating resistant organisms.

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.

Incremental Healthcare Costs and Outpatient Antifungal Treatment of Patients with Aspergillosis in the United States

Objectives: To evaluate the total and outpatient economic burden of aspergillosis, and to describe the outpatient antifungal treatment of aspergillosis within a large, commercially-insured population in the United States. Methods: Adults with at least one medical claim with an aspergillosis diagnosis (International Classification of Disease 9th Revision Clinical Modification [ICD-9-CM] code 117.3 or 484.6) between 07/01/04-03/01/11 were identified from the MarketScan Research Databases. Patients had ≥6 months of pre-index and ≥1 month of post-index continuous health plan and pharmacy benefit enrollment and no pre-index diagnosis of aspergillosis. Aspergillosis cases were propensity score-matched to a sample of controls without aspergillosis. Outpatient antifungal therapy and total and outpatient healthcare resource utilization were evaluated in the post-index period. General linear models were used to estimate costs, which were adjusted by the length of follow-up. Incremental costs were calculated between cohorts and a bootstrap procedure was used to produce corresponding variation and 95% confidence interval estimates. Results: Aspergillosis cases (N=5,499; mean age: 57.8 years; 48.6% female; 64.2% with cancer) were matched to 5,499 controls (mean age: 58.3 years; 48.4% female; 60.6% with cancer). Two-thirds of the aspergillosis cases had no outpatient prescription for an antifungal within 30 days of index; for those with outpatient antifungal therapy, voriconazole was the most commonly prescribed agent (60.9%). Average adjusted total and outpatient expenditures were greater for aspergillosis patients during follow-up than those of the matched controls ($26,680 and $9,248 greater, respectively). Conclusions: The economic burden of aspergillosis is substantial. Patients with aspergillosis utilize significantly more healthcare resources and thus incur greater healthcare costs than do similar patients without aspergillosis.

Detection of invasive aspergillosis in bone marrow transplant recipients using real-time PCR

Objective:

The invasive aspergillosis (IA) is a serious opportunistic infection caused by various species of Aspergillus in immunocompromised individuals. Basically, rapid and early diagnosis prevents IA progression. In this study we performed a Real Time PCR/ Fluorescence Resonance Energy Transfer (FRET) for diagnosis of IA in hematologic malignancies and bone marrow transplant recipients.

Materials and Methods:

Sixty two patients with hematologic malignancies and marrow transplant recipients were evaluated for IA in Sari and Tehran from 2009 to 2010. The primer and hybridization probe were designed to amplify the specific sequence of 18S rRNA genes using Light Cycler system and FRET. Galactomannan (GM) assay was performed on serums which obtained from selected patients using the Platelia Aspergillus kit.

Results:

According to the criteria defined by the European Organization for Research and Treatment of Cancer and Mycoses Study Group (EORTC/MSG) for IA, 18 (29%) patients out of 62 patients were stratified into probable and possible groups. The female-to-male ratio was 1:2; the mean age of the patients was 36 years. The most common malignancies in these patients were acute lymphoblastic leukemia (38.9%). The minimum detection limit was 10 conidia (10¹ CFU/ml) equivalents (100 fg) per PCR reaction. GM assay was positive in 20.9% and real-time PCR probe set assay were positive in 17.7% patients who had clinical signs and host factor according to the mentioned criteria.

Conclusion:

Using the Real-Time PCR/FRET assay in whole blood specimens seems to be a promising method for diagnosis of IA, especially when used in combination with the GM detection test.

Cryptococcosis: epidemiology, fungal resistance, and new alternatives for treatment

Cryptococcosis is an important systemic mycosis and the third most prevalent disease in human immunodeficiency virus (HIV)-positive individuals. The incidence of cryptococcosis is high among the 25 million people with HIV/acquired immunodeficiency syndrome (AIDS), with recent estimates indicating that there are one million cases of cryptococcal meningitis globally per year in AIDS patients. In Cryptococcus neoformans, resistance to azoles may be associated with alterations in the target enzyme encoded by the gene ERG11, lanosterol 14α-demethylase. These alterations are obtained through mutations, or by overexpressing the gene encoding. In addition, C. gattii and C. neoformans present a heteroresistance phenotype, which may be related to increased virulence. Other species beyond C. neoformans and C. gattii, such as C. laurentii, have been diagnosed mainly in patients with immunosuppression. Infections of C. albidus have been isolated in cats and marine mammals. Recent evidence suggests that the majority of infections produced by this pathogen are associated with biofilm growth, which is also related with increased resistance to antifungal agents. Therefore, there is a great need to search for alternative antifungal agents for these fungi. The search for new molecules is currently occurring from nanoparticle drugs of plant peptide origin. This article presents a brief review of the literature regarding the epidemiology of cryptococcosis, as well as fungal resistance and new alternatives for treatment.

A Case of Acute Cerebral Aspergillosis Complicating Influenza A/H1N1pdm 2009

Invasive aspergillosis is a rare complication in patients with influenza infection. Several cases of invasive pulmonary aspergillosis accompanying influenza infections were reported during the influenza A/H1N1pdm 2009. We encountered a case of acute cerebral aspergillosis in a patient with influenza A/H1N1pdm 2009 infection. A 24-year-old man with uncontrolled diabetes was diagnosed with influenza A/H1N1pdm 2009 infection. Initial evaluation indicated methicillin-sensitive Staphylococcus aureus pneumonia and diabetic ketoacidosis along with influenza. During his hospital course, multiple new rim-enhancing mass lesions not evident in the initial evaluation developed in the fronto-parietal cortical and subcortical white matter and right cerebellum. Pathology and culture results confirmed the presence of Aspergillus fumigatus. Surgical drainage combined with a total of 18 weeks of antifungal therapy resulted in complete resolution of the infection. This case demonstrates that cerebral aspergillosis can present alongside influenza in patients with diabetes or those under intensive care. Clinical suspicion of invasive aspergillosis is required for a definite diagnosis and better prognosis in such cases.

Airway and parenchymal manifestations of pulmonary aspergillosis

Pulmonary aspergillosis encompasses a heterogeneous group of mycoses that result from either colonisation or pathogenic damage of lung tissue by Aspergillus fungi. These clinical entities range from relatively benign saprophytic hypersensitivity associated with fungal inhabitation to life threatening invasive disease. The diagnosis of pulmonary disorders related to Aspergillus is on the increase and it is more important than ever those both general and respiratory physicians have a good understanding of these disorders. This paper reviews the contemporary understanding of the clinical, radiographic and histopathological aspects of pulmonary aspergillosis.

Infection prevention in the cancer center

Cancer patients are frequently immunosuppressed and at risk for a wide range of opportunistic and healthcare-associated infections. A good infection prevention program is extremely important to reduce risk of infection. This review focuses on infection prevention measures specific to patients, healthcare personnel, and visitors in the cancer center.

Assessment of efficacy of antifungals against Aspergillus fumigatus: value of real-time bioluminescence imaging

Aspergillus fumigatus causes life-threatening infections, especially in immunocompromised patients. Common drugs for therapy of aspergillosis are polyenes, azoles, and echinocandins. However, despite in vitro efficacy of these antifungals, treatment failure is frequently observed. In this study, we established bioluminescence imaging to monitor drug efficacy under in vitro and in vivo conditions. In vitro assays confirmed the effectiveness of liposomal amphotericin B, voriconazole, and anidulafungin. Liposomal amphotericin B and voriconazole were fungicidal, whereas anidulafungin allowed initial germination of conidia that stopped elongation but allowed the conidia to remain viable. In vivo studies were performed with a leukopenic murine model. Mice were challenged by intranasal instillation with a bioluminescent reporter strain (5 × 10(5) and 2.5 × 10(5) conidia), and therapy efficacies of liposomal amphotericin B, voriconazole, and anidulafungin were monitored. For monotherapy, the highest treatment efficacy was observed with liposomal amphotericin B, whereas the efficacies of voriconazole and anidulafungin were strongly dependent on the infectious dose. When therapy efficacy was studied with different drug combinations, all combinations improved the rate of treatment success compared to that with monotherapy. One hundred percent survival was obtained for treatment with a combination of liposomal amphotericin B and anidulafungin, which prevented not only pulmonary infections but also infections of the sinus. In conclusion, combination therapy increases treatment success, at least in the murine infection model. In addition, our novel approach based on real-time imaging enables in vivo monitoring of drug efficacy in different organs during therapy of invasive aspergillosis.