Occurrence and kinetics of false-positive Aspergillus galactomannan test results following treatment with beta-lactam antibiotics in patients with hematological disorders

False-positive results of galactomannan assays in patients administered glucose-containing solutions

Galactomannan (GM) is a polysaccharide cell wall component released by Aspergillus spp., and an immunoenzymatic GM assay is used for the diagnosis of invasive pulmonary aspergillosis. We evaluated the cause of strong positivity for GM in patients with no typical signs of aspergillosis. Repeat assays were performed using different instruments and reagent lots, but there were no differences in results among the assays. Patients with strongly positive GM results were investigated. Medication histories revealed that 14 of 23 patients had been administered total parenteral nutrition solution from one manufacturer and 4 patients had been administered dextrose solution from a different manufacturer before being tested. The results of GM assays conducted on samples of dextrose solution and the glucose fraction of the total parenteral nutrition solution were strongly positive, confirming the causes of the false-positive reactions. We hypothesize that a trace amount of GM was introduced into the glucose-containing solutions because glucoamylase, which is necessary for the saccharification step of glucose synthesis, was derived from Aspergillus niger. To enhance patient care and prevent unnecessary antifungal prescriptions, healthcare providers and manufacturers of healthcare products need to be aware of the possibility of false-positive reactions for GM.

False-positive Aspergillus galactomannan immunoassay in the glucose component of total parenteral nutrition products

IMPORTANCE

This manuscript describes an occurrence of false-positive GM tests in patients receiving TPN products from a manufacturer who had recently changed the supplier of the glucose component. We describe the clinical presentation of nine false-positive cases and the results of serologic and microbiological investigations of the TPN products suspected of contamination with GM. Attempts to detect GM in parenteral nutrition products were made since the detection of GM in sodium gluconate-containing solutions in 2007, but none of them identified the source of elevated GM indexes in TPN products. However, the present study demonstrated that the glucose component of the TPN products contained a high level of GM antigen, which caused false-positive GM assay results. The source of GM was glucoamylase, which was derived from A. niger in the manufacturing process. Physicians and clinical microbiology laboratories should be aware of this issue to improve interpretation and patient care.

False positive Aspergillus galactomannan assay results caused by specific parenteral nutrition

In September 2022, the proportion of clinically false positive results with high index values for the galactomannan (GM) assay increased dramatically in our hospital and remained high until November 2022. We aimed to identify the possible causative agent that led to the dramatic increase in false positivity in GM assay. A case-control-control study was conducted, and patients admitted to two intensive care units between September and November 2022 were included. We defined each time point at which the GM assay was conducted in a patient as an episode and classified episodes into strong-positive (≥10.0 index; case), positive (control), and negative (<0.5 index; control) groups. We compared the medications administered in three groups and measured GM levels in relevant medications, including parenteral nutrition (PN). In total, 118 episodes in 33 patients were classified into three groups. There were 46 negative, 23 positive, and 49 strong-positive episodes, and there was a significant difference in the use of Winuf® PNs (P < .001) between the three groups. Forty episodes (82%) in the strong-positive group received Winuf®, compared with three (6.5%) in the negative group and one (4.3%) in the positive group (P < .001). All samples of Winuf® PNs used in the five patients whose GM results were repeatedly strong-positive were strongly positive for GM. False positivity in GM assay can be caused by the administration of specific PNs. A thorough investigation of prescribed medications should be considered when there is an abrupt increase in the proportion of strong-positive or positive GM results.

Invasive Aspergillosis in the Intensive Care Unit

Invasive pulmonary aspergillosis (IPA) is a serious condition resulting in significant mortality and morbidity among patients in intensive care units (ICUs). There is a growing number of at-risk patients for this condition with the increasing use of immunosuppressive therapies. The diagnosis of IPA can be difficult in ICUs, and relies on integration of clinical, radiological, and microbiological features. In this review, we discuss patient populations at risk for IPA, as well as the diagnostic criteria employed. We review the fungal biomarkers used, as well as the challenges in distinguishing colonization with Aspergillus from invasive disease. We also address the growing concern of multidrug-resistant Aspergillosis and review the new and novel therapeutics which are in development to combat this.

Association of Tocilizumab and Invasive Aspergillosis in Critically Ill Patients with Severe COVID-19 Pneumonia and Acute Respiratory Distress Syndrome

Coronavirus disease-2019 (COVID-19) causes severe pneumonia and acute respiratory distress syndrome. According to the current consensus, immunosuppressants, such as dexamethasone and anti-interleukin-6 receptor monoclonal antibodies, are therapeutic medications in the early stages of infection. However, in critically ill patients, viral, fungal, and bacterial coinfection results in higher mortality. We conducted a single-center, retrospective analysis of 29 mechanically ventilated patients with artificial airways. Patients were adults with confirmed COVID-19 infection and severe pneumonia. Acute respiratory distress syndrome was diagnosed according to the Kigali modification of the Berlin definition. Six patients had invasive pulmonary aspergillosis coinfection based on elevated serum galactomannan levels and/or bronchoalveolar lavage fluid. We present two cases with brief histories and available clinical data. We also conducted a literature review to determine whether immunosuppressants, such as tocilizumab, increase infection risk or invasive aspergillosis in patients with COVID-19. There is no conclusive evidence to suggest that tocilizumab increases coinfection risk. However, further studies are needed to determine the optimal dose, between-dose interval, and timing of tocilizumab administration in patients with COVID-19.

Challenges with Utilizing the 1,3-Beta-d-Glucan and Galactomannan Assays To Diagnose Invasive Mold Infections in Immunocompromised Children

Establishing the diagnosis of invasive mold infections (IMI) in immunocompromised children is challenging due to nonspecific clinical presentations and the limited sensitivity of traditional culture-based methods. Rapid non-culture-based diagnostics such as the 1,3-beta-d-glucan and galactomannan assays have emerged as promising adjuncts to conventional diagnostic tests in adults. Available data suggest that 1,3-beta-d-glucan has limited accuracy in the pediatric population and is not recommended to be used for the diagnosis of IMI in children. On the other hand, the diagnostic performance of the serum and bronchoalveolar lavage galactomannan in immunocompromised children is comparable to results observed in adults and can be used as a screening tool in children at high risk of developing invasive aspergillosis (IA) who are not receiving mold-active antifungal prophylaxis and as a diagnostic tool in symptomatic children suspected of having IA. Herein, we summarize the available evidence for the use of these rapid non-culture-based diagnostics in immunocompromised children. We also summarize potential causes of false positivity for the 1,3-beta-d-glucan and galactomannan assays.

Co-infections, secondary infections, and antimicrobial use in patients hospitalised with COVID-19 during the first pandemic wave from the ISARIC WHO CCP-UK study: a multicentre, prospective cohort study

BACKGROUND

Microbiological characterisation of co-infections and secondary infections in patients with COVID-19 is lacking, and antimicrobial use is high. We aimed to describe microbiologically confirmed co-infections and secondary infections, and antimicrobial use, in patients admitted to hospital with COVID-19.

METHODS

The International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) WHO Clinical Characterisation Protocol UK (CCP-UK) study is an ongoing, prospective cohort study recruiting inpatients from 260 hospitals in England, Scotland, and Wales, conducted by the ISARIC Coronavirus Clinical Characterisation Consortium. Patients with a confirmed or clinician-defined high likelihood of SARS-CoV-2 infection were eligible for inclusion in the ISARIC WHO CCP-UK study. For this specific study, we excluded patients with a recorded negative SARS-CoV-2 test result and those without a recorded outcome at 28 days after admission. Demographic, clinical, laboratory, therapeutic, and outcome data were collected using a prespecified case report form. Organisms considered clinically insignificant were excluded.

FINDINGS

We analysed data from 48 902 patients admitted to hospital between Feb 6 and June 8, 2020. The median patient age was 74 years (IQR 59-84) and 20 786 (42·6%) of 48 765 patients were female. Microbiological investigations were recorded for 8649 (17·7%) of 48 902 patients, with clinically significant COVID-19-related respiratory or bloodstream culture results recorded for 1107 patients. 762 (70·6%) of 1080 infections were secondary, occurring more than 2 days after hospital admission. Staphylococcus aureus and Haemophilus influenzae were the most common pathogens causing respiratory co-infections (diagnosed ≤2 days after admission), with Enterobacteriaceae and S aureus most common in secondary respiratory infections. Bloodstream infections were most frequently caused by Escherichia coli and S aureus. Among patients with available data, 13 390 (37·0%) of 36 145 had received antimicrobials in the community for this illness episode before hospital admission and 39 258 (85·2%) of 46 061 patients with inpatient antimicrobial data received one or more antimicrobials at some point during their admission (highest for patients in critical care). We identified frequent use of broad-spectrum agents and use of carbapenems rather than carbapenem-sparing alternatives.

INTERPRETATION

In patients admitted to hospital with COVID-19, microbiologically confirmed bacterial infections are rare, and more likely to be secondary infections. Gram-negative organisms and S aureus are the predominant pathogens. The frequency and nature of antimicrobial use are concerning, but tractable targets for stewardship interventions exist.

FUNDING

National Institute for Health Research (NIHR), UK Medical Research Council, Wellcome Trust, UK Department for International Development, Bill & Melinda Gates Foundation, EU Platform for European Preparedness Against (Re-)emerging Epidemics, NIHR Health Protection Research Unit (HPRU) in Emerging and Zoonotic Infections at University of Liverpool, and NIHR HPRU in Respiratory Infections at Imperial College London.

Diagnostic yield of a bronchoalveolar lavage fluid galactomannan assay in patients with negative serum galactomannan results suspected to have invasive pulmonary aspergillosis

BACKGROUND AND OBJECTIVES

There are limited data in real clinical practice on the diagnostic value of a bronchoalveolar lavage (BAL) fluid galactomannan (GM) assay in patients with suspected invasive pulmonary aspergillosis (IPA) who had negative serum GM results. Thus, we investigated the diagnostic performance of a BAL GM assay in patients with negative serum GM assay results who were suspected to have IPA.

METHODS

This retrospective study was performed between May 2008 and April 2019 at a tertiary-care hospital in Seoul, South Korea. All patients with suspected IPA whose serum GM assays revealed negative results who sequentially underwent BAL were enrolled in this study.

RESULTS

A total of 341 patients with suspected IPA including four cases of proven IPA, 38 cases of probable IPA, 107 cases of possible IPA and 192 patients without IPA were enrolled. Of these 341 patients, 107 (31%) with possible IPA were excluded from the final analysis. Of 42 patients with proven and probable IPA who had initial negative serum GM results, 24 (57%) had positive BAL GM results (n = 24) or BAL fungal culture results (n = 8). In addition, BAL revealed evidence of other opportunistic infections including Pneumocystis jirovecii pneumonia (14% [26/190]), cytomegalovirus (CMV) pneumonia (5% [9/188]) and respiratory viral pneumonia (6% [12/193]).

CONCLUSION

Sequential BAL in patients with suspected IPA who had initial negative serum GM results provided additional diagnostic yield in approximately half of patients with evidence of another co-infection.

Defining Galactomannan Positivity in the Updated EORTC/MSGERC Consensus Definitions of Invasive Fungal Diseases

The consensus definitions of invasive fungal diseases from the EORTC/MSGERC were recently revised and updated. They now include consensus cutoff values for the galactomannan test that support the diagnosis of probable invasive aspergillosis. In this supplement article, we provide a rationale for these proposed thresholds based on the test's characteristics and performance in different patient populations and in different specimen types.

Effect of an oral probiotic nutraceutical containing Aspergillus-derived ingredients on a serum and urine galactomannan antigen assay in dogs

A commercial Aspergillus galactomannan antigen (GMA) enzyme linked immunosorbent assay (ELISA) is used to support a diagnosis of systemic aspergillosis in dogs. In human patients, false positive results have been associated with administration of medications derived from molds. We sought to determine the effect of administration of a commercially available oral probiotic nutraceutical that contained Aspergillus-derived ingredients on serum and urine Aspergillus GMA levels in dogs by conducting a prospective, cross-over study. Galactomannan index (GMI) was measured on the solubilized probiotic nutraceutical and was positive (GMI ≥ 0.5) with a mean of 7.91. Serum and urine galactomannan indices were measured in 10 healthy dogs before (day 0) and after 1 week (day 7) of probiotic nutraceutical administration, then again 2 weeks after the probiotic nutraceutical was discontinued (day 21). Median (range) serum GMI were 0.19 (0.08-0.62), 0.22 (0.07-1.15) and 0.17 (0.14-0.63) at day 0, 7 and 21, respectively. Two of 10 dogs developed positive GMI (≥0.5) results after probiotic nutraceutical administration; however, no significant changes were noted over the study period. Median (range) urine GMI results were 0.06 (0.04-0.22), 0.07 (0.05-0.41) and 0.06 (0.03-0.16) at day 0, 7 and 21, respectively. A trend towards an increase urine GMI was noted between day 0 and 7 (P = 0.18), and decrease was noted between day 7 and 21 (P = 0.09). Administration of probiotics containing Aspergillus-derived ingredients to dogs did not reliably result in elevated Aspergillus GMA levels.

Digestive enzymes of fungal origin as a relevant cause of false positive Aspergillus antigen testing in intensive care unit patients

Background

Galactomannan antigen (GM) testing is widely used in the diagnosis of invasive aspergillosis (IA). Digestive enzymes play an important role in enzyme substitution therapy in exocrine pancreatic insufficiency. As digestive enzymes of fungal origin like Nortase contain enzymes from Aspergillus, a false-positive result of the test might be possible because of cross-reacting antigens of the cell wall of the producing fungi. We, therefore, asked whether the administration of fungal enzymes is a relevant cause of false-positive GM antigen test results.

Methods

Patients with a positive GM antigen test between January 2016 and April 2020 were included in the evaluation and divided into two groups: group 1—Nortase-therapy, group 2—no Nortase-therapy. In addition, dissolved Nortase samples were analyzed in vitro for GM and β-1,3-D-glucan. For statistical analysis, the chi-squared and Mann‒Whitney U tests were used.

Results

Sixty-five patients were included in this evaluation (30 patients receiving Nortase and 35 patients not receiving Nortase). The overall false positivity rate of GM testing was 43.1%. Notably, false-positive results were detected significantly more often in the Nortase group (73.3%) than in the control group (17.1%, p < 0.001). While the positive predictive value of GM testing was 0.83 in the control group, there was a dramatic decline to 0.27 in the Nortase group. In vitro analysis proved that the Nortase enzyme preparation was highly positive for the fungal antigens GM and β-1,3-D-glucan.

Conclusions

Our data demonstrate that the administration of digestive enzymes of fungal origin like Nortase leads to a significantly higher rate of false-positive GM test results compared to that in patients without digestive enzyme treatment.

Genetic Risk Surveillance for Invasive Aspergillosis in Hematology Patients: A Prospective Observational Study

INTRODUCTION

The association between genetic background and the risk of invasive aspergillosis (IA) has not been addressed in Thailand. We conducted genetic risk surveillance for IA among Thai hematologic patients.

METHODS

We conducted a prospective observational cohort study including moderate- to high-risk hematology patients at Ramathibodi Hospital. IA occurrence, relevant clinical data, and genetic analyses were assessed. Odds ratios (ORs) of IA were assessed for the presence of the selected single nucleotide polymorphism genotype using logistic regression.

RESULTS

A total of 357 patients were enrolled. The most common hematologic disease was non-Hodgkin lymphoma (45.1%). IA was diagnosed in 36 patients (10.10%). The C allele of IL10_rs1800896 was associated with an increased risk of IA (adjusted OR 5.297; 95% confidence interval [CI] 2.032-13.809, p = 0.001). In multivariate Cox regression analysis, prolonged neutropenia and the C allele of IL10_rs1800896 were associated with IA (hazard ratio [HR] 12.585; 95% CI 3.866-40.967, p < 0.001 and HR 2.449; 95% CI 1.097-5.468, p = 0.042, respectively).

CONCLUSIONS

Carrying the C allele of IL10_rs1800896 was associated with an increased risk of IA among moderate- to high-risk Thai patients with hematologic diseases. This finding can potentially lead to a novel risk stratification scheme to further prevent IA in resource-limited settings.

Work-up for Fever During Neutropenia for Both the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient

Fever is a common complication in patients with underlying neutropenia and is associated with significant mortality in neutropenic patients with acute myelogenous leukemia or hematopoietic cell transplant. Fever may be the only sign of infection and requires further clinical assessment, including a history, a physical examination, and additional laboratory and radiographic testing. National and international guidelines recommend initiation of empiric antimicrobial therapy in patients with fever during neutropenia. Stepwise escalation of antibacterial therapy, followed by antifungal therapy for patients with persistent fever, generally is recommended. Consideration should also be given to de-escalation of antimicrobial therapy in the appropriate clinical settings.

Monoclonal Antibody AP3 Binds Galactomannan Antigens Displayed by the Pathogens Aspergillus flavus, A. fumigatus, and A. parasiticus

Aspergillus fumigatus and A. flavus are the fungal pathogens responsible for most cases of invasive aspergillosis (IA). Early detection of the circulating antigen galactomannan (GM) in serum allows the prompt application of effective antifungal therapy, thus improving the survival rate of IA patients. However, the use of monoclonal antibodies (mAbs) for the diagnosis of IA is often associated with false positives due to cross-reaction with bacterial polysaccharides. More specific antibodies are therefore needed. Here we describe the characterization of the Aspergillus-specific mAb AP3 (IgG1κ), including the precise identification of its corresponding antigen. The antibody was generated using A. parasiticus cell wall fragments and was shown to bind several Aspergillus species. Immunofluorescence microscopy revealed that AP3 binds a cell wall antigen, but immunoprecipitation and enzyme-linked immunosorbent assays showed that the antigen is also secreted into the culture medium. The inability of AP3 to bind the A. fumigatus galactofuranose (Galf )-deficient mutant ΔglfA confirmed that Galf residues are part of the epitope. Several lines of evidence strongly indicated that AP3 recognizes the Galf residues of O-linked glycans on Aspergillus proteins. Glycoarray analysis revealed that AP3 recognizes oligo-[β-D-Galf-1,5] sequences containing four or more residues with longer chains more efficiently. We also showed that AP3 captures GM in serum, suggesting it may be useful as a diagnostic tool for patients with IA.

False-positive Candida and Aspergillus antigen testing in recipients of allogeneic haematopoietic cell transplantation due to administration of parenteral nutrition and fixed combinations of piperacillin-tazobactam

False positivity of antigen immunoassays used as an early diagnostic tool to detect invasive fungal infections is known. Interpretation of the assay needs the identification of sources which could affect the specificity of the test. We focused on the influence of parenteral nutrition (PN) and piperacillin-tazobactam (TZP) on fungal immunoassays. Measurable amounts of Candida antigen mannan were detected in several compounds of PN and TZP in a previous in vitro study. In the current study, 84 patients undergoing allogeneic haematopoietic cell transplantation receiving either TZP, PN or both were monitored with Aspergillus and Candida antigen assay. Six patients were analysed closer in a kinetic analysis with more frequent blood sampling to detect mannan. PN in diverse compositions as well as TZP did not increase significantly the amount of mannan and the Aspergillus antigen in serum. We could not confirm the positive results of the in vitro study. Physicians should be aware that mannan antigenemia due to drug infusion could be a transient issue and should be considered in the interpretation of fungal immunoassays, although we could not find clinically relevant effects on mannan levels.

Comparing the profile of respiratory fungal pathogens amongst immunocompetent and immunocompromised hosts, their susceptibility pattern and correlation of various opportunistic respiratory fungal infections and their progression in relation to the CD4+T-cell counts

Introduction

Invasive fungal infections are increasingly common in the nosocomial setting.

Materials and Methods

The patients were divided into two groups immunocompetent and immunocompromised that is, patients with significant neutropenia <500 neutrophils/μl for longer than 10 days. microscopy, culture, identification of isolates were done and some specilised tests on serum and BAL for antigen detection were performed.

Results

Majority of the patients were young adult males in this study. A higher prevalence of 26.7% was seen in immunocompromised patients. Amongst yeasts, Candida albicans was the predominant species followed by the National AIDS Control that is, Candida glabrata, Candida dubliniensis, Candida parapsilosis and Candida tropicalis in the same order. Amongst moulds, Aspergillus fumigatus was the most common species followed by Aspergillus flavus and Aspergillus niger. Mucor and Penicillium marneffei were seen in a lower prevalence. By Broth microdilution method, isolates of Candida spp. were most sensitive to caspofungin, amphotericin B, ketoconazole and fluconazole in the same order. Isolates of Aspergillus spp. were most sensitive to caspofungin, amphotericin B and itraconazole in the same order. By disc diffusion method, resistance to fluconazole was observed in 6.9% isolates of C. albicans. 50% of C. dubliniensis and 20% of C. glabrata showed resistance to fluconazole. A total mortality of 27.7% was observed during this study. This was distributed as 24.1%, 26.7%, 50%, 50%, 100% and 0% among by patients of candidiasis, aspergillosis, cryptococcosis, pneumocystosis, mucormycosis and penicilliosis. Fifteen per cent were lost to follow-up.

Conclusion

Patterns of invasive fungal infections are changing in many ways. In the midst of these evolving trends, IFI of the respiratory tractcontinue to remain important causes of morbidity and mortality. Diagnostic tools can be adequately used only if the treating physician is aware of the propensity of patients to acquire a fungal infection. Thus, continuous awareness and education is crucial for successful management of patients. Judicious use of antifungal medications as prophylactic measures must be employed, particularly in the critically ill and patients of HIV.

Current State of the Diagnosis of Invasive Pulmonary Aspergillosis in Lung Transplantation

As the number of lung transplants performed worldwide each year continues to grow, the success of this procedure is threatened by the incidence of non-CMV infections such as invasive aspergillosis. Despite tremendous efforts and the availability of numerous diagnostic tests (especially in hematological malignancies) the diagnosis of invasive aspergillosis continues to be a challenge. Lung transplantation remains a unique clinical scenario, where additional host defenses are immunocompromized, making many of the available tests unsuitable. In this review we will navigate through the myriad of diagnostic tests currently available and how they apply to this unique patient population, as well as have a look into what the future holds.

Invasive Aspergillosis in Children: Update on Current Guidelines

Invasive aspergillosis (IA) is an important cause of infectious morbidity and mortality in immunocompromised paediatric patients. Despite improvements in diagnosis, prevention, and treatment, IA is still associated with high mortality rates. To address this issue, several international societies and organisations have proposed guidelines for the management of IA in the paediatric population. In this article, we review current recommendations of the Infectious Diseases Society of America, the European Conference on Infection in Leukaemia and the European Society of Clinical Microbiology and Infectious Diseases for the management and prevention of IA in children.

Assessing the risk of false positive serum galactomannan among patients receiving piperacillin/tazobactam for febrile neutropenia

Galactomannan (GM) assay is commonly used as an early diagnostic tool for invasive fungal infection (IFI) in high-risk hematology patients. False positivity is frequently observed in GM with the use of piperacillin/tazobactam. The usage of generic drugs over the original brand has a significant cost advantage. The aim of this study was to assess the performance of GM test among patients receiving original and generic piperacillin/tazobactam formulations. The study included 85 adult patients; 62.4% were male with hematological malignancy currently receiving piperacillin/tazobactam. The study group was divided into two groups: patients receiving original and generic piperacillin/tazobactam. Serum GM index was positive in one of 35 patients receiving original piperacillin/tazobactam, whereas it was positive in 46 out of 50 patients receiving generic piperacillin/tazobactam (P < .001). However, the patients receiving generic piperacillin/tazobactam underwent computed tomography (CT) scans more frequently than those receiving original piperacillin/tazobactam (P = .047). In addition, in vitro analysis of GM was performed in two generics and one original piperacillin/tazobactam vials. One generic piperacillin/tazobactam vial included high GM level. False positivity of serum GM with generic formulations of piperacillin/tazobactam is still an ongoing issue in hematology patients. A high rate of serum GM index false positivity may unexpectedly lead to a higher rate of CT scan. Selected piperacillin/tazobactam vials in each batch should be checked for GM to identify a false positivity of GM before purchase.

Sputum signatures for invasive pulmonary aspergillosis in patients with underlying respiratory diseases (SPARED): study protocol for a prospective diagnostic trial

BACKGROUND

Invasive pulmonary aspergillosis (IPA) has been increasingly reported in patients with underlying respiratory diseases (URD). Early diagnosis of IPA is crucial for mortality reduction and improved prognosis, yet remains difficult. Existing diagnostic tools for IPA largely rely on the detection of biomarkers based on serum or bronchoalveolar lavage fluid (BALF), both of which have their limitations. The use of sputum sample is non-invasive, and Aspergillus detection is feasible; however, the usefulness of sputum biomarkers for the diagnosis of IPA, especially in patients with URD, has not been systematically studied.

METHODS

This is a prospective diagnostic trial. At least 118 participants will be recruited from respiratory wards and intensive care units. IPA is defined according to the EORTC/MSG criteria modified for patients with URD. Induced sputum and blood will be collected, and BALF will be obtained by bronchoscopy. Sputum biomarkers, including galactomannan, Aspergillus DNA, triacetylfusarinine and bis(methylthio)gliotoxin will be determined, and the presence of a JF5 antigen will be examined with a lateral fluid device. The sensitivity, specificity, negative predictive value, positive predictive value and diagnostic odds ratio will be computed for different biomarkers and compared using the McNemar χ2 test. Receiver operating characteristic analyses will be performed, and the cut-off values will be established. Participants will receive follow-up evaluations at 3 months and 6 months after recruitment. The difference in hospital stay and survival will be analysed, and the relationships between the levels of biomarkers and hospital stay and survival will be analysed via regression models.

DISCUSSION

We have developed and verified the feasibility of Aspergillus-related biomarker assays for sputum. The study findings will contribute to a novel look at the diagnostic performance of sputum biomarkers in IPA and provide important insight into the improvement of the early diagnosis of IPA, particularly in patients with URD.

TRIAL REGISTRATION

This study has been registered with the Chinese Clinical Trial Registry ( ChiCTR-DPD-16009070 ) on 24th of August 2016.

Use of Galactomannan Antigen and Aspergillus DNA Real-time Polymerase Chain Reaction as Routine Methods for Invasive Aspergillosis in Immunosuppressed Children in Greece

PURPOSE

Invasive aspergillosis (IA) remains a critical issue in immunosuppressed patients. Detection of galactomannan antigen (GM) in serum samples is included as a criterion of IA by the European Organization for the Research and Treatment of Cancer/Mycoses Study Group. Nevertheless, Aspergillus DNA detection by polymerase chain reaction (PCR) has not yet been included because clinical data validation is lacking. The present study describes the simultaneous performance of GM and PCR tests as routine methods for IA diagnosis.

METHODS

During the period January 2012 to December 2017, a total of 156 white children hospitalized in a tertiary children's hospital of Athens (97 boys and 59 girls; age range, 5 months-14 years) were examined as possible cases of IA. Patients were classified into 4 groups based on their underlying diseases: hematologic malignancies (107 of 156 [68.6%]), solid tumors (16 of 156 [10.2%]), primary immunodeficiency (12 of 156 [7.7%]), and hereditary immunodeficiency (21 of 156 [13.5%]). GM detection was made with the Platelia Aspergillus Ag kit (Bio-Rad Laboratories, Hercules, California). Sera with a cut-off index ≥0.5 on at least 2 separate blood collections were considered positive. Serum detection of Aspergillus DNA was conducted with real-time PCR MycAssay Aspergillus assay (Myconostica Ltd, Cambridge, United Kingdom). PCR positivity was determined by using a threshold of 38 cycles in at least 1 serum sample. Four or more successive samples per patient were tested.

FINDINGS

Overall, 28 of 156 patients (53 of 744 serum samples) were found positive. Eleven patients were positive using both methods (24 samples). Four children were positive only by PCR (6 samples), whereas 13 (23 samples) were positive only with GM in consecutive samples. Agreement of both methods, GM(+)/PCR(+) or GM(-)/PCR(-), was found in 139 patients (90% of total patients) and 715 samples (96.1% of total samples). The agreement of both methods was found: (1) 85% in patients with hematologic malignancies; (2) 100% in patients with solid tumors; (3) 97.5% in patients with primary immunodeficiency; and (4) 98.8% in patients with hereditary immunodeficiency. Overall disagreement was observed in 17 patients, in which the positive result in any of the 2 methods was estimated as true positive in conjunction with radiologic and other clinical findings.

IMPLICATIONS

The combination of GM and PCR, provided high diagnostic accuracy in consecutive samples (twice a week). Clinical, radiologic, and other laboratory findings should be taken into consideration in the evaluation of GM and PCR.

Serum galactomannan antigen as a prognostic and diagnostic marker for invasive aspergillosis in heterogeneous medicine ICU patient population

Objective

This study was conducted to get a complete clinical and mycological picture of invasive aspergillosis (IA) in respiratory medicine ICU of a tertiary care hospital.

Patients

From the cohort of 235 patients only one had proven IA. Based on AspICU algorithm, 21 had putative IA (8.9%), 12 were colonised (5.1%).

Results

Adjusting the confounding factors, significant risk factors for IA were chronic obstructive pulmonary disease (COPD), temperature of ≥38°C, pneumonia and acute respiratory distress syndrome (ARDS). The best predictor of IA was AspICU algorithm (AUC, 1) followed by serum galactomannan antigen (GM) cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.822). For 37% of patients, IA diagnoses was made earlier with serum GM than radiology. There were 70/235 (29.8%) deaths within 30 days of enrolment in the study. Aspergillus culture positivity (34/235, 14.5%) was associated with very high mortality (27/34, 79.4%), (p<0.05). The best predictor of mortality was GM cut-off (≥1.24) calculated based on AspICU algorithm (AUC, 0.835).

Conclusion

This study imparts the focus on relatively underestimated Aspergillus infections prevalent in ICUs. The AspICU algorithm was found to be useful over others for IA diagnosis. The prognostic usefulness of serum GM antigen detection test highlighted overlooking the same may not be rewarding for the outcome of IA suspected ICU subpopulation.

Galactomannan, a Surrogate Marker for Outcome in Invasive Aspergillosis: Finally Coming of Age

Detection of galactomannan has become widely available for diagnosing invasive aspergillosis. The test characteristics, using the Platelia™ enzyme-immunoassay, have been well described. This assay could potentially also be useful for the early evaluation of the efficacy of antifungal therapy and for predicting the outcome in terms of response and survival. In this systematic review, we assessed the available evidence for the use of serum galactomannan at baseline as a prognostic marker, and the predictive value of serum galactomannan kinetics after initiation of antifungal therapy. Overall, serum galactomannan at baseline and galactomannan kinetics appear to be good predictors of therapy response and survival. However, breakpoints for predicting therapy failure and validation in different patient populations are still lacking.

Novel mouse monoclonal antibodies specifically recognize Aspergillus fumigatus galactomannan

A panel of specific monoclonal antibodies (mAbs) against synthetic pentasaccharide β-D-Galf-(1→5)-[β-D-Galf-(1→5)]₃-α-D-Manp, structurally related to Aspergillus fumigatus galactomannan, was generated using mice immunized with synthetic pentasaccharide-BSA conjugate and by hybridoma technology. Two selected mAbs, 7B8 and 8G4, could bind with the initial pentasaccharide with affinity constants of approximately 5.3 nM and 6.4 nM, respectively, based on surface plasmon resonance-based biosensor assay. The glycoarray, built from a series of synthetic oligosaccharide derivatives representing different galactomannan fragments, demonstrated that mAb 8G4 could effectively recognize the parental pentasaccharide while mAb 7B8 recognizes its constituting trisaccharide parts. Immunofluorescence studies showed that both 7B8 and 8G4 could stain A. fumigatus cells in culture efficiently, but not the mutant strain lacking galactomannan. In addition, confocal microscopy demonstrated that Candida albicans, Bifidobacterium longum, Lactobacillus plantarum, and numerous gram-positive and gram-negative bacteria were not labeled by mAbs 7B8 and 8G4. The generated mAbs can be considered promising for the development of a new specific enzyme-linked assay for detection of A. fumigatus, which is highly demanded for medical and environmental controls.

[Invasive pulmonary aspergillosis]

INTRODUCTION

Invasive pulmonary aspergillosis (IPA) is an important cause of morbidity and mortality in a wide range of patients. Early recognition and diagnosis have become a major focus in improving the management and outcomes of this life-threatening disease.

BACKGROUND

IPA typically occurs during a period of severe and prolonged neutropenia. However, solid organ transplant recipients, patients under immunosuppressive therapy or hospitalized in intensive care units are also at risk. The diagnosis is suspected in the presence of a combination of clinical, biological and CT scan evidence. The microbiological diagnostic strategy should be adapted to the patient's profile. Conventional methods with culture and species identification remain the standard but early diagnosis has been improved by the use of biomarkers such as galactomannan antigen in serum or in bronchoalveolar lavage.

OUTLOOK

The epidemiology of IPA should change with the increased use of antifungal prophylactic regimens and the arrival of targeted therapies. Other microbiological tools, such as PCR and other biomarkers, are currently being assessed.

CONCLUSIONS

IPA must be considered in a wide range of patients. Its prognosis remains poor despite progress in the microbiological diagnosis and therapeutic management.

The limited role of serum galactomannan assay in screening for invasive pulmonary aspergillosis in allogeneic stem cell transplantation recipients on micafungin prophylaxis: a retrospective study

Background

We evaluated the outcomes of serum galactomannan (GM) assay for the screening of invasive pulmonary aspergillosis (IPA) in allogeneic hematopoietic stem cell transplantation (alloHSCT) recipients while on primary antifungal prophylaxis (PAP).

Methods

This study included patients with hematologic disorders who underwent alloHSCT from January 2013 to November 2015. Patients received routine PAP with fluconazole before 2014 and micafungin after 2014; serum GM tests were performed and retrospectively analyzed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of serum GM tests for detection of probable/proven IPA were evaluated. The serial change of serum GM levels was illustrated on a time series plot.

Results

A total of 136 alloHSCT recipients at Seoul National University Hospital were included in the study. Fluconazole was administered in 72 patients for PAP, while micafungin was administered in the remaining 64 patients. The overall sensitivity, specificity, and NPV of serum GM assays were 95.8% (95% confidence interval [CI] 78.9–99.9%), 93.8% (95% CI 91.7–95.5%), and 99.8% (95% CI 99.1–100.0%), respectively. However, the PPV of GM tests was relatively low at 35.4% (95% CI 23.9–48.2%). The serial change in serum GM levels differed according to the antifungal agents used. With effective PAP using micafungin, serial serum GM levels showed zero order kinetics during the neutropenic period.

Conclusion

Although the serum GM assay is a sensitive and specific test for detecting IPA in alloHSCT recipients, its role for routine surveillance in an era of effective PAP with micafungin is limited.

Pulmonary aspergillosis as opportunistic mycoses in a cohort of human immunodeficiency virus-infected patients: Report from a tertiary care hospital in North India

OBJECTIVE

The incidence of pulmonary aspergillosis in human immunodeficiency virus (HIV)-infected persons is rising. This study was designed to determine the prevalence of pulmonary aspergillosis in a cohort of HIV-positive patients (n = 71) presenting with lower respiratory tract infection at a tertiary care medical center in India.

METHODS

Sputum samples were collected, and potassium hydroxide mount, cultural characteristics, and lactophenol cotton blue preparations were employed to aid in the identification of Aspergillus species. In addition, serum galactomannan antigen testing was also performed.

RESULTS

Pulmonary aspergillosis was diagnosed in 7 patients, five of whom showed a positive antigenemia indicating invasive form of disease. The prevalence of pulmonary aspergillosis was highest in individuals 21-40 years of age (13.3%). The gender-wise prevalence of pulmonary aspergillosis was 18.7% and 7.7% in females and males, respectively. The common chest radiographic findings noted in patients with pulmonary aspergillosis included a normal chest radiograph in 3 (42.8%), infiltrates in 2 (28.6%), and pleural effusion in 2 (28.6%). The common Aspergillus species recovered from sputa of these patients were Aspergillus flavus (4; 57.1%); Aspergillus fumigatus (2; 28.6%), and Aspergillus niger (1; 14.3%). A predisposing lung condition in the form of pulmonary tuberculosis was identified in 2; Pneumocystis carinii pneumonia in 2 and a dual tubercular and P. carinii infection in one. The mean CD4 count of these patients was 155.86 ± 119.33 cells/µl (median = 117 cells/µl; range = 18-329 cells/µl).

CONCLUSION

Our findings suggest that Aspergillus species be considered possible etiological agents in HIV-positive patients with pulmonary infection.

Invasive pulmonary mycosis due to Chaetomium globosum with false-positive galactomannan test: a case report and literature review

In this case, the authors report Chaetomium globosum as a cause of invasive pulmonary infection in a patient with Wegener's granulomatosis. Fungal hyphae (KOH and Calcofluor) were seen on direct microscopy of lung biopsy sample and bronchoalveolar lavage (BAL) sample. C. globosum isolated on culture clinched the diagnosis of invasive pulmonary infection by Chaetomium spp. A positive galactomannan of serum and BAL was repeatedly seen and was utilised for follow-up and as prognostic marker in patient management. The patient was successfully treated with liposomal amphotericin B followed by voriconazole. All the Chaetomium infections reported till date since 1980 are reviewed. Chaetomium spp. with its unique ecology has a hidden clinical potential to cause invasive mould infections.

Multiple myeloma as a major cause of false-positive galactomannan tests in adult patients with cancer

OBJECTIVES

The galactomannan (GM) test is a useful method for early diagnosis of invasive aspergillosis. Recently, multiple myeloma has newly been suggested to be related to false-positive results of GM. We performed a case-control study to validate this finding.

METHODS

Electronic medical records were reviewed for patients admitted March through June 2014. Patients with false-positive GM results were selected as cases and those with negatives as controls. To verify the results of the four-month analysis, additional analysis was performed in multiple myeloma patients over a three-year period.

RESULTS

There were 30 false-positive and 316 negative cases during the four-month period. Among the factors evaluated, multiple myeloma was the only significant factor in the adjusted analysis (OR = 3.59, CI 1.28-10.04). In the three-year analysis of 145 multiple myeloma patients, 25.5% showed false-positive results, which was 3 times higher than overall. GM false-positivity was not related to serum monoclonal protein level or type of immunoglobulin. GM optical density indexes (ODIs) in all false positives were lower than 3.0.

CONCLUSIONS

Multiple myeloma was a major cause of GM false-positivity in adult cancer patients. GM was false-positive in 25.5% of multiple myeloma patients with GM ODIs lower than 3.0.

Nonspecific elevation of serum Aspergillus galactomannan antigen levels in patients with rheumatoid arthritis

BACKGROUND

Infections are an important cause of morbidity and mortality in patients with rheumatoid arthritis. Patients receiving immunosuppressive or anti-tumor necrosis factor (TNF) agents are vulnerable to fungal infections, including those derived from Aspergillus species. Detection of the Aspergillus galactomannan antigen in serum is useful for the early diagnosis of invasive aspergillosis in patients with hematological malignancies. However, its usefulness for detecting early invasive aspergillosis in rheumatoid arthritis patients remains unestablished.

METHODS

Galactomannan antigen levels were measured in 340 patients (311 female patients). For patients who exhibited galactomannan antigen levels ≥0.5 during the initial examination, a second examination was performed 3-6 months later. Conventional blood tests and chest radiography were also performed.

RESULTS

Elevated galactomannan antigen levels (≥0.5) were observed in 62 (18.2%) of 340 patients during the initial examination. A second examination was performed in 56 of 62 patients, 50 of whom exhibited elevated antigen levels. Elevated antigen levels were not associated with the use of any drug including anti-TNF agents. Serum galactomannan antigen levels were correlated with the albumin/globulin ratio (r=-0.19, p<0.001), γ-globulin (%; r=0.17, p=0.001), and hemoglobin concentration (r=-0.15, p=0.005). No patient was clinically diagnosed with invasive aspergillosis during the study period.

CONCLUSIONS

Serum galactomannan antigen levels are frequently elevated in a nonspecific manner in patients with rheumatoid arthritis.

Generic piperacillin/tazobactam is not associated with galactomannan false-positivity in adult patients with cancer: a case-control study

Recent products of piperacillin/tazobactam (PTZ) from the original manufacturer, previously considered a major cause of galactomannan (GM) false-positivity, are reported not to be related to it. However, data regarding generic PTZ are limited and controversial. To evaluate the effect of generic PTZ on GM false-positivity in Korea, we performed a case-control study in adult patients with cancer. A case-control study was designed. Electronic medical records of cancer patients who were admitted and tested for serum GM between March and June 2014 at a tertiary care university hospital were reviewed. During the study period, a single generic PTZ (C manufacturer, Korea) was used. Patients who received PTZ within 24 h prior to serum GM testing were enrolled. Age- and GM test date-matched non-PTZ patients were selected as controls. A total of 110 patients received PTZ within 24 h prior to serum GM testing during the study period. The GM optical density index (ODI) of the PTZ group did not vary significantly from that of the control group (p = 0.251). The percentage of false-positive patients in the PTZ group was also similar to that of the control group (p = 0.538). There was no statistical relationship between GM ODI titer and time interval from PTZ administration (p = 0.095) or cumulative PTZ dose (p = 0.416). In a case-control study that evaluated 220 patients, a generic PTZ in Korea was not related to GM false-positivity.

Multicenter evaluation of a lateral-flow device test for diagnosing invasive pulmonary aspergillosis in ICU patients

Introduction

The incidence of invasive pulmonary aspergillosis (IPA) in intensive care unit (ICU) patients is increasing, and early diagnosis of the disease and treatment with antifungal drugs is critical for patient survival. Serum biomarker tests for IPA typically give false-negative results in non-neutropenic patients, and galactomannan (GM) detection, the preferred diagnostic test for IPA using bronchoalveolar lavage (BAL), is often not readily available. Novel approaches to IPA detection in ICU patients are needed. In this multicenter study, we evaluated the performance of an Aspergillus lateral-flow device (LFD) test for BAL IPA detection in critically ill patients.

Methods

A total of 149 BAL samples from 133 ICU patients were included in this semiprospective study. Participating centers were the medical university hospitals of Graz, Vienna and Innsbruck in Austria and the University Hospital of Mannheim, Germany. Fungal infections were classified according to modified European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria.

Results

Two patients (four BALs) had proven IPA, fourteen patients (sixteen BALs) had probable IPA, twenty patients (twenty-one BALs) had possible IPA and ninety-seven patients (one hundred eight BALs) did not fulfill IPA criteria. Sensitivity, specificity, negative predictive value, positive predictive value and diagnostic odds ratios for diagnosing proven and probable IPA using LFD tests of BAL were 80%, 81%, 96%, 44% and 17.6, respectively. Fungal BAL culture exhibited a sensitivity of 50% and a specificity of 85%.

Conclusion

LFD tests of BAL showed promising results for IPA diagnosis in ICU patients. Furthermore, the LFD test can be performed easily and provides rapid results. Therefore, it may be a reliable alternative for IPA diagnosis in ICU patients if GM results are not rapidly available.

Trial registration

ClinicalTrials.gov NCT02058316. Registered 20 January 2014.

Diagnosis and antimicrobial therapy of lung infiltrates in febrile neutropenic patients (allogeneic SCT excluded): updated guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Up to 25% of patients with profound neutropenia lasting for >10 days develop lung infiltrates, which frequently do not respond to broad-spectrum antibacterial therapy. While a causative pathogen remains undetected in the majority of cases, Aspergillus spp., Pneumocystis jirovecii, multi-resistant Gram-negative pathogens, mycobacteria or respiratory viruses may be involved. In at-risk patients who have received trimethoprim-sulfamethoxazole (TMP/SMX) prophylaxis, filamentous fungal pathogens appear to be predominant, yet commonly not proven at the time of treatment initiation. Pathogens isolated from blood cultures, bronchoalveolar lavage (BAL) or respiratory secretions are not always relevant for the etiology of pulmonary infiltrates and should therefore be interpreted critically. Laboratory tests for detecting Aspergillus galactomannan, β-D-glucan or DNA from blood, BAL or tissue samples may facilitate the diagnosis; however, most polymerase chain reaction assays are not yet standardized and validated. Apart from infectious agents, pulmonary side-effects from cytotoxic drugs, radiotherapy or pulmonary involvement by the underlying malignancy should be included into differential diagnosis and eventually be clarified by invasive diagnostic procedures. Pre-emptive treatment with mold-active systemic antifungal agents improves clinical outcome, while other microorganisms are preferably treated only when microbiologically documented. High-dose TMP/SMX is first choice for treatment of Pneumocystis pneumonia, while cytomegalovirus pneumonia is treated primarily with ganciclovir or foscarnet in most patients. In a considerable number of patients, clinical outcome may be favorable despite respiratory failure, so that intensive care should be unrestrictedly provided in patients whose prognosis is not desperate due to other reasons.

Pulmonary toxocariasis mimicking invasive aspergillosis in a patient with ulcerative colitis

A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia.

Drug–laboratory interaction between beta-lactam antibiotics and the galactomannan antigen test used to detect mould infections

Several studies have demonstrated that piperacillin/tazobactam produces a false-positive result for the galactomannan antigen test. However, the most recent literature has demonstrated that this interaction is no longer a concern. There is little information regarding the drug–laboratory interaction with the generics of piperacillin/tazobactam or other broad-spectrum beta-lactams, such as ceftaroline, doripenem, imipenem/cilastatin, and meropenem. The purpose of this study was to determine if a drug–laboratory interaction exists with these antibiotics. Tests showed that one lot of imipenem/cilastatin by Hospira Healthcare India Private Limited produced a false-positive result for the galactomannan antigen test. All other medications tested, including piperacillin/tazobactam from seven manufacturers and imipenem/cilastatin by Hospira Inc., did not produce positive results. Since the reason for this drug–laboratory interaction with imipenem/cilastatin is unknown, more studies are needed to further investigate this interaction. Providers also should be educated of these findings: no drug–laboratory interaction with piperacillin/tazobactam and a possible drug–laboratory interaction with imipenem/cilastatin (Hospira Healthcare India Private Limited).

Use and limits of (1-3)-β-d-glucan assay (Fungitell), compared to galactomannan determination (Platelia Aspergillus), for diagnosis of invasive aspergillosis

This study was undertaken to examine the performance of the Fungitell β-glucan (BG) assay, to compare it with that of the galactomannan (GM) test for the diagnosis of invasive aspergillosis (IA) in patients with hematological malignancies, and to examine the rates of false-positive BG and GM test results due to β-lactam antibiotics among sera of patients with Gram-positive or Gram-negative bacteremia and selected sera with false-positive results from the GM test. Serum samples from 105 patients with proven (n = 14) or probable (n = 91) IA, 97 hematology patients at risk for invasive fungal infections, 50 healthy blood donors, and 60 patients with bacteremia were used to study the sensitivities and specificities of the assays. The GM test was more specific than the BG assay (97% versus 82%, respectively; P = 0.0001) and the BG assay was more sensitive than the GM test (81% versus 49%, respectively; P < 0.0001) for IA diagnosis. The study of 49 separate batches of β-lactam antibiotics showed high and very similar rates of false-positive results for the GM and BG assays (29 and 33%, respectively; P = 0.82) but with an almost complete lack of concordance between the 2 assays. For patients with bacteremia, the rate of false-positive results was much higher with the BG test than with the GM test (37% versus 2%, respectively; P < 0.0001), with no significant difference between Gram-positive and Gram-negative bacteremia. In conclusion, the BG test may be useful for the diagnosis of IA because of its high sensitivity in comparison with the GM test, but the overall benefit of this assay remains limited because of its inadequate specificity and its cost.

Nonmolecular methods for the diagnosis of respiratory fungal infections

Diagnosis of invasive fungal pneumonias by conventional culture methods is difficult to assess and often delayed. Nonmolecular fungal markers have emerged as an important adjunctive tool to support their diagnosis in combination with other clinical, radiologic, and microbiological criteria of invasive fungal diseases. Concerns about the sensitivity and specificity of some tests in different patient populations should lead to warnings about their widespread use. None can identify the emerging and particularly deadly fungal pathogens responsible for mucormycosis. The role of nonmolecular fungal markers should be better defined in combination with other microbiological and radiologic tools in preemptive antifungal strategies.

Reduction in false-positive Aspergillus serum galactomannan enzyme immunoassay results associated with use of piperacillin-tazobactam in the United States

Piperacillin-tazobactam (PTZ) is known to cause false-positive results in the Platelia Aspergillus enzyme-linked immunoassay (EIA), due to contamination with galactomannan (GM). We tested 32 lots of PTZ and 27 serum specimens from patients receiving PTZ. GM was not detected in the lots of PTZ; one serum specimen (3.7%) was positive. PTZ formulations commonly used in the United States today appear to be a rare cause for false-positive GM results.

Host biomarkers of invasive pulmonary aspergillosis to monitor therapeutic response

Invasive pulmonary aspergillosis (IPA) is a life-threatening disease of immunocompromised patients that requires aggressive therapy. Detection of the disease and monitoring of the therapeutic response during IPA are complex, and current molecular diagnostics are not suitably robust. Here, we explored proteomic profiles of bronchoalveolar lavage fluid (BALF) specimens from a persistently neutropenic rabbit model of IPA. Three experimental arms, uninfected control animals, infected untreated animals, and animals infected and treated with ravuconazole/amphotericin B, were studied. Total proteins were evaluated by two-dimensional (2D) gel electrophoresis, followed by matrix-assisted laser desorption ionization-time of flight/time of flight (MALDI-TOF/TOF) mass spectrometry (MS) and quantified by enzyme-linked immunosorbent assay (ELISA). Host-derived proteins haptoglobin (Hp), C-reactive protein (CRP), and annexin A1 (Anx A1) were prominently found in BALF during the IPA infection and showed significant changes in response to antifungal therapy (P < 0.0001). In serum, differences in Hp (P = 0.0001) between infected and treated rabbits were observed. Preliminary in vitro studies revealed that Aspergillus fumigatus-secreted proteases may contribute to the cleavage of Anx A1 during IPA. In summary, host protein biomarkers Hp, CRP, and Anx A1 may have value in monitoring therapeutic response to antifungal agents in IPA patients with confirmed disease.