Correlation between galactomannan antigen levels in serum and neutrophil counts in haematological patients with invasive aspergillosis

Diagnosing fungal infections in clinical practice: a narrative review

BACKGROUND

Invasive fungal infections (IFI) present a major medical challenge, with an estimated 6.5 million cases annually, resulting in 3.8 million deaths. Pathogens such as Aspergillus spp. Candida spp. Mucorales spp. Cryptococcus spp. and other fungi species contribute to these infections, posing risks to immunocompromised individuals. Early and accurate diagnosis is crucial for effective treatment and better patient outcomes.

AREAS COVERED

This narrative review provides an overview of the current methods and challenges associated with diagnosing fungal diseases, including invasive aspergillosis and invasive candidiasis, as well as rare and endemic fungal infections. Various diagnostic techniques, including microscopy, culture, molecular diagnostics, and serological tests, are reviewed, highlighting their respective advantages and limitations and role in clinical guidelines. To illustrate, the need for improved diagnostic strategies to overcome existing challenges, such as the low sensitivity and specificity of current tests and the time-consuming nature of traditional culture-based methods, is addressed.

EXPERT OPINION

Current advancements in fungal infection diagnostics have significant implications for healthcare outcomes. Improved strategies like molecular testing and antigen detection promise early detection of fungal pathogens, enhancing patient management. Challenges include global access to advanced technologies and the need for standardized, user-friendly point-of-care diagnostics to improve diagnosis of fungal infections globally.

Performance of the IMMY® sona Aspergillus lateral flow assay for the detection of galactomannan in tracheal aspirate samples from Brazilian patients with COVID-19-associated pulmonary aspergillosis: Cross-sectional and systematic review of literature

During the COVID-19 pandemic, many patients in intensive care units (ICUs) were affected by invasive fungal infections, including aspergillosis, contributing to a high mortality rate. Diagnosing proven COVID-19-associated pulmonary aspergillosis (CAPA) requires clinical and radiological evaluations, along with laboratory testing of bronchoalveolar lavage samples or lung biopsies. However, these procedures and equipment are often inaccessible in developing countries or regions with limited resources, including Brazil. Consequently, alternative diagnostic methods, such as measuring Aspergillus galactomannan (GM) in tracheal aspirate (TA), have been explored for CAPA diagnosis. Nonetheless, research on the efficacy of TA-based diagnostic tests is limited. This study aimed to assess the performance of the IMMY® Sona Aspergillus lateral flow assay (LFA) for GM detection in TA samples from 60 ICU patients with suspected CAPA at two tertiary hospitals in Campo Grande, Brazil. The ELISA method (Platelia Aspergillus AG, Bio-Rad®) was used to detect Aspergillus GM in TA samples, serving as the microbiological criterion and reference test. Fifteen patients (12.4%) were identified as having possible CAPA. The overall accuracy of LFA was 94%, and the tests demonstrated an agreement of 93.1% (Cohen's kappa of 0.83). Based on our findings, the LFA for Aspergillus GM detection in TA samples exhibited excellent performance, proving to be a valuable diagnostic tool for potential CAPA. In a systematic review, two studies were included, and the meta-analysis revealed pooled estimates provided a sensitivity of 86% (95% CI, 80%-91%) and specificity of 93% (95% CI, 86%-97%). The diagnostic odds ratio (DOR) for identification of Aspergillus using LFA was 103.38 (95% CI, 38.03-281.03). Despite its lower sensitivity compared to our study, the LFA appears to be a promising diagnostic option for CAPA, particularly in suspected cases that have not received antifungal therapy. This enables timely antifungal treatment and could reduce mortality rates in regions where bronchoscopy is unavailable or limited.

Improved diagnostic markers for invasive pulmonary aspergillosis in COPD patients

Background

The prevalence of invasive pulmonary aspergillosis (IPA) among patients with chronic obstructive pulmonary disease (COPD) is steadily increasing, leading to high mortality. Although early diagnosis can significantly reduce mortality, the efficacy of current diagnostic methods is limited. Consequently, there is a need for novel approaches for early IPA detection.

Methods

This retrospective study involved 383 hospitalized COPD patients with GOLD stages III and IV. The IPA group (67 patients) and non-IPA group (316 patients) were identified at the First Affiliated Hospital of Guangzhou Medical University between January 2016 and February 2022. We analyzed common serological indicators in our hospital to identify predictive indicators for the early diagnosis of IPA in COPD patients.

Results

The sensitivity and specificity of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), lactate dehydrogenase (LDH), and ceruloplasmin (CER) for diagnosing IPA in COPD patients were as follows: CRP (91.2%, 57.7%), ESR (77.5%, 73.0%), PCT (60.5%, 71.4%), LDH (50.0%, 88.8%), and CER (60.7%, 74.3%). Combinations of biomarkers, such as CRP-ESR, CRP-LDH, ESR-LDH, ESR-CER, and LDH-CER, showed promising diagnostic potential, with larger area under the curve (AUC) values for IPA diagnosis in COPD patients. However, no statistically significant difference was observed between the diagnostic efficacy of single biomarkers and combined biomarkers. Notably, compared to those in the unassisted ventilation group, the patients in the assisted ventilation group (including noninvasive ventilation and tracheal intubation/incision-assisted ventilation group) exhibited significantly greater PCT and LDH levels, while the CER significantly decreased (p=0.021). There were no significant differences in biomarker levels between the ICU group and the non-ICU group. CRP (p<0.01), ESR (p=0.028), PCT (p<0.01), and CER (p<0.01) were positively correlated with hospitalization duration, whereas LDH was not correlated with hospitalization duration.

Conclusion

Our study highlights the diagnostic potential of CRP, ESR, PCT, LDH, and CER for IPA in COPD patients. CRP and LDH can also initially predict the need for assisted ventilation, while CRP can initially estimate the length of hospitalization. This study represents the first report of the potential of CER for diagnosing IPA, suggesting its significance for further research.

Point-of-care testing for viral-associated pulmonary aspergillosis

INTRODUCTION

Over the last years, severe respiratory viral infections, particularly those caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the influenza virus, have emerged as risk factor for viral-associated pulmonary aspergillosis (VAPA) among critically ill patients. Delays in diagnosis of VAPA are associated with increased mortality. Point-of-care-tests may play an important role in earlier diagnosis of VAPA and thus improve patient outcomes.

AREAS COVERED

The following review will give an update on point-of-care tests for VAPA, analyzing performances in respiratory and blood specimens.

EXPERT OPINION

Point-of-care tests have emerged, and particularly the IMMY Aspergillus galactomannan lateral flow assay (LFA) shows performances comparable to the galactomannan ELISA for diagnosis of VAPA. Notably, nearly all evaluations of POC tests for VAPA have been performed in COVID-19 patients, with very limited data in influenza patients. For early diagnosis of COVID associated pulmonary aspergillosis (CAPA), the LFA has shown promising performances in respiratory samples, particularly in bronchoalveolar lavage fluid, and may thereby help in improving patient outcomes. In contrast, serum LFA testing may not be useful for early diagnosis of disease, except in cases with invasive tracheobronchial aspergillosis.

Acute Invasive Pulmonary Aspergillosis: Clinical Presentation and Treatment

Among all clinical manifestations of pulmonary aspergillosis, invasive pulmonary aspergillosis (IPA) is the most acute presentation. IPA is caused by Aspergillus hyphae invading the pulmonary tissue, causing either tracheobronchitis and/or bronchopneumonia. The degree of fungal invasion into the respiratory tissue can be seen as a spectrum, going from colonization to deep tissue penetration with angio-invasion, and largely depends on the host's immune status. Patients with prolonged, severe neutropenia and patients with graft-versus-host disease are at particularly high risk. However, IPA also occurs in other groups of immunocompromised and nonimmunocompromised patients, like solid organ transplant recipients or critically ill patients with severe viral disease. While a diagnosis of proven IPA is challenging and often warranted by safety and feasibility, physicians must rely on a combination of clinical, radiological, and mycological features to assess the likelihood for the presence of IPA. Triazoles are the first-choice regimen, and the choice of the drug should be made on an individual basis. Adjunctive therapy such as immunomodulatory treatment should also be taken into account. Despite an improving and evolving diagnostic and therapeutic armamentarium, the burden and mortality of IPA still remains high. This review aims to give a comprehensive and didactic overview of the current knowledge and best practices regarding the epidemiology, clinical presentation, diagnosis, and treatment of acute IPA.

Performance of the Aspergillus galactomannan lateral flow assay with a digital reader for the diagnosis of invasive aspergillosis: a multicenter study

PURPOSE

The objective of this multicenter study was to compare the diagnostic performance of lateral flow assay (LFA) and enzyme-linked immunosorbent assay (ELISA) to detect the Dynamiker Aspergillus Galactomannan levels in serum and bronchoalveolar lavage fluid (BALF) samples for I.

METHODS

We registered 310 clinically suspected Aspergillus infection patients from December 2021 to February 2023 and classified them into subgroups as the "IA group" and "non-IA group" based on the latest EORTC/MSG guidelines. The immunoassays were analyzed by LFA and ELISA respectively.

RESULTS

Galactomannan was examined using LFA, and serum and BALF samples demonstrated sensitivities of 82.57% and 89.47%, specificities of 90.76% and 92.00%, PPVs of 89.11% and 96.23%, and NPVs of 85.04% and 79.31%, respectively. Galactomannan was observed using two assays in serum and BALF samples and showed PPAs of 95.11% and 93.33%, NPAs of 89.19% and 96.30%, and TPAs of 92.47% and 94.25%, respectively. The ROC curve demonstrated that LFA had optimum diagnostic value when the index value (I value) = 0.5, the sensitivity was 84.94%, and the specificity was 90.97%.

CONCLUSION

Compared to the ELISA method, the LFA has shown excellent performance for the diagnosis of IA in serum and BALF sample and can be used as an assay for the early diagnosis of patients with IA. The dynamic change in galactomannan levels may be useful for assessing treatment response.

Metagenomic next-generation sequencing for detecting Aspergillosis pneumonia in immunocompromised patients: a retrospective study

Purpose

The identification of Aspergillus by metagenomic next-generation sequencing (mNGS) remains a challenging task due to the difficulty of nucleic acid extraction. The objective of this study was to determine whether mNGS could provide an accurate and efficient method for detecting invasive pulmonary aspergillosis (IPA) in immunocompromised patients (ICP).

Methods

A total of 133 ICP admitted to the ICU between January 2020 and September 2022 were enrolled in the study, of which 46 were diagnosed with IPA and 87 were non-IPA cases. The bronchoalveolar lavage fluid (BALF) was analyzed for the presence of Aspergillosis and other co-pathogens using mNGS, and its diagnostic performance was compared to conventional microbial tests (CMTs) that included smear, cultures, serum and BALF galactomannan (GM) test. Clinical composite diagnosis was used as the reference standard.

Results

mNGS had a sensitivity, specificity, and accuracy of 82.6%, 97.7%, and 92.5%, respectively, in diagnosing IPA. These findings were comparable to those of the combination of multiple CMTs. Interestingly, the sensitivity of mNGS was superior to that of any single CMT method, as demonstrated by comparisons with smears (8.7%, P < 0.001), culture (39.1%, P < 0.001), serum GM (23.9%, P < 0.001) and BALF GM (69.6%, P = 0.031). mNGS was capable of accurately distinguish strains of Aspergillus genus, with a consistency of 77.8% with culture. Furthermore, mNGS also identified A. fumigatus, A. flavus, A. terrestris, A. oryzae and Mucor spp. in culture-negative cases. The sequencing reads of Aspergillus by mNGS exhibited extensive variation, ranging from 11 to1702. A positive correlation was observed between the optical density index of BALF GM and unique reads by mNGS (r = 0.607, P = 0.001) in BALF-GM positive patients. Notably, mNGS was able to diagnose 35 out of 37 cases with mixed infection, with P. jirovecii and cytomegalovirus being the most common co-pathogens.

Conclusions

mNGS presents a feasible and remarkably sensitive approach for detecting Aspergillus in ICP, thereby serving as a valuable adjunctive tool to CMT. Furthermore, mNGS's ability to accurately identify fungal species and co-pathogens can assist in guiding appropriate antimicrobial therapy.

Bronchial aspirate obtained during bronchoscopy yields increased fungal load compared to bronchoalveolar lavage fluid in patients at risk of invasive aspergillosis and Pneumocystis pneumonia

Bronchoalveolar lavage fluid (BALF) is a standard respiratory sample for diagnosing invasive fungal diseases like Pneumocystis pneumonia (PCP) and invasive pulmonary aspergillosis (IPA). However, procedural variations exist across medical centers and wards. This study aimed to compare the diagnostic potential of BALF and bronchial aspirate (BA) obtained during bronchoscopy in 173 patients suspected of fungal infections. A prospective observational study was conducted from April 2020 to November 2021. BALF and BA were collected during bronchoscopy and subjected to direct examination, fungal culture, Aspergillus fumigatus qPCR (AfqPCR), and Pneumocystis jirovecii qPCR (PjqPCR). Galactomannan detection was performed on BALF. Patients were classified based on established European Organization for Research and Treatment of Cancer (EORTC) criteria. Out of 173 patients, 75 tested positive for at least one test in BA or BALF. For Aspergillus, proportion of positive AfqPCR (14.5% vs. 9.2%; P < 0.0001) and fungal loads (Cq of 31.3 vs. 32.8; P = 0.0018) were significantly higher in BA compared to BALF. For Pneumocystis, fungal loads by PjqPCR was also higher in BA compared to BALF (Cq of 34.2 vs. 35.7; P = 0.003). BA only detected A. fumigatus and P. jirovecii in 12 (42.9%) and 8 (19.5%) patients, respectively. BA obtained during a BAL procedure can be a suitable sample type for increased detection of P. jirovecii and A. fumigatus by qPCR. The use of BA in diagnostic algorithms requires further investigation in prospective studies.

Diagnostic Efficacy of Aspergillus Galactomannan Lateral Flow Assay in Patients with Hematological Malignancies: A Prospective Multicenter Study

BACKGROUND

A rapid and reliable diagnostic test is needed to reduce mortality through early diagnosis of invasive aspergillosis (IA) in patients with hematological malignancies.

OBJECTIVE

To evaluate the efficacy of serum and bronchoalveolar lavage (BAL) Aspergillus galactomannan lateral flow assay (GM-LFA) in IA diagnosis and determine the correlation of GM-LFA with GM enzyme immunoassay (GM-EIA) in patients with hematological malignancies.

METHODS

In this prospective multicenter study, we used serum and BAL fluid samples from patients with hematological malignancies and suspected IA and performed GM-LFA and GM-EIA. According to the EORTC/MSGERC criteria, patients were grouped as proven (n = 6), probable (n = 22), possible IA (n = 55), or no IA (n = 88). The performance of serum GM-LFA at 0.5 optical density index (ODI) and area under the curve (AUC) were calculated. Spearman's correlation analysis and kappa statistics were performed to determine the agreement between the tests.

RESULTS

GM-LFA showed an AUC of 0.832 in proven/probable IA (sensitivity [SEN], specificity [SPE], negative predictive value [NPV], and diagnostic accuracy were 75%, 100%, 92.6%, and 93.9%, respectively, at a 0.5 ODI) versus that in no IA. A moderate positive correlation was noted between the GM-LFA and GM-EIA scores (p = 0.01). The observed agreement between the tests at 0.5 ODI was almost perfect (p < 0.001). After excluding patients who received mold-active antifungal prophylaxis or treatment, the SEN, SPE, NPV, and diagnostic accuracy for proven/probable IA were 76.2%, 100%, 93.3%, and 94.5%, respectively.

CONCLUSIONS

Serum GM-LFA demonstrated high discriminatory power and good diagnostic performance for IA in patients with hematological malignancies.

The SSS revolution in fungal diagnostics: speed, simplicity and sensitivity

INTRODUCTION

Fungal disease has historically presented a diagnostic challenge due to its often non-specific clinical presentations, relative infrequency and reliance on insensitive and time-intensive fungal culture.

SOURCES OF DATA

We present the recent developments in fungal diagnostics in the fields of serological and molecular diagnosis for the most clinically relevant pathogens; developments that have the potential to revolutionize fungal diagnosis through improvements in speed, simplicity and sensitivity. We have drawn on a body of evidence including recent studies and reviews demonstrating the effectiveness of antigen and antibody detection and polymerase chain reaction (PCR) in patients with and without concurrent human immunodeficiency virus infection.

AREAS OF AGREEMENT

This includes recently developed fungal lateral flow assays, which have a low cost and operator skill requirement that give them great applicability to low-resource settings. Antigen detection for Cryptococcus, Histoplasma and Aspergillus spp. are much more sensitive than culture. PCR for Candida spp., Aspergillus spp., Mucorales and Pneumocystis jirovecii is more sensitive than culture and usually faster.

AREAS OF CONTROVERSY

Effort must be made to utilize recent developments in fungal diagnostics in clinical settings outside of specialist centres and integrate their use into standard medical practice. Given the clinical similarities of the conditions and frequent co-infection, further study is required into the use of serological and molecular fungal tests, particularly in patients being treated for tuberculosis.

GROWING POINTS

Further study is needed to clarify the utility of these tests in low-resource settings confounded by a high prevalence of tuberculosis.

AREAS TIMELY FOR DEVELOPING RESEARCH

The diagnostic utility of these tests may require revision of laboratory work flows, care pathways and clinical and lab coordination, especially for any facility caring for the immunosuppressed, critically ill or those with chronic chest conditions, in whom fungal disease is common and underappreciated.

The clinical spectrum of aspergillosis in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. In this review, we present the clinical spectrum and pathogenesis of syndromes caused by Aspergillus in COPD namely invasive aspergillosis (IA), community-acquired Aspergillus pneumonia, chronic pulmonary Aspergillosis and Aspergillus sensitisation. Some of these entities are clearly linked to COPD, while others may coexist, but are less clearly liked directly to COPD. We discuss current uncertainties as these pertain to IA in COPD cohorts and explore areas for future research in this field.

Role of (1-3)-Β-D-Glucan Test in the Diagnosis of Invasive Fungal Infections among High-Risk Patients in a Tertiary Care Hospital

Background  Invasive fungal infections (IFI) are associated with high mortality. Serum fungal biomarkers offer an advantage over the traditional methods in early diagnosis and better clinical outcomes. The aim of the study was to evaluate the role of (1–3)-β-D-glucan (BDG) assay in the patients suspected of IFI.

Materials and Methods  This prospective study was conducted in the Department of Microbiology, Dayanand Medical College and Hospital, Ludhiana, over a period of 1 year. A total of 862 serum samples were received from patients suspected of IFI, for the BDG test (Fungitell, Associates of Cape Cod Inc., USA). The test was performed as per kit protocol. Appropriate samples were processed for KOH fungal smear and fungal culture. Blood culture was done by Bactec (Biomerieux).

Statistical Analysis  Results were analyzed using descriptive statistical methods. Sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated at different cutoffs. In addition, the receiver operating characteristic (ROC) curve using SPSS 21.00 software was calculated and the diagnostic accuracy was shown by the area under the ROC curve (AUC).

Results  Among 862 patients, 546 (63.3%) were males. The predominant age group (25.6%) was between 61 and 70 years. The most common risk factor (54.8%) was prolonged intensive care unit stay. Out of the total samples, 455 (52.8%) samples were found positive for BDG. Fungal elements were seen in 48 (10.5%) KOH smears and fungal growth was obtained in 81 (17.8%) cultures. Comparison of BDG assay and culture at different cutoffs yielded AUC—0.823. Sensitivity (100%), specificity (51.3%), accuracy (55.6%), PPV (15.8%), and NPV (100%) were observed at the kit cutoff of 80 pg/mL. Optimum sensitivity and specificity of 79.2% and 70.3%, respectively, were observed at a cutoff of 142.4pg/mL. A significant correlation was observed between BDG positivity and piperacillin–tazobactam use and dialysis. Among BDG positive patients, 38(8.4%) succumbed to death.

Conclusion  Detection of BDG helps in the early diagnosis of IFI in critically ill patients. As the assay has a high NPV, a negative test can be used to stop the empirical antifungal drugs. The use of a higher cutoff can be useful to avoid false-positive results.

COVID-19-Associated Pulmonary Aspergillosis, Fungemia, and Pneumocystosis in the Intensive Care Unit: a Retrospective Multicenter Observational Cohort during the First French Pandemic Wave

The aim of this study was to evaluate diagnostic means, host factors, delay of occurrence, and outcome of patients with COVID-19 pneumonia and fungal coinfections in the intensive care unit (ICU). From 1 February to 31 May 2020, we anonymously recorded COVID-19-associated pulmonary aspergillosis (CAPA), fungemia (CA-fungemia), and pneumocystosis (CA-PCP) from 36 centers, including results on fungal biomarkers in respiratory specimens and serum. We collected data from 154 episodes of CAPA, 81 of CA-fungemia, 17 of CA-PCP, and 5 of other mold infections from 244 patients (male/female [M/F] ratio = 3.5; mean age, 64.7 ± 10.8 years). CA-PCP occurred first after ICU admission (median, 1 day; interquartile range [IQR], 0 to 3 days), followed by CAPA (9 days; IQR, 5 to 13 days), and then CA-fungemia (16 days; IQR, 12 to 23 days) (P < 10-4). For CAPA, the presence of several mycological criteria was associated with death (P < 10-4). Serum galactomannan was rarely positive (<20%). The mortality rates were 76.7% (23/30) in patients with host factors for invasive fungal disease, 45.2% (14/31) in those with a preexisting pulmonary condition, and 36.6% (34/93) in the remaining patients (P = 0.001). Antimold treatment did not alter prognosis (P = 0.370). Candida albicans was responsible for 59.3% of CA-fungemias, with a global mortality of 45.7%. For CA-PCP, 58.8% of the episodes occurred in patients with known host factors of PCP, and the mortality rate was 29.5%. CAPA may be in part hospital acquired and could benefit from antifungal prescription at the first positive biomarker result. CA-fungemia appeared linked to ICU stay without COVID-19 specificity, while CA-PCP may not really be a concern in the ICU. Improved diagnostic strategy for fungal markers in ICU patients with COVID-19 should support these hypotheses. IMPORTANCE To diagnose fungal coinfections in patients with COVID-19 in the intensive care unit, it is necessary to implement the correct treatment and to prevent them if possible. For COVID-19-associated pulmonary aspergillosis (CAPA), respiratory specimens remain the best approach since serum biomarkers are rarely positive. Timing of occurrence suggests that CAPA could be hospital acquired. The associated mortality varies from 36.6% to 76.7% when no host factors or host factors of invasive fungal diseases are present, respectively. Fungemias occurred after 2 weeks in ICUs and are associated with a mortality rate of 45.7%. Candida albicans is the first yeast species recovered, with no specificity linked to COVID-19. Pneumocystosis was mainly found in patients with known immunodepression. The diagnosis occurred at the entry in ICUs and not afterwards, suggesting that if Pneumocystis jirovecii plays a role, it is upstream of the hospitalization in the ICU.

Invasive aspergillosis in critically ill patients: Review of definitions and diagnostic approaches

Invasive aspergillosis (IA) is an increasingly recognised phenomenon in critically ill patients in the intensive care unit, including in patients with severe influenza and severe coronavirus disease 2019 (COVID-19) infection. To date, there are no consensus criteria on how to define IA in the ICU population, although several criteria are used, including the AspICU criteria and new consensus criteria to categorise COVID-19-associated pulmonary aspergillosis (CAPA). In this review, we describe the epidemiology of IA in critically ill patients, most common definitions used to define IA in this population, and most common clinical specimens obtained for establishing a mycological diagnosis of IA in the critically ill. We also review the most common diagnostic tests used to diagnose IA in this population, and lastly discuss the most common clinical presentation and imaging findings of IA in the critically ill and discuss areas of further needed investigation.

Diagnostic value of serum human Galactomannan aspergillus antigen and 1,3-beta-D-glucan in immunocompromised patient suspected fungal infection

BACKGROUND

The prevalence of fungal infection (FI) in developing countries is high, but the diagnosis of FI is still challenging to determine, so it is needed evaluation of biomarkers other than microbiological culture, because the culture has low sensitivity, high cost, not available in every laboratory and needs a long time. The detection of human galactomannan Aspergillus antigen (GAL) and 1,3-beta-D-glucan (BDG) on the fungal cell wall could be the promising biomarkers for fungal infection. Neutropenia, lymphopenia and CD4T cells in the immunocompromised patients are essential factors, but these cell associations with BDG and GAL levels have not been evaluated yet. The study aimed to evaluate GAL and BDG for detecting fungal infection and their association with total leucocyte count, neutrophil, monocyte, lymphocyte and CD4T cells.

METHOD

A cross-sectional study was conducted among 86 patient with suspected FI. Fungal infection established using EORTC/MSG criteria. Serology test performed using ELISA. Leucocyte cells were measured using a haematology autoanalyser, and CD4T cells were analysed using BD FACSPresto. Statistical analysis obtained using Spearman's correlation coefficient, ROC curve analysis and 2 × 2 contingency table.

RESULTS

Serum Galactomannan and BDG had a significant correlation with CD4T cells and total lymphocyte count (p < 0.05). The cut-off OD GAL >0.3 had sensitivity 54.6%, specificity 87.5% and AUC 0.71; meanwhile, the BDG cut-off >115.78 pg/ mL had sensitivity 71.2%, specificity 52.4% and AUC 0.63 for detecting fungal infection.

CONCLUSIONS

The immunocompromised patients can undergo GAL for determining the diagnose of FI. The lower the CD4T cells and total lymphocyte count, the higher the GAL and BDG serum levels.

Role of Voriconazole in the Management of Invasive Central Nervous System Aspergillosis: A Case Series from a Tertiary Care Centre in India

Invasive central nervous system (CNS) aspergillosis is acquired by either hematogenous dissemination or direct spread from a sinus infection. We describe a series of nine patients with CNS aspergillosis from a tertiary care teaching institute in North India who were treated with voriconazole alone or in combination with surgery. All patients who had clinical and radiological features consistent with fungal CNS infection, showed the presence of septate hyphae on histopathology/microscopy and were either culture positive for Aspergillus spp. or had serum galactomannan positivity were diagnosed as CNS aspergillosis. Clinical features, risk factors, diagnostic modalities, treatment details and outcome at last follow-up were recorded for all patients diagnosed with CNS aspergillosis. A total of nine patients were diagnosed with CNS aspergillosis. The median duration of presentation at our hospital was six months (IQR-2-9 months). Six patients had concomitant sinus involvement, while two patients had skull-base involvement as well. All patients were treated with voriconazole therapy, and three of these patients underwent surgery. All but one patient survived at the last follow-up (median duration was 14 months (IQR- 8-21.5). Two patients had complete resolution, and voriconazole was stopped at the last follow-up, and the rest of the patients were continued on voriconazole. Of the six patients who were continued on voriconazole, all but one had more than 50% radiological resolution on follow-up imaging. Invasive CNS aspergillosis is an important cause of CNS fungal infection that is often diagnosed late and requires long-term voriconazole-based therapy.

Recovery of a triazole-resistant Aspergillus fumigatus in respiratory specimen of COVID-19 patient in ICU - A case report

Although invasive pulmonary aspergillosis (IPA) is typically described in immunocompromised host, patient with severe influenzae can develop IPA. Similarly, patients with severe COVID-19 complicated with IPA are increasingly reported. Here, we describe a case of invasive aspergillosis with triazole-resistant A. fumigatus (TR34/L98H mutation) in a 56-year-old patient with COVID-19 in intensive care unit. This report highlights the need to define the available tools for diagnosis of invasive aspergillosis in severe COVID-19 patients.

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Association between COVID-19 and invasive aspergillosis.

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Early screening for aspergillosis should be performed in respiratory specimen.

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This case emphasizes the need to screen isolates for pan-azole resistance.

Advances in the diagnosis of fungal pneumonias

INTRODUCTION

Fungal infections are increasingly encountered in clinical practice due to more favorable environmental conditions and increasing prevalence of immunocompromised individuals. The diagnostic approach for many fungal pathogens continues to evolve. Herein, we outline available diagnostic tests for the most common fungal infections with a focus on recent advances and future directions.

AREAS COVERED

We discuss the diagnostic testing methods for angioinvasive molds (Aspergillus spp. and Mucor spp.), invasive yeast (Candida spp. and Cryptococcus ssp.), Pneumocystis, and endemic fungi (Blastomyces sp., Coccidioides ssp., and Histoplasma sp.). The PubMed-NCBI database was searched within the past 5 years to identify the most recent available literature with dates extended in cases where literature was sparse. Diagnostic guidelines were utilized when available with references reviewed.

EXPERT OPINION

Historically, culture and/or direct visualization of fungal organisms were required for diagnosis of infection. Significant limitations included ability to collect specimens and delayed diagnosis associated with waiting for culture results. Antigen and antibody testing have made great strides in allowing quicker diagnosis of fungal infections but can be limited by low sensitivity/specificity, cross-reactivity with other fungi, and test availability. Molecular methods have a rich history in some fungal diseases, while others continue to be developed.

Blood Aspergillus PCR: The Good, the Bad, and the Ugly

Invasive Aspergillosis (IA) is one of the most common invasive fungal diseases and is accompanied by high morbidity and mortality. In order to maximize patient outcomes and survival, early and rapid diagnosis has been shown to be pivotal. Hence, diagnostic tools aiding and improving the diagnostic process are ambitiously searched for. In this context, polymerase chain reaction (PCR) may represent a potential candidate. Its additional value and benefits in diagnosis have been demonstrated and are scientifically established. Nevertheless, standardized and widespread usage is sparse because several factors influence diagnostic quality and need to be considered in order to optimize diagnostic performance and outcome. In the following review, the current role of PCR in the diagnosis of IA is explored, with special focus on the strengths and limitations of PCR in different settings.

Comparison of Clinical Manifestation, Diagnosis, and Outcomes of Invasive Pulmonary Aspergillosis and Pulmonary Mucormycosis

Objects: Invasive pulmonary mold infection usually has devastating outcomes. Timely differentiation between invasive pulmonary aspergillosis (IPA) from pulmonary mucormycosis (PM) is critical for treatment decision-making. However, information on IPA and PM differentiation is limited. Methods: We conducted a retrospective, multicenter, observational study, with proven and probable IPA and PM patients from January 2004 to December 2017. Demographics, clinical manifestations, image reports, histopathological findings, and outcomes were analyzed. Results: A total of 46 IPA (33 proven and 13 probable) and 19 PM (18 proven and one probable) cases were analyzed. The majority of tissues (81% in IPA and 61% in PM) were obtained using bronchoscopy. Prior influenza infection was a predisposing factor for IPA, and abscess formation in CT scan was associated with PM (p = 0.0491, p = 0.0454, respectively). The positive culture rate for PM was lower than that for IPA (37% vs. 67%, p = 0.0294). The galactomannan (GM) level from serum and bronchoalveolar lavage (BAL) fluid was significantly higher in IPA than in PM (3.3 ± 0.5 vs. 0.8 ± 0.6, p = 0.0361; 4.0 ± 0.6 vs. 0.59 ± 0.1, p = 0.0473, respectively). The overall mortality rate was 65%, which was similar among IPA and PM groups. Systemic steroid exposure and high Acute Physiology and Chronic Health Evaluation II (APACHE II) scores on admission were independently correlated to mortality in IPA (p = 0.027, p = 0.026, respectively). However, there was no predictor for mortality found in PM patients. Conclusions: Influenza infection, abscess formation in CT scan, and GM level may help physicians to differentiate IPA and PM. Bronchoscopy-guided biopsy and lavage specimen provide timely and definite diagnosis. The prognosis of IPA is associated with systemic steroid exposure and higher APACHE II scores on admission.

β-d-Glucan and Aspergillus Galactomannan assays in the diagnosis of invasive fungal infections

BACKGROUND

With an increase in the number of patients who are immunosuppressed or immunocompromised there has been an increase in invasive fungal infection (IFI) in the past few decades with its associated high morbidity and mortality, ranging from 60% to 90%. The critical problem is the identification of the causative fungus and initiation of appropriate therapy. Hence, there is a requirement for better diagnostic methods for IFI. Detection of markers for the presence of fungi during early stage of the infection, such as constituents of the cell wall or fungal DNA, is essential for timely diagnosis of IFI. Galactomannan (GM) which is a cell wall surface antigen is the most studied diagnostic marker, followed by 1,3 β-d-Glucan (BG) which is seen in deep layers of cell wall.

METHODS

We have assessed the effectiveness of Galactomannan/β-d-Glucan for the early diagnosis of IFI in immunosuppressed patients in our tertiary care setting.

RESULTS

The sensitivity, specificity, positive predictive value and negative predictive value of GM assay were 45%, 93%, 86% and 63% respectively, while the BG assay showed a sensitivity of 78%, specificity of 85%, Positive predictive value (PPV) 84% and Negative predictive value (NPV) 79%.

CONCLUSION

BG assay is better for detection of IFI in patients with immunosuppression. However, a combination of both BG and GM assays would be the best approach as BG assay is highly sensitive, while the GM assay is highly specific for diagnosing IFI.

Impact of unresolved neutropenia in patients with neutropenia and invasive aspergillosis: a post hoc analysis of the SECURE trial

Background

Historically, baseline neutropenia and lack of neutrophil recovery have been associated with poor outcomes in invasive aspergillosis (IA). It is unclear how treatment with the new Aspergillus-active triazoles isavuconazole and voriconazole affects outcomes in neutropenic patients with IA.

Methods

A post hoc analysis of the Phase 3 SECURE trial assessed patients with neutropenia (neutrophil count <0.5 × 109/L for >10 days at baseline) with IA (proven/probable) who had received either isavuconazole or voriconazole. The primary endpoint was all-cause mortality (ACM) through day 42. ACM in patients with resolved versus unresolved neutropenia at day 7 and overall success at end of treatment (EOT) were also assessed.

Results

One hundred and forty-two patients with neutropenia and IA were included (isavuconazole n = 78, voriconazole n = 64). ACM through day 42 (primary endpoint), day 7 and EOT were higher for patients with unresolved versus resolved neutropenia at each timepoint (day 42, unresolved: 45.0% isavuconazole, 45.2% voriconazole; resolved: 5.0% isavuconazole, 5.9% voriconazole; day 7, unresolved: 31.0% isavuconazole, 29.8% voriconazole; resolved: 5.0% isavuconazole, 5.9% voriconazole; EOT, unresolved: 48.6% isavuconazole, 36.4% voriconazole; resolved: 5.0% isavuconazole, 14.3% voriconazole). ACM was significantly higher for isavuconazole-treated patients with unresolved versus resolved neutropenia (day 7, P = 0.031; day 42, P < 0.001; EOT, P < 0.001). In voriconazole-treated patients, ACM was significantly higher among patients with unresolved versus resolved neutropenia at day 42 (P = 0.002) and numerically higher at day 7 and EOT (P > 0.05 for both).

Conclusions

Isavuconazole had comparable efficacy and safety to voriconazole in neutropenic patients with IA. Resolution of neutropenia was associated with improved outcomes.

Triacetylfusarinine C: A urine biomarker for diagnosis of invasive aspergillosis

OBJECTIVES

Early diagnosis of invasive aspergillosis (IA) remains challenging, with available diagnostics being limited by inadequate sensitivities and specificities. Triacetylfusarinine C, a fungal siderophore that has been shown to accumulate in urine in animal models, is a potential new biomarker for diagnosis of IA.

METHODS

We developed a method allowing absolute and matrix-independent mass spectrometric quantification of TAFC. Urine TAFC, normalized to creatinine, was determined in 44 samples from 24 patients with underlying hematologic malignancies and probable, possible or no IA according to current EORTC/MSG criteria and compared to other established biomarkers measured in urine and same-day blood samples.

RESULTS

TAFC/creatinine sensitivity, specificity, positive and negative likelihood ratio for probable versus no IA (cut-off ≥ 3) were 0.86, 0.88, 6.86, 0.16 per patient.

CONCLUSION

For the first time, we provide proof for the occurrence of TAFC in human urine. TAFC/creatinine index determination in urine showed promising results for diagnosis of IA offering the advantages of non-invasive sampling. Sensitivity and specificity were similar as reported for GM determination in serum and bronchoalveolar lavage, the gold standard mycological criterion for IA diagnosis.

A novel diagnosis scoring model to predict invasive pulmonary aspergillosis in the intensive care unit

OBJECTIVES

To improve the quality of invasive pulmonary aspergillosis (IPA) management for intensive care unit (ICU) patients using a practical diagnostic scoring model.

METHODS

This nested case-control study aimed to determine the incidence of IPA in 405 ICU patients, between July 2012 and June 2014, at 6 hospitals in Jakarta, Indonesia. Phenotypic identifications and galactomannan (GM) tests of sera and lung excreta were performed in mycology laboratory, Parasitology Department, Faculty of Medicine, Universitas Indonesia in Jakarta, Indonesia.

RESULTS

The incidence of IPA in the ICUs was 7.7% (31 of 405 patients). A scoring model used for IPA diagnosis showed 4 variables as the most potential risk factors: lung excreta GM index (score 2), solid organ malignancy (score 2), pulmonary tuberculosis (score 2), and systemic corticosteroids (score 1). Patients were included in a high-risk group if their score was greater than 2, and in a low-risk group if their score was less than 2.

CONCLUSION

This study provides a novel diagnosis scoring model to predict IPA in ICU patients. Using this model, a more rapid diagnosis and treatment of IPA may be possible. The application of the diagnosis scoring should be preceded by specified pre-requisites.

Point-of-care diagnosis of invasive aspergillosis in non-neutropenic patients: Aspergillus Galactomannan Lateral Flow Assay versus Aspergillus-specific Lateral Flow Device test in bronchoalveolar lavage

BACKGROUND

We compared new Aspergillus Galactomannan Lateral Flow Assay with the newly formatted Aspergillus-specific Lateral Flow device tests for the diagnosis of invasive pulmonary aspergillosis (IPA) in non-neutropenic patients.

METHODS

We performed both tests in 82 bronchoalveolar lavage fluid samples from 82 patients at risk for IPA but without underlying haematologic malignancy. Samples were collected between September 2016 and September 2018 at the University of California San Diego, United States. IPA was classified following two published consensus criteria.

RESULTS

Classification of cases varied widely between the two consensus criteria. When using criteria established for the intensive care unit, 26/82 patients (32%) met criteria for proven or putative IPA. Both point-of-care assays showed sensitivities ranging between 58% and 69%, with specificities between 68% and 75%. Sensitivity increased up to 81% when both tests were combined.

CONCLUSION

The study outlines the need for updated, unified and more broadly applicable consensus definitions for classifying IPA in non-neutropenic patients, a work that is currently in progress. Both point-of-care tests showed comparable performance, with sensitivities and specificities in the 60%-70% range when used alone and increasing to 80% when used in combination. The new point-of-care tests may serve a role at the bedside in those with clinical suspicion of IPA.

A case of invasive pulmonary aspergillosis during treatment for acute exacerbation of interstitial lung disease

Prolonged immunosuppressive therapy is a risk factor for invasive pulmonary aspergillosis. We report a case of a 79-yearold man who underwent immunosuppressive therapy with methylprednisolone and cyclosporine for an acute exacerbation of interstitial lung disease. Ten days after initiation of immunosuppressive therapy, the patient reported night sweats and purulent sputum, and chest computed tomography scan revealed consolidation. He was diagnosed with invasive pulmonary aspergillosis, and required vasopressor support with oxygen therapy. After the administration of voriconazole and the modulation of immunosuppressive therapy, his condition improved. Short-term immunosuppressive therapy can also induce invasive pulmonary aspergillosis.

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.

Pulmonary Infections in Immunocompromised Hosts: Clinical

Pulmonary infections in immunocompromised patients remain a significant contributor to mortality, morbidity, and health care-associated costs in such a vulnerable patient population. Their epidemiology is changing, set forth by new trends in immunosuppressive regimens and also prophylaxis. The host characteristics, presenting clinical symptomatology, along with radiographic patterns, have also evolved. The microbiology diagnostics are now enriched with nonculture methods for better identification of the causative pathogens. Chest imaging remains the cornerstone of the initial workup. Our article will examine the new trends in epidemiology, clinical findings, and diagnostics for immunocompromised patients with pulmonary infections (transplant recipients, neutropenic hosts, HIV-infected patients, and patients with autoimmune conditions). We will also review the differential diagnosis that most of the times includes malignancies and drug or radiation-related toxicities.

Invasive aspergillosis in patients with underlying liver cirrhosis: a prospective cohort study

The aim of this study was to determine the prevalence of invasive aspergillosis (IA) in patients with liver cirrhosis and the performance of serum galactomannan (GM) screening. Patients with decompensated liver cirrhosis and patients with compensated liver cirrhosis presenting with fever and/or respiratory symptoms were prospectively enrolled. All patients were screened by serum GM twice weekly irrespective of clinical signs and symptoms. Positive serum GM triggered work-up consisting of chest computed tomography and in case of pathological findings bronchoscopy. 150 patients were included in the study. Two (1.3%) had probable, one (0.7%) had possible, and 147 (98%) had no evidence of IA. Both patients with probable IA had compensated liver cirrhosis. Sensitivity for serum GM screening for probable versus no IA was 0.5 (95% CI, 0.09-0.91), specificity 0.97 (95% CI: 0.92-0.99), negative predictive value 0.99 (95% CI, 0.96-0.99) and positive predictive value (PPV) 0.17 (95% CI, 0.01-0.64). PPV was 0.5 (95% CI, 0.03-0.98) in patients with clinical suspicion of IA. In conclusion, prevalence of IA in patients with liver cirrhosis seems to be low. Targeted GM testing in case of clinical suspicion of IA may be associated with markedly higher PPVs when compared to universal GM screening in patients with liver cirrhosis.

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

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

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.

Clinical characteristics, radiologic findings, risk factors and outcomes of serum galactomannan-negative invasive pulmonary aspergillosis

BACKGROUND

The sensitivity of galactomannan (GM) assay is suboptimal for detecting invasive pulmonary aspergillosis (IPA) in serum samples. However, the clinical characteristics, radiologic findings, and outcomes in patients with GM-negative IPA have not been fully elucidated.

METHODS

Over a 7-year period, adult patients with proven or probable IPA by the EORTC/MSG definition were retrospectively enrolled. Patients with negative GM results and positive Aspergillus spp. cultures from sputum or bronchoalveolar lavage were classified into GM-negative IPA group. GM-positive and culture-negative IPA cases were selected at a 1:2 ratio.

RESULTS

Thirty-four patients with GM-negative IPA were compared to 68 randomly selected patients from 158 patients with GM-positive and culture-negative IPA. Patients with diabetes mellitus, chronic kidney disease, and steroid use were more common but those with hematologic malignancy, prior receipt of mold-active antifungal drugs, and neutropenia were less common in GM-negative IPA than in GM-positive IPA. Regarding radiologic findings, angioinvasive aspergillosis was less common in GM-negative IPA than in GM-positive IPA. The median number of days from diagnosis to appropriate antifungal therapy was higher in GM-negative IPA than in GM-positive IPA. Multivariate analysis indicated that neutropenia (adjusted odds ratio [aOR], 0.10) and prior receipt of mold-active antifungal drugs (aOR, 0.12) were inversely associated with GM-negative IPA. The 30-day and 90-day mortality were similar between the two groups.

CONCLUSION

Neutropenia and prior receipt of mold-active antifungal drugs before GM assay were independently associated with GM positivity among patients with proven/probable IPA. Angioinvasive aspergillosis was less common in GM-negative IPA than in GM-positive IPA.

A Review of Diagnostic Methods for Invasive Fungal Diseases: Challenges and Perspectives

Invasive fungal diseases are associated with a high morbidity and mortality, particularly in the context of immunosuppression. Diagnosis of invasive fungal diseases is usually complicated by factors such as poor clinical suspicion and unspecific clinical findings. Access to modern diagnostic tools is frequently limited in developing countries. Here, we describe five real-life clinical cases from a Brazilian tertiary hospital, in order to illustrate how to best select diagnostic tests in patients with different fungal infections.

Challenges in microbiological diagnosis of invasive Aspergillus infections

Invasive aspergillosis (IA) has been increasingly reported in populations other than the historical hematology patients and there are new questions about the performance of microbiological tools. Microscopy and culture have been completed by biomarkers, either antigens or DNA, and in blood or respiratory specimens or both. First studied in hematology, the antigen galactomannan performance in serum is low in other patient populations where the pathophysiology of the infection can be different and the prevalence of IA is much lower. DNA detection with polymerase chain reaction (PCR) in blood or serum (or both) has reached a certain level of acceptance thanks to consensus methods based on real-time quantitative PCR (qPCR). When used on respiratory specimens, galactomannan and qPCR depend on standardization of the sampling and the diverse mycological procedures. Thus, culture remains the main diagnostic criterion in critically ill patients. The current trend toward more effective anti-mold prophylaxis in hematology hampers the yield of a screening strategy, as is usually performed in hematology. Therefore, circulating biomarkers as confirmatory tests should be considered and their performance should be reappraised in each new setting. The use of azole prophylaxis also raises the issue of selecting azole-resistance Aspergillus fumigatus isolates. Ideally, the biomarkers will be more efficient when individual genetic risks of IA are defined. Culture, though not standardized, remains a key element for the diagnosis of IA and has the advantage to easily detect molds other than A. fumigatus. It is still unclear whether next-generation sequencing will replace culture in the future.

Serological Approaches

The diagnosis of invasive fungal diseases (IFD) based on clinical, radiological, and conventional microbiological findings is not reliable and is often delayed. Non-culture-based methods with higher sensitivity and specificity may reduce diagnostic time and result in decreased IFD morbidity and mortality. These methods are now increasingly used to manage patients at risk of IFD. Among available biomarkers, fungal antigens have been investigated as an aid to early diagnosis and are predominantly used as screening tests to prompt antifungal treatment mainly in patients with hematological malignancies. The revised version of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) consensus definitions includes some of these biological markers (galactomannan, 1,3-beta-D-glucan, cryptococcus antigen).

Practice Guidelines for the Diagnosis and Management of Aspergillosis: 2016 Update by the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

Diagnostics and susceptibility testing in Aspergillus

Invasive aspergillosis is a major cause of morbidity and mortality in immunosuppressed patients. Early diagnosis and correct antifungal treatment have a direct impact on patient survival. A number of newer diagnostic procedures have been developed as alternatives to conventional microbiological methods. The detection of fungal components, largely antigens and DNA, are used in clinical laboratories to diagnose invasive aspergillosis. Other rapid diagnostic tests have been recently developed with promising results. However, antifungal resistance is becoming an emerging problem. The detection of this resistance is important to administer the proper antifungal agent. This text reviews the novelties on new diagnostics Aspergillus spp.

PROCEDURES

Intrinsic antifungal resistance and mechanisms of secondary resistance to triazoles in A. fumigatus are also reviewed.

Pneumonia After Hematopoietic Stem Cell Transplantation

Pneumonia is the main cause of morbidity and mortality after hematopoietic stem cell transplantation. Two thirds of pneumonias observed after both autologous and allogeneic stem cell transplantations are of infectious origin, and coinfections are frequent. One third is due to noninfectious process, such as alveolar hemorrhage, alveolar proteinosis, or alloimmune pulmonary complications such as bronchiolitis obliterans or idiopathic interstitial pneumonitis. Most of these noninfectious complications may require treatment with corticosteroids which may be deleterious in infection. On the other hand, these complications either mimic or may be complicated with infections. Therefore, a precise diagnosis of pneumonia is of crucial importance to decide of the optimal treatment. CT scan is the best procedure for imaging of the lung. Although several indirect biomarkers, such as serum or plasma galactomannan or (1-3) β(beta)-G-glucan, can help in the etiological diagnosis, only direct invasive investigations provide the best chance to identify the cause(s) of pneumonia. Bronchoalveolar lavage (BAL) under fiberoptic bronchoscopy is the procedure of choice to identify the cause of pulmonary infection. It is safe and reproducible, and its diagnostic yield is around 50 % if the BAL fluid is processed at the laboratory according to a prespecified protocol established between the transplanter, the infectious diseases’ specialist, the pneumologist, and the laboratory, allowing the identification of the most likely hypotheses. Transbronchial biopsy does not provide significant additional information to BAL in most cases and more often complicates with bleeding and pneumothorax. In case of a noncontributory BAL, the decision to proceed to a second BAL, a transthoracic biopsy, or a surgical biopsy should be cautiously weighted in a multidisciplinary approach in regard to the benefits and risks of invasive procedures versus empirical treatment.

The effect of clinical characteristics on the performance of galactomannan and PCR for the diagnosis of invasive aspergillosis in febrile neutropenic patients

Rapid diagnosis and early treatment of invasive aspergillosis is crucial for the management of the patients with haematological malignancy. We evaluated 358 sera from 78 febrile neutropenic episodes in patient with invasive aspergillosis (IA) (one proven, 17 probable, and 60 possible) and 83 episodes in patients with no IA according to the EORTC/MSG criteria. Patient's specimens were tested by Mycassay Aspergillus PCR (first commercial real-time PCR test) and in house real-time PCR to investigate the presence of Aspergillus DNA, and by ELISA for detect the galactomannan (GM) antigen. We systematically investigated the medical background that can be effective on the test results. The hospitalisation period was longer in proven/probable episodes when compared with no IA (P = 0.001) and possible episodes. With regard to duration of neutropenia, the differences between both proven/probable with no IA (P = 0.023) and possible with no IA (P = 0.002) were highly significant. Similarly, the rates of T cell suppressant therapy in group proven/probable and possible episodes were significantly higher than in no IA (P = 0.005). There are significant differences in the performance of GM and PCR-based tests among studies, and standardisation is required. Therefore, it can be useful to determine the effective factors on these tests. The use of larger volume of sera improved the performance of real-time PCR for detection of Aspergillus DNA in high-risk adult patients in the present study. Some host factors such as duration of neutropenia and administration of T cell suppressants related to the development of IA.

Novel tests for diagnosis of invasive aspergillosis in patients with underlying respiratory diseases

RATIONALE

Invasive pulmonary aspergillosis has been increasingly reported in nonneutropenic patients, including those with underlying respiratory diseases.

OBJECTIVES

We compared the diagnostic performances of galactomannan, 1,3-β-D-glucan, and Aspergillus-specific lateral-flow device tests with that of conventional culture by using bronchoalveolar lavage fluid samples from patients with underlying respiratory diseases.

METHODS

We analyzed 268 bronchoalveolar lavage samples from 221 patients with underlying respiratory diseases (and without hematologic malignancy or previous solid organ transplantation) that were collected for routine microbiological workup between February 2012 and May 2014 at the University Hospital of Graz, Austria. Invasive pulmonary aspergillosis was defined according to European Organization of Research and Treatment of Cancer/Mycoses Study Group criteria modified for patients with respiratory diseases.

MEASUREMENTS AND MAIN RESULTS

Thirty-one patients (14%) had probable or proven, 25 possible, and the remaining 165 patients no invasive pulmonary aspergillosis. Probable/proven aspergillosis was associated with a significantly higher (P = 0.034) 30-day mortality rate of 32%. Sensitivities, specificities, and diagnostic odd ratios differed markedly between galactomannan (cut-off 0.5: optical density index, 0.97, 0.81, 124.4; cut-off 1.0: 0.97, 0.93, 422.1; cut-off 3.0: 0.61, 0.99, 109.8), β-D-glucan (cut-off 80 pg/ml: 0.90, 0.42, 6.57; cut-off 200 pg/ml: 0.70, 0.61, 3.7), lateral-flow device tests (0.77, 0.92, 41.8), and mycological culture (0.29, 0.97, 14).

CONCLUSIONS

Probable or proven invasive pulmonary aspergillosis was diagnosed in 14% of our study population and associated with significantly higher 30-day mortality rates. Although the performance of β-D-glucan was limited by low specificity and that of mycological culture by low sensitivity, the Aspergillus lateral-flow device seems to be a promising alternative to galactomannan testing, which remains the diagnostic gold standard for aspergillosis. Clinical trial registered with www.clinicaltrials.gov (NCT 02058316).

Biomarkers for invasive aspergillosis: the challenges continue

The incidence of invasive aspergillosis (IA), an opportunistic infection in immunocompromised individuals, is rising, but its early diagnosis remains challenging and treatment options are limited. Hence there is an urgent need to improve existing diagnostic procedures as well as develop novel approaches. The clinical usefulness of galactomannan and β-d-glucan, widely used assays detecting cell-wall antigens of Aspergillus, is unclear and depends on clinicians' awareness of their practical limitations. This leaves room for new methods that utilise genomic, proteomic and metabolomics approaches as well as novel detection procedures, for example point-of-care lateral-flow devices. Each of these strategies has its own limitations and it is likely that a combination of methods will be required to achieve optimal performance for the diagnosis of IA and subsequent appropriate patient management.

SIMIFF study: Italian fungal registry of mold infections in hematological and non-hematological patients

Purpose

We compared the risk factors, the diagnostic tools and the outcome of filamentous fungal infections (FFIs) in hematological patients (HAEs) and non-hematological patients (non-HAEs).

Methods

Prospective surveillance (2009–2011) of proven and probable FFIs was implemented in 23 Italian hospitals.

Results

Out of 232 FFIs, 113 occurred in HAEs and 119 in non-HAEs. The most frequent infection was invasive aspergillosis (76.1 % for HAEs, 56.3 % for non-HAEs), and the localization was principally pulmonary (83.2 % for HAEs, 74.8 % for non-HAEs). Neutropenia was a risk factor for 89.4 % HAEs; the main underlying condition was corticosteroid treatment (52.9 %) for non-HAEs. The distribution of proven and probable FFIs was different in the two groups: proven FFIs occurred more frequently in non-HAEs, whereas probable FFIs were correlated with the HAEs. The sensitivity of the galactomannan assay was higher for HAEs than for non-HAEs (95.3 vs. 48.1 %). The overall mortality rate was 44.2 % among the HAEs and 35.3 % among the non-HAEs. The etiology influenced the patient outcomes: mucormycosis was associated with a high mortality rate (57.1 % for HAEs, 77.8 % for non-HAEs).

Conclusions

The epidemiological and clinical data for FFIs were not identical in the HAEs and non-HAEs. The differences should be considered to improve the management of FFIs according to the patients’ setting.