Invasive Pulmonary Aspergillosis in Patients with Chronic Obstructive Pulmonary Disease: An Emerging Fungal Disease

Prognostic factors and outcomes of invasive pulmonary aspergillosis, a retrospective hospital-based study

Objective

Invasive pulmonary aspergillosis (IPA) affects immunocompromised hosts and is associated with higher risks of respiratory failure and mortality. However, the clinical outcomes of different IPA types have not been identified.

Methods

Between September 2002 and May 2021, we retrospectively enrolled patients with IPA in Taichung Veterans General Hospital, Taiwan. Cases were classified as possible IPA, probable IPA, proven IPA, and putative IPA according to EORTC/MSGERC criteria and the AspICU algorithm. Risk factors of respiratory failure, kidney failure, and mortality were analyzed by logistic regression. A total of 3-year survival was assessed by the Kaplan-Meier method with log-rank test for post-hoc comparisons.

Results

We included 125 IPA patients (50: possible IPA, 47: probable IPA, 11: proven IPA, and 17: putative IPA). Comorbidities of liver cirrhosis and solid organ malignancy were risk factors for respiratory failure; diabetes mellitus and post-liver or kidney transplantation were related to kidney failure. Higher galactomannan (GM) test optical density index (ODI) in either serum or bronchoalveolar lavage fluid was associated with dismal outcomes. Probable IPA and putative IPA had lower 3-year respiratory failure-free survival compared to possible IPA. Probable IPA and putative IPA exhibited lower 3-year renal failure-free survival in comparison to possible IPA and proven IPA. Putative IPA had the lowest 3-year overall survival rates among the four IPA groups.

Conclusion

Patients with putative IPA had higher mortality rates than the possible, probable, or proven IPA groups. Therefore, a prompt diagnosis and timely treatment are warranted for patients with putative IPA.

Evaluation of (1,3)--d-glucan assay in diagnosis of invasive fungal infections with Aspergillus

Invasive fungal infections caused by Aspergillus are a significant problem in immunocompromised and critically ill patients and associated with increased morbidity and mortality. Early diagnosis of invasive aspergillosis is still a big clinical and diagnostic challenge. Conventional methods are not sensitive enough, and therefore, there is a need for rapid, more sensitive methods for early diagnosis of invasive fungal infections with Aspergillus. The aim of this study was to evaluate the diagnostic performance, sensitivity and specificity of serological panfungal (1,3)-b-D-glucan marker compared to conventional method for diagnosis of invasive fungal infections with Aspergillus. Material and methods: Specimens of 125 patients divided into 4 groups (group I - immune deficiency, group II - prolonged ICU stay, group III - chronic aspergillosis, group IV - cystic fibrosis), classified according to clinical diagnosis and EORTC/MSG criteria, were analyzed at the Institute of Microbiology and Parasitology, with conventional and serological methods, during a period of two years. Results: A total of 71 isolates of Aspergillus were confirmed in this study. Four isolates were recovered from bloodculture of patients with primary immune deficiency. With BAL culture, Aspergillus was detected in the group of chronic aspergillosis (63.33%), followed by the groups of cystic fibrosis (56.67%), primary immune deficiency (51.43%), and the group with prolonged ICU stay (43.33%). Sensitivity and specificity of BAL culture were: 64.29% and 100%, 59.09% and 100%, 54.55% and 12.5%, 100% and 54.17%, in I, II, III and IV group, respectively. In 79.1% (53/67) from positive BAL cultures in all groups, A. fumigatus was confirmed, of which, 32.1% (17/53) in group III, followed by group I – 26.42% (14/53) and group IV – 26.42% (14/53), and 15.1% (8/53) in group II. Other species confirmed in BAL were A. flavus 16.42% (11/67) and A.terreus 4.48% (3/67). Sensitivity and specificity of the serological panfungal (1,3)-b-D-glucan (BDG) marker were: 64.71% and 85.71%, 50% and 87.5%, 36.36% and 50%, in groups I, II and III, respectively. No positive findings of the panfungal (1,3)-b-D-glucan (BDG) marker were found in the group with cystic fibrosis. Conclusion: The results obtained in this study have demonstrated that a positive (1,3)-b-D-glucan assay highlights the value of this test as a diagnostic adjunct in the serodiagnosis of invasive fungal infections with Aspergillus, and along with the results from conventional mycological investigation, helped in reaching a timely antifungal treatment with a favorable clinical outcome.  

[Aspergillus-related respiratory conditions and COPD: Diagnostic challenges]

INTRODUCTION

The relations between chronic obstructive pulmonary disease (COPD) and respiratory diseases due to Aspergillus spp. are not well understood.

METHODS

We analysed a retrospective series of patients hospitalized with a diagnosis of COPD and respiratory disease due to Aspergillus. Patients were identified between 2010 and 2015 from the medico-administrative database of Cochin hospital, Paris. Historical, clinical, biological, microbiological and imaging data were collected and described. Diagnoses were reclassified based on reference definitions and classifications from the literature. Patients were classified according to the type of Aspergillus-related diseases and risk factors were described.

RESULTS

Forty patients were identified. Classifiable Aspergillus-related respiratory conditions were confirmed in 26 of them including 12 allergic bronchopulmonary aspergillosis (ABPA), 8 chronic pulmonary aspergillosis (CPA), 1 invasive pulmonary aspergillosis (IPA) and 3 diagnostic associations ABPA/CPA. Other respiratory comorbidities were present in all cases of CPA and immunodepression was recorded for semi-invasive and invasive forms. Finally, 16 patients could not be classified, among whom Aspergillus related lung disease was considered as likely in one-half.

CONCLUSION

The complexity of the diagnosis of pulmonary aspergillosis is related to its multiple types with sometimes unclear distinctions. Any type of pulmonary aspergillosis can be observed in patients with COPD, depending on associated risks factors. It would be helpful to establish specific classifications adapted to patients with COPD. This will require larger, prospective, multicentre studies.

Nanotechnology-based drug delivery systems for control of microbial biofilms: a review

Since the dawn of civilization, it has been understood that pathogenic microorganisms cause infectious conditions in humans, which at times, may prove fatal. Among the different virulent properties of microorganisms is their ability to form biofilms, which has been directly related to the development of chronic infections with increased disease severity. A problem in the elimination of such complex structures (biofilms) is resistance to the drugs that are currently used in clinical practice, and therefore, it becomes imperative to search for new compounds that have anti-biofilm activity. In this context, nanotechnology provides secure platforms for targeted delivery of drugs to treat numerous microbial infections that are caused by biofilms. Among the many applications of such nanotechnology-based drug delivery systems is their ability to enhance the bioactive potential of therapeutic agents. The present study reports the use of important nanoparticles, such as liposomes, microemulsions, cyclodextrins, solid lipid nanoparticles, polymeric nanoparticles, and metallic nanoparticles, in controlling microbial biofilms by targeted drug delivery. Such utilization of these nanosystems has led to a better understanding of their applications and their role in combating biofilms.

A prospective study of fungal biomarkers to improve management of invasive fungal diseases in a mixed specialty critical care unit

PURPOSE

The diagnosis of invasive fungal diseases (IFD) in critical care patients (CrCP) is difficult. The study investigated the performance of a set of biomarkers for diagnosis of IFD in a mixed specialty critical care unit (CrCU).

METHODS

A prospective observational study in patients receiving critical care for ≥7days was performed. Serum samples were tested for the presence of: (1-3) - β-d-glucan (BDG), galactomannan (GM), and Aspergillus fumigatus DNA. GM antigen detection was also performed on bronchoalveolar lavage (BAL) samples. The patients were classified using published definitions for IFD and a diagnostic algorithm for invasive pulmonary aspergillosis. Performance parameters of the assays were determined.

RESULTS

In patients with proven and probable IFD, the sensitivity, specificity, PPV and NPV of a single positive BDG were 63%, 83%, 65% and 83% respectively. Specificity increased to 86% with 2 consecutive positive results. The mean BDG value of patients with proven and probable IFD was significantly higher compared to those with fungal colonization and no IFD (p value<0.0001).

CONCLUSION

New diagnostic criteria which incorporate these biomarkers, in particular BDG, and host factors unique to critical care patients should enhance diagnosis of IFD and positively impact antifungal stewardship programs.

Development of Aspergillosis in a cohort of non-neutropenic, non-transplant patients colonised by Aspergillus spp

BACKGROUND

A previous study explored factors discriminating colonization and true infection among non-transplant, non-neutropenic patients with repeated Aspergillus spp. isolation from lower respiratory samples. The present study explored the evolution of patients with Aspergillus colonization in that study to determine the percentage of cases progressing to aspergillosis and time to development.

METHODS

Clinical records were retrospectively reviewed (for each patient from his end date in the past study) and data from all respiratory processes suffered by patients up to April 2015 were recorded. Comparisons of variables were performed between colonized patients that developed aspergillosis and those that did not. A Kaplan-Meier curve was used to describe time to development of aspergillosis in chronic obstructive pulmonary disease (COPD) patients for II-IV stages of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification.

RESULTS

Sixty seven colonized patients were followed, 12 of them (17.9%) developed aspergillosis. Diagnoses included six tracheobronchitis (4 invasive, 2 simple tracheobronchitis), four pulmonary disease (2 invasive pulmonary aspergillosis, 2 chronic pulmonary aspergillosis), one allergic bronchopulmonary aspergillosis and one pulmonary aspergilloma. Up to 47 (70.4%) of the study patients presented COPD. Among patients developing aspergillosis COPD was more frequent (100%) than among those that did not develop aspergillosis (35 out of 55; 63.6%) (p = 0.012), as well as GOLD IV patients were more frequent among COPD patients developing aspergillosis than among COPD patients that did not (50.0 vs. 26.1%, p = 0.046). Mean time to development of aspergillosis was 18.4 months (median: 8.5) with a wide range (1-58). Overtime, the percentage of patients developing aspergillosis was significantly higher among GOLD IV patients than among GOLD II-III patients (p = 0.032).

CONCLUSIONS

The high percentage of cases progressing to aspergillosis among colonized patients, especially among those with COPD (25.5%), stresses the importance of colonization as risk factor, and creates awareness of the possible change from colonization to invasive disease in GOLD IV patients.

Galactomannan in bronchoalveolar lavage fluid for diagnosis of invasive aspergillosis in non-hematological patients

BACKGROUND

The role of galactomannan (GM) in serum or bronchoalveolar lavage fluid (BALF) for the diagnosis of invasive pulmonary aspergillosis (IPA) has been extensively evaluated in hematological patients, however its performance in non-hematological patients is not well established.

METHODS

We performed a multicenter retrospective study in 3 university hospitals in Madrid, Spain between 2010 and 2014. The study population comprised patients with chronic obstructive pulmonary disease (COPD) and patients with immunosuppressive conditions in whom IPA was suspected and for whom BALF GM was available. Patients with hematological disorders were excluded.

RESULTS

A total of 188 patients (35 with COPD and 153 with immunosuppressive conditions) were analyzed, and 31 cases of IPA (proven or probable) were identified. The global sensitivity of BALF GM (optical density index [ODI] ≥ 1.0) was 77.4%; sensitivity was higher in patients with immunosuppressive conditions than in patients with COPD (81.8% vs 66.7%; p: 0.38). In COPD patients, the best performance was obtained for BALF GM (ODI ≥ 0.5), although sensitivity (88.9%) was similar to that of BALF fungal culture (88.9%). The sensitivity of GM in serum was very poor in both populations (36.4% and 11.6%, respectively).

CONCLUSIONS

In the present series, the diagnostic performance of BALF GM was good for IPA in non-hematological patients, especially in patients with immunosuppressive conditions.

Aspergillus colonization in patients with chronic obstructive pulmonary disease

Background and Purpose:

Chronic obstructive pulmonary disease (COPD) has been recognized as a risk factor for invasive aspergillosis. Airway colonization by Aspergillus species is a common feature of chronic pulmonary diseases. Nowadays, the incidence of COPD has increased in critically ill patients. The aim of the present study was to isolate and identify Aspergillus colonies in the respiratory tract of COPD patients.

Materials and Methods:

This study was performed on 50 COPD patients, who were aged above 18 years, and were in intensive care units of three hospitals in Sari, Iran, for at least six days. All the samples obtained from sputum, bronchoalveolar lavage, and tracheal aspirates were cultured for fungi each week. According to the conventional techniques, Aspergillus isolates were initially based on growth and standard morphological characteristics. To confirm the identification of grown Aspergillus, the partial beta-tubulin gene was sequenced using specific primers.

Results:

A total of 50 patients, who met our inclusion criteria, were enrolled in the study during 2012-14. The results showed that 27 (54%) and 23 (46%) of the participants were male and female, respectively. The majority of the patients developed dyspnea followed by hemoptysis, chest pain, and high fever. Corticosteroids and broad-spectrum antibacterial agents were administered to 75% and 80% of the patients, respectively. Based on the conventional and molecular approaches, A. fumigatus (seven cases; 43.7%), A. flavus (five cases; 31.2%), A. niger (one case; 6.2%), A. terreus (one case; 6.2%), A. orezea (one case; 6.2%), and A. tubingensis (one case; 6.2%) were recovered.

Conclusion:

Recovery of Aspergillus species from the respiratory tract of COPD patients with pneumonia indicates two possibilities: either colonization or invasive aspergillosis.

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).

The potential impact of the pulmonary microbiome on immunopathogenesis of Aspergillus-related lung disease

Aspergillosis is an infection or allergic response caused by fungi of the genus Aspergillus. The most common forms of aspergillosis are allergic bronchopulmonary aspergillosis, chronic pulmonary aspergillosis, and invasive pulmonary aspergillosis. Aspergillus also plays an important role in fungal sensitized asthma. Humans inhale Aspergillus spores every day and when the host is immunocompromised, Aspergillus spp. may cause severe pulmonary disease. There is increasing evidence that the microbiome plays a significant role in immune regulation, chronic inflammatory diseases, metabolism, and other physiological processes, including recovery from the effects of antibiotic treatment. Bacterial microbiome mediated resistance mechanisms probably play a major role in limiting fungal colonization of the lungs, and may therefore prevent humans from contracting Aspergillus-related diseases. In this perspective, we review this emerging area of research and discuss the role of the microbiome in aspergillosis, role of Aspergillus in the microbiome, and the influence of the microbiome on anti-Aspergillus host defense and its role in preventing aspergillosis.

Aspergillus infections in transplant and non-transplant surgical patients

BACKGROUND

Aspergillus infections are associated commonly with immunocompromised states, such as transplantation and hematologic malignant disease. Although Aspergillus infections among patients having surgery occur primarily in transplant recipients, they are found in non-recipients of transplants, and have a mortality rate similar to that seen among transplant recipients.

METHODS

We conducted a retrospective analysis of a prospective data base collected from 1996 to 2010, in which we identified patients with Aspergillus infections. We compared demographic data, co-morbidities, and outcomes in non-transplant patients with those in abdominal transplant recipients. Continuous data were evaluated with the Student t-test, and categorical data were evaluated through χ(2) analysis.

RESULTS

Twenty-three patients (11 transplant patients and 12 non-transplant patients) were identified as having had Aspergillus infections. The two groups were similar with regard to their demographics and co-morbidities, with the exceptions of their scores on the Acute Physiology and Chronic Health Evaluation II (APACHE II), of 23.6±8.1 points for transplant patients vs. 16.8±6.1 points for non-transplant patients (p=0.03); Simplified Acute Physiology Score (SAPS) of 16.6±8.3 points vs. 9.2±4.1 points, respectively (p=0.02); steroid use 91.0% vs. 25.0%, respectively (p=0.003); and percentage of infections acquired in the intensive care unit (ICU) 27.3% vs. 83.3%, respectively (p=0.01). The most common site of infection in both patient groups was the lung. The two groups showed no significant difference in the number of days from admission to treatment, hospital length of stay following treatment, or mortality.

CONCLUSIONS

Although Aspergillus infections among surgical patients have been associated historically with solid-organ transplantation, our data suggest that other patients may also be susceptible to such infections, especially those in an ICU who are deemed to be critically ill. This supports the idea that critically ill surgical patients exist in an immunocompromised state. Surgical intensivists should be familiar with the diagnosis and treatment of Aspergillus infections even in the absence of an active transplant program.

Aspergillus tracheobronchitis in critically ill patients with chronic obstructive pulmonary diseases

Aspergillus tracheobronchitis (ATB) is considered as an unusual form of invasive aspergillosis and has a fatal outcome. There is little current information on several aspects of chronic obstructive pulmonary diseases (COPD) complicated by ATB, the frequency of which is expected to increase in the coming years. In a prospective study of invasive bronchial-pulmonary aspergillosis (IBPA) in a critically ill COPD population, three proven cases of ATB were identified. The three new cases, combined with eight previously reported cases of COPD with ATB over a 30-year period (1983-2013), were analysed. Among 153 critically ill COPD patients admitted to the ICU, eight cases were complicated by ATB [23.5% of IBPA (8 of 34); and 5.2% of COPD (8 of 153)], and three cases were finally diagnosed as proven ATB by histopathological findings. Among the three new cases reported and the eight published cases, the overall mortality rate was 72.7% (8 of 11 cases), with a median of 11.5 days (range, 7-27 days) between admission to death. The mortality rate was significantly higher in patients with invasive pulmonary aspergillosis (IPA) [100% (8 of 8 patients)] than in patients without parenchyma invasion [0% (0 of 3 patient), P = 0.006]. Seven patients (77.8%) received systemic corticosteroid therapy and three patients (33.3%) inhaled corticosteroids before diagnosis with ATB. Dyspnoea resistant to corticosteroids (77.8%) was the most frequent symptom. The radiological manifestations progressed rapidly in three patients (75%) who had normal chest X-rays (CXRs) at admission. Pseudomembranous lesions were the most frequent form (54.5%) observed by bronchoscopy. Aspergillus fumigatus was the most frequently isolated pathogen (40%). ATB is an uncommon cause of exacerbation in approximately 5% of critically ill COPD patients admitted to the ICU, and may progress rapidly to IPA with a high mortality rate. Dyspnoea resistant to corticosteroids and appropriate antibiotics with a negative CXR should raise the suspicion of ATB. Early diagnosis of ATB is based on bronchoscopic examination and proven diagnosis maybe safely established with a bronchial mucous biopsy.

Aerially transmitted human fungal pathogens: what can we learn from metagenomics and comparative genomics?

In the last few decades, aerially transmitted human fungal pathogens have been increasingly recognized to impact the clinical course of chronic pulmonary diseases, such as asthma, cystic fibrosis or chronic obstructive pulmonary disease. Thanks to recent development of culture-free high-throughput sequencing methods, the metagenomic approaches are now appropriate to detect, identify and even quantify prokaryotic or eukaryotic microorganism communities inhabiting human respiratory tract and to access the complexity of even low-burden microbe communities that are likely to play a role in chronic pulmonary diseases. In this review, we explore how metagenomics and comparative genomics studies can alleviate fungal culture bottlenecks, improve our knowledge about fungal biology, lift the veil on cross-talks between host lung and fungal microbiota, and gain insights into the pathogenic impact of these aerially transmitted fungi that affect human beings. We reviewed metagenomic studies and comparative genomic analyses of carefully chosen microorganisms, and confirmed the usefulness of such approaches to better delineate biology and pathogenesis of aerially transmitted human fungal pathogens. Efforts to generate and efficiently analyze the enormous amount of data produced by such novel approaches have to be pursued, and will potentially provide the patients suffering from chronic pulmonary diseases with a better management. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

Therapeutic drug monitoring in voriconazole-associated hyponatremia

Voriconazole is a second generation triazole antifungal agent and the first choice therapy for invasive aspergillosis (IA). Although voriconazole may be associated with many adverse events, hyponatremia has been rarely reported which potentially could result in death. Therapeutic drug monitoring (TDM) and individualization of therapy by measuring voriconazole plasma concentrations improved the efficacy and safety in patients. We report the effect of TDM to adjust voriconazole dosage in a voriconazole-related hyponatremia patient.

Invasive Aspergillus infections in hospitalized patients with chronic lung disease

BACKGROUND

Although invasive pulmonary aspergillosis (IPA) is more prevalent in immunocompromised patients, critical care clinicians need to be aware of the occurrence of IPA in the nontraditional host, such as a patient with chronic lung disease. The purpose of this study was to describe the IPA patient with chronic lung disease and compare the data with that of immunocompromised patients.

METHODS

The records of 351 patients with Aspergillus were evaluated in this single-center, retrospective study for evidence and outcomes of IPA. The outcomes of 57 patients with chronic lung disease and 56 immunocompromised patients were compared. Patients with chronic lung disease were defined by one of the following descriptive terms: emphysema, asthma, idiopathic lung disease, bronchitis, bronchiectasis, sarcoid, or pulmonary leukostasis.

RESULTS

Baseline demographics were similar between the two groups. Patients with chronic lung disease were primarily defined by emphysema (61%) and asthma (18%), and immunocompromised patients primarily had malignancies (27%) and bone marrow transplants (14%). A higher proportion of patients with chronic lung disease had a diagnosis of IPA by bronchoalveolar lavage versus the immunocompromised group (P < 0.03). The major risk factors for IPA were found to be steroid use in the chronic lung disease group and neutropenia and prior surgical procedures in the immunocompromised group. Overall, 53% and 69% of chronic lung disease and immunocompromised patients were cured (P = 0.14); 55% of chronic lung patients and 47% of immunocompromised patients survived one month (P = 0.75).

CONCLUSION

Nontraditional patients with IPA, such as those with chronic lung disease, have outcomes and mortality similar to that in the more traditional immunocompromised population.

Airway and parenchymal manifestations of pulmonary aspergillosis

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

Bronchoalveolar lavage fluid galactomannan detection for diagnosis of invasive pulmonary aspergillosis in chronic obstructive pulmonary disease

Invasive pulmonary aspergillosis (IPA) is difficult to diagnose in chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate whether detection of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) might be a useful means of making the diagnosis. Patients with COPD and new pulmonary infiltrates were enrolled. BALF was collected for culture and detection of GM. Venous blood was also sampled for GM detection. Biopsy samples were obtained whenever possible. Eleven cases of IPA were diagnosed (three proven and eight probable); 80 controls without IPA diagnosed were recruited. At a GM cut-off of 0.5, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for diagnosing IPA were 90.9, 66.3, 27.0 and 98.1% in serum, and 90.9, 62.5, 25.0 and 98.0% in BALF, respectively. At a cut-off of 1.0, the specificity, PPV and NPV in BALF increased to 95.0, 71.4 and 98.7%; the sensitivity remained 90.9%. The sensitivity in serum was substantially lower than BALF (45.5% versus 90.9%). Receiver operating characteristic curve analysis identified an optimal BALF GM cut-off value of 1.25, with a sensitivity of 90.9% and a specificity of 96.3% for diagnosing IPA. At a relatively high cut-off value, BALF GM detection is a useful tool for the diagnosis of IPA in COPD. Besides piperacillin-tazobactam and amoxicillin-clavulanate, many other factors may also cause false-positive of GM detection in patients without IPA. Further work is needed to identify factors that might lead to false-positive or false-negative results.

Aspergillus bronchitis without significant immunocompromise

Aspergillus bronchitis is poorly understood and described. We extracted clinical data from more than 400 referred patients with persistent chest symptoms who did not fulfill criteria for allergic, chronic, or invasive aspergillosis. Symptomatic patients with a positive culture or real-time PCR for Aspergillus spp. were reviewed. Seventeen patients fulfilled the selected criteria. Fourteen were women, with a mean age of 57 years (range 39-76). Sixteen of the patients had productive cough, eight had voluminous tenacious sputum, and seven had recurrent chest infections. Eight patients had Medical Research Council dyspnea scores of 4-5; 12 had bronchiectasis; and 13 patients grew A. fumigatus, 3 A. niger, and 1 A. terreus. Twelve of the 17 patients (71%) had elevated Aspergillus IgG (47-137 mg/L, mean 89.2) and 5 (29%) had elevated Aspergillus precipitins. Six of 12 (50%) had a major response to antifungal therapy and five of 12 (42%) patients relapsed, requiring long-term therapy. Aspergillus bronchitis is a discrete clinical entity in patients with structural lung disease but who are not significantly immunocompromised. It is distinct from asymptomatic fungal colonization and other forms of aspergillosis, and may respond to antifungal therapy.

Laboratory diagnosis of invasive aspergillosis: from diagnosis to prediction of outcome

Invasive aspergillosis (IA), an infection caused by fungi in the genus Aspergillus, is seen in patients with immunological deficits, particularly acute leukaemia and stem cell transplantation, and has been associated with high rates of mortality in previous years. Diagnosing IA has long been problematic owing to the inability to culture the main causal agent A. fumigatus from blood. Microscopic examination and culture of respiratory tract specimens have lacked sensitivity, and biopsy tissue for histopathological examination is rarely obtainable. Thus, for many years there has been a great interest in nonculture-based techniques such as the detection of galactomannan, β -D-glucan, and DNA by PCR-based methods. Recent meta-analyses suggest that these approaches have broadly similar performance parameters in terms of sensitivity and specificity to diagnose IA. Improvements have been made in our understanding of the limitations of antigen assays and the standardisation of PCR-based DNA detection. Thus, in more recent years, the debate has focussed on how these assays can be incorporated into diagnostic strategies to maximise improvements in outcome whilst limiting unnecessary use of antifungal therapy. Furthermore, there is a current interest in applying these tests to monitor the effectiveness of therapy after diagnosis and predict clinical outcomes. The search for improved markers for the early and sensitive diagnosis of IA continues to be a challenge.

Repeated Aspergillus isolation in respiratory samples from non-immunocompromised patients not selected based on clinical diagnoses: colonisation or infection?

Background

Isolation of Aspergillus from lower respiratory samples is associated with colonisation in high percentage of cases, making it of unclear significance. This study explored factors associated with diagnosis (infection vs. colonisation), treatment (administration or not of antifungals) and prognosis (mortality) in non-transplant/non-neutropenic patients showing repeated isolation of Aspergillus from lower respiratory samples.

Methods

Records of adult patients (29 Spanish hospitals) presenting ≥2 respiratory cultures yielding Aspergillus were retrospectively reviewed and categorised as proven (histopathological confirmation) or probable aspergillosis (new respiratory signs/symptoms with suggestive chest imaging) or colonisation (symptoms not attributable to Aspergillus without dyspnoea exacerbation, bronchospasm or new infiltrates). Logistic regression models (step–wise) were performed using Aspergillosis (probable + proven), antifungal treatment and mortality as dependent variables. Significant (p < 0.001) models showing the highest R² were considered.

Results

A total of 245 patients were identified, 139 (56.7%) with Aspergillosis. Aspergillosis was associated (R² = 0.291) with ICU admission (OR = 2.82), congestive heart failure (OR = 2.39) and steroids pre-admission (OR = 2.19) as well as with cavitations in X-ray/CT scan (OR = 10.68), radiological worsening (OR = 5.22) and COPD exacerbations/need for O₂ interaction (OR = 3.52). Antifungals were administered to 79.1% patients with Aspergillosis (100% proven, 76.8% probable) and 29.2% colonised, with 69.5% patients receiving voriconazole alone or in combination. In colonised patients, administration of antifungals was associated with ICU admission at hospitalisation (OR = 12.38). In Aspergillosis patients its administration was positively associated (R² = 0.312) with bronchospasm (OR = 9.21) and days in ICU (OR = 1.82) and negatively with Gold III + IV (OR = 0.26), stroke (OR = 0.024) and quinolone treatment (OR = 0.29). Mortality was 78.6% in proven, 41.6% in probable and 12.3% in colonised patients, and was positively associated in Aspergillosis patients (R² = 0.290) with radiological worsening (OR = 3.04), APACHE-II (OR = 1.09) and number of antibiotics for treatment (OR = 1.51) and negatively with species other than A. fumigatus (OR = 0.14) and aspergillar tracheobronchitis (OR = 0.27).

Conclusions

Administration of antifungals was not always closely linked to the diagnostic categorisation (colonisation vs. Aspergillosis), being negatively associated with severe COPD (GOLD III + IV) and concomitant treatment with quinolones in patients with Aspergillosis, probably due to the similarity of signs/symptoms between this entity and pulmonary bacterial infections.

Clinical features of invasive pulmonary aspergillosis vs. colonization in COPD patients distributed by gold stage

OBJECTIVE

To explore clinical features of invasive pulmonary aspergillosis (IPA) vs. colonization among hospitalized COPD patients.

METHODS

Records of COPD patients with two respiratory cultures yielding Aspergillus were retrospectively reviewed. Cases categorized as proven/probable IPA or colonization was analyzed.

RESULTS

118 patients were identified: 70 (59.3%) colonized, 48 (40.7%) with IPA (42 probable, 6 proven). Higher percentage of IPA patients (vs. colonized) presented GOLD III + IV (77.1% vs. 57.1%, p = 0.025). IPA patients presented higher Charlson index (3.5 ± 2.5 vs. 2.6 ± 2.2, p = 0.027), higher rate of ICU admission (27.1% vs. 4.3%, p = 0.001) and worse prognosis (McCabe rapidly fatal category: 31.3% vs. 7.1%, p = 0.001). GOLD-I IPA patients presented risk factors other than COPD. Before hospitalization, 66.7% IPA and 28.6% colonized patients were taking steroids (p < 0.001). Antifungals were administered to 83.3% IPA and 21.4% colonized patients (p < 0.001). Mortality was higher among IPA vs. colonized patients, both in global (58.3% vs. 10.0%, p < 0.001), GOLD-I (75.0% vs. 10.0%, p = 0.041), GOLD-II (42.9% vs. 5.0%, p = 0.042) and GOLD-III patients (54.2% vs. 0.0%, p < 0.001), but not in GOLD-IV patients (69.2% vs. 31.3%, p = 0.066).

CONCLUSIONS

IPA should be suspected not only in GOLD-III and GOLD-IV COPD patients, with higher mortality in IPA vs. colonized patients for GOLD-II and -III COPD patients.

Role of galactomannan determinations in bronchoalveolar lavage fluid samples from critically ill patients with chronic obstructive pulmonary disease for the diagnosis of invasive pulmonary aspergillosis: a prospective study

INTRODUCTION

Critically ill chronic obstructive pulmonary disease (COPD) patients are at particular risk of invasive pulmonary aspergillosis (IPA). Our aims were to determine whether bronchoalveolar lavage fluid (BALF) galactomannan (GM) has a higher sensitivity and specificity than serum GM or lower respiratory tract (LRT) sample culture. Furthermore, we aimed to investigate what the optimal cut-off value would be for BALF GM.

METHODS

In this prospective single-center study, BALF and serum samples were collected from critically ill COPD patients on the first day of their intensive care unit admission.

RESULTS

Of 50 critically ill COPD patients admitted, BALF and serum samples were collected in 34 patients. According to the receiver operating characteristics (ROC) curve, an optical density (OD) ratio of 0.8 was chosen as the cut-off value for GM in BALF. Compared to serum GM and LRT Aspergillus isolation, BALF GM yield a better sensitivity, specificity, positive and negative predictive values of 88.9%, 100%, 100% and 94.4%, respectively. Areas under the ROC curve were 0.912 (95%CI, 0.733 to 0.985) for BALF GM, and 0.879 (95%CI, 0.691 to 0.972) for serum GM results from the first day of ICU admission. Pairwise comparison of ROC curves showed P = 0.738. The OD ratio of BALF GM in IPA patients were significantly higher than those of non-IPA patients (2.88 ± 2.09 versus 0.49 ± 0.19, P = 0.009), and the OD ratio of BALF GM was significantly higher than serum GM in IPA patients (2.88 ± 2.09 versus 0.87 ± 0.47, P = 0.023). Positive BALF GM was seen earlier than LRT secretion culture (1 day versus 3.8 days).

CONCLUSIONS

Compared to serum GM and LRT Aspergillus isolation, BALF GM seems to have a better sensitivity in the diagnosis of IPA in critically ill COPD patients. The ROC curve suggests a possible cut-off value of 0.8 for GM from BALF specimens in critically ill COPD patients.