Utility of Serum and Bronchoalveolar Lavage Fluid Galactomannan in Diagnosis of Chronic Pulmonary Aspergillosis

The value of metagenomic next-generation sequencing with different nucleic acid extracting methods of cell-free DNA or whole-cell DNA in the diagnosis of non-neutropenic pulmonary aspergillosis

Purpose

Metagenomic next-generation sequencing(mNGS) is a novel molecular diagnostic technique. For nucleic acid extraction methods, both whole-cell DNA (wcDNA) and cell-free DNA (cfDNA) are widely applied with the sample of bronchoalveolar lavage fluid (BALF). We aim to evaluate the clinical value of mNGS with cfDNA and mNGS with wcDNA for the detection of BALF pathogens in non-neutropenic pulmonary aspergillosis.

Methods

mNGS with BALF-cfDNA, BALF-wcDNA and conventional microbiological tests (CMTs) were performed in suspected non-neutropenic pulmonary aspergillosis. The diagnostic value of different assays for pulmonary aspergillosis was compared.

Results

BALF-mNGS (cfDNA, wcDNA) outperformed CMTs in terms of microorganisms detection. Receiver operating characteristic (ROC) analysis indicated BALF-mNGS (cfDNA, wcDNA) was superior to culture and BALF-GM. Combination diagnosis of either positive for BALF-mNGS (cfDNA, wcDNA) or CMTs is more sensitive than CMTs alone in the diagnosis of pulmonary aspergillosis (BALF-cfDNA+CMTs/BALF-wcDNA+CMTs vs. CMTs: ROC analysis: 0.813 vs.0.66, P=0.0142/0.796 vs.0.66, P=0.0244; Sensitivity: 89.47% vs. 47.37%, P=0.008/84.21% vs. 47.37%, P=0.016). BALF-cfDNA showed a significantly greater reads per million (RPM) than BALF-wcDNA. The area under the ROC curve (AUC) for RPM of Aspergillus detected by BALF-cfDNA, used to predict "True positive" pulmonary aspergillosis patients, was 0.779, with a cut-off value greater than 4.5.

Conclusion

We propose that the incorporation of BALF-mNGS (cfDNA, wcDNA) with CMTs improves diagnostic precision in the identification of non-neutropenic pulmonary aspergillosis when compared to CMTs alone. BALF-cfDNA outperforms BALF-wcDNA in clinical value.

A novel indirect ELISA for serodiagnosis of mucormycosis using antigens from Rhizopus arrhizus

BACKGROUND

Due to a delay in diagnosis by conventional techniques and high mortality, the development of a standardised and rapid non-culture-based technique is an unmet need in pulmonary, gastrointestinal, and disseminated forms of mucormycosis. Though limited studies have been conducted for molecular diagnosis, there are no established serologic tests for this highly fatal infection.

OBJECTIVE

To develop and evaluate an indirect in-house enzyme-linked immunosorbent assay (ELISA) utilising antigens of Rhizopus arrhizus for detecting anti-Rhizopus antibodies (IgG and IgM) in sera of patients with mucormycosis.

METHODS

We extracted both secretory and mycelial Rhizopus antigens using standardised protocols. Bradford assay was used for protein quantification. We then standardised an indirect ELISA using R. arrhizus mycelial and secretory antigens (10.0 μg/mL in bicarbonate buffer pH 9.2) for detecting anti-Rhizopus IgG and IgM antibodies in patient sera. We included patients with mucormycosis, other fungal infections, and healthy controls. Antibody index value (E-value) was calculated for each patient sample.

RESULTS

Asparagine broth culture filtrate utilising 85% ammonium sulphate salt fractionation and mycelial homogenate grown in yeast extract peptone dextrose (YPD) broth precipitated with trichloroacetic acid (TCA) yielded a large amount of good-quality protein for the assay. We included 55 patients with mucormycosis (rhino-orbito-cerebral mucormycosis [ROCM, n = 39], pulmonary [n = 15], gastrointestinal [n = 1]), 24 with other fungal infections (probable aspergillosis [n = 14], candidiasis [n = 10]), and healthy controls (n = 16). The sensitivity of the antibody test for diagnosing mucormycosis ranged from 83.6-92.7% for IgG and 72.7-87.3% for IgM, with a specificity of 91.7-92.5% for IgG and 80-82.5% for IgM. The sera from patients with other fungal infections and healthy individuals did not show significant cross-reactivity.

CONCLUSION

The detection of anti-Rhizopus IgG antibody performed significantly better in comparison to IgM-based ELISA for diagnosing both ROCM (sensitivity of 84.6% vs. 69.2%) and pulmonary cases (86.6% vs. 80.0%). More extensive studies are required to confirm our findings.

Innate and adaptive immune responses in subjects with CPA secondary to post-pulmonary tuberculosis lung abnormalities

BACKGROUND

Post-tuberculosis lung abnormality (PTLA) is the most common risk factor for chronic pulmonary aspergillosis (CPA), and 14%-25% of the subjects with PTLA develop CPA. The pathogenesis and the host immune response in subjects with PTLA who develop CPA need to be better understood.

METHODS

We prospectively compared the innate and adaptive immune responses mounted by patients of PTLA with or without CPA (controls). We studied the neutrophil oxidative burst (by dihydrorhodamine 123 test), classic (serum C3 and C4 levels) and alternative (mannose-binding lectin [MBL] protein levels) complement pathway, serum immunoglobulins (IgG, IgM and IgA), B and T lymphocytes and their subsets in subjects with PTLA with or without CPA.

RESULTS

We included 111 subjects (58 CPA and 53 controls) in the current study. The mean ± SD age of the study population was 42.6 ± 15.7 years. The cases and controls were matched for age, gender distribution and body weight. Subjects with CPA had impaired neutrophil oxidative burst, lower memory T lymphocytes and impaired Th-1 immune response (lower Th-1 lymphocytes) than controls. We found no significant difference between the two groups in the serum complement levels, MBL levels, B-cell subsets and other T lymphocyte subsets.

CONCLUSION

Subjects with CPA secondary to PTLA have impaired neutrophil oxidative burst and a lower Th-1 response than controls.

Incidence and prevalence of chronic pulmonary aspergillosis in patients with post-tuberculosis lung abnormality: Results from a community survey in North India

BACKGROUND

Post-tuberculosis lung abnormality (PTLA) is the most common risk factor for developing chronic pulmonary aspergillosis (CPA). However, the prevalence and incidence of CPA in PTLA patients in India remain unknown.

OBJECTIVES

We aimed to ascertain the incidence and prevalence of CPA in subjects with PTLA.

METHODS

We identified a cohort of pulmonary tuberculosis who completed anti-tuberculosis therapy (ATT) before November 2019 from the records of the 12 tuberculosis treatment centers attached to the national program. We recorded the clinical and demographic details. We performed computed tomography (CT) of the chest and estimated serum A. fumigatus-specific IgG. We categorised subjects as PTLA with or without CPA using a composite of clinical, radiological, and microbiological features. We resurveyed the subjects at 6 months (or earlier) for the presence of new symptoms. We calculated the prevalence and the incidence rate (per 100-person years) of CPA.

RESULTS

We included 117 subjects with PTLA, with a median of 3 years after ATT completion. Eleven subjects had CPA in the initial survey, and one additional case developed CPA during the second survey. The prevalence of CPA in PTLA subjects was 10.3% (12/117). The total observation period was 286.7 person-years. The median (interquartile range) time to develop CPA after ATT completion was 12.5 (5-36.7) months. We found the CPA incidence rate (95% confidence interval) of 4.2 (1.8-6.5) per 100-person years.

CONCLUSION

Chronic pulmonary aspergillosis complicates 10% of PTLA subjects after successful outcomes with ATT. Four new CPA cases may develop per 100-persons years of observation after ATT completion. We suggest screening patients with PTLA who develop new symptoms for CPA.

Burden, clinical features, and outcomes of post-tuberculosis chronic obstructive lung diseases

PURPOSE OF REVIEW

Post-tuberculosis lung disease (PTLD) is an increasingly recognized and debilitating consequence of pulmonary tuberculosis (PTB). In this review, we provide a comprehensive overview of PTLD with airflow obstruction (PTLD-AFO), focusing on its burden, pathophysiology, clinical manifestations, diagnostic methods, and management strategies.

RECENT FINDINGS

The relationship between PTLD and airflow obstruction is complex and multifactorial. Approximately 60% of the patients with PTLD have some spirometric abnormality. Obstruction is documented in 18-22% of PTLD patients. The host susceptibility and host response to mycobacterium drive the pathogenic mechanism of PTLD. A balance between inflammatory, anti-inflammatory, and fibrotic pathways decides whether an individual with PTB would have PTLD after microbiological cure. An obstructive abnormality in PTLD-AFO is primarily due to destruction of bronchial walls, aberrant healing, and reduction of mucosal glands. The most common finding on computed tomography (CT) of thorax in patients with PTLD-AFO is bronchiectasis and cavitation. Therefore, the 'Cole's vicious vortex' described in bronchiectasis applies to PTLD. A multidisciplinary approach is required for diagnosis and treatment. The disability-adjusted life-years (DALYs) attributed to PTLD represent about 50% of the total estimated burden of DALYs due to tuberculosis (TB). Patients with PTLD require comprehensive care that includes psychosocial support, pulmonary rehabilitation, and vaccination against respiratory pathogens. In the absence of trials evaluating different treatments for PTLD-AFO, therapy is primarily symptomatic.

SUMMARY

PTLD with airflow obstruction has considerable burden and causes a significant morbidity and mortality. However, many aspects of PTLD-AFO still need to be answered. Studies are required to evaluate different phenotypes, especially concerning Aspergillus -related complications. The treatment should be personalized based on the predominant phenotype of airflow obstruction. Extensive studies to understand the exact burden, pathogenesis, and treatment of PTBLD-AFO are needed.

Chronic Pulmonary Aspergillosis: Clinical Presentation and Management

Chronic pulmonary aspergillosis (CPA) refers to a number of clinical syndromes resulting from the presence and local proliferation of Aspergillus organisms in the lungs of patients with chronic lung disease. CPA is more common than was realized two decades ago. Recognition remains poor, despite recent studies from many countries highlighting the high prevalence in at-risk populations. In low- and middle-income countries, CPA may be misdiagnosed and treated as tuberculosis (TB). In addition, CPA may develop following successful TB treatment. The coronavirus disease pandemic has resulted in significant disruption to provision of TB care, likely leading to more extensive lung damage, which could increase the risk for CPA.Although CPA refers to various syndromes, the classic presentation is that of chronic cavitary pulmonary aspergillosis, which manifests as one or more progressive cavities with or without a fungal ball, accompanied by systemic and respiratory symptoms for at least 3 months. Diagnosis relies on Aspergillus immunoglobulin G in serum, as sputum culture lacks sensitivity. Differential diagnosis includes mycobacterial infection, bacterial lung abscess or necrotizing pneumonia, lung cancer, and endemic fungi.The aim of antifungal treatment in CPA is to improve symptoms and quality of life, and to halt progression, and possibly reverse radiological changes. Current recommendations suggest treatment for 6 months, although in practice many patients remain on long-term treatment. Improvement may manifest as weight gain and improvement of symptoms such as productive cough, hemoptysis, and fatigue. Surgical management should be considered in cases of diagnostic uncertainty, in significant hemoptysis, and when there is concern for lack of response to therapy. Itraconazole and voriconazole are the first-line azoles, with more experience now accumulating with posaconazole and isavuconazole. Side effects are frequent and careful monitoring including therapeutic drug monitoring is essential. Intravenous antifungals such as echinocandins and amphotericin B are used in cases of azole intolerance or resistance, which often develop on treatment. Relapse is seen after completion of antifungal therapy in around 20% of cases, mostly in bilateral, high-burden disease.Several research priorities have been identified, including characterization of immune defects and genetic variants linked to CPA, pathogenetic mechanisms of Aspergillus adaptation in the lung environment, the contribution of non-fumigatus Aspergillus species, and the role of new antifungal agents, immunotherapy, and combination therapy.

Microbiological Diagnosis of Pulmonary Aspergillus Infections

As microbiological tests play an important role in our diagnostic algorithms and clinical approach towards patients at-risk for pulmonary aspergillosis, a good knowledge of the diagnostic possibilities and especially their limitations is extremely important. In this review, we aim to reflect critically on the available microbiological diagnostic modalities for diagnosis of pulmonary aspergillosis and formulate some future prospects. Timely start of adequate antifungal treatment leads to a better patient outcome, but overuse of antifungals should be avoided. Current diagnostic possibilities are expanding, and are mainly driven by enzyme immunoassays and lateral flow device tests for the detection of Aspergillus antigens. Most of these tests are directed towards similar antigens, but new antibodies towards different targets are under development. For chronic forms of pulmonary aspergillosis, anti-Aspergillus IgG antibodies and precipitins remain the cornerstone. More studies on the possibilities and limitations of molecular testing including targeting resistance markers are ongoing. Also, metagenomic next-generation sequencing is expanding our future possibilities. It remains important to combine different test results and interpret them in the appropriate clinical context to improve performance. Test performances may differ according to the patient population and test results may be influenced by timing, the tested matrix, and prophylactic and empiric antifungal therapy. Despite the increasing armamentarium, a simple blood or urine test for the diagnosis of aspergillosis in all patient populations at-risk is still lacking. Research on diagnostic tools is broadening from a pathogen focus on biomarkers related to the patient and its immune system.

Chronic pulmonary aspergillosis: comprehensive insights into epidemiology, treatment, and unresolved challenges

Chronic pulmonary aspergillosis (CPA) is a challenging respiratory infection caused by the environmental fungus Aspergillus. CPA has a poor prognosis, with reported 1-year mortality rates ranging from 7% to 32% and 5-year mortality rates ranging from 38% to 52%. A comprehensive understanding of the pathogen, pathophysiology, risk factors, diagnosis, surgery, hemoptysis treatment, pharmacological therapy, and prognosis is essential to manage CPA effectively. In particular, Aspergillus drug resistance and cryptic species pose significant challenges. CPA lacks tissue invasion and has specific features such as aspergilloma. The most critical risk factor for the development of CPA is pulmonary cavitation. Diagnostic approaches vary by CPA subtype, with computed tomography (CT) imaging and Aspergillus IgG antibodies being key. Treatment strategies include surgery, hemoptysis management, and antifungal therapy. Surgery is the curative option. However, reported postoperative mortality rates range from 0% to 5% and complications range from 11% to 63%. Simple aspergilloma generally has a low postoperative mortality rate, making surgery the first choice. Hemoptysis, observed in 50% of CPA patients, is a significant symptom and can be life-threatening. Bronchial artery embolization achieves hemostasis in 64% to 100% of cases, but 50% experience recurrent hemoptysis. The efficacy of antifungal therapy for CPA varies, with itraconazole reported to be 43-76%, voriconazole 32-80%, posaconazole 44-61%, isavuconazole 82.7%, echinocandins 42-77%, and liposomal amphotericin B 52-73%. Combinatorial treatments such as bronchoscopic triazole administration, inhalation, or direct injection of amphotericin B at the site of infection also show efficacy. A treatment duration of more than 6 months is recommended, with better efficacy reported for periods of more than 1 year. In anticipation of improvements in CPA management, ongoing advances in basic and clinical research are expected to contribute to the future of CPA management.

Effect of volume of instillate on the diagnostic utility of bronchoalveolar lavage galactomannan in patients with suspected chronic pulmonary aspergillosis-A pilot study

BACKGROUND

Bronchoalveolar lavage (BAL) galactomannan (GM) is commonly used to diagnose Aspergillus-related lung diseases. However, unlike serum GM, which is measured in undiluted blood, BAL-GM is estimated using variable aliquots and cumulative volume of instillates during bronchoscopy.

OBJECTIVE

Since different studies have reported varying diagnostic accuracy and cut-offs for BAL-GM in CPA, we hypothesized that the total volume of instillate and 'order/label' of aliquots significantly affects the BAL-GM values, which was evaluated as part of this study.

PATIENTS & METHODS

We obtained 250 BAL samples from 50 patients (five from each) with suspected chronic pulmonary aspergillosis. BAL fluid was collected after instilling sequential volumes of 40 mL of normal saline each for the first four labels and a fifth label was prepared by mixing 1 mL from each of the previous labels. The GM level of each label was measured by PLATELIA™ ASPERGILLUS Ag enzyme immunoassay. This study measured the discordance, level of agreement, diagnostic characteristics (sensitivity, specificity and AUROC) and best cut-offs for BAL-GM in the different aliquots of lavage fluid.

RESULTS

The study population, classified into CPA (28%) and non-CPA (72%) groups, based on ERS/ESCMID criteria (excluding BAL-GM) were not different with respect to clinico-radiological characteristics. The discordance of BAL-GM positivity (using a cut-off of >1) between the serial labels for the same patient ranged between 10% and 22%, while the discordance between classification using BAL-GM positivity (using a cut-off of ≥1) and clinic-radio-microbiological classification ranged between 18% and 30%. The level of agreement for serial labels was at best fair (<0.6 for all except one 'label'). The AUROC for the serial samples ranged between 0.595 and 0.702, with the '40 mL and the 'mix' samples performing the best. The best BAL-GM cut-off also showed significant variation between serial labels of varying dilutions (Range:1.01 - 4.26).

INTERPRETATION

This study highlights the variation in BAL-GM measured and the 'positivity' between different 'labels' of aliquots of BAL, with the first aliquot and the mixed sample showing the best performances for diagnosis of CPA. Future studies should attempt to 'standardise' the instilled volume for BAL-GM estimation to standardise the diagnostic yield.

Analytical and clinical validation of multiplex droplet digital PCR assay for detecting pathogenic fungal infection in lungs

Pulmonary invasive fungal infection in immunocompromised hosts is difficult to diagnose, and current tools for diagnosis or monitoring of response to antifungal treatments have inherent limitations. Droplet digital PCR (ddPCR) has emerged as a promising tool for pulmonary pathogen detection with high sensitivity. This study presents a novel ddPCR panel for rapid and sensitive identification of pulmonary fungal pathogens. First, a ddPCR method for detecting three fungal genera, including Pneumocystis, Aspergillus, and Cryptococcus, was established and evaluated. Then, the clinical validation performance of ddPCR was compared with that of qPCR using 170 specimens, and the 6 specimens with inconsistent results were further verified by metagenomics next-generation sequencing, which yielded results consistent with the ddPCR findings. Finally, the area under the ROC curve (AUC) was used to evaluate the efficiency of ddPCR. While the qPCR identified 16 (9.41%) cases of Aspergillus and 6 (3.53%) cases of Pneumocystis, ddPCR detected 20 (11.76%) Aspergillus cases and 8 (4.71%) Pneumocystis cases. The AUC for Aspergillus, Cryptococcus, and Pneumocystis was 0.974, 0.998, and 0.975, respectively. These findings demonstrated that the ddPCR assay is a highly sensitive method for identifying pathogens responsible for invasive fungal pulmonary infections, and is a promising tool for early diagnosis.      .

The Utility of Galactomannan and Polymerase Chain Reaction Assays in Bronchoalveolar Lavage for Diagnosis of Chronic Pulmonary Aspergillosis

The diagnosis of chronic pulmonary aspergillosis (CPA) is established by combined clinic-radio-microbiological criteria. Out of the different microbiological criteria, a positive serology for Aspergillus-specific IgG levels is the cornerstone of diagnosis. Alternatively, other microbiological evidence are sometimes sought viz., positive Aspergillus antigen (broncho-alveolar lavage fluid, i.e., BALF galactomannan ≥ 1.0), histopathological demonstration of the fungi following lung biopsy or resection, demonstration of hyaline septate hyphae in direct microscopy resembling Aspergillus spp. or its growth on a respiratory specimen. However, the exact roles of BALF- GM and the newer BALF-PCR have not been confirmed by studies till date. This study enrolled 210 patients with suspected CPA. Of the participants, 88 patients met the criteria for CPA, whereas 122 patients had an alternative diagnosis. The sensitivity-specificity of AsperGenius® PCR and "in-house" PCR were 52.27(36.69-67.54) %-33.78 (23.19-45.72) % and 36.36 (22.41-52.23) %-39.19 (28.04-51.23) % respectively. The sensitivity/specificity of BALF (> 1.0) and serum galactomannan (> 1.0) were 46.55% (33.34-60.13)/64.08% (54.03-73.3) and 29.82% (22.05-37.6)/86.84% (81.1-92.59) respectively. The optimal cut-off values for BALF-Galactomannan and serum galactomannan in diagnosing CPA were found to be 0.69 (sensitivity: 64%; specificity: 53%) and 0.458 (sensitivity: 67%; specificity: 64%) respectively. This results of this study suggests that Aspergillus PCR from BAL may not be a good "rule-in" test for diagnosing CPA. While the performances of GM in BAL and serum may be better than PCR, it should be best used in conjunction with other clinical, radiological, and other microbiological characteristics.

Diagnosis of Chronic Pulmonary Aspergillosis: Clinical, Radiological or Laboratory?

Chronic pulmonary aspergillosis (CPA) is a chronic progressive lung disease associated with a poor prognosis and a 5-year mortality rate of approximately 40-50%. The disease is characterized by slowly progressive destruction of the lung parenchyma, in the form of multiple cavities, nodules, infiltrates or fibrosis. CPA can be challenging to diagnose due to its non-specific symptoms and similarities with other respiratory conditions combined with the poor awareness of the medical community about the disease. This can result in delayed treatment even for years and worsening of the patient's condition. Serological tests certainly play a significant role in diagnosing CPA but cannot be interpreted without radiological confirmation of CPA. Although many data are published on this hot topic, there is yet no single definitive test for diagnosing CPA, and a multidisciplinary approach which involves a combination of clinical picture, radiological findings, microbiological results and exclusion of other mimicking diseases, is essential for the accurate diagnosis of CPA.

Role of C-Reactive Protein and Erythrocyte Sedimentation Rate in the Diagnosis and Monitoring of Treatment Response in Treatment Naïve Subjects with Chronic Pulmonary Aspergillosis

PURPOSE

The role of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) for diagnosing chronic pulmonary aspergillosis (CPA) remains unknown. Herein, we investigate the diagnostic performance of serum ESR and CRP in CPA.

METHODS

We retrospectively analyzed the data of treatment-naïve subjects with CPA and diseased controls (post-tuberculosis lung disease on CT thorax). We treated CPA subjects with six months of oral itraconazole. Our primary objective was to evaluate the sensitivity and specificity of ESR and CRP in diagnosing CPA. The key secondary objective was to study the change in the inflammatory markers with treatment.

RESULTS

We included 434 subjects and 20 diseased controls. The sensitivity and specificity of ESR (n = 434) and CRP (at cut-off value of 10 mg/L, n = 308) in diagnosing CPA were 42.9% and 65%, and 52.3% and 65%, respectively. Both ESR and CRP had erratic trend following treatment. ESR and CRP declined or remained stable in approximately 60% of subjects but increased in approximately 40% of the subjects despite treatment.

CONCLUSION

Serum CRP and ESR have limited utility in diagnosing and following subjects with CPA.

Characterization of Treatment Response Outcomes in Chronic Pulmonary Aspergillosis: CPAnet Definitions Versus the Existing Criteria

BACKGROUND

The chronic pulmonary aspergillosis network (CPAnet) has recently proposed definitions for treatment outcomes in CPA. However, these definitions need to be validated. Herein, we evaluate the agreement between the existing and the CPAnet definitions for response assessment.

METHODS

We enrolled consecutive treatment-naïve CPA subjects (between January 2021 and June 2021) who received six months of itraconazole therapy and followed them for an additional six months after treatment discontinuation. We retrospectively applied the CPAnet criteria and compared the agreement between the existing and the CPAnet criteria for response assessment (primary objective). We also assessed if adding weight loss (> 5% from baseline) as a component improved the performance of the CPAnet criteria.

RESULTS

We included 43 (mean age, 47.4 years) CPA subjects. The existing and the CPAnet criteria categorized 29 (67.4%) and 30 (69.8%) subjects as treatment success, respectively, at treatment completion. There was substantial (kappa = 0.73; p < 0.0001) agreement between the two definitions. However, both criteria did not identify eight subjects requiring treatment re-initiation within three months. There was an increment in the sensitivity of both criteria (by 36%) for identifying treatment failure after incorporating ≥ 5% weight loss as an element of worsening.

CONCLUSION

The CPAnet definitions correctly categorized treatment outcomes in most cases of CPA. The addition of weight change would further enhance the performance of the CPAnet treatment outcome definitions.

Systematic review and meta-analysis of galactomannan antigen testing in serum and bronchoalveolar lavage for the diagnosis of chronic pulmonary aspergillosis: defining a cutoff

BACKGROUND

A clear cutoff value of galactomannan (GM) has not been established for chronic pulmonary aspergillosis (CPA) and is frequently extrapolated from invasive pulmonary aspergillosis. We performed a systematic review and meta-analysis to evaluate the diagnostic performance of serum and bronchoalveolar lavage (BAL) GM, and to propose a cutoff.

METHODS

We extracted from the studies the cutoff of serum or/and BAL GM associated with true positives, false positives, true negatives, and false negatives. We performed a multi-cutoff model and a non-parametric random effect model. We estimated the optimal cutoff and the area under the curve (AUC) for GM in serum and BAL samples.

RESULTS

Nine studies from 1999 to 2021 were included. Overall, the optimal cutoff of serum GM was 0.96 with a sensitivity of 0.29 (95%CI: 0.14-0.51); specificity of 0.88 (95%CI: 0.73-0.95); and AUC of 0.529 (with a CI: [0.415-0.682] [0.307-0.713]). The AUC for the non-parametric ROC model was 0.631. For BAL GM the cutoff was 0.67 with a sensitivity of 0.68 (95%CI: 0.51-0.82), specificity of 0.84 (95%CI: 0.70-0.92), and AUC of 0.814 (with a CI: [0.696-0.895] [0.733-0.881]). The AUC for the non-parametric model was 0.789.

CONCLUSION

The diagnosis of CPA requires the assessment of a combination of mycological and serological factors, as no single serum and/or BAL GM antigen test is adequate. BAL GM performed better than serum, with better sensitivity and excellent accuracy.

Identification of distinct immunophenotypes in chronic pulmonary aspergillosis using cluster analysis

BACKGROUND

Whether chronic pulmonary aspergillosis (CPA) has different immunophenotypes remains unknown.

OBJECTIVE

To identify different CPA immunophenotypes using cluster analysis.

METHODS

We used a subject-centred multivariate clustering approach without prior assumptions to identify CPA phenotypes. We retrospectively included the data of treatment-naïve subjects with CPA and excluded subjects with asthma and allergic bronchopulmonary aspergillosis (ABPA). We performed a scalable two-step cluster analysis using the log-likelihood distance measures to identify CPA phenotypes based on the blood immunological profile (total IgE, eosinophil count and Aspergillus-specific IgE and IgG).

RESULTS

We included 351 CPA subjects and found two clusters. Cluster 2 (n = 118) had significantly higher serum total IgE, peripheral blood eosinophil count, and serum A. fumigatus-specific IgE and IgG than cluster 1 (n = 233). Cluster 2 subjects had a lower FEV1:FVC ratio on spirometry and were more likely to have a fungal ball (88 [74.6%] vs. 145 (62.2%), p = .023) on the CT thorax than cluster 1. After treatment discontinuation, cluster 2 had a longer median (interquartile range) time to relapse than cluster 1 (11.5 [7.3-27.4] vs. 4 [1.1-8.9] months, p = .005).

CONCLUSION

We identified two distinct CPA phenotypes, type-2 dominant and non-type-2, with different clinical and radiological findings and treatment outcomes. Future studies should confirm our findings and investigate different treatment strategies based on CPA phenotypes.

Role of serum procalcitonin in the diagnosis and monitoring of treatment response in treatment-naïve subjects with chronic pulmonary aspergillosis

Background

Interferon-gamma (IFN-γ) down-regulates plasma procalcitonin (PCT), marker of inflammation. Chronic pulmonary aspergillosis (CPA) is associated with low IFN-γ levels. Thus, plasma PCT may be elevated in CPA and could have a role in diagnosing and monitoring treatment response in CPA. Herein, we investigate the diagnostic performance of plasma PCT in CPA.

Methods

We extracted the demographic, clinical, radiological, treatment outcomes, and plasma PCT levels of CPA subjects and controls (previously treated pulmonary tuberculosis with radiological abnormalities on CT chest [diseased controls] and treatment naïve active pulmonary tuberculosis [PTB]). We treated CPA subjects with six months of oral itraconazole. We took 0.25 ng/mL as a cut-off value for PCT. The study's primary objective was to ascertain the diagnostic performance of PCT in diagnosing CPA. The key secondary outcome was to study the change in the plasma PCT levels after itraconazole therapy.

Results

We included 190 CPA cases and 40 controls (diseased controls [n = 20] and active PTB [n = 20]). PCT was elevated (≥0.25 ng/mL) in only 7 (3.7%) subjects with CPA. The sensitivity and specificity of PCT (≥0.25 ng/mL) were 3.7% (1.5-7.4%) and 100 (91.2-100%), respectively. The area under the curve for plasma PCT was 0.48 (95% confidence interval, 0.39-0.58). The plasma PCT values were available in 93 subjects at six months. There was a significant decline in the median plasma levels of PCT after treatment; however, the PCT levels either increased or remained the same in 45% of the subjects.

Conclusion

Plasma procalcitonin has poor performance in diagnosing and following subjects with CPA.

Current and Future Pathways in Aspergillus Diagnosis

Aspergillus fumigatus has been designated by the World Health Organization as a critical priority fungal pathogen. Some commercially available diagnostics for many forms of aspergillosis rely on fungal metabolites. These encompass intracellular molecules, cell wall components, and extracellular secretomes. This review summarizes the shortcomings of antibody tests compared to tests of fungal products in body fluids and highlights the application of β-d-glucan, galactomannan, and pentraxin 3 in bronchoalveolar lavage fluids. We also discuss the detection of nucleic acids and next-generation sequencing, along with newer studies on Aspergillus metallophores.

Sensitivity of Antigen, Serology, and Microbiology Assays for Diagnosis of the Subtypes of Chronic Pulmonary Aspergillosis at a Teaching Hospital in São Paulo, Brazil

Chronic pulmonary aspergillosis (CPA) is divided into five subtypes. The diagnosis of CPA is complicated due to poor sensitivity of the laboratory tests. Diagnostic performance of different antigen, serological, and microbiological methods in subtypes of CPA is unknown. The purpose of this study was to evaluate the diagnostic performance in different subtypes of CPA. A total of 91 participants with CPA were included, and the study was performed at Hospital das Clínicas of University of São Paulo. Bronchoalveolar lavage galactomannan (73%, 11/15), serology by immunodiffusion test (81%, 61/75), and histology (78%, 39/50) had the best sensitivity. The counterimmunoelectrophoresis (CIE) titers had a significant statistical difference between the CPA subtypes (P < 0.001), in which the forms chronic fibrosing pulmonary aspergillosis (CFPA) and subacute invasive aspergillosis (SAIA) had higher titers: 1/64 (interquartile range [IQR]: 1/32-1/256) and 1/64 (1/32-1/128). C-reactive protein generally presented lower values (median 15 mg/L, IQR: 6-33), with higher values in SAIA and lower values for Aspergillus nodule. Overall, we found a low diagnostic sensitivity of current tests. Regarding the CPA subtypes, we did not find great differences in the performance of the tests, but it is observed that the inflammatory markers and CIE titers tend to be higher in forms of the more extensive lung parenchyma involvement, such as SAIA and CFPA.

Metabolomic profiling of exhaled breath condensate for the diagnosis of pulmonary aspergillosis

Objective

This study aims to ascertain the unique metabolic profile of exhaled breath condensate (EBC) samples in pulmonary aspergillosis (PA) patients, and explore their usefulness for the diagnosis of PA.

Methods

A total of 133 patients were included in the study, including 66 PA patients (invasive pulmonary aspergillosis, n=3; chronic pulmonary aspergillosis, n=60; allergic bronchopulmonary aspergillosis, n=3) and controls (n=67). Ultra high-performance liquid chromatography coupled with high-resolution mass spectrometry(UHPLC-HRMS) was used to analyze EBC samples. Metabolic profiling of EBC samples that were collected from 22 CPA patients at various times during treatment (before treatment, &lt;1 month, 1–2 months, 2–3 months, 3–6 months, and ≥6 months after treatment initiation) were performed using UHPLC-HRMS. Potential biomarkers were evaluated using cluster analysis, Venn diagram and receiver operating characteristic analysis (ROC).

Results

A total of 47 metabolites of potential interest were detected in the EBC samples. Further investigation showed that Asperpyrone C, Kotanin, Terphenyllin, Terrelumamide B, and Cyclotryprostatin D could be used as a diagnostic biomarker for PA. The classification between metabolic profiling of EBC samples from PA patients and controls was good with a sensitivity of 100%, specificity 89.6% for patients with PA, respectively. Venn diagram analysis of these biomarker candidates displayed three main types of compounds, which could be used for the further discrimination of aspergilloma and chronic cavitary PA. In addition, antifungal treatment had a limited influence on the value of the EBC results.

Conclusions

This metabolomic approach using UHPLC-HRMS could be used as a noninvasive method for the diagnosis of PA.

Efficacy of 12-months oral itraconazole versus 6-months oral itraconazole to prevent relapses of chronic pulmonary aspergillosis: an open-label, randomised controlled trial in India

BACKGROUND

Chronic pulmonary aspergillosis has a 5-year mortality of 50-80% globally, and the optimal duration of treatment for chronic pulmonary aspergillosis remains unclear. We aimed to compare the effect of 6-months of oral itraconazole with 12-months of oral itraconazole on chronic pulmonary aspergillosis clinical outcomes.

METHODS

In this single-centre, open-label, randomised controlled trial conducted in one chest clinic in Chandigarh, India, we screened consecutive patients with chronic pulmonary aspergillosis who were naive to antifungal treatment and randomised eligible patients, using block randomisation, to receive a starting dose of 400 mg/day of oral itraconazole for either 6 months or 12 months. There was no masking of participants or investigators. We excluded patients who were unable to provide informed consent; had an intake of any antifungal drugs for more than 3 weeks in the preceding 6 months; had active Mycobacterium tuberculosis or non-tuberculous mycobacterial pulmonary disease; and had allergic, subacute, or invasive forms of aspergillosis. The primary outcome was the proportion of patients having relapse 2 years after treatment initiation. We performed an intention-to-treat analysis for all outcomes. The study is registered with ClinicalTrials.gov, NCT03920527.

FINDINGS

We recruited participants between July 1, 2019, and Aug 31, 2021. We screened 250 patients, of which 164 were included in the trial. 81 patients were randomised to the 6-month group and 83 patients were randomised to the 12-month group. The study population was 78 (48%) women and 86 (52%) men, and the mean age of participants was 44·3 (SD 13·3) years. The proportion of patients experiencing relapse was significantly lower in the 12-month group, 31 (38%) had a relapse in the 6-month group compared with 8 (10%) in the 12-month group, with an absolute risk reduction of 0.29 [95% CI 0·16-0·40]. The mean time to first relapse was 23 months in the 12-month group, which is significantly longer than the mean of 18 months in the 6-month group (p<0.0001). There were 16 deaths in total, eight in each group. Ten (12%) of 81 patients in the 6-months group and 18 (22%) of 83 patients in the 12-months group had adverse effects, with none requiring treatment modification. Nausea and anorexia were the most common adverse events in both groups.

INTERPRETATION

Treatment of chronic pulmonary aspergillosis with 12 months of oral itraconazole was superior to 6 months of oral itraconazole in reducing relapses at 2 years. Itraconazole should be given for at least 12 months for treating chronic pulmonary aspergillosis.

FUNDING

None.

TRANSLATION

For the Hindi translation of the abstract see Supplementary Materials section.

Efficacy of LD Bio Aspergillus ICT Lateral Flow Assay for Serodiagnosis of Chronic Pulmonary Aspergillosis

Background: The diagnosis of CPA relies on the detection of the IgG Aspergillus antibody, which is not freely available, especially in resource-poor settings. Point-of-care tests like LDBio Aspergillus ICT lateral flow assay, evaluated in only a few studies, have shown promising results for the diagnosis of CPA. However, no study has compared the diagnostic performances of LDBio LFA in setting of tuberculosis endemic countries and have compared it with that of IgG Aspergillus. Objectives: This study aimed to evaluate the diagnostic performances of LDBio LFA in CPA and compare it with existing the diagnostic algorithm utilising ImmunoCAP IgG Aspergillus. Methods: Serial patients presenting with respiratory symptoms (cough, haemoptysis, fever, etc.) for >4 weeks were screened for eligibility. Relevant investigations, including direct microscopy and culture of respiratory secretions, IgG Aspergillus, chest imaging, etc., were done according to existing algorithm. Serums of all patients were tested by LDBio LFA and IgG Aspergillus (ImmunoCAP Asp IgG) and their diagnostic performances were compared. Results: A total of 174 patients were included in the study with ~66.7% patients having past history of tuberculosis. A diagnosis of CPA was made in 74 (42.5%) of patients. The estimated sensitivity and specificity of LDBio LFA was 67.6% (95% CI: 55.7−78%) and 81% (95% CI: 71.9−88.2%), respectively, which increased to 73.3% (95% CI: 60.3−83.9%) and 83.9% (95% CI: 71.7−92.4%), respectively, in patients with a past history of tuberculosis. The sensitivity and specificity of IgG Aspergillus was 82.4% (95% CI: 71.8−90.3%) and 82% (95% CI: 73.1−89%); 86.7% (95% CI: 75.4−94.1%) and 80.4% (95% CI: 67.6−89.8%), in the whole group and those with past history of tuberculosis, respectively. Conclusions: LDBio LFA is a point-of-care test with reasonable sensitivity and specificity. However, further tests may have to be done to rule-in or rule-out the diagnosis of CPA in the appropriate setting.

Respiratory MUC5B disproportion is involved in severe community-acquired pneumonia

BACKGROUND

Mucus production is a process involved in the pathogenesis of Community-acquired pneumonia (CAP). The study is to determine Mucin 5B (MUC5B) protein concentration and its proportion in the bronchoalveolar lavage fluid (BALF) of CAP patients and evaluate its value to help assess disease severity.

METHODS

A total of 118 patients were enrolled in this cross-sectional study, including 45 with severe CAP (SCAP) and 73 with non-severe CAP (NSCAP). MUC5B concentration in BALF were determined by immunoblotting analysis. Total protein concentration of BALF was detected by Pierce BCA kit. Cytokines IL6, IL10, IFNγ, IL13, and IL17 in BALF were measured using commercial enzyme-linked immunosorbent assay (ELISA). Spearman's correlation analysis was applied to evaluate the relationships between MUC5B concentration or MUC5B/total protein ratio and the CURB-65 score, as well as cytokines. Logistic regression analysis was used to identify the independent factors associated with severe CAP. Receiver operating characteristic (ROC) curve was used to evaluate the assessment value of MUC5B/total protein ratio and other indexes for CAP severity.

RESULTS

MUC5B concentration in the BALF of NSCAP group was higher than that in SCAP group [NSCAP 13.56 µg/ml (IQR 5.92-25.79) vs. SCAP 8.20 µg/ml (IQR 4.97-14.03), p = 0.011]. The total protein concentration in the BALF of NSCAP group was lower than that in SCAP group [NSCAP 0.38 mg/ml (IQR 0.15-1.10) vs. SCAP 0.68 mg/ml (IQR 0.46-1.69), p = 0.002]. The MUC5B/total protein ratio was remarkably higher in NSCAP group than that in SCAP groups [NSCAP 3.66% (IQR 1.50-5.56%) vs. SCAP 1.38% (IQR 0.73-1.76%), p < 0.001]. MUC5B/total protein ratio was negatively correlated with total protein concentration (r_s = - 0.576, p < 0.001), IL6 (r_s = - 0.312, p = 0.001), IL10 (r_s = - 0.228, p = 0.013), IL13 (r_s = - 0.183, p = 0.048), IL17 (r_s = - 0.282, p = 0.002) and CURB-65 score (r_s = - 0.239, p = 0.009). Logistic regression identified that MUC5B/total protein ratio, IL6 level and CURB-65 score as independent variables related to CAP severity. ROC curve demonstrated best assessment value of MUC5B/total protein ratio for SCAP (AUC 0.803, p < 0.001), with a sensitivity of 88.9% and a specificity of 64.4%.

CONCLUSIONS

Respiratory MUC5B disproportion is related to CAP severity. MUC5B/total protein ratio may serve as an assessment marker and a potential therapeutic target for severe CAP.

Clinical Features, Diagnostic Test Performance, and Prognosis in Different Subtypes of Chronic Pulmonary Aspergillosis

Objective

The aim of this study was to describe clinical features in different subtypes of chronic pulmonary aspergillosis (CPA)-simple aspergilloma (SA), chronic cavitary pulmonary aspergillosis (CCPA), chronic fibrosing pulmonary aspergillosis (CFPA), aspergillus nodule (AN), and subacute invasive aspergillosis (SAIA), respectively, and identify long-term prognosis of CPA.

Methods

We reviewed patients diagnosed with different subtypes of CPA from 2002 to 2020 at Nanjing Jinling Hospital, China. We analyzed the clinical and survival information of five different subgroups. A Cox regression model was used to explore proper antifungal duration and long-term survival factors of CCPA and SAIA.

Results

A total of 147 patients with CPA were included, consisting of 11 SA, 48 CCPA, 5 CFPA, 12 AN, and 71 SAIA. The most common underlying pulmonary disease was pulmonary tuberculosis (n = 49, 33%), followed by bronchiectasis (n = 46, 31.3%) and chronic obstructive pulmonary disease (COPD) or emphysema (n = 45, 30.6%), while in SAIA and CFPA groups, the most common was COPD or emphysema (45.1 and 100%). Cough (85%), expectoration (70.7%), hemoptysis (54.4%), and fever (29.9%) were common symptoms, especially in CCPA, CFPA, and SAIA groups. The common imaging manifestations included cavitation (n = 94, 63.9%), fungal ball (n = 54, 36.7%), pleural thickening (n = 47, 32.0%), and bronchiectasis (n = 46, 31.3%). SAIA and CFPA groups had a lower value of hemoglobin (HB) and serum albumin (ALB) with higher C-reactive protein and erythrocyte sedimentation rate. The positive rate of sputum culture, serum galactomannan (GM), and bronchoalveolar lavage fluid GM was 32.7% (36/110), 18.4% (18/98), and 48.7% (19/39), respectively. There were 64.6% (31/48) patients with CCPA and 25.4% (18/71) patients with SAIA who received surgery and the 5-year cumulative survival rate was 92.1 and 66.6%, respectively. SAIA, old age, male, low body mass index (BMI), COPD or emphysema, multiple distribution, low serum ALB, and positive sputum culture were adverse prognosis factors for SAIA and CCPA group, and BMI ≤ 20.0 kg/m² was independently associated with increased mortality (hazard ratio (HR) 5.311, 95% CI 1.405–20.068, p = 0.014). Multivariable Cox regression indicated that surgery (HR 0.093, 95% CI 0.011–0.814, p = 0.032) and antifungal duration >6 months (HR 0.204, 95% CI 0.060–0.696 p = 0.011) were related to improved survival.

Conclusion

The clinical features and laboratory test performance are different among SA, CCPA, CFPA, AN, and SAIA. Low BMI was an independent risk factor for survival. Selective surgery and antifungal duration over 6 months were associated with improved survival.

Role of flexible bronchoscopy in the diagnosis of invasive fungal infections

BACKGROUND

There are sparse data on the role of flexible bronchoscopy (FB) in diagnosing invasive mould infections (IMIs).

OBJECTIVE

To investigate the safety and usefulness of FB in IMI. We evaluate the factors associated with a successful diagnosis of IMI using FB. Further, we compare subjects of invasive pulmonary aspergillosis (IPA) with pulmonary mucormycosis (PM).

METHODS

We retrospectively reviewed the clinical features, imaging data, bronchoscopy, microbiology and pathology details of subjects who underwent FB for suspected IMI. We categorised FB as diagnostic if it contributed to the diagnosis of IMI. We performed a multivariate analysis to identify the factors associated with a diagnostic bronchoscopy.

RESULTS

Of the 3521 FB performed over 18 months, 132 (3.7%) were done for suspected IMIs. We included 107 subjects for the final analysis. The risk factors for IMI included renal transplantation (29.0%), diabetes (27.1%), haematological malignancy (10.3%) and others. We found bronchoscopic abnormalities in 33 (30.8%) subjects, and these were more frequent in those with confirmed PM (67%) than IPA (27%). IMI was confirmed in 79 (14 proven, 48 probable and 17 possible) subjects. FB was diagnostic in 71%. We experienced major complications in three cases (2.7%), including one death. On multivariate analysis, the visualisation of endobronchial abnormalities during FB (OR [95%, CI], 8.5 [1.4-50.4]) was the only factor associated with a diagnostic FB after adjusting for age and various risk factors.

CONCLUSIONS

Flexible bronchoscopy is a useful and safe procedure in diagnosing IMIs. The presence of endobronchial abnormalities predicts a successful diagnostic yield on FB.

Prevalence of Vitamin D Deficiency in Treatment-Naïve Subjects with Chronic Pulmonary Aspergillosis

The association of vitamin D deficiency in the pathogenesis of invasive and allergic pulmonary aspergillosis is known. Whether vitamin D deficiency is prevalent in chronic pulmonary aspergillosis (CPA) remains unknown. We evaluated the prevalence of vitamin D deficiency in subjects with CPA. We compared the clinicoradiological features, microbiology, the immunological response, and the severity of CPA in those with or without vitamin D deficiency. We measured plasma vitamin D levels in 230 consecutive treatment-naïve subjects with CPA and 78 controls (28 with prior tuberculosis (TB); 50 healthy controls). We defined vitamin D deficiency as 25(OH)D3 level <20 ng/mL. The mean (95% confidence intervals (CI)) levels of plasma vitamin D levels were 19.5 (17.6–21.4), 18.6 (13.9–23.3), and 15.3 (12.6–17.9) ng/mL in subjects with CPA, diseased controls, and healthy controls, respectively; and the levels were not different between the groups. The prevalence of vitamin D deficiency in subjects with CPA was 65% (n = 150) and was also not different between healthy (70%) or diseased (61%) controls. We did not find any difference in the clinicoradiological features, microbiology, immunological response, and severity of CPA between vitamin D sufficient and deficient groups. The prevalence of vitamin D deficiency is high in subjects with CPA, albeit similar to controls. Vitamin D deficiency does not affect the disease severity in subjects with CPA.

Chronic Pulmonary Aspergillosis: Notes for a Clinician in a Resource-Limited Setting Where There Is No Mycologist

Chronic pulmonary aspergillosis (CPA) is a spectrum of several progressive disease manifestations caused by Aspergillus species in patients with underlying structural lung diseases. Duration of symptoms longer than three months distinguishes CPA from acute and subacute invasive pulmonary aspergillosis. CPA affects over 3 million individuals worldwide. Its diagnostic approach requires a thorough Clinical, Radiological, Immunological and Mycological (CRIM) assessment. The diagnosis of CPA requires (1) demonstration of one or more cavities with or without a fungal ball present or nodules on chest imaging, (2) direct evidence of Aspergillus infection or an immunological response to Aspergillus species and (3) exclusion of alternative diagnoses, although CPA and mycobacterial disease can be synchronous. Aspergillus antibody is elevated in over 90% of patients and is the cornerstone for CPA diagnosis. Long-term oral antifungal therapy improves quality of life, arrests haemoptysis and prevents disease progression. Itraconazole and voriconazole are alternative first-line agents; voriconazole is preferred for patients with contra-indications to itraconazole and in those with severe disease (including large aspergilloma). In patients co-infected with tuberculosis (TB), it is not possible to treat TB with rifampicin and concurrently administer azoles, because of profound drug interactions. In those with pan-azole resistance or intolerance or progressive disease while on oral triazoles, short-term courses of intravenous liposomal amphotericin B or micafungin is used. Surgery benefits patients with well-circumscribed simple aspergillomas and should be offered earlier in low-resource settings.

An overview of the available treatments for chronic cavitary pulmonary aspergillosis

INTRODUCTION

Chronic pulmonary aspergillosis (CPA) is a chronic lung infection caused by Aspergillus fumigatus, that complicates structural lung diseases. Of the different types of CPA, chronic cavitary pulmonary aspergillosis (CCPA) is the most common form. The mainstay of treatment of CCPA is oral triazoles. However, many gaps exist in clinical decision-making about the agent of choice, the duration, and the assessment of treatment response.

AREAS COVERED

We discuss the approach to diagnosis and treatment of CCPA. We have searched the PubMed and EmBase databases (from inception till 31 October 2019) to identify studies describing the use of anti-fungal agents in CCPA.

EXPERT OPINION

Treatment for CCPA should be initiated with oral itraconazole for at least six months. In case of poor response or intolerance to itraconazole, voriconazole should be considered. Intravenous agents, including amphotericin B and echinocandins, may be used in those with either treatment failure or those who are intolerant to oral antifungal agents. Posaconazole and isavuconazole may be used as salvage therapy due to a better pharmacokinetic/pharmacodynamic profile of the former and reduced drug-drug interactions with the latter.

Potential value of serum Aspergillus IgG antibody detection in the diagnosis of invasive and chronic pulmonary aspergillosis in non-agranulocytic patients

BACKGROUND

At present, serum Aspergillus IgG and IgM antibody detection is mainly used in the diagnosis of chronic pulmonary aspergillosis (CPA), but its value in the diagnosis of invasive pulmonary aspergillosis (IPA) in non-agranulocytic patients is still unclear. IgM can be used as a marker of acute infection to help diagnose acute infection-related diseases. IgG is a marker of long-term infection and is used to assist in the diagnosis of pre-existing or chronic infection-related diseases. The aim of this study was to investigate and compare the value of serum Aspergillus IgG and IgM antibody detection in the diagnosis of IPA and CPA in non-agranulocytic patients.

METHODS

Fifty-eight cases of pulmonary aspergillosis (37 IPA and 21 CPA cases), 15 cases of community-acquired bacterial pneumonia and 50 cases in the healthy control group were collected. The serum (1,3)-β-D-glucan test (G test) was performed with a chromogenic method, and the galactomannan test (GM test) and Aspergillus IgG and IgM antibody detection were performed by commercial enzyme-linked immunosorbent assay (ELISA) in all patients. The sensitivity and specificity, cut-off value and area under the curve (AUC) of Aspergillus IgG and IgM antibodies were further obtained by receiver operating characteristic (ROC) curves.

RESULTS

The positive rate of the G test, Aspergillus IgG antibody detection and the GM test also showed notable differences among the IPA, CPA, community-acquired bacterial pneumonia and healthy groups (P = 0.006, P <  0.001 and P = 0.217, respectively). Only the positive rate of the GM test showed a significant difference between the IPA and CPA groups (P = 0.04). ROC curves indicated that Aspergillus IgG antibody detection had a higher specificity in the IPA group than in the CPA group (0.952). The detection of Aspergillus IgG antibody can preferably distinguish IPA from community-acquired bacterial pneumonia and healthy controls (sensitivity = 0.923, specificity = 0.459, cut-off value = 134.46, AUC = 0.727). It can also distinguish CPA from community-acquired bacterial pneumonia and healthy controls (sensitivity = 0.952, specificity = 0.692, cut-off value = 75.46, AUC = 0.873).

CONCLUSIONS

Serum Aspergillus IgG antibody detection may have certain clinical value in the diagnosis of IPA and CPA in non-agranulocytic patients.

Post tuberculosis treatment infectious complications

Following greater attention and follow-up of patients with treated pulmonary tuberculosis (TB), it has emerged that infections are more likely to occur in this cohort of patients. This comes as no surprise, as pulmonary TB is a destructive process that leads to cicatrization, alteration of parenchyma, bronchiectasis, and scarring of the lung, with reduction of lung volumes and an impact on pulmonary function. In addition to relapse and re-infection with TB, other pathogens are increasingly recognized in post-TB patients. This paper serves as a summary and guide on how to approach the post-TB patient with new signs and symptoms of pulmonary infection in order to ensure optimal management and rehabilitation.

Efficiency of A fumigatus-specific IgG and galactomannan testing in the diagnosis of simple aspergilloma

BACKGROUND

An early diagnosis of chronic pulmonary aspergillosis (CPA) at the stage of simple aspergilloma (SA) remains a challenge in low- and middle-income countries, where imaging may not be routinely available.

OBJECTIVE

We investigate the role of Aspergillus fumigatus-specific IgG in serum, and galactomannan (GM) in bronchoalveolar lavage fluid (BALF) and serum for the diagnosis of SA.

METHODS

We included 46 consecutive treatment-naïve subjects with SA. The 81 controls were subjects of treated pulmonary tuberculosis with residual radiological abnormality and minimal symptoms; and subjects with pulmonary disorders other than CPA who underwent bronchoscopy. The diagnosis of SA was based on consistent clinical features along with radiological manifestations (cavity with fungal ball).

RESULTS

Using receiver operating characteristic (ROC) curve analysis, the best cut-off value for A fumigatus-specific IgG was 27.3 mgA/L (AUROC, 0.839; sensitivity, 63.5%; specificity, 98.3%). The best cut-off value for serum and BALF-GM was 0.7 (AUROC, 0.636; sensitivity, 32%; specificity, 96.2%) and 2.5 (AUROC, 0.833; sensitivity, 63.7%; specificity, 97.1%), respectively. A combination of A fumigatus-specific IgG (>27 mgA/L) or serum GM (≥0.7) or BALF-GM (≥2.5) had a sensitivity and specificity of 82.6% and 96%, respectively.

CONCLUSIONS

A combination of serological tests has the best sensitivity in diagnosing SA. More studies are needed to confirm our findings.

Monitoring treatment response in chronic pulmonary aspergillosis: role of clinical, spirometric and immunological markers

OBJECTIVES

The treatment response in chronic pulmonary aspergillosis (CPA) is usually assessed based on the improvement in clinical and imaging findings. Herein, we evaluate serum Aspergillus fumigatus-specific IgG, serum galactomannan, weight change, and lung function for assessing treatment response in subjects with CPA.

METHODS

We categorized treatment response as favourable (improved or stable clinical response with radiologically improved or stable disease) or unfavourable (worsening of symptoms or radiological progression) after 6 months of treatment with antifungal azoles. We measured A. fumigatus-specific IgG, serum galactomannan, weight, and lung function at baseline, 3 months, and 6 months in those with favourable and unfavourable treatment response.

RESULTS

One hundred and twenty-six consecutive treatment-naïve subjects (53.2% (67/126) males; mean ± SD age, 42.3 ± 14.7 years) with CPA were included. One hundred and six and 20 were classified as having favourable and unfavourable response, respectively. After 6 months of treatment, the decline in serum A. fumigatus-specific IgG (n = 119) was similar in those with favourable or unfavourable response (mean ± SD, -26.3 ± 45.5 mgA/L vs. -3.4 ± 65.6 mgA/L; p 0.20). There was no significant change in the serum galactomannan (favourable vs. unfavourable: mean ± SD, -0.11 ± 2.8 vs. -0.62 ± 2; p 0.92) or FEV1 (favourable vs. unfavourable: mean ± SD, 24 ± 250 mL vs. -62 ± 154 mL; p 0.19) after 6 months of treatment. There was significant loss of weight (mean ± SD, -2.5 ± 4.5 kg) in subjects with unfavourable response.

CONCLUSION

Serum A. fumigatus-specific IgG and serum galactomannan inconsistently decrease following treatment and may not be useful indicators for monitoring treatment response in CPA. Similarly, there is little change in pulmonary function following treatment. A gain in body weight is seen in those with favourable response.