Prevalence and predictors of Aspergillus seropositivity and chronic pulmonary aspergillosis in an urban tertiary hospital in Sierra Leone: A cross-sectional study

Prevalence of Chronic Pulmonary Aspergillosis in Patients With Mycobacterial and Non-Mycobacterial Tuberculosis Infection of the Lung: A Systematic Review and Meta-Analysis

BACKGROUND

Post-mycobacterial residual lung abnormality (PMLA) from prior tuberculous (PTLA) or non-tuberculous mycobacterial (PNTLA) lung infections predisposes to chronic pulmonary aspergillosis (CPA). However, the prevalence of CPA in patients with PMLA remains uncertain. We aimed to determine the prevalence of CPA in patients with PMLA.

METHODS

We performed a systematic search of PubMed and Embase databases up to January 31, 2025, to identify studies reporting CPA prevalence in patients with PTLA or PNTLA (excluding those with active tuberculosis). The pooled prevalence was calculated using frequentist meta-analysis (primary outcome), with Bayesian and trim-and-fill methods as sensitivity analyses. Study heterogeneity (I2) and publication bias were assessed. We performed multivariable meta-regression to evaluate factors affecting heterogeneity.

RESULTS

Thirty-one studies (4172 PTLA and 13,905 PNTLA) were included. Frequentist meta-analysis yielded a pooled CPA prevalence of 18% (95% confidence interval [CI], 11.6-25.4). Bayesian analysis with informative priors estimated prevalence of 7.1% (95% Credible Index, 4.5-10.4), and trim-and-fill adjustment for publication bias suggested prevalence to be 3.4% (95% CI, 0.69-7.7). On a multivariable analysis, we found CPA prevalence higher in hospital-based studies, high TB burden settings and studies with prospective or cross-sectional study designs; although CPA prevalence was higher in PTLA (23.1%) than in PNTLA (7%), it was not significantly different. We detected substantial heterogeneity (I2 = 98.8%) and publication bias.

CONCLUSION

There is a high prevalence of CPA in patients with PMLA, particularly in TB-endemic regions and hospital settings. Patients with PMLA should be routinely screened for CPA in high prevalence settings.

Chronic pulmonary aspergillosis in tea population of Assam

BACKGROUND

Chronic pulmonary aspergillosis (CPA) is a disease commonly caused by Aspergillus fumigatus and other Aspergillus species characterized by cavitary lung lesions. Tea garden population is an agrarian population of Assam, mostly associated with tea plantations. Assam is a major tea-producing state with 803 tea gardens producing approximately 50% of the total tea in India, of which 177 are present in the Dibrugarh district alone. Tuberculosis is common in tea garden workers. This community-based cross-sectional study in the tea garden community of Dibrugarh was done to find the prevalence of Aspergillus IgG antibodies and CPA cases in individuals with chronic respiratory symptoms.

METHODOLOGY AND PRINCIPAL FINDINGS

Patients visiting 3 tea garden hospitals and 2 referral hospitals with chronic cough and/or haemoptysis, weight loss/fatigue, and other respiratory symptoms for a duration of 3 months or more were included in this one-year study. Serum samples were tested by Immunocap Phadia 200 for Aspergillus fumigatus-specific IgG antibodies. CPA cases were diagnosed based on clinical, radiological, and serological criteria. Out of 128 samples, seropositivity was seen in 41 (32.0%) patients (cutoff value: 27 mgA/l). Male preponderance (1.6:1) with a mean age of 41.9 (±15.69) was observed. Haemoptysis and fatigue were significant symptoms seen (p-values: 0.0086 and 0.0098, respectively). Aspergillus fumigatus-specific IgG antibody was found to be significantly high in 29 out of 76 patients (38.1%) with a history of tuberculosis. Amongst them, seropositivity with active TB was 5 out of 27 patients (18.5%), and seropositivity with post-TB was 24 out of 49 patients (48.9%). Chronic cavitary pulmonary aspergillosis was the predominant type (38.1%). Proven CPA (clinically, radiologically, and serologically positive) were 22 (17.1%, 95% CI 10.7%-26.0%), and possible CPA (clinically and serologically positive but without radiological data) were 19 (14.8%, 95% CI 8.9%-23.1%).

CONCLUSION

A high prevalence of CPA (60 per 100 000) was detected. High Aspergillus seropositivity of 48.9% was seen in the post-TB population. Aspergillus-specific IgG antibody testing is the only confirmatory method for diagnosing CPA, which is available in limited centres in India. Aspergillus seropositivity should be detected in post-TB patients presenting with chronic respiratory symptoms.

Chronic Pulmonary Aspergillosis as a Considerable Complication in Post-Tuberculosis Lung Disease

Post-tuberculosis lung disease (PTLD) has only recently been put in the spotlight as a medical entity. Recent data suggest that up to 50% of tuberculosis (TB) patients are left with PTLD-related impairment after completion of TB treatment. The presence of residual cavities in the lung is the largest risk factor for the development of chronic pulmonary aspergillosis (CPA) globally. Diagnosis of CPA is based on four criteria including a typical radiological pattern, evidence of Aspergillus species, exclusion of alternative diagnosis, and a chronic course of disease. In this manuscript, we provide a narrative review on CPA as a serious complication for patients with PTLD.

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.

Prevalence of chronic pulmonary aspergillosis along the continuum of pulmonary tuberculosis care: A protocol for a living systematic review and meta-analysis

INTRODUCTION

Chronic pulmonary aspergillosis (CPA) is a debilitating disease estimated to affect over 3 million people worldwide. Pulmonary tuberculosis (PTB) is the most significant risk factor for CPA. However, the true burden of CPA at the time of PTB diagnosis, during, and after PTB treatment remains unknown. In this paper, we present a protocol for a living systematic review aimed at estimating the current burden of CPA along the continuum of PTB care.

MATERIALS AND METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines to formulate this protocol, which is registered with the International Prospective Register of Systematic Reviews (PROSPERO: CRD42023453900). We will identify primary literature through various electronic databases, including CINAHL, Ovid MEDLINE, MEDLINE (PubMed), EMBASE, Google Scholar, Cochrane Database of Systematic Reviews, and African Journal Online. The search will encompass articles from inception to December 31st, 2023, using medical subject heading search terms "pulmonary tuberculosis" AND "chronic pulmonary aspergillosis". Two reviewers will independently assess titles, abstracts, and full texts for eligibility using the Covidence web-based software. The eligible studies will comprise original observational research that reports on the prevalence of CPA diagnosed in individuals with PTB, based on established criteria, without language or geographic restriction. We intend to exclude single case reports and case series with fewer than 10 participants, as well as review articles, guidelines, and letters to the editors. Cochrane Risk of Bias Tools (ROB2 and ROBINS-I) will used to assess study quality and risk of bias and the quality of the evidence will be rated using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool. Our data syntheses will encompass meta-analysis and meta-regression, conducted using STATA version 18 and R- Studio version 4.0.2. This systematic review will be updated every 3-5 years as more data emerges.

CONCLUSIONS

The findings of this proposed systematic review will summarize the available evidence on the occurrence of CPA, at the time of PTB diagnosis, during and after PTB treatment. The study results have the potential to guide healthcare policies regarding screening for CPA, enhance clinical decision-making, and catalyse further research into understanding the interplay between PTB and CPA. By shedding light on the current burden of CPA along the continuum of PTB care, we aspire to contribute to the betterment of patient care, disease management, and global health outcomes.

PROSPERO REGISTRATION

CRD42023453900.

Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis compared to the reference standard

OBJECTIVES

To evaluate the performance of Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis (CPA) by using a cohort of patients with histologically proven CPA as a reference standard.

METHODS

We collected Aspergillus-specific IgG antibody titres from patients with histologically proven CPA in collaboration with CPAnet study sites in Denmark, Germany, Belgium, India, Moldova, and Pakistan (N = 47). Additionally, sera from diseased and healthy controls were prospectively collected at the Medical Clinic of the Research Center, Borstel, Germany (n = 303). Aspergillus-specific IgG antibody titres were measured by the ImmunoCAP® assay (Phadia 100, Thermo Fisher Scientific, Uppsala, Sweden). An Aspergillus-specific IgG antibody titre ≥50 mgA/L was considered positive.

RESULTS

Using patients with histologically proven CPA as the reference standard, the ImmunoCAP® Aspergillus-specific IgG antibody test had a sensitivity and specificity of 85.1% (95% CI: 71.7-93.8%) and 83.6% (95% CI: 78.0-88.3%), respectively. Patients with histologically proven CPA had significantly higher Aspergillus-specific IgG antibody titre with a median of 83.45 mgA/L (interquartile range 38.9-115.5) than all other cohorts (p < 0.001). False-positive test results occurred in one-third of 79 healthy controls.

DISCUSSION

Our study results confirm a high sensitivity of the Aspergillus-specific IgG antibody test for the diagnosis of CPA when using patients with histologically proven CPA as a reference standard. However, positive test results should always match radiological findings as false-positive test results limit the interpretation of the test.