Risk factors for relapse of chronic pulmonary aspergillosis after discontinuation of antifungal therapy

Characterization of Aspergillus fumigatus secretome during sublethal infection of Galleria mellonella larvae

Introduction. The fungal pathogen Aspergillus fumigatus can induce prolonged colonization of the lungs of susceptible patients, resulting in conditions such as allergic bronchopulmonary aspergillosis and chronic pulmonary aspergillosis.Hypothesis. Analysis of the A. fumigatus secretome released during sub-lethal infection of G. mellonella larvae may give an insight into products released during prolonged human colonisation.Methodology. Galleria mellonella larvae were infected with A. fumigatus, and the metabolism of host carbohydrate and proteins and production of fungal virulence factors were analysed. Label-free qualitative proteomic analysis was performed to identify fungal proteins in larvae at 96 hours post-infection and also to identify changes in the Galleria proteome as a result of infection.Results. Infected larvae demonstrated increasing concentrations of gliotoxin and siderophore and displayed reduced amounts of haemolymph carbohydrate and protein. Fungal proteins (399) were detected by qualitative proteomic analysis in cell-free haemolymph at 96 hours and could be categorized into seven groups, including virulence (n = 25), stress response (n = 34), DNA repair and replication (n = 39), translation (n = 22), metabolism (n = 42), released intracellular (n = 28) and cellular development and cell cycle (n = 53). Analysis of the Gallerial proteome at 96 hours post-infection revealed changes in the abundance of proteins associated with immune function, metabolism, cellular structure, insect development, transcription/translation and detoxification.Conclusion. Characterizing the impact of the fungal secretome on the host may provide an insight into how A. fumigatus damages tissue and suppresses the immune response during long-term pulmonary colonization.

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.

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.

The Development and Validation of a Predictive Model for Voriconazole-Related Liver Injury in Hospitalized Patients in China

Voriconazole is widely used in the treatment and prevention of invasive fungal diseases. Common drug-induced liver injuries increase the economic burdens and the risks of premature drug withdrawal and disease recurrence. This study estimated the disposal cost of voriconazole-related liver injury, explored the risk factors of voriconazole-related liver injury in hospitalized patients, and established a predictive model of liver injury to assist clinicians and pharmacists in estimating the probability or risk of liver injury after voriconazole administration to allow for early identification and intervention in patients at high risk of liver injury. A retrospective study was conducted on the selected inpatients whose blood concentration of voriconazole was measured in the West China Hospital of Sichuan University from September 2016 to June 2020. The incidence and disposal cost of voriconazole-related liver injuries were calculated. The incidence of voriconazole-related liver injury was 15.82% (217/1372). The disposal cost has been converted to 2023 at a discount rate of 5%. The median (P₂₅, P₇₅) disposal cost of severe liver injury (n = 42), general liver injury (n = 175), and non-liver injury (n = 1155) was 993.59 (361.70, 1451.76) Chinese yuan, 0.00 (0.00, 410.48) yuan, and 0.00 (0.00, 0.00) yuan, respectively, with a statistically significant difference (p < 0.001). Single factor analysis and multiple factor logistic regression were used to analyze the risk factors of voriconazole-related liver injury. The voriconazole-related liver injury was related to the trough concentration (C_min, OR 1.099, 95% CI 1.058-1.140), hypoproteinemia (OR 1.723, 95% CI 1.126-2.636), and transplantation status (OR 0.555, 95% CI 0.325-0.948). The prediction model of liver injury was Logit (P)= -2.219 + 0.094 × C_min + 0.544 × H_{ydroproteinemia} - 0.589 × Transplantation, and the prediction model nomogram was established. The model validation results showed that the C-index of the derivation set and validation set was 0.706 and 0.733, respectively. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve was 0.705 and 0.733, respectively, indicating that the model had good prediction ability. The prediction model will be helpful to develop clinical individualized medication of voriconazole and to identify and intervene in the cases of patients at high risk of voriconazole-related liver injury early on, in order to reduce the incidence of voriconazole-related liver injuries and the cost of treatment.

Nanotechnology-Based Approaches for Voriconazole Delivery Applied to Invasive Fungal Infections

Invasive fungal infections increase mortality and morbidity rates worldwide. The treatment of these infections is still limited due to the low bioavailability and toxicity, requiring therapeutic monitoring, especially in the most severe cases. Voriconazole is an azole widely used to treat invasive aspergillosis, other hyaline molds, many dematiaceous molds, Candida spp., including those resistant to fluconazole, and for infections caused by endemic mycoses, in addition to those that occur in the central nervous system. However, despite its broad activity, using voriconazole has limitations related to its non-linear pharmacokinetics, leading to supratherapeutic doses and increased toxicity according to individual polymorphisms during its metabolism. In this sense, nanotechnology-based drug delivery systems have successfully improved the physicochemical and biological aspects of different classes of drugs, including antifungals. In this review, we highlighted recent work that has applied nanotechnology to deliver voriconazole. These systems allowed increased permeation and deposition of voriconazole in target tissues from a controlled and sustained release in different routes of administration such as ocular, pulmonary, oral, topical, and parenteral. Thus, nanotechnology application aiming to delivery voriconazole becomes a more effective and safer therapeutic alternative in the treatment of fungal infections.

Imaging Spectrum in Chronic Pulmonary Aspergillosis

Chronic pulmonary aspergillosis (CPA) is a life-threatening respiratory fungal infection that is almost exclusively seen in patients with preexisting structural lung disease with no or mild immunosuppression. The clinical presentation and imaging findings are varied and often pose a diagnostic challenge; and the disease is often present for a long time before being correctly diagnosed. High-resolution chest computed tomography is the imaging modality of choice because it helps identify various forms of CPA, which can range from a simple aspergilloma and chronic cavitary form, to the subacute invasive and end-stage fibrotic form. The knowledge of the imaging features of this disease cannot be overemphasized because it can assist the clinician in reaching at an early diagnosis and timely initiation of appropriate antifungal therapy, thereby improving patient management and treatment outcome. Moreover, imaging also plays a pivotal role during follow-up in patients of CPA to assess the treatment response. In the current review, we present an illustrative review of radiologic patterns seen in various forms of CPA.

Differences in the clinical characteristics of chronic pulmonary aspergillosis according to spirometric impairment

The clinical features by declining lung function remain uncharacterized in chronic pulmonary aspergillosis (CPA) patients. We investigated the clinical characteristics of CPA patients based on spirometric impairments (restrictive spirometric pattern [RSP] and obstructive spirometric pattern [OSP]) and their severity. We retrospectively analyzed medical records of CPA patients who underwent pulmonary function tests from March 2017 to February 2020. We used Global Lung Initiative 2012 equations with lower limit of normal. The clinical characteristics of patients with RSP were compared to those with OSP. Additionally, RSP patients’ characteristics were analyzed according to forced vital capacity (FVC) tertile, and OSP patients’ characteristics were analyzed according to forced expiratory volume in 1 second (FEV₁) tertile. Among the 112 patients with CPA (52 [46%] with RSP and 60 [54%] with OSP), body mass index (BMI) was significantly lower in patients with RSP than in those with OSP (17.6 kg/m² versus 20.3 kg/m²; P = 0.003), and non-tuberculous mycobacterial disease was more frequently observed in patients with RSP than in those with OSP (28.8% versus 11.7%; P = 0.004). Additionally, for patients with RSP, younger age and bilateral pulmonary lesions were more frequently observed in the first tertile group than in the other groups (P for trend: 0.025 and 0.001, respectively). For patients with OSP, low BMI, paracavitary infiltrates, and elevated WBC count were more frequently observed in the first tertile group than in the other groups (P for trend: < 0.001, 0.011, and 0.041, respectively). Differences in the clinical features of CPA patients were identified according to heterogeneous spirometric patterns and their severity. Further studies are needed to investigate the clinical significance of these findings.

Performance of LDBio Aspergillus WB and ICT Antibody Detection in Chronic Pulmonary Aspergillosis

The detection of Aspergillus antibody has a key role in the diagnosis of chronic pulmonary aspergillosis. Western blot (WB) and immunochromatography (ICT) lateral flow detection of Aspergillus antibody can be used as confirmatory and screening assays but their comparative performance in TB patients is not known. This study investigated the performance of these assays among 88 post-tuberculosis patients with suspected CPA. Sensitivity, specificity, receiver operating curve (ROC), area under-curve (AUC) and the agreement between two assays were evaluated. Both WB and ICT showed good sensitivity (80% and 85%, respectively) for detection of Aspergillus antibodies. Substantial agreement (0.716) between these assays was also obtained. The highest AUC result (0.804) was achieved with the combination of WB and ICT. The global intensity of WB correlated with the severity of symptoms in CPA group (p = 0.001). The combination of WB and ICT may increase specificity in CPA diagnosis.

Tolerability of oral itraconazole and voriconazole for the treatment of chronic pulmonary aspergillosis: A systematic review and meta-analysis

BACKGROUND

Chronic pulmonary aspergillosis (CPA) requires prolonged treatment with itraconazole or voriconazole. However, adverse events (AEs) are common with the use of these agents, with the need to discontinue the offending drug in a significant proportion of the patients. The aim of this study was to evaluate the frequency of adverse events of itraconazole and voriconazole for the treatment of CPA.

METHODS

We searched Embase and Medline to select clinical studies providing information on AEs to itraconazole or voriconazole for the treatment of CPA from inception to May 2020. Reviews, single case reports, and case series reporting less than 10 patients were excluded. Random effect meta-analysis was performed using STATA 16.0.

RESULTS

We included 9 eligible studies with an overall total of 534 CPA patients enrolled. Of these, 69% (n = 366) were treated with voriconazole and 31% (n = 168) with itraconazole. The median daily dose of both itraconazole and voriconazole used was 400mg. In a pooled analysis, AEs were observed in 36% (95% CI: 20-52%, N = 366) of patients on voriconazole and 25% (95% CI: 18 to 31%, N = 168) in those treated with itraconazole. Discontinuation rate due to AEs was the same for both drugs; 35% (47/366) and 35% (15/168) for voriconazole and itraconazole, respectively. There were 70 AEs reported with itraconazole use, the commonest being cardiotoxicity (29%). Skin AEs (28%) were the most frequent among the 204 AEs reported with voriconazole use. None of the studies compared the tolerability of itraconazole head-to-head with voriconazole.

CONCLUSIONS

AEs due itraconazole and voriconazole are common and may lead to discontinuation of treatment in a significant proportion of patients. This information can be used to educate patients prior to commencement of these antifungal therapies.

PROSPERO REGISTRATION NUMBER

CRD42020191627.

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.

Clinical outcomes of patients with chronic pulmonary aspergillosis managed surgically

OBJECTIVES

METHODS

All patients with CPA surgically treated at National Aspergillosis Centre (NAC), Manchester, UK (2007–2018), were retrospectively evaluated. Surgical procedures, underlying disorders, Aspergillus-IgG titres (ImmunoCap) and antifungal therapy were evaluated for symptom control, operative complications, CPA relapse and mortality.

RESULTS

A total of 61 patients with CPA (28 males, 33 females) were operated on primarily for antifungal therapy failure (51%, n = 31) and presumed lung malignancies (38%, n = 23). Procedures included lobectomy (64%, n = 39), wedge resection (28%, n = 17), segmentectomy (n = 3), pneumonectomy (n = 3) and decortication (n = 2). Overall, 25 (41%) patients relapsed, 26 months (standard deviation: 24.8 months) after surgery. Antifungal therapy before surgery (P = 0.002) or both before and after surgery (P = 0.005) were protective for relapse. The relapse rate within 3 years after surgery (33%, n = 20) was higher than the 3–10 years after surgery (8%, n = 5). At the end of follow-up, the median Aspergillus-IgG titre was lower than at relapse in 12 patients (67 vs 126 mg/l) (P = 0.016).

CONCLUSIONS

Surgery in these selected patients with CPA resulted in favourable outcomes. Relapse is common after surgical treatment of CPA but can be minimized with antifungal therapy, emphasizing the importance of an accurate diagnosis prior to surgery.