Analysis of bronchoalveolar lavage in allergic bronchopulmonary aspergillosis: divergent responses of antigen-specific antibodies and total IgE

Fractional exhaled nitric oxide, a potential biomarker for evaluating glucocorticoids treatment and prognosis in allergic bronchopulmonary aspergillosis

BACKGROUND

Allergic bronchopulmonary aspergillosis (ABPA) is characterized by enhanced TH2 inflammatory response. Fractional exhaled nitric oxide (FeNO) measurement has been used as a valuable tool in predicting the development and management of asthma, another typical TH2 inflammation. However, the clinical significance of FeNO in ABPA remains unclear.

OBJECTIVE

To investigate the association between FeNO and the prognosis of patients with ABPA to provide a basis for the use of FeNO in evaluating the efficacy of glucocorticoids in ABPA treatment.

METHODS

This study comprised 2 parts; 58 patients were enrolled in the retrospective study. Clinical indexes in patients with different prognoses were compared, and receiver operating characteristic curve analysis was used to determine the threshold value. The prospective observational study involved 61 patients who were regularly followed up at 4 to 6 weeks and 6 months since the initial treatment. Patients were grouped on the basis of baseline FeNO values; correlation analysis was performed in the clinical data.

RESULTS

Different prognoses were observed between patients with high and low baseline FeNO values, with a threshold value of 57 parts per billion. The percentage of Aspergillus fumigatus-specific IgE, percentage of positive A fumigatus-specific IgG, and relapse/exacerbation rate differed significantly between the high and low FeNO groups. Patients with higher FeNO needed longer treatment duration and showed shorter interval between glucocorticoid withdrawal and the next relapse/exacerbation.

CONCLUSION

Our findings indicate that the level of FeNO is associated with the prognosis of ABPA. It can serve as an independent and valuable biomarker for evaluating the effectiveness of glucocorticoid treatment.

Bronchoalveolar lavage as a diagnostic procedure: a review of known cellular and molecular findings in various lung diseases

Bronchoalveolar lavage (BAL) is a commonly used procedure in the evaluation of lung disease as it allows for sampling of the lower respiratory tract. In many circumstances, BAL differential cell counts have been reported to be typical of specific lung disorders. In addition, more specific diagnostic tests including molecular assays such as polymerase chain reaction (PCR) or enzyme-linked immunosorbent assay, special cytopathologic stains, or particular microscopic findings have been described as part of BAL fluid analysis. This review focuses on common cellular and molecular findings of BAL in a wide range of lung diseases. Since the performance of the first lung irrigation in 1927, BAL has become a common and important diagnostic tool. While some pulmonary disorders have a highly characteristic signature of BAL findings, BAL results alone often lack specificity and require interpretation along with other clinical and radiographic details. Development of new diagnostic assays is certain to reinforce the utility of BAL in the future. Our review of the BAL literature is intended to serve as a resource to assist clinicians in the care of patients with lung disorders.

A Case of Allergic Bronchopulmonary Aspergillosis (ABPA) in a Patient with a History of Cocaine Use and Tuberculosis

Aspergillosis refers to a spectrum of disorders that can occur due to colonization with the Aspergillus fungus. Allergic bronchopulmonary aspergillosis (ABPA) is an airway hypersensitivity reaction to the fungus that is almost exclusively seen in patients with cystic fibrosis or asthma. Here, we present a case of ABPA in a patient with a history of chronic cocaine use and tuberculosis and no history of asthma or cystic fibrosis. The patient had presented with progressively worsening dyspnea for three months as well as a 20-pound weight loss. Diagnosis was made with an elevated IgE against Aspergillus and chest CT findings, which included bronchiectasis and tree-in-bud nodular opacities. The patient was treated with IV methylprednisolone followed by a 4-day course of oral prednisone, with significant improvement. It is our hope to make healthcare providers aware of the potential presence of ABPA in chronic cocaine users and patients with tuberculosis, both of which are not traditionally associated with this condition.

Respiratory Allergic Disorders

Allergic asthma refers to a chronic reversible bronchoconstriction influenced by an allergic trigger, leading to symptoms of cough, wheezing, shortness of breath, and chest tightness. Allergic bronchopulmonary aspergillosis is a complex hypersensitivity reaction, often in patients with asthma or cystic fibrosis, occurring when bronchi become colonized by Aspergillus species. The clinical picture is dominated by asthma complicated by recurrent episodes of bronchial obstruction, fever, malaise, mucus production, and peripheral blood eosinophilia. Hypersensitivity pneumonitis is a syndrome associated with lung inflammation from the inhalation of airborne antigens, such as molds and dust.

Utility of IgE (total and Aspergillus fumigatus specific) in monitoring for response and exacerbations in allergic bronchopulmonary aspergillosis

The role of total and specific IgE in monitoring treatment responses in allergic bronchopulmonary aspergillosis (ABPA) remains poorly studied. Here in, we evaluate the utility of total and Aspergillus fumigatus specific IgE in the follow-up of ABPA. Eighty-one consecutive treatment-naïve patients of ABPA (acute stage) with pulmonary infiltrates and bronchiectasis underwent measurement of total and A. fumigatus specific IgE at baseline, after 8 weeks of glucocorticoid therapy, and during exacerbations. There was clinical and radiological improvement after treatment with median decline of total IgE by 51.9%. The total IgE declined by at least 35%, 25% and 20% in 69 (85.2%), 76 (93.6%) and 78 (96.3%) patients, respectively. On the other hand, the A. fumigatus specific IgE increased in 42 (51.9%) subjects, and the mean increase was 1.4%, after 8 weeks. Among 13 patients with exacerbation, 12 (92.3%) had a rise of total IgE by >50%. The A. fumigatus specific IgE increased in only five (38.5%) subjects during exacerbation. Thus, the total IgE is a useful test in monitoring treatment responses in ABPA while A. fumigatus specific IgE has limited utility.

T helper 2 response in allergic bronchopulmonary aspergillosis is not driven by specific Aspergillus antigens

Allergic bronchopulmonary aspergillosis (ABPA) is characterized by an allergic immunological response to Aspergillus fumigatus. In this study, we investigated whether certain Aspergillus antigens are more allergenic than others, as was postulated previously. We stimulated peripheral blood mononuclear cells from patients with ABPA with the classically described A. fumigatus allergens Aspf1, Aspf2, Aspf3, and Aspf4, as well as two other Aspergillus antigens, Crf1 and Catalase1. Activated CD4+ T cells displayed a T helper 2 phenotype with the production of IL-4 in response to stimulation with several of these different antigens. Immune responses were not limited to the classically described A. fumigatus allergens. In healthy individuals, we demonstrated a similar recognition profile to the different antigens, but in contrast the activated CD4+ T cells exerted a T helper 1 phenotype and mainly produced IFN-γ after stimulation with A. fumigatus antigens. In conclusion, irrespective of the A. fumigatus antigen, the T-cell immune response in patients with ABPA is skewed to a T helper 2 cytokine secretion profile.

Fungal sensitization in childhood persistent asthma is associated with disease severity

RATIONALE

Recent observations, especially in adults, suggest that asthma severity may be associated with fungal sensitization. Other studies suggest that some patients with severe asthma and fungal sensitization may benefit from anti-fungal therapy. Currently, the prevalence of fungal sensitization among children with severe asthma is not well characterized.

METHODS

We determined prevalence of fungal sensitization among children with moderate to severe persistent asthma and compared clinical characteristics between sensitized and non-sensitized children, including asthma severity, serum immunoglobulin E, and pulmonary function.

RESULTS

Of the 64 children enrolled, 25 (39%) had evidence of sensitization to one or more fungi. Nineteen of 25 (76%) children with fungal sensitization were categorized as severe persistent compared to 13 of 39 (33%) children without evidence of fungal sensitization (odds ratio = 6.33, 95% confidence interval 2.04-19.68, P = 0.0014). Of 32 severe persistent asthmatics, 19 (59%) demonstrated evidence of fungal sensitization. Serum immunoglobulin E was significantly higher (P < 0.001), and pulmonary function (including FEV1, FEV1/FVC, and FEF25-75%) significantly lower in the fungal-sensitized patients (P = 0.016, 0.0004, and 0.002, respectively). Bronchial biopsy of sensitized children revealed basement membrane thickening and eosinophil infiltration.

CONCLUSIONS

Fungal sensitization in children with persistent asthma is associated with disease severity. Almost 60% of our severe persistent asthma patients had evidence of fungal sensitization and, based on our previous studies, may be potential candidates for anti-fungal therapy.

The impact of Aspergillus fumigatus viability and sensitization to its allergens on the murine allergic asthma phenotype

Aspergillus fumigatus is a ubiquitously present respiratory pathogen. The outcome of a pulmonary disease may vary significantly with fungal viability and host immune status. Our objective in this study was (1) to assess the ability of inhaled irradiation-killed or live A. fumigatus spores to induce allergic pulmonary disease and (2) to assess the extent to which inhaled dead or live A. fumigatus spores influence pulmonary symptoms in a previously established allergic state. Our newly developed fungal delivery apparatus allowed us to recapitulate human exposure through repeated inhalation of dry fungal spores in an animal model. We found that live A. fumigatus spore inhalation led to a significantly increased humoral response, pulmonary inflammation, and airway remodeling in naïve mice and is more likely to induce allergic asthma symptoms than the dead spores. In contrast, in allergic mice, inhalation of dead and live conidia recruited neutrophils and induced goblet cell metaplasia. This data suggests that asthma symptoms might be exacerbated by the inhalation of live or dead spores in individuals with established allergy to fungal antigens, although the extent of symptoms was less with dead spores. These results are likely to be important while considering fungal exposure assessment methods and for making informed therapeutic decisions for mold-associated diseases.

Coexistence of allergic bronchopulmonary aspergillosis and allergic aspergillus sinusitis in a patient without clinical asthma

All patients with prolonged cough with a history of atopy, even if not clinically asthmatic, should be evaluated for allergic bronchopulmonary aspergillosis (ABPA); also, we suspect that we may miss the early diagnosis of ABPA if bronchial asthma is considered as a major criteria for the diagnosis of ABPA.

Allergic bronchopulmonary mycosis due to fungi other than Aspergillus: a global overview

Allergic bronchopulmonary mycosis (ABPM) is a hypersensitivity-mediated disease of worldwide distribution. We reviewed 143 reported global cases of ABPM due to fungi other than aspergilli. The commonest etiologic agent was Candida albicans, reported in 60% of the cases, followed by Bipolaris species (13%), Schizophyllum commune (11%), Curvularia species (8%), Pseudallescheria boydii species complex (3%) and rarely, Alternaria alternata, Fusarium vasinfectum, Penicillium species, Cladosporium cladosporioides, Stemphylium languinosum, Rhizopus oryzae, C. glabrata, Saccharomyces cerevisiae and Trichosporon beigelii. India accounted for about 47% of the globally reported cases of ABPM, attributed predominantly to C. albicans, followed by Japan (16%) where S. commune predominates, and the remaining one-third from the USA, Australia and Europe. Notably, bronchial asthma was present in only 32% of ABPM cases whereas its association with development of allergic bronchopulmonary aspergillosis (ABPA) is known to be much more frequent. The cases reviewed herein revealed a median IgE value threefold higher than that of ABPA, suggesting that the etiologic agents of ABPM incite a stronger immunological response than that by aspergilli in ABPA. ABPM is currently underdiagnosed, warranting comprehensive basic and clinical studies in order to elucidate its epidemiology and to devise a more effective therapy.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is caused by an exaggerated T(H)2 response to the ubiquitous mold Aspergillus fumigatus. ABPA develops in a small fraction of patients with cystic fibrosis and asthma, suggesting that intrinsic host defects play a major role in disease susceptibility. This article reviews current understanding of the immunopathology, clinical and laboratory findings, and diagnosis and management of ABPA. It highlights clinical and laboratory clues to differentiate ABPA from cystic fibrosis and asthma, which are challenging given clinical and serologic similarities. A practical diagnostic algorithm and management scheme to aid in the treatment of these patients is outlined.

Increased chitinase expression and fungal-specific antibodies in the bronchoalveolar lavage fluid of asthmatic children

BACKGROUND

Increasing evidence highlights the contribution of chitinases and fungal infection to the development of asthma.

OBJECTIVE

The purpose of this study was to characterize chitinase expression and serological markers of fungal infection in children with severe asthma.

METHODS

Bronchoalveolar lavage fluid (BALF) was collected from children undergoing clinically indicated flexible bronchoscopy. A diagnosis of asthma was confirmed by pulmonary function testing. BALF was tested for chitinase activity and YKL-40 (an enzymatically inactive chitinase) concentrations. Specimens were cultured for fungal organisms and tested for cryptococcal antigen by ELISA. IgG and IgA reactivity to whole extract fungal (Aspergillus fumigatus, Alternaria alternata, Cryptococcus neoformans and Candida albicans) proteins were determined by immunoblot assay.

RESULTS

Among the 37 patients studied, 30 were asthmatic and 7 were non-asthmatic. Asthmatics exhibited elevated serum IgE levels (median: 748 IU/mL, IQR: 219-1765 IU/mL). Chitinase activity was greater in the BALF of asthmatics (mean, 0.85 ± 1.2 U/mL) compared with non-asthmatics (mean: 0.23 ± 0.21 U/mL, P = 0.012). Likewise YKL-40 concentrations were higher in the BALF of asthmatics and correlated with chitinase activity. There was a trend towards increased fungal-specific IgG in the BALF of asthmatics compared with non-asthmatics and for C. albicans this difference reached statistical significance. IgA reactivity to C. neoformans and A. fumigatus was greater in the BALF of asthmatics compared with non-asthmatics.

CONCLUSIONS AND CLINICAL RELEVANCE

Compared with non-asthmatics, asthmatic children exhibited increased chitinase activity and increased YKL-40 levels in BALF. Increased IgG and IgA reactivity to fungal proteins in the BALF of asthmatics may reflect a local response to fungal infection. Our findings are consistent with and suggest a role for chitinases in asthma pathogenesis among Bronx children and provide serological evidence of an association between fungal infection and severe asthma.

Serum markers for allergic bronchopulmonary aspergillosis in cystic fibrosis: State of the art and further challenges

Allergic bronchopulmonary aspergillosis (ABPA), which results from hypersensitivity, primarily to Aspergillus, represents a severe complication in patients suffering from asthma or cystic fibrosis (CF). Since early treatment of ABPA is supposed to prevent long-term damages, ABPA has to be diagnosed promptly. However, this diagnosis is not straightforward due to clinical and radiological features of ABPA overlapping with those of CF. Despite ABPA specific diagnosis criteria proposed by the Cystic Fibrosis Foundation in 2003, making a definitive ABPA diagnosis in CF patients remains a challenge. Recent advances in the immunopathogenesis of ABPA have initiated the development of new serological tests, such as the recently reported detection of specific IgE to recombinant A. fumigatus allergens, or Thymus- and activation-regulated chemokine (TARC / CCL17), both of which are of value in the diagnosis of APBA. We review in this paper the serum markers that can advance ABPA diagnosis in CF patients, ranging from the well known criteria (anti-A. fumigatus IgE, IgG, and precipitins) to the recent biomarkers (IgE towards recombinant A. fumigatus allergens or TARC detection). Taking into account the up-dated physiopathology of ABPA, we discuss their place and their usefulness, especially TARC, to improve early ABPA detection and monitoring in CF patients.

Role of inhaled corticosteroids in the management of serological allergic bronchopulmonary aspergillosis (ABPA)

BACKGROUND AND AIM

The treatment of choice for allergic bronchopulmonary aspergillosis (ABPA) is oral corticosteroids (OCS). However, they are associated with numerous adverse effects. Inhaled corticosteroids (ICS) are associated with fewer side-effects; however, their role in the management of ABPA remains controversial. In this retrospective study, we evaluate the role of high doses of ICS in serological ABPA (ABPA-S).

METHODS

Patients with ABPA-S were treated with a combination of formoterol/budesonide (24-1600 micrograms per day), and followed up with history, physical examination, chest radiograph and total IgE levels at 6, 12, 18 and 24 weeks. Asthma control was evaluated using the Global Initiative for Asthma (GINA) criteria. OCS were initiated if the IgE levels continued to rise after six months of therapy with ICS.

RESULTS

There were 8 men and 13 women with a mean (SD) age of 39.3 (12.9) years. There was subjective improvement in all patients treated with ICS but none had complete control of asthma. After six months of therapy with ICS, the median IgE levels increased by 99.3%. After the initiation of OCS, there was complete resolution of asthma symptoms in 19 patients, and IgE levels fell by a median of 52.6% at six weeks. The median duration of follow-up was 15 months after OCS therapy. Eighteen patients achieved complete remission and three patients had a relapse in the first three months after stopping OCS. One patient required long-term OCS and was classified as glucocorticoid-dependent ABPA.

CONCLUSION

High doses of ICS alone have no role in the management of ABPA-S and should not be used as first-line therapy. In patients receiving OCS or alternate therapy, ICS can be used as an add-on therapy for the control of symptoms of asthma.

Eosinophils in innate immunity: an evolving story

Eosinophils are innate immune leukocytes found in relatively low numbers within the blood. Terminal effector functions of eosinophils, deriving from their capacity to release their content of tissue-destructive cationic proteins, have historically been considered primary effector mechanisms against specific parasites, and are likewise implicated in tissue damage accompanying allergic responses such as asthma. However, the past decade has seen dramatic advancements in the field of eosinophil immunobiology, revealing eosinophils to also be key participants in many other facets of innate immunity, from bridging innate and adaptive immune responses to orchestrating tissue remodeling events. Here, we review the multifaceted functions of eosinophils in innate immunity that are currently known, and discuss new avenues in this evolving story.

Noninvasive pulmonary Aspergillus infections

Aspergillus can cause several forms of pulmonary disease ranging from colonization to invasive aspergillosis and largely depends on the underlying lung and immune function of the host. This article reviews the clinical presentation, diagnosis, pathogenesis, and treatment of noninvasive forms of Aspergillus infection, including allergic bronchopulmonary aspergillosis (ABPA), aspergilloma, and chronic pulmonary aspergillosis (CPA). ABPA is caused by a hypersensitivity reaction to Aspergillus species and is most commonly seen in patients who have asthma or cystic fibrosis. Aspergillomas, or fungus balls, can develop in previous areas of cavitary lung disease, most commonly from tuberculosis. CPA has also been termed semi-invasive aspergillosis and usually occurs in patients who have underlying lung disease or mild immunosuppression.

[Refractory asthma: diagnosing allergic bronchopulmonary aspergillosis]

Allergic bronchopulmonary aspergillosis (ABPA) results from a twofold mechanism: Th2-like hypersensitivity reaction and bronchial colonization by Aspergillus fumigatus. This relatively rare disease occurs in immunocompetent patients in two very different situations: refractory asthma and cystic fibrosis. Diagnosis in asthma patients is relatively easy; it is based on the association of several criteria: clinical (recurrent exacerbations despite adequate therapy and a positive A. fumigatus skin prick-test), laboratory (inconsistent blood eosinophilia, high serum levels of total IgE, presence of A. fumigatus-specific IgE and IgG) and radiological (mainly central bronchiectasis, sometimes transitory pulmonary infiltrates). Diagnosis is more difficult in patients with cystic fibrosis because of the similarity of their various criteria. Long-term prognosis is good in the early stages of the illness, although the natural history and course of the disease are not fully understood. Early diagnosis and active screening for exacerbations are recommended to prevent bronchiectasis and progression to end-stage lung disease. Two drugs have shown their efficacy in treating ABPA: corticosteroids and itraconazole. They are recommended in acute exacerbations and should not be used as long-term therapy, except in corticosteroid-dependent asthma and in some cases of cystic fibrosis.

Allergic bronchopulmonary aspergillosis coupled with broncholithiasis in a non-asthmatic patient

Allergic bronchopulmonary aspergillosis (ABPA), an asthmatic disease, is caused primarily by hypersensitivity to Aspergillus species. ABPA is rarely observed in the absence of asthma, which is, in fact, the principle criterion for its diagnosis. Here, we report the case of a 36-yr-old woman without a history of bronchial asthma, who manifested a localized pneumonic consolidation, coupled with broncholithiasis. Pathologic examinations of bronchoscopic biopsy specimens and resected surgical specimens revealed features typical of ABPA. This is a very rare case of ABPA coupled with broncholithiasis in a non-asthmatic individual.

[IgE and respiratory disease]

INTRODUCTION

IgE is known to provide the biological basis for allergy and immediate hypersensitivity. However, recent data provide some evidence that IgE responses are involved in other inflammatory processes apart from allergy, including several respiratory diseases.

STATE OF THE ART

IgE binds to mast cells and basophils but also to other inflammatory cells, which are involved in non-allergic processes. IgE has a role in antigen presentation and is implicated in a number of other immune mechanisms. In the airways, IgE plays an important role in bronchial hyperactivity, even in the absence of an allergen. Epidemiological studies have demonstrated that IgE response is related not only to allergy but also to asthma symptoms, in the presence or absence of atopy, as well as exposure to cigarette smoke. IgE response is altered in several respiratory diseases including extrinsic and intrinsic asthma and allergic bronchopulmonary aspergillosis.

CONCLUSION AND PERSPECTIVES

Since anti-IgE monoclonal antibodies are now available for administration to humans, a better understanding of the IgE response may allow the identification of novel therapeutic targets in the field of respiratory disease.

Neutrophils regulate airway responses in a model of fungal allergic airways disease

Neutrophils infiltrate airway walls in patients with allergic airway diseases and in animal models of these illnesses, but their contribution to the pathogenesis of airway allergy is not established. We hypothesized that, in a mouse model of airway allergy to the ubiquitous environmental mold, Aspergillus fumigatus, airway neutrophils contribute to disease severity. Ab-mediated neutrophil depletion resulted in reduced airway hyperresponsiveness and remodeling, whereas conditional transgenic overexpression of the neutrophil chemotactic molecule, CXCL1, in airway walls resulted in worsened allergic responses. This worsened phenotype was associated with a marked increase in the number of airway neutrophils but not other lung leukocytes, including eosinophils and lymphocyte subsets, and depletion of neutrophils in sensitized mice with transgenic overexpression of CXCL1 resulted in attenuated airway responses. The number of lung neutrophils correlated with lung matrix metalloproteinase 9 (MMP-9) activity both in the context of neutrophil depletion and with augmented neutrophil recruitment to the airways. Although wild-type and MMP-9-deficient neutrophils homed to the inflamed airways to a similar extent, transfer of wild-type, but not MMP-9-deficient, neutrophils to MMP-9-deficient animals resulted in augmented allergic airway responses. Taken together, these data implicate neutrophils in the pathogenesis of fungal allergic airway disease.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) occurs in nonimmunocompromised patients and belongs to the hypersensitivity disorders induced by Aspergillus. Genetic factors and activation of bronchial epithelial cells in asthma or cystic fibrosis are responsible for the development of a CD(4)+Th2 lymphocyte activation and IgE, IgG and IgA-AF antibodies production. The diagnosis of ABPA is based on the presence of a combination of clinical, biological and radiological criteria. The severity of the disease is related to corticosteroid-dependant asthma or/and diffuse bronchiectasis with fibrosis. The treatment is based on oral corticosteroids for 6-8 weeks at acute phase or exacerbation and itraconazole is now recommended and validated at a dose of 200 mg/day for a duration of 16 weeks.

Pathogenesis of allergic bronchopulmonary aspergillosis and an evidence-based review of azoles in treatment

BACKGROUND

Allergic bronchopulmonary aspergillosis (ABPA) is a complex condition that affects people with asthma and cystic fibrosis (CF). It results from exposure to the fungus Aspergillus fumigatus, which leads to worsening airway inflammation and progressive damage to the lungs. The aim of this review is to outline the pathogenesis of the disorder, diagnostic criteria and to discuss the use of anti-fungal agents in its treatment.

METHODS

The Cochrane library of systematic reviews and the Cochrane database of controlled trials were searched for controlled trials on ABPA and its treatment in both asthma and CF. In addition, articles included within the reviews were examined separately, and a separate search carried out using Medline.

RESULTS

A systematic review for the use of azole anti-fungal agents in ABPA was identified for their use in both CF and non-CF-related disease. The review of ABPA alone identified two randomized-controlled trials of itraconazole in chronic disease. These trials demonstrated improvements in symptoms and immune activation, but were short-term trials and failed to show a significant change in lung function. No trials were identified in CF.

CONCLUSIONS

The use of anti-fungal agents in ABPA seems to be a rational one, with short-term efficacy demonstrated for the use of itraconazole. Further investigations are required to identify individuals who will benefit most from treatment and to establish the correct dose and means of delivering treatment in ABPA. Longer-term studies are required to demonstrate that treatment modifies the progressive decline in lung function seen with the disease.

Azoles for allergic bronchopulmonary aspergillosis associated with asthma

BACKGROUND

Allergic bronchopulmonary aspergillosis is hypersensitivity to the fungus Aspergillus fumigatus that complicates patients with asthma and cystic fibrosis. The mainstay of treatment for allergic bronchopulmonary aspergillosis remains oral corticosteroids, though this does not completely prevent exacerbations and may not prevent the decline in lung function.

OBJECTIVES

The purpose of this review was to determine the efficacy of azoles in the treatment of allergic bronchopulmonary aspergillosis.

SEARCH STRATEGY

We searched the Cochrane Airways Group Asthma trials register using the terms: (allergic bronchopulmonary aspergillosis OR aspergillosis OR allergic pulmonary aspergillosis OR allergic fungal and disease OR allergic mycotic and disease) AND (azole OR triazole OR itraconazole OR ketoconazole). Date of last search January 2003.

SELECTION CRITERIA

All controlled trials that assessed the effect of azole antifungal agents compared to placebo or other standard therapy for allergic bronchopulmonary aspergillosis were reviewed. Patients with cystic fibrosis were not included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Adverse effects information was collected from the trials.

MAIN RESULTS

Twelve trials were identified, but only three were prospective, randomised and controlled. A total of 94 participants were included. One demonstrated a reduction in immunological markers of disease activity and symptom scores using ketoconazole 400 mg daily for 12 months. There was no significant improvement in lung function. The other two examined the use of itraconazole for 16 weeks. In one there was a reduction in sputum eosinophils by 35% compared to 19% with placebo (p < 0.01). In the same trial, the number of exacerbations requiring oral corticosteroids was 0.4 per patient with itraconazole compared with 1.3 per patient with placebo (p < 0.03). Meta-analysis of data from both trials showed that itraconazole treated patients were more likely to have decline in serum IgE over 25% or more (Peto OR 3.30; 95% confidence intervals 1.30 to 8.15).

REVIEWERS' CONCLUSIONS

Itraconazole modifies the immunologic activation associated with allergic bronchopulmonary aspergillosis and improves clinical outcome, at least over the period of 16 weeks. Adrenal suppression with inhaled corticosteroids and itraconazole is a potential concern.

Azoles for allergic bronchopulmonary aspergillosis associated with asthma

BACKGROUND

Allergic bronchopulmonary aspergillosis is hypersensitivity to the fungus Aspergillus fumigatus that complicates patients with asthma and cystic fibrosis. The mainstay of treatment for allergic bronchopulmonary aspergillosis remains oral corticosteroids, though this does not completely prevent exacerbations and may not prevent the decline in lung function.

OBJECTIVES

The purpose of this review was to determine the efficacy of azoles in the treatment of allergic bronchopulmonary aspergillosis.

SEARCH STRATEGY

We searched the Cochrane Airways Group Asthma trials register using the terms: (allergic bronchopulmonary aspergillosis OR aspergillosis OR allergic pulmonary aspergillosis OR allergic fungal and disease OR allergic mycotic and disease) AND (azole OR triazole OR itraconazole OR ketoconazole). Date of last search January 2003.

SELECTION CRITERIA

All controlled trials that assessed the effect of azole antifungal agents compared to placebo or other standard therapy for allergic bronchopulmonary aspergillosis were reviewed. Patients with cystic fibrosis were not included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Adverse effects information was collected from the trials.

MAIN RESULTS

Twelve trials were identified, but only three were prospective, randomised and controlled. A total of 94 participants were included. One demonstrated a reduction in immunological markers of disease activity and symptom scores using ketoconazole 400 mg daily for 12 months. There was no significant improvement in lung function. The other two examined the use of itraconazole for 16 weeks. In one there was a reduction in sputum eosinophils by 35% compared to 19% with placebo (p < 0.01). In the same trial, the number of exacerbations requiring oral corticosteroids was 0.4 per patient with itraconazole compared with 1.3 per patient with placebo (p < 0.03). Meta-analysis of data from both trials showed that itraconazole treated patients were more likely to have decline in serum IgE over 25% or more (Peto OR 3.30; 95% confidence intervals 1.30 to 8.15).

REVIEWER'S CONCLUSIONS

Itraconazole modifies the immunologic activation associated with allergic bronchopulmonary aspergillosis and improves clinical outcome, at least over the period of 16 weeks. Adrenal suppression with inhaled corticosteroids and itraconazole is a potential concern.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) complicates asthma and cystic fibrosis. The survival factors in Aspergillus fumigatus that support saprophytic growth in bronchial mucus are not understood. Prednisone remains the most definitive treatment but need not be administered indefinitely. MHC II -restricted CD4(+) T( H)2 clones have been derived from patients with ABPA. The total serum IgE concentration is elevated sharply but is "nonspecific. " IgE serum isotypic antibodies to A fumigatus are useful in diagnosis; this is in contrast to the situation for patients with asthma without ABPA. High-resolution computed tomography of the chest demonstrates multiple areas of bronchiectasis in most patients with ABPA and is a useful radiologic tool. Some asthma control patients might have a few bronchiectatic airways, but not to the extent seen in or of the same character as those in ABPA. This review discusses clinical, radiologic, investigational, pathogenetic, and treatment issues of ABPA.

Cloning and expression of Aspergillus fumigatus allergen Asp f 16 mediating both humoral and cell-mediated immunity in allergic bronchopulmonary aspergillosis (ABPA)

BACKGROUND

Aspergillus fumigatus, a ubiquitous fungus, is responsible for a number of lung disorders in atopic and non-atopic individuals. Standardized, pure, and relevant allergens are desirable for reliable immunodiagnosis of the disease and to understand the structural and functional properties of these allergens and the role they play in causing ABPA.

OBJECTIVE

Molecular cloning and characterization of a relevant allergen from A. fumigatus cDNA library.

MATERIALS AND METHODS

A cDNA library was constructed from 96 h old mycelium of A. fumigatus using lambda ZAP expression vector. A novel gene encoding an A. fumigatus allergen was identified by screening the library with sera from ABPA patients. The gene was cloned and the allergen over-expressed in Escherichia coli. This recombinant allergen, Asp f 16, was evaluated in ELISA and Western blots using sera from patients and normal subjects and peripheral blood mononuclear cells (PBMC) for antigen-induced stimulation.

RESULTS

Seventy percent of the patients with ABPA demonstrated high levels of serum IgE antibodies to Asp f 16, a 43-kDa protein, whereas patients with allergic asthma, Aspergillus skin test-positive asthmatics without clinical evidence of ABPA, and normal controls failed to show Asp f 16-specific IgE binding by ELISA. The deduced amino acid sequences of Asp f 16 showed extensive sequence homology to 30.6-kDa Asp f 9 at the N-terminal region of the protein. PBMC from the majority of patients with ABPA exhibited significant proliferation with the recombinant Asp f 16 allergen.

CONCLUSION

Specific humoral and cell-mediated immune responses of Af-sensitized patients against Asp f 16 suggest its usefulness in the immunodiagnosis of hypersensitivity diseases due to Af and understanding the pathophysiology of ABPA.

Allergic bronchopulmonary aspergillosis: new concepts of pathogenesis and treatment

Allergic bronchopulmonary aspergillosis (ABPA) is a condition that results from a hypersensitivity reaction to the fungus Aspergillus fumigatus. The purpose of the present review is to examine the pathogenesis of this condition and the evidence for treatments available. Allergic bronchopulmonary aspergillosis is characterized by an intense airway inflammation with eosinophils and the formation of mucus plugs. Clinically, there are periods of exacerbation and remission that may lead to proximal bronchiectasis and fibrotic lung disease. New evidence confirms the role of intense airway inflammation with eosinophils, but also suggests a role for interleukin (IL)-8/neutrophil-mediated inflammation in this process, and the potential deficiency of anti-inflammatory cytokines such as reduced IL-10. Treatment for ABPA has so far focused on corticosteroids to suppress eosinophilic airway inflammation. An expanding knowledge of the pathology of ABPA also suggests other therapies may be of potential benefit, particularly the use of azole antifungal agents. Allergic bronchopulmonary aspergillosis is itself an important complication of asthma and cystic fibrosis. A greater understanding of the condition is required to improve management and well-designed clinical trials need to be carried out to critically assess new and current treatments. In addition, the information gained from the studies of its pathogenesis has the potential to benefit our understanding of the disease processes in asthma and bronchiectasis.

Rise in total IgE as an indicator of allergic bronchopulmonary aspergillosis in cystic fibrosis

BACKGROUND

Allergic bronchopulmonary aspergillosis is a serious complication of cystic fibrosis and may be difficult to diagnose. The aim of this study was to define the usefulness of measuring total IgE compared with other major criteria in the diagnosis of allergic bronchopulmonary aspergillosis in children with cystic fibrosis.

METHODS

A retrospective analysis was carried out of the case records of 160 children attending a tertiary referral paediatric cystic fibrosis clinic.

RESULTS

Sixteen children had a total IgE level above 500 IU/ml. Eleven children had six or more other major criteria and were considered to have allergic bronchopulmonary aspergillosis. These 11 children had a fourfold rise in IgE in association with clinical deterioration. A further child had a fourfold rise in IgE to 341 IU/l, and was also thought to have allergic bronchopulmonary aspergillosis. Eleven had a fall in IgE with successful treatment; one patient died with uncontrolled disease. Only one of these 12 children had negative precipitins to Aspergillus fumigatus. The five children with a raised IgE not thought to have bronchopulmonary aspergillosis had four or fewer major criteria and were not treated; none had positive precipitins.

CONCLUSIONS

A fourfold rise in total IgE, particularly to above 500 IU/ml, is strongly suggestive of the diagnosis of allergic bronchopulmonary aspergillosis in children with cystic fibrosis. The measurement of total IgE has the merit of being simple to perform and objective. Positive aspergillus precipitins provide useful confirmatory evidence. These two criteria, taken in conjunction with clinical deterioration and new radiological shadowing, allow simplification of the diagnosis of allergic bronchopulmonary aspergillosis in cystic fibrosis.

Experimental allergic bronchopulmonary aspergillosis in the mouse: immunological and histological features

C57BL/6 mice treated with intranasal instillation of 100 micrograms of Aspergillus antigen three times a week developed a pulmonary eosinophilia, observed in the bronchoalveolar lavage (BAL) and on histopathological examination. At week 3, the instillation of Aspergillus antigen provoked a 10-fold increase in the BAL cell number and eosinophils were the predominant inflammatory cells (66.4%). Histopathological findings showed focal alveolar lesions with peribronchial and perivascular infiltration of lymphoid cells, numerous eosinophils, epithelioid cells, and granulomas with giant cells. Increases in total IgE and IgG1 levels in BAL fluid (33-fold and 14-fold) and serum (67-fold and 8-fold) were observed also (P < 0.05). IgG1 specific to Aspergillus fumigatus (Af) was detected only in the antigen-treated mice. At 12 weeks, there was a persistent but less intense eosinophilia both in BAL and on histopathological examination accompanied by steadily elevated total IgE and total IgG1 and a higher level of specific IgG1-Af in BAL fluids and sera. No bronchocentric granulomatosis, mucoid impaction nor bronchiectasis could be observed. Data from the study described here showed that in mice repeated exposure to Aspergillus antigen leads to a strong inflammatory pulmonary response, characterized by remarkable pulmonary eosinophilia and elevations of total IgE, total IgG1 and specific IgG1-Af in both BAL and serum, which are the hallmarks of human allergic bronchopulmonary aspergillosis also. However, this inflammation did not induce the chronic histological features of the human disease.