Allergic bronchopulmonary aspergillosis from a contaminated dump site

ABPA and AFRS: addressing prevalence, early diagnosis, allergens, and occupational concerns

OBJECTIVE

This study aimed to comprehensively investigate the prevalence of ABPA and AFRS, scrutinize existing diagnostic criteria and immunoassays, pinpoint their limitations, highlight ABPA as an occupational health implication, and identify suggestive measures to improve ABPA diagnosis in the context of Occupational Health Nursing and primary healthcare.

DATA SOURCES

The data sources such as PubMed, Health and Safety Science Abstracts, OSH Update, Medline, and Google Scholar were searched.

STUDY SELECTIONS

All published studies in the English language from 1990 till Oct, 2023 using Mesh terms keywords "Allergic bronchopulmonary aspergillosis," "Allergic fungal rhinosinusitis," "Signs and Symptoms," "Rapid Diagnostic Tests," "Diagnosis," "Occupational Health," "Occupational Health Nursing," "Prevalence," "Allergens" following "Boolean operators" search strategy were selected.

RESULTS

This review succinctly covered signs, symptoms, and prevalence data concerning ABPA and AFRS. It briefly discussed existing diagnostic criteria and immunoassays, highlighted factors influencing the assay's variability, and underscored the role and scope of specific allergens toward improved, simple, and early ABPA diagnosis. ABPA as a neglected occupational health concern was emphasized, and the importance of RDTs in the context of healthcare professionals and OHNs was stated. Finally, this study suggested analyzing the impact of compromised post-pandemic immune status and the use of immunosuppressive drugs on ABPA prevalence among vulnerable communities and occupations.

CONCLUSION

To conclude, global and Indian ABPA and AFRS prevalence data, factors influencing existing assay variability, and the scope of improvement in RDTs for ABPA diagnosis in the background of primary healthcare professionals and OHNs were addressed.

Revised ISHAM-ABPA working group clinical practice guidelines for diagnosing, classifying and treating allergic bronchopulmonary aspergillosis/mycoses

BACKGROUND

The International Society for Human and Animal Mycology (ISHAM) working group proposed recommendations for managing allergic bronchopulmonary aspergillosis (ABPA) a decade ago. There is a need to update these recommendations due to advances in diagnostics and therapeutics.

METHODS

An international expert group was convened to develop guidelines for managing ABPA (caused by Aspergillus spp.) and allergic bronchopulmonary mycosis (ABPM; caused by fungi other than Aspergillus spp.) in adults and children using a modified Delphi method (two online rounds and one in-person meeting). We defined consensus as ≥70% agreement or disagreement. The terms "recommend" and "suggest" are used when the consensus was ≥70% and <70%, respectively.

RESULTS

We recommend screening for A. fumigatus sensitisation using fungus-specific IgE in all newly diagnosed asthmatic adults at tertiary care but only difficult-to-treat asthmatic children. We recommend diagnosing ABPA in those with predisposing conditions or compatible clinico-radiological presentation, with a mandatory demonstration of fungal sensitisation and serum total IgE ≥500 IU·mL-1 and two of the following: fungal-specific IgG, peripheral blood eosinophilia or suggestive imaging. ABPM is considered in those with an ABPA-like presentation but normal A. fumigatus-IgE. Additionally, diagnosing ABPM requires repeated growth of the causative fungus from sputum. We do not routinely recommend treating asymptomatic ABPA patients. We recommend oral prednisolone or itraconazole monotherapy for treating acute ABPA (newly diagnosed or exacerbation), with prednisolone and itraconazole combination only for treating recurrent ABPA exacerbations. We have devised an objective multidimensional criterion to assess treatment response.

CONCLUSION

We have framed consensus guidelines for diagnosing, classifying and treating ABPA/M for patient care and research.

Toxicity studies of Aspergillus fumigatus administered by inhalation to B6C3F1/N mice (revised)

Aspergillus fumigatus is a thermotolerant, soil-borne fungal species that is ubiquitous in the environment. Mold was nominated to the National Toxicology Program (NTP) by a private individual due to suspected adverse health effects associated with personal exposure in indoor and occupational settings. A. fumigatus is of particular concern in the biowaste industry as the species can contaminate self-heating compost piles. Because of this potential for personal and occupational exposure and the lack of available toxicity data, toxicity studies were conducted in which male and female B6C3F1/N mice were exposed to A. fumigatus conidia (spores) two times a week for 3 months. All in-life procedures, including inhalation exposure, test article preparation, and hematology analysis, were completed by the National Institute for Occupational Safety and Health (NIOSH, Morgantown, WV). Battelle (Columbus, OH) conducted terminal necropsies, measured terminal body and organ weights, and evaluated gross lesions on-site at NIOSH. Tissue processing and histopathology were completed at Battelle. Grocott's methenamine silver (GMS) staining was performed at NIOSH. Genetic toxicology studies on mouse peripheral blood erythrocytes were conducted by Integrated Laboratory Systems, LLC (Research Triangle Park, NC). (Abstract Abridged).

Risk of respiratory hospital admission associated with modelled concentrations of Aspergillus fumigatus from composting facilities in England

Bioaerosols have been associated with adverse respiratory-related health effects and are emitted in elevated concentrations from composting facilities. We used modelled Aspergillus fumigatus concentrations, a good indicator for bioaerosol emissions, to assess associations with respiratory-related hospital admissions. Mean daily Aspergillus fumigatus concentrations were estimated for each composting site for first full year of permit issue from 2005 onwards to 2014 for Census Output Areas (COAs) within 4 km of 76 composting facilities in England, as previously described (Williams et al., 2019). We fitted a hierarchical generalized mixed model to examine the risk of hospital admission with a primary diagnosis of (i) any respiratory condition, (ii) respiratory infections, (iii) asthma, (iv) COPD, (v) diseases due to organic dust, and (vi) Cystic Fibrosis, in relation to quartiles of Aspergillus fumigatus concentrations. Models included a random intercept for each COA to account for over-dispersion, nested within composting facility, on which a random intercept was fitted to account for clustering of the data, with adjustments for age, sex, ethnicity, deprivation, tobacco sales (smoking proxy) and traffic load (as a proxy for traffic-related air pollution). We included 249,748 respiratory-related and 3163 Cystic Fibrosis hospital admissions in 9606 COAs with a population-weighted centroid within 4 km of the 76 included composting facilities. After adjustment for confounders, no statistically significant effect was observed for any respiratory-related (Relative Risk (RR) = 0.99; 95% Confidence Interval (CI) 0.96-1.01) or for Cystic Fibrosis (RR = 1.01; 95% CI 0.56-1.83) hospital admissions for COAs in the highest quartile of exposure. Similar results were observed across all respiratory disease sub-groups. This study does not provide evidence for increased risks of respiratory-related hospitalisations for those living near composting facilities. However, given the limitations in the dispersion modelling, risks cannot be completely ruled out. Hospital admissions represent severe respiratory episodes, so further study would be needed to investigate whether bioaerosols emitted from composting facilities have impacts on less severe episodes or respiratory symptoms.

A case of allergic bronchopulmonary aspergillosis in a 43-year-old farmer following single high level exposure to organic dust with symptomatic remission and radiological resolution after early diagnosis and treatment

Allergic bronchopulmonary aspergillosis (ABPA) is an uncommon lung condition associated with development or worsening of asthma symptoms, distinctive radiological and serological findings. It is thought to be the consequence of chronic colonization of the airways in individuals with pre-existing atopic conditions. We present a case unique in the literature of the development of ABPA in an individual without pre-existing atopic disease following a single high level exposure to organic dust. Early treatment was associated with complete symptomatic remission and significant resolution of bronchiectatic changes.

Aeromycological analysis of allergenic airborne fungi in Qazvin, Iran

Background and Purpose:

Airborne fungi are one of the most important agents responsible for triggering allergicreactions such as rhinitis and severe asthma. This study was conducted to analyze and monitor the prevalence and distribution patterns of atmospheric fungal aerosols in the air of Qazvin during winter of 2012.

Materials and Methods:

In the current descriptive study, the incidence and diversity of potentially allergenic airborne fungi were determined using two times sampling interval in 25 different locations of Qazvin city by Petri dish trappingtechnique and exposure of 10- cm diameter plates of Sabouraud’s dextrose agar medium plus chloramphenicol to the air.

Results:

A total of 2867 fungal colonies were counted on 156 Petri dishes. Of the identified 18 microfungi genera,Cladosporium spp. was the most frequently isolated genera representing 30.9% of isolates, followed by 30.9% Penicillium spp. (27.3%), Aspergillus spp %) . (24.5 , Alternaria spp. (3.3%), Rhizopus spp. (3.1%), and other fungal genera.

Conclusion:

The high prevalence, high quantity and variety of allergenic airborne fungi in the air of Qazvin showed that people residing in this area are exposed to health hazards. Furthermore, reduction of exposure to bio-aerosols containing these outdoor fungi is necessary to improve the health of individuals, especially those sensitive to fungal-induced diseases like asthma.

Respiratory Health in Waste Collection and Disposal Workers

Waste management, namely, collection, transport, sorting and processing, and disposal, is an issue of social concern owing to its environmental impact and effects on public health. In fact, waste management activities are carried out according to procedures that can have various negative effects on the environment and, potentially, on human health. The aim of our study was to assess the potential effects on respiratory health of this exposure in workers in the waste management and disposal field, as compared with a group of workers with no occupational exposure to outdoor pollutants. The sample consisted of a total of 124 subjects, 63 waste collectors, and 61 office clerks. Informed consent was obtained from all subjects before inclusion in the study. The entire study population underwent pulmonary function assessments with spirometry and completed two validated questionnaires for the diagnosis of rhinitis and chronic bronchitis. Statistical analyses were performed using STATA 13. Spirometry showed a statistically significant reduction in the mean Tiffenau Index values in the exposed workers, as compared with the controls, after adjusting for the confounding factors of age, BMI, and smoking habit. Similarly, the mean FEV1 values were lower in the exposed workers than in the controls, this difference being again statistically significant. The FVC differences measured in the two groups were not found to be statistically significant. We ran a cross-sectional study to investigate the respiratory health of a group of workers in the solid waste collection and disposal field as compared with a group of office workers. In agreement with most of the data in the literature, our findings support the existence of a prevalence of respiratory deficits in waste disposal workers. Our data suggest the importance of adopting preventive measures, such as wearing specific individual protection devices, to protect this particular category of workers from adverse effects on respiratory health.

Respiratory hospital admission risk near large composting facilities

BACKGROUND

Large-scale composting can release bioaerosols in elevated quantities, but there are few studies of health effects on nearby communities.

METHODS

A cross-sectional ecological small area design was used to examine risk of respiratory hospital admissions within 2500m of all 148 English large-scale composting facilities in 2008-10. Statistical analyses used a random intercept Poisson regression model at Census Output Area (COA) level (mean population 310). Models were adjusted for age, sex, deprivation and tobacco sales.

RESULTS

Analysing 34,963 respiratory hospital admissions in 4656 COAs within 250-2500m of a site, there were no significant trends using pre-defined distance bands of >250-750m, >750-1500m and >1500-2500m. Using a continuous measure of distance, there was a small non-statistically significant (p=0.054) association with total respiratory admissions corresponding to a 1.5% (95% CI: 0.0-2.9%) decrease in risk if moving from 251m to 501m. There were no significant associations for subgroups of respiratory infections, asthma or chronic obstructive pulmonary disease.

CONCLUSION

This national study does not provide evidence for increased risks of respiratory hospital admissions in those living beyond 250m of an outdoor composting area perimeter. Further work using better measures of exposure and exploring associations with symptoms and disease prevalence, especially in vulnerable groups, is recommended to support regulatory approaches.

Exposures and health outcomes in relation to bioaerosol emissions from composting facilities: a systematic review of occupational and community studies

The number of composting sites in Europe is rapidly increasing, due to efforts to reduce the fraction of waste destined for landfill, but evidence on possible health impacts is limited. This article systematically reviews studies related to bioaerosol exposures within and near composting facilities and associated health effects in both community and occupational health settings. Six electronic databases and bibliographies from January 1960 to July 2014 were searched for studies reporting on health outcomes and/or bioaerosol emissions related to composting sites. Risk of bias was assessed using a customized score. Five hundred and thirty-six papers were identified and reviewed, and 66 articles met the inclusion criteria (48 exposure studies, 9 health studies, 9 health and exposure studies). Exposure information was limited, with most measurements taken in occupational settings and for limited time periods. Bioaerosol concentrations were highest on-site during agitation activities (turning, shredding, and screening). Six studies detected concentrations of either Aspergillus fumigatus or total bacteria above the English Environment Agency's recommended threshold levels beyond 250 m from the site. Occupational studies of compost workers suggested elevated risks of respiratory illnesses with higher bioaerosol exposures. Elevated airway irritation was reported in residents near composting sites, but this may have been affected by reporting bias. The evidence base on health effects of bioaerosol emissions from composting facilities is still limited, although there is sufficient evidence to support a precautionary approach for regulatory purposes. While data to date are suggestive of possible respiratory effects, further study is needed to confirm this and to explore other health outcomes.

A questionnaire-based study on the role of environmental factors in allergic bronchopulmonary aspergillosis

Background and Aims:

Allergic bronchopulmonary aspergillosis (ABPA) is an immunological disorder caused by hypersensitivity against Aspergillus fumigatus. The pathogenesis of ABPA remains unknown. Few studies have investigated the role of environmental factors in pathogenesis of ABPA. Herein, we investigate the role of environmental factors in ABPA.

Materials and Methods:

In this prospective case-control study, consecutive patients with asthma (Aspergillus sensitized and unsensitized) and ABPA were investigated using a standardized questionnaire to enquire into their demographic characteristics, clinical details, exposure to organic matter and living conditions (home environment, presence of moisture in the walls, and others). Asthma severity and control was assessed using the 2002 The Global Initiative for Asthma (GINA) recommendations and asthma control test, respectively.

Results:

During the study period, 202 subjects of asthma (103 and 99 Aspergillus unsensitized and sensitized asthma, respectively) and 101 ABPA with a mean (SD) age of 35.3 (14.7) years were included. The baseline characteristics were similar in the two groups except for a higher prevalence of severe persistent asthma in the ABPA group (79% vs. 44%, P = 0.0001). No significant differences in environmental factors were noted in the ABPA population compared to asthmatic patients except for a higher rural residence in ABPA (47% vs. 66%, P = 0.007).

Conclusions:

The study found no significant environmental differences in ABPA compared to asthmatic patients. It is likely that environmental factors are not the primary pathogenetic factors in causation of ABPA.

Allergic bronchopulmonary aspergillosis in asthma: epidemiological, clinical and therapeutic issues

Allergic bronchopulmonary aspergillosis (ABPA) is a complex pulmonary disorder caused by immunologic reactions to antigens released by Aspergillus fumigatus, a ubiquitous fungi colonizing the tracheobronchial tree of asthmatic patients. The clinical presentation is usually poorly controlled asthma, recurrent pulmonary opacities and bronchiectasis. The prevalence of ABPA in asthma clinics may be as high as 13% with a global burden of almost 5 million patients. A. fumigatus-specific IgE level is the most sensitive test in diagnosis of ABPA, and all asthmatic patients should be routinely screened with A. fumigatus-specific IgE levels for early diagnosis. The goals of managing ABPA include control of asthma, prevention and treatment of acute exacerbations, and preventing the development or progression of bronchiectasis. Glucocorticoids are the treatment of choice with itraconazole reserved for those with recurrent exacerbations and glucocorticoid-dependent disease. There is a dire need for newer treatment approaches including oral antifungal agents and immunomodulatory therapy.

Aspergillus-associated airway disease, inflammation, and the innate immune response

Aspergillus moulds exist ubiquitously as spores that are inhaled in large numbers daily. Whilst most are removed by anatomical barriers, disease may occur in certain circumstances. Depending on the underlying state of the human immune system, clinical consequences can ensue ranging from an excessive immune response during allergic bronchopulmonary aspergillosis to the formation of an aspergilloma in the immunocompetent state. The severest infections occur in those who are immunocompromised where invasive pulmonary aspergillosis results in high mortality rates. The diagnosis of Aspergillus-associated pulmonary disease is based on clinical, radiological, and immunological testing. An understanding of the innate and inflammatory consequences of exposure to Aspergillus species is critical in accounting for disease manifestations and preventing sequelae. The major components of the innate immune system involved in recognition and removal of the fungus include phagocytosis, antimicrobial peptide production, and recognition by pattern recognition receptors. The cytokine response is also critical facilitating cell-to-cell communication and promoting the initiation, maintenance, and resolution of the host response. In the following review, we discuss the above areas with a focus on the innate and inflammatory response to airway Aspergillus exposure and how these responses may be modulated for therapeutic benefit.

Link between CFTR mutations and ABPA: a systematic review and meta-analysis

Summary  There is a biological plausibility on the link between cystic fibrosis transmembrane conductance regulator (CFTR) mutations and allergic bronchopulmonary aspergillosis (ABPA). The aim of the systematic review was to investigate this link by determining the frequency of CFTR mutations in ABPA. We searched the PubMed and EmBase databases for studies reporting CFTR mutations in ABPA. We pooled the odds ratio (OR) and 95% confidence intervals (CI) from individual studies using both fixed and random effects model. Statistical heterogeneity was evaluated using the I(2) test and the Cochran-Q statistic. Publication bias was assessed using both graphical and statistical methods. Our search yielded four studies (79 ABPA, 268 controls). The odds of encountering CFTR mutation was higher in ABPA compared with the control group (OR 10.39; 95% CI, 4.35-24.79) or the asthma population (OR 5.53; 95% CI 1.62-18.82). There was no evidence of statistical heterogeneity or publication bias. There is a possible pathogenetic link between CFTR mutations and ABPA. However, because of the small numbers of patients, further studies are required to confirm this finding. Future studies should adopt a uniform methodology and should screen for the entire genetic sequence of the CFTR gene.

Bioaerosol in composting facilities: occupational health risk assessment

This research found evidence of an association between occupational exposure to bioaerosols in composting plants and health outcome occurrence in exposed workers. An occupational exposure assessment in six composting plants was performed to better characterize personal exposure levels and evaluate associated health risk in workers. Sampling results showed large ranges of concentrations of dust, bacteria, molds, and endotoxin in ambient air and in personal samples, both when driving a front-end loader and when cleaning, monitoring, and performing maintenance tasks. Mean personal exposure levels were high at 100 to more than 10,000 times higher than outdoor background levels and fully consistent with occurrence of inflammatory and allergic respiratory outcomes among workers. Engineering control, personal protection, and education and training programs for employees, health, and safety officials, and occupational physicians are being developed and implemented.

Allergic bronchopulmonary aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is an immunologic pulmonary disorder caused by hypersensitivity to Aspergillus fumigatus. Clinically, a patient presents with chronic asthma, recurrent pulmonary infiltrates, and bronchiectasis. The population prevalence of ABPA is not clearly known, but the prevalence in asthma clinics is reported to be around 13%. The disorder needs to be detected before bronchiectasis has developed because the occurrence of bronchiectasis is associated with poorer outcomes. Because many patients with ABPA may be minimally symptomatic or asymptomatic, a high index of suspicion for ABPA should be maintained while managing any patient with bronchial asthma whatever the severity or the level of control. This underscores the need for routine screening of all patients with asthma with an Aspergillus skin test. Finally, there is a need to update and revise the criteria for the diagnosis of ABPA. This review summarizes the advances in the diagnosis and management of ABPA using a systematic search methodology.

Effects of bioaerosol polluted outdoor air on airways of residents: a cross sectional study

BACKGROUND

Bioaerosol pollution of workplace and home environments mainly affects airways and mucous membranes. The effect of environmental outdoor residential bioaerosol pollution, for example, livestock holdings, farming, and waste disposal plants, is unclear.

AIMS

To investigate the perceived health of residents living in areas with measurable outdoor bioaerosol pollution (for example, spores of Aspergillus fumigatus and actinomycetes), and effects of accompanying odours.

METHODS

In a cross sectional study, double blinded to ongoing microbial measurements, doctors collected 356 questionnaires from residents near a large scale composting site, and from unexposed controls in 1997. Self reported prevalence of health complaints during the past year, doctors' diagnoses, as well as residential odour annoyance were assessed. Microbiological pollution was measured simultaneously in residential outdoor air.

RESULTS

Concentrations of >10(5) colony forming units of thermophilic actinomycetes, moulds, and total bacteria/m(3) air were measured 200 m from the site, dropping to near background concentrations within 300 m. Positive adjusted associations were observed for residency within 150-200 m from the site versus unexposed controls for self reported health complaints: "waking up due to coughing", odds ratio (OR) 6.59 (95% confidence interval (CI) 2.57 to 17.73); "coughing on rising or during the day", OR 3.18 (95% CI 1.24 to 8.36); "bronchitis", OR 3.59 (95% CI 1.40 to 9.4); and "excessive tiredness", OR 4.27 (95% CI 1.56 to 12.15). Reports of irritative airway complaints were associated with residency in the highest bioaerosol exposure, 150-200 m (versus residency >400-500 m) from the site, and period of residency more than five years, but not residential odour annoyance. Lifetime prevalence of self reported diseases did not differ with exposure.

CONCLUSIONS

Bioaerosol pollution of residential outdoor air can occur in concentrations found in occupational environments. For the first time residents exposed to bioaerosol pollution were shown to report irritative respiratory complaints similar to mucous membrane irritation independently of perceived odours.

Upper airway inflammation and respiratory symptoms in domestic waste collectors

OBJECTIVES

To compare respiratory symptoms and upper airway inflammation in domestic waste collectors and controls, and to find the association between measures of upper airway inflammation on the one hand and exposure concentrations of organic dust or respiratory symptoms on the other hand.

METHODS

In a cross sectional study among 47 waste collectors and 15 controls, questionnaire data on respiratory symptoms were collected. Nasal lavage (NAL), to assess upper airway inflammation, was performed before and after a work shift at the beginning and at the end of the working week. In NAL fluid, cells were counted and differentiated and concentrations of interleukin 6 (IL6), IL8, tumour necrosis factor-alpha (TNF alpha), and IL1 beta were measured. In collectors, inhalable dust samples were collected in which bacterial endotoxin and mould beta(1-->3)-glucan were assessed.

RESULTS

Prevalence of respiratory symptoms was higher in waste collectors than in controls. Geometric mean exposure concentrations were 0.58 mg/m(3) for dust, 39 EU/m(3) for endotoxin, and 1.3 microg/m(3) for beta(1-->3)-glucan. At the end of the week collectors had higher concentrations of total cells and IL8 in NAL before and after a shift than controls (cells, before 1.9-fold p<0.10, after 3.3-fold p<0.01; IL8, before and after 1.8-fold p<0.05), and after/before work shift ratios of total cells were also higher (2.3-fold p=0.06) in collectors than in controls. Cells in NAL fluid consisted predominantly of neutrophils and epithelial cells, whereas eosinophils and mononuclear cells were rarely found. Exposure to dust and endotoxin was associated with concentrations of IL8 after the shift (p<0.05). Increased concentrations of IL8 (p<0.05) and total cells (p<0.10) after the shift were associated with respiratory symptoms. Concentrations of IL6, TNF alpha, and IL1 beta were not associated with waste collecting, symptoms, or exposure.

CONCLUSIONS

Waste collectors show signs of increased upper airway inflammation and respiratory symptoms compared with controls. Exposure to organic dust probably underlies the inflammation mediated by neutrophils that result in respiratory symptoms.

Upper airway inflammation assessed by nasal lavage in compost workers: A relation with bio-aerosol exposure

BACKGROUND

Exposure to microbial agents in the composting industry may cause work related airway inflammation. Nasal lavage (NAL) has been proposed as a noninvasive method to assess such effects in population studies.

METHODS

Pre- and post-shift NAL were performed in the workers of a compost plant visited in 1995 (n = 14) and 1996 (n=15), of whom only four participated in both surveys. Total cells, cytokines and other inflammation markers were measured in NAL fluid, and pre-shift levels and post/pre concentration ratios were compared with NAL results obtained in the same periods in 10 and 9 controls, respectively, and with levels of airborne exposure to microbial agents endotoxin and beta(1,3)-glucan as measured in personal air samples.

RESULTS

Job-title specific exposure levels in the first survey ranged from 75 to 527 EU/m(3) for endotoxin and from 0.54 to 4.85 microg/m(3) for beta(1,3)-glucan. In the second survey these values were lower, 29-285 EU/m(3) and 0.36-4.44 microg/m(3), respectively. In the first survey pre-shift NAL concentrations of total cells, MPO, IL-8, NO and albumin were significantly (1.1-4.8 fold) higher in compost workers than in controls. Post/pre ratios for various markers were significantly (1.2-3.2 fold) higher in compost workers in both surveys. NAL cells were mainly neutrophils, while eosinophils were only incidentally observed. A weak relation with exposure was found for pre-shift levels of MPO, uric acid and urea in the first survey.

CONCLUSIONS

Occupational exposure of compost workers may cause acute and possibly (sub-)chronic inflammatory reactions in the upper airways, presumably induced by non-allergenic pro-inflammatory agents like endotoxins and beta(1, 3)-glucans.

N-acetylcysteine inhibits germination of conidia and growth of Aspergillus spp. and Fusarium spp

N-Acetylcysteine inhibited hyphal growth and germination of conidia of Aspergillus spp. and Fusarium spp. N-Acetylcysteine inhibited conidial germination as well as or better than L-cysteine. Cysteine-related compounds may provide a potential therapeutic strategy against agriculturally and medically important fungal pathogens.

Particulate Aspergillus fumigatus antigens elicit a TH2 response in BALB/c mice

BACKGROUND

In order to understand the immunoregulation in allergic aspergillosis, a murine model was developed by exposing animals to particulate and soluble antigens of Aspergillus fumigatus.

METHODS

BALB/c mice were exposed to soluble Aspergillus antigen intranasally. Animals showing moderate levels of IgE were subsequently exposed to soluble antigen or antigen conjugated to polystyrene beads intranasally. The IgE and IgG1 in the sera and the eosinophils in the blood and lungs were studied. The spleen and lung mononuclear cells were stimulated with both concanavalin A and antigen and evaluated for production of interleukin (IL)-4, IL-5, IL-10, and interferon-gamma.

RESULTS

Animals exposed to particulate antigens showed more elevated serum IgE levels and increased numbers of eosinophils in the blood and lungs than those exposed to soluble antigen. Lung cell cultures from animals exposed to particulate antigens when stimulated with Aspergillus produced IL-4 and IL-5, indicating a TH2 type of response. Animals exposed to soluble antigens showed a weaker TH2 response, as evidence by low IgE levels in sera, fewer eosinophils in the blood, and low levels of cytokine production from lung and spleen cells.

CONCLUSION

The results indicate that the physical nature of the antigen may have a major role in determining the type of immune response of the host.

Hypersensitivity pneumonitis resulting from Aspergillus fumigatus in a greenhouse

A 57-y-old female who had cultivated vegetables in a plastic greenhouse developed a case of hypersensitivity pneumonitis from Aspergillus fumigatus. This report exemplifies a potential hazard caused by a thermotolerant fungus, A. fumigatus, in a poorly constructed greenhouse.

Immunodiagnosis of aspergillosis

Aspergillus species are ubiquitous fungi and have been implicated as the causative agents of a variety of lung disorders in humans. These disorders include allergic, saprophytic, and systemic manifestations. The allergic disorders mainly affect atopic persons, and invasive or systemic diseases affect immunosuppressed individuals. Immunodiagnosis can help the practitioner diagnose these diseases. Demonstration of circulating antibodies is a useful criterion, but the lack of dependable and standardized antigens is a limiting factor in the diagnosis of most Aspergillus-induced diseases. Despite this limitation, however, immunodiffusion and enzyme-linked immunosorbent assays have been widely used for the detection of antibodies in the sera of patients with aspergillosis. Similarly, crude and semipurified antigens are being used to demonstrate skin hypersensitivity in patients, and several methods have been useful in the detection of antigenemia in patients with invasive aspergillosis. With a growing number of reports on the incidence of aspergillosis and an increase in the number of immunosuppressed individuals in the population, more rapid methods and more reliable reagents for immunodiagnosis are needed. With recent attempts at obtaining reliable reagents for through hybridoma technology and molecular biological techniques, substantial progress toward efficient immunodiagnosis may be achieved.