Outdoor Alternaria and Cladosporium spores and acute asthma.

BACKGROUND: Outdoor Alternaria and Cladosporium spores are ubiquitous. Few studies have assessed their impact on asthma hospitalizations providing conflicting results, mainly focused on vulnerable paediatric populations. We aimed to study the impact of outdoor Alternaria and Cladosporium concentrations on acute hospitalizations in the Capital Region of Denmark. METHODS: This is a bi-directional case-crossover study with 26 years of national registry data at individual level on acute asthma hospitalizations and daily average data on Alternaria and Cladosporium, pollen (Artemisia, Poaceae), maximal temperature, and air pollution. Conditional logistic regression models were applied to assess the associations. Concentration quartiles at lag 0 were used for categorizing the exposure. RESULTS: For lags 0-2, the odds of hospitalization were significantly higher for both Alternaria and Cladosporium at concentration quartile 2-4 compared with quartile 1. When stratified for age and sex, odds of hospitalization at Alternaria quartiles 2-4 were significantly higher in males below 40 years at lag 0-2, and at lag 0 in females (18-30 years), while quartiles 2-4 of Cladosporium concentrations were associated with significantly higher odds in boys (0-17 years) at lag 1-3, males (18-39 years) at lag 0-1, females (18-39 years) at lag 1-2, males (40-64 years) at lag 0-2, females (40-64 years) at lag 0 and 2, in seniors (65+ years) male at lag 1-2 and female at lag 0-1. The effect of Alternaria varied significantly depending on the level of Cladosporium (p < .0001). CONCLUSION: Ambient Alternaria and Cladosporium spores can induce asthma hospitalizations. Males are more susceptible to both genera. Males and females under age 40 years are more susceptible to Alternaria.

Sensitisation to outdoor and indoor fungi in atopic dermatitis patients and the relation to the occurrence of food allergy to peanuts and walnuts.

The aim of this study is the evaluation of the relation between the sensitisation to outdoor and indoor fungi and allergy to peanuts and walnuts in atopic dermatitis patients aged 14 years and older. The complete dermatological and allergological examinations were performed in all included patients; the occurrence of food allergy to peanuts and walnuts was recorded (specific IgE, skin prick test, history of allergic reaction) and the sensitisation to mixture of outdoor fungi and indoor fungi was also examined (skin prick test, specific IgE). The statistical evaluation of the relation between the sensitisation to outdoor and indoor fungi and the occurrence of food allergy to peanuts and walnuts was performed; 329 patients were included in the study, 110 men and 219 women, the average age 26.8 years. The sensitisation to outdoor fungi was recorded in 91 patients (28%), the sensitisation to indoor fungi was recorded in 61 patients (18.5%), the occurrence of food allergy to peanuts was confirmed in 90 (27%) patients and to walnuts in 121 (36.7%) patients. We confirmed, that patients suffering from sensitisation to outdoor fungi suffer significantly more from food allergy to peanuts and walnuts. The significant relation between the sensitisation to indoor fungi and food allergy to peanuts and walnuts was not confirmed.

Associations between outdoor fungal spores and childhood and adolescent asthma hospitalizations.

BACKGROUND: Childhood asthma is a significant public health problem and severe exacerbations can result in diminished quality of life and hospitalization. OBJECTIVE: We sought to examine the contribution of outdoor fungi to childhood and adolescent asthma hospitalizations. METHODS: The Melbourne Air Pollen Children and Adolescent study is a case-crossover study of 644 children and adolescents (aged 2-17 years) hospitalized for asthma. The Melbourne Air Pollen Children and Adolescent study collected individual data on human rhinovirus infection and sensitization to Alternaria and Cladosporium and daily counts of ambient concentrations of fungal spores, pollen, and air pollutants. Conditional logistic regression models were used to assess associations with increases in spore counts while controlling for potential confounding and testing interactions. RESULTS: Exposure to Alternaria (adjusted odds ratio [aOR], 1.07; 95% CI, 1.03-1.11), Leptosphaeria (aOR, 1.05; 95% CI, 1.02-1.07), Coprinus (aOR, 1.04; 95% CI, 1.01-1.07), Drechslera (aOR, 1.03; 95% CI, 1.00-1.05), and total spores (aOR, 1.05; 95% CI, 1.01-1.09) was significantly associated with child asthma hospitalizations independent of human rhinovirus infection. There were significant lagged effects up to 3 days with Alternaria, Leptosphaeria, Cladosporium, Sporormiella, Coprinus, and Drechslera. Some of these associations were significantly greater in participants with Cladosporium sensitization. CONCLUSIONS: Exposures to several outdoor fungal spore taxa, including some not reported in previous research, are associated with the risk of child and adolescent asthma hospitalization, particularly in individuals sensitized to Cladosporium. We need further studies to examine cross-reactivity causing asthma exacerbations. Identifying sensitization to multiple fungal allergens in children with asthma could support the design and implementation of more effective strategies to prevent asthma exacerbations.

The role of outdoor fungi on asthma hospital admissions in children and adolescents: A 5-year time stratified case-crossover analysis.

BACKGROUND: Some fungal spores can trigger asthma exacerbation but knowledge of which outdoor fungal spores contribute to asthma hospitalisation is limited. OBJECTIVES: To examine the role of outdoor fungal spores in child and adolescent asthma hospitalisations. METHODS: We conducted a bi-directional time-stratified case-crossover study of child and adolescent asthma hospitalisations over 5 years. Conditional logistic regression assessed the role of 20 fungi taxa (Same day [L0] and lagged [L1-3]) adjusted for maximum temperature, humidity and grass pollen. Strata specific effects were explored if there was evidence of effect modification by age, sex, air pollutants or grass pollen. Non-linear effects examined with Generalized Additive Models. RESULTS: Of 2098 children hospitalised for asthma, 60% were boys; mean age was 5.5±3.7 years. Fungal spore counts peaked during warm months. Regression models found weak associations with Coprinus [L0,L1: OR=1.03, 1.01-1.06], Periconia [L0: OR=1.03, 1.001-1.07] and Chaetomium [L2: OR=1.08, 1.0-1.2]. Sex appeared to act as an effect modifier with girls having stronger associations with Cladosporium, Coprinus and total fungi. Older adolescent (14-18 years) hospitalisation was significantly associated with Coprinus and Ustilago/smuts. Air pollutants and grass pollen did not appear to act as effect modifiers. Non-linearity was not detected. CONCLUSION: There may be associations between some outdoor fungal spores and asthma hospitalisations. Further research needed to explore whether these findings can be replicated; and examine whether fungal sensitisation and/or human rhinovirus infections are associated with stronger effects. If findings are replicated, then the need to develop predictive models for fungal spore distribution and levels may become more important.

The characteristics of indoor and outdoor fungi and their relation with allergic respiratory diseases in the southern region of Turkey.

Indoor and outdoor fungal exposure has been shown to be associated with the development of allergic respiratory diseases. The aim of the study was to investigate the types and concentrations of airborne fungi inside and outside homes and evaluate the association between fungal levels and allergic diseases in the southern region of Turkey. A total of 61 children admitted with respiratory complaints to the pediatric allergy clinic between September 2007 and November 2008 were included in this study. The air samples were obtained using the Air IDEAL volumetric air sampler longitudinally for 1 year. A comprehensive questionnaire was used for medical history and housing conditions. Skin prick test was performed to determine fungal sensitivity and spirometric indices were employed. The predominant indoor fungal species were Cladosporium (69.3 %), Penicillium (18.9 %), Aspergillus (6.5 %), and Alternaria (3.1 %). A strong correlation between indoor and outdoor fungal levels was detected for the Cladosporium species (p < 0.001, r = 0.72) throughout the year. Living in a detached home (p = 0.036) and the presence of cockroaches (p = 0.005) were associated with total indoor fungal levels. The presence of cockroaches (aOR 3.5; 95 % CI 0.95-13.10, p = 0.059) was also associated with fungal sensitization at the edge of significance. The statistical cutoff values of indoor and outdoor Cladosporium levels to predict symptomatic asthma were found to be >176 CFU/m(3) (p = 0.003, AUC 0.696; sensitivity 65.5 %; specificity 68.7 %) and >327 CFU/m(3) (p = 0.038; AUC 0.713; sensitivity 66.6 %; specificity 76.9 %), respectively. Children with respiratory symptoms are exposed to a considerable level of fungi inside and outside their homes. The prevention of fungal exposure may provide valuable intervention for respiratory diseases.

Association between transported Asian dust and outdoor fungal concentration during winter in a rural area of western Japan.

BACKGROUND: Recently, Asian dust (AD) has become a serious health problem and several studies have clearly proven that AD can aggravate asthma. However, it remains unclear as to which components of AD have a strong effect on the asthma exacerbation caused by AD exposure. Outdoor fungi can increase emergency department visits and hospitalization for asthma exacerbation and can aggravate asthma symptoms. Therefore, this study was aimed at investigating the relationship between AD and outdoor fungi and determining the potential of fungi to cause airborne particulate matter (PM)-related inflammatory responses. METHODS: Airborne PM was collected each day from January 26, 2015 to February 27, 2015. Daily levels of outdoor fungi-associated PM were calculated using a culture-based method. Production of cytokines such as interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α was assessed in THP1 cells stimulated by the collected airborne PM each day. RESULTS: Daily levels of AD particles were assessed using Light Detection and Ranging and did not correlate with outdoor fungi (r = -0.17, P = 0.94). There was also no association between outdoor fungi and the daily production of IL-6 (r = 0.16, P = 0.37), IL-8 (r = 0.19, P = 0.30), or TNF-α induced by collected PM (r = 0.07, P = 0.70). However, the daily levels of AD particles were significantly associated with IL-6 (r = 0.91, P < 0.0001), IL-8 (r = 0.64, P = 0.0004), and TNF-α (r = 0.72, P < 0.0001) production. CONCLUSION: AD did not increase the acute levels of outdoor fungi and outdoor fungi did not affect the cytokine production induced by airborne PM. These results suggest that outdoor fungi do not have any detectable effect on the asthma exacerbation caused by AD exposure.