Landscape Plant Selection Criteria for the Allergic Patient.

Patients with pollen-related allergies are concerned about the species within their landscape that provoke their symptoms. Allergists are often asked for guidance but few information sources are available to aid patients in the recognition of allergenic plants and strategies to avoid personal exposure to them. Landscaping and horticultural workers also have few reliable guidance references, and what is available usually extols the virtues of the plants rather than their negative features. The aim of this article was to provide the results of the Landscape Allergen Working Group that was formed by the AAAAI Aerobiology Committee, which aimed to fill these existing knowledge gaps and develop guidance on producing a low-allergenic landscape. Within the context that complete pollen avoidance is unrealistic, the workgroup introduces selection criteria, avoidance strategies, and guidance on low-allergenic plants that could be selected by patients to reduce the overall pollen burden in their landscape environment. Specific focus is placed on entomophilous plants, which require insects as dispersal vectors and generally produce lower quantities of pollen, compared with anemophilous (wind-pollinated) species. Other biological hazards that can be encountered while performing landscaping activities are additionally reviewed and avoidance methods presented with the aim of protecting gardeners, and workers in the landscape and horticulture industries. The guidance presented in this article will ultimately be a helpful resource for the allergist and assist in engaging patients who are seeking to reduce the burden of allergen in their landscape environment.

Home Assessment and Remediation.

Awareness of the relationship of fungi to asthma in indoor air is very old and well documented. There is substantial evidence that mold and dampness exacerbate asthma in sensitized individuals. Many governmental and nongovernmental organizations around the world have issued guidelines to the effect that the elimination of moisture intrusion and the removal of moldy items from living space can improve respiratory health. The process of home assessment for moisture and mold presence is discussed along with factors that can be used to guide fungal exposure reduction efforts. An approach to the assessment process itself is outlined, and common causes of moisture and mold damage are described. Points that should be included in a report resulting from a home assessment and rudimentary elements of report interpretation are discussed. Emphasis is that interpretation of sampling for moisture and fungal presence should be provided by the person performing the assessment. We conclude that multifaceted remediation contributes to fungal allergen avoidance. The use of an indoor environmental professional to generate evaluation reports and remediation activities can be a valuable contribution to an overall allergen avoidance strategy.

Procedures to Assist Health Care Providers to Determine When Home Assessments for Potential Mold Exposure Are Warranted.

Drawing evidence from epidemiology and exposure assessment studies and recommendations from expert practice, we describe a process to guide health care providers helping their patients who present with symptoms that might be associated with living in damp housing. We present the procedures in the form of a guided 2-part interview. The first part has 5 questions that triage the patient toward a more detailed questionnaire that reflects features of housing conditions known to be reliably associated with exposures to mold and dampness contaminants. We chose the questions based on the conditions associated with moisture problems in homes across the United States and Canada. The goal is to facilitate the clinician's effort to help patients reduce exposure to environmental triggers that elicit symptoms to better manage their disease.

Taxonomy of Allergenic Fungi.

The Kingdom Fungi contains diverse eukaryotic organisms including yeasts, molds, mushrooms, bracket fungi, plant rusts, smuts, and puffballs. Fungi have a complex metabolism that differs from animals and plants. They secrete enzymes into their surroundings and absorb the breakdown products of enzyme action. Some of these enzymes are well-known allergens. The phylogenetic relationships among fungi were unclear until recently because classification was based on the sexual state morphology. Fungi lacking an obvious sexual stage were assigned to the artificial, now-obsolete category, "Deuteromycetes" or "Fungi Imperfecti." During the last 20 years, DNA sequencing has resolved 8 fungal phyla, 3 of which contain most genera associated with important aeroallergens: Zygomycota, Ascomycota, and Basidiomycota. Advances in fungal classification have required name changes for some familiar taxa. Because of regulatory constraints, many fungal allergen extracts retain obsolete names. A major benefit from this reorganization is that specific immunoglobulin E (IgE) levels in individuals sensitized to fungi appear to closely match fungal phylogenetic relationships. This close relationship between molecular fungal systematics and IgE sensitization provides an opportunity to systematically look at cross-reactivity and permits representatives from each taxon to serve as a proxy for IgE to the group.

Guide for interpreting reports from inspections/investigations of indoor mold.

Inspections and testing of indoor environments for mold growth increased dramatically in the past decade. Allergists can now be presented copies of reports and laboratory data and asked to provide an interpretation, although allergists are seldom trained to review environmental data. There is no single sampling method that is both specific for mold growth and robust enough to reliably detect mold growth. There is no standard method for these inspections or testing and no widely recognized credential for investigators, and therefore reports also vary in quality, objectives, and thoroughness. Despite these issues, observations from informed inspections coupled with results from qualified analyses of samples that are collected with a useful strategy can usually indicate whether mold growth is present in a building, but the nature of the report should be assessed before any interpretation of the results and data are attempted. This rostrum discusses objectives of inspections, describes qualifications for investigators, outlines the limitations of various sampling methods applicable to mold and to some degree endotoxin, and provides guidance for data interpretation.

Prevalence of IgE reactivities in mold-allergic subjects to commercially available fungal enzymes.

Fungi are important aeroallergens. However, fungal allergen sources of consistent quality for clinical testing are not readily available. Because some allergens have been identified as enzymes, we assessed the prevalence of IgE reactivity to commercially available fungal enzymes. The purpose of this study was to determine IgE antibody reactivity by radioallergosorbent assay (RAST) to commercially available fungal enzymes in mold-allergic individuals. Sera from 20 subjects with symptoms of respiratory allergies and skin test reactivity to 2 or more fungal allergens (4 conidial [imperfecti] fungi and/or 8 basidiomycetes) were selected. Controls were six atopic individuals with neither history of fungal allergy nor skin test reactivity to fungi. Seventeen commercial fungal enzymes were used as antigens to evaluate the subjects' IgE antibody reactivity by RAST. Sera from most fungus-allergic individuals showed substantial IgE antibody reactivity to enzymes; control sera showed little or no reactivity. The mean reactivity to all commercial enzymes of all subjects tested was RAST > or = 3% with only one exception. The most reactive fungal enzymes were invertase (bakers' yeast, Saccharomyces cerevisiae), cellulase (Trichoderma viride), and glucosidase (brewers yeast, S. cerevisiae) with mean binding of 14.6, 9.5, and 8.8%, respectively. Using RAST results with a combination of four enzymes from S. cerevisiae (brewers yeast glucosidase, bakers' yeast maltase, invertase, and invertase V), a sensitivity of 100% was shown for detecting mold-allergic patients. The studies suggest that fungal enzymes may be useful source materials for the identification of fungal allergens and may also provide readily available source materials to produce improved diagnostic and therapeutic reagents.

Managing building-related Aspergillus exposure.

Aspergillus exposure is difficult to avoid. Indoor dust contains spores and thermotolerant molds may colonize damp or water-damaged building materials or components. Dust control should be part of diligent maintenance since disturbing dusts, especially during building renovation, can expose occupants to spores. Colonization of HVAC systems can shed spores into a building and expose occupants. Mold colonization warrants prompt and effective remediation, including removal of the colonization with associated debris and dusts without unduly exposing remediation workers, and while controlling fugitive dusts. Cleaning may suffice for non-porous surfaces, but colonized porous materials typically must be removed. Determining successful remediation can be challenging; the objective is not to sanitize, but a building in a 'normal and typical' state, a state that is often poorly defined. This is even more troublesome for colonized HVAC components and for health care facilities. Practical remediation assessment emphasizes inspection and then environmental monitoring. Air sampling may prove useful after inspection and monitoring, assuming prior consensus on the purposeof sampling and interpretation of results. Thoughtful design, careful construction and renovation, and diligent operation and maintenance of a building are all needed to minimize the exposure of building occupants to mold.

Air- and dustborne mycoflora in houses free of water damage and fungal growth.

Typically, studies on indoor fungal growth in buildings focus on structures with known or suspected water damage, moisture, and/or indoor fungal growth problems. Reference information on types of culturable fungi and total fungal levels are generally not available for buildings without these problems. This study assessed 50 detached single-family homes in metropolitan Atlanta, Ga., to establish a baseline of "normal and typical" types and concentrations of airborne and dustborne fungi in urban homes which were predetermined not to have noteworthy moisture problems or indoor fungal growth. Each home was visually examined, and samples of indoor and outdoor air and of indoor settled dust were taken in winter and summer. The results showed that rankings by prevalence and abundance of the types of airborne and dustborne fungi did not differ from winter to summer, nor did these rankings differ when air samples taken indoors were compared with those taken outdoors. Water indicator fungi were essentially absent from both air and dust samples. The air and dust data sets were also examined specifically for the proportions of colonies from ecological groupings such as leaf surface fungi and soil fungi. In the analysis of dust for culturable fungal colonies, leaf surface fungi constituted a considerable portion (>20%) of the total colonies in at least 85% of the samples. Thus, replicate dust samples with less than 20% of colonies from leaf surface fungi are unlikely to be from buildings free of moisture or mold growth problems.

Assessment of the indoor environment: evaluation of mold growth indoors.

Much attention has been focused on indoor molds; resulting in modest amounts of new research. There is strong evidence of respiratory effects. Although mechanisms are disputed, some of the effect (but not all) is likely to be allergy related. There is some evidence that atopic individuals may be more affected, but many nonatopic individuals also are affected. This area needs more general research and specific research on exposure measures (such as what fungal components should be measured) and on health-effect mechanisms. It is worthwhile to emphasize the practical knowledge that is readily available. Buildings should be designed, built, operated, and occupied so that the buildings stay dry. When this situation does not occur, the environmental and clinical aspects that are observed by competent professionals should both be considered when determining causal relationships.