Coprinus comatus (shaggy cap) is a potential source of aeroallergen that may provoke atopic dermatitis.
BACKGROUND
Basidiospores are universal components in the air and established as important causes of respiratory allergies. Recent reports indicate that aeroallergens may aggravate eczematous skin lesions in subjects with atopic dermatitis (AD).


OBJECTIVE
The aim of the study was to investigate whether spores of Coprinus comatus, a species of basidiomycetes, may elicit delayed-type skin reactions in subjects with an atopic predilection, especially dermatitis.


METHODS
Sixty-six study subjects were categorized in groups having AD or respiratory allergy with regard to the skin prick test (SPT) reactivity to C comatus extract. Twenty nonatopic individuals served as control subjects. Atopy patch tests (APTs) were performed with extract of C comatus spore containing tissue at a concentration of 1. 35 mg of protein per gram of petrolatum (Vaseline) and C comatus cap at a concentration of approximately 5 mg of protein per gram of petroleum jelly. APT reactions were evaluated after 48 and 72 hours.


RESULTS
Of the subjects with AD completing the study, 12 (32%) of 38 showed a positive APT reaction, with 8 (57%) also having a positive SPT response to C comatus. Only 1 (9%) of 11 subjects with asthma had a positive SPT and APT response to C comatus. No positive test reaction was observed in the nonatopic control subjects or in subjects with respiratory allergy and negative SPT responses to C comatus.


CONCLUSIONS
Our results demonstrate that C comatus can induce delayed-type reactions in atopic individuals, particularly in those with AD. Because spores of Coprinus species are ubiquitous, basidiomycetes have to be considered as possible aeroallergens when investigating causes of eczematous skin lesions in AD.
Fischer
B
B
Institute of Immunology and Allergology, University Hospital, Bern, Switzerland.
Yawalkar
N
N
Brander
K A
KA
Pichler
W J
WJ
Helbling
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000009:adverse effects*; D000485:Allergens / Q000276:immunology*; D000818:Animals; D003302:Coprinus / Q000276:immunology*; D003876:Dermatitis, Atopic / Q000276:immunology*; D005260:Female; D006684:HLA-DR Antigens / Q000302:isolation & purification; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008925:Mites / Q000276:immunology; D010328:Patch Tests; D012867:Skin / Q000276:immunology; D013172:Spores, Fungal / Q000276:immunology*
D000393:Air Pollutants; D000485:Allergens; D006684:HLA-DR Antigens