[So-called "wild silk" asthma--an ever current inhalation allergy to silk waste]

From the end of 1979 to June 1985 an inhalative allergy to silk wastes was diagnosed in the allergy station of the Dermatological Clinic of the University of Zurich in 118 patients, 54,2% of whom were women. Usually, bed quilts advertised as filled with "wild silk" were the cause of the sensitization. Occupational exposure to silk materials was found in only 4 cases. Average age at the time of first appearance of symptoms was 30.5 years, and sensitization time from first exposure to appearance of symptoms was 8.5 months. Monovalent sensitization was found in 44.1%. In most cases exposure prophylaxis sufficed to avoid symptoms. "Wild silk", unlike cultivated (mulberry Bombyx mori) silk, is the product of wild silk moths of the genus Antheraea feeding on oak leaves. Silk wastes are a byproduct of silk manufacturing, consisting of short silk threads (e.g. the end or the beginning of the cocoons), and make highly suitable filling material. During further silk processing the allergenic components, especially sericin, are eliminated by boiling off and degummed. For closer identification of the allergen(s), various kinds of raw and cleaned mulberry and wild silk were tested in sensitized patients by skin and RAST tests. The filling content of different bed quilts was investigated by the Swiss Textile Industry Test Institute. None consisted entirely or mainly of wild silk, and all contained a predominant portion of cultivated silk. The aggressive potency of the "wild silk" bed quilts is due to the insufficiently cleaned and degummed mulberry and wild silk wastes. Contamination of the silk wastes by an insect of the genus Anthrenus was also found.(ABSTRACT TRUNCATED AT 250 WORDS)