Type III hypersensitivity reaction in mushroom growers.

Some respiratory symptoms in mushroom growers such as mushroom worker's lung develop by inhalation of certain agents arising from the environment of mushroom cultivation. Recently we observed mushroom workers who had respiratory symptoms which might be type III hypersensitivity reaction to the antigen of Pleurotus floridae. We gave questionnaires to all the mushroom growers at one of the biggest cultivation areas of mushrooms, Pleurotus floridae in Pocheon, Kyunggi Province. Those with respiratory symptoms were subjects for the study. CBC, chest X-ray, pulmonary function test, skin test with Pleurotus floridae extract, and precipitin antibody test to Pleurotus floridae were performed in the study subjects. Out of a total 308 mushroom workers, 23 workers (14 males, 9 females) had respiratory symptoms. Their mean age was 45 years, and their mean duration of engagement was 3.4 years. Their main symptoms were cough (100%), sputum (82.6%), dyspnea (43.5%), and fever with chills (13.0%). Two cases showed increased interstitial lung markings on chest X-ray films. Sixteen cases (73.9%) showed precipitin antibodies against P. floridae extract by counterimmunoelectrophoresis. Antibodies against Micropolyspora faeni and Thermoactinomyces vulgaris were not detected in any subject.