HYPERSENSITIVITY PNEUMONITIS DUE TO AN ULTRASONIC HUMIDIFIER

We describe a woman with hypersensitivity pneumonitis that was related to using a home ultrasonic humidifier. A micronodular infiltrate was seen in her chest radiograph. The inhalation challenge test was perfor med with the humidifier, and she exhibited a positive response. The cu ltures of the humidifier water grew Candida albicans, Rhodotorula spp. , and Aspergillus spp. The test for precipitating antibodies against t he humidifier water gave a positive response, and specific IgG, IgM, a nd IgA antibodies against extracts of A. fumigatus, C. albicans, and R hodotorula spp. were demonstrated in the patient's serum by ELISA. A s trong, dose-dependent inhibition of Rhodotorula IgG-ELISA by humidifie r water was observed, suggesting that Rhodotorula might be the cause o f hypersensitivity pneumonitis in this patient.