HYPERSENSITIVITY PNEUMONITIS SECONDARY TO KLEBSIELLA-OXYTOCA - A NEW CAUSE OF HUMIDIFIER LUNG

A 30-year-old woman developed recurrent episodes of fever, dyspnea, an d nonproductive cough after repeated exposure to a home humidifier. Th e diagnosis of hypersensitivity pneumonitis was confirmed by detection of serum-binding antibodies at significant titer to Klebsiella oxytoc a colonizing the humidifier water but not to other potential antigens. This represents a newly recognized cause of hypersensitivity pneumoni tis related to exposure to K oxytoca contaminating a commercially avai lable ultrasonic cold air home humidifier. The potential role for thes e frequently used home humidifier devices in unexplained pulmonary ill ness is emphasized.