[Two cases of hypoxemic acute bronchiolitis due to Mycoplasma pneumoniae]

Two males with acute bronchiolitis due to Mycoplasma (M.) pneumoniae, aged 24 and 39 years were reported. They presented prolonged cough and fever in the early stage of the disease. Chest X-rays of those patients showed diffused nodular shadows. Chest CT scan showed diffused nodular shadows and thickning of bronchovascular marking. Blood-gas analysis indicated hypoxemia without abnormal A-aDO2. We diagnosed two patients as M. pneumoniae infection by antibody assays. The Eosinophil cationic protein (ECP) level and IgE level were high. Eosinophilia and endotoxemia were also observed in two patients. We speculated that the allergic reaction and endotoxemia may be related to hypoxemia and the clinical severity of M. pneumoniae infection.