Three previously healthy patients presented with bilateral pulmonary infiltrates, hypoxemia, and respiratory failure associated with Mycoplasma pneumoniae infection. None had underlying pulmonary or immune deficiency diseases. One died with dense fibrotic reorganization of the lungs, and another survived after prolonged mechanical ventilatory assistance. Two developed pulmonary superinfections with Pseudomonas aeruginosa. All had extrapulmonary complications: one had Coombs‘-positive hemolytic anemia, another myocarditis, and all three had abnormal results of liver function tests, consistent with hepatocellular dysfunction.