Bilobar atelectasis as clinical presentation of Mycoplasma pneumoniae infection

A wide variety of radiographic findings have been attributed to Mycoplasma pneumoniae infections. To our knowledge, the occurrence of atelectasis involving one or more lobes as a presenting feature of M. pneumoniae infection and requiring fiberoptic bronchoscopy for resolution has never been reported. A 4-year-old girl with a 3 day history of low-grade fever (<38.0°C), and cough was admitted for progressive dyspnea. Mild respiratory distress (SaO2 94%) and reduced vesicular sounds over the lower right lung were found, with slight elevation of white blood cells (13 480 cells/mL; 74% neutrophils) and of C-reactive protein (1.14 mg/dL; normal range, <0.46 mg/dL). Chest X-ray demonstrated right middle and lower lobe atelectasis (Fig. 1a). To detect respiratory pathogens, real-time polymerase chain reaction (PCR) was performed on oropharyngeal swab, which showed a strong positivity only for the P1 cytoadhesin type 1 and 2 gene of the M. pneumoniae genome. Elevated specific serum IgM titers were detected (59 U/mL; normal range, 217 U/mL). The patient was then treated with nebulized glucocorticoids plus albuterol, chlaritromycin and chest physiotherapy. On hospital day 4, the clinical condition, including the mild respiratory distress, and the physical examination were unchanged. Computed tomography (Fig. 1b,c) confirmed the