Clinical characteristics of pneumonia caused by Mycoplasma pneumoniae in children of different ages

To study clinical characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children of different ages. We investigated the medical records of MPP patients admitted at Children's Hospital of Soochow University from January 2006 and December 2013. The presence of MP was confirmed by real-time PCR and ELISA. There were overall 3358 children with MPP. 412 (12.3%) were < 6 months old. Six months to 1 year, 1-3 years, 3-5 years and >= 5 years old children constituted 423 (12.6%), 1033 (30.8%), 733 (21.8%) and 757 (22.5%) respectively. Fever was less frequent in < 6 months old infants, with frequency increasing in older patients. The proportion of patients with wheeze was highest (57.9%) in patients aged 6 months to 1-year-old. Tachypnea, cyanosis and hypoxemia were more prevalent in < 6 months old infants (P= 0.00). Radiologically, bronchopneumonia was frequent among infants, while segmental/lobar pneumonia was frequent in >= 5 years old patients. White blood cell and platelet counts of infants were significantly higher than other children. Neutrophil count, c-reaction protein levels was significantly different amongst age groups. Our study revealed MPP patients of different ages presented with different clinical findings especially < 6 months old and >= 5 years of age, which may indicate different pathological findings in age groups of patients with MPP.