Although Mycoplasma pneumoniae ( M. pneumoniae ) infection can cause wheezing in non-asthmatic children, the mechanisms of this symptom remain unclear. Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis and vascular permeability, and is also known to be elevated in cases of chronic pulmonary disease such as asthma. We hypothesized that VEGF may increase in children with acute M. pneumoniae pneumonia and wheezing.

Nine patients with clinical and laboratory evidence of acute M. pneumoniae pneumonia were enlisted from children admitted to Korea University Hospital. They had had more than one episode of wheezing during the illness, which was confirmed by a physician; they comprised the wheezer group. The individuals with M. pneumoniae pneumonia without wheezing were 63 in number, and they comprised the non-wheezer group. Patients with a history of asthma or who had received asthma medications were excluded. Serum concentrations of VEGF, total IgE, eosinophil cationic protein (ECP), and peripheral blood eosinophil counts were measured.

The serum VEGF concentrations were higher in the wheezer group (mean±SD; 650.2±417.9 pg/mL) than in the non-wheezer group (376.5±356.2 pg/mL, P =0.049). M. pneumoniae antibody (1:1,380 vs. 1:596, P =0.048) and serum total IgE (591.8 IU/mL vs. 162.2 IU/mL, P =0.032) were higher in the wheezer group than in the non-wheezer group. There were no differences between the two groups in terms of serum ECP concentration or blood eosinophil count.

In the presence of wheezing, serum VEGF concentrations were higher in the children with M. pneumoniae pneumonia. This finding suggests that VEGF may associate with wheeze-related symptoms in children with acute M. pneumoniae pneumonia.