Objective: To evaluate the clinical and laboratory characteristics of lobar pneumonia infected by M. pneumoniaeand to find more sensitive diagnostic tool in children.
Methods: We analyzed medical records of 78 children, admitted to Chungnam National University Hospital and diagnosed with lobar pneumonia by chest X-rays between March 2010 and December 2011. White blood cells, C-reactive protein (CRP), procalcitonin (PCT), specific antibodies to M. pneuomoniae, and cold agglutinin (CA) were measured at admission. Children were divided into 2 groups: those with M. pneumoniaeinfection (group A) and those without (group B). Group A children were also subdivided into 2 categories: those with increased CA (group A1) and those without (group A2).
Results: M. pneumoniae infection usually occurred in summer and autumn. Group A children accounted for 75.6% (59/78) of all cases. The onset age was higher in group A than in group B (P=0.016). WBC counts and PCT values were higher in group B than in group A (P=0.015 and P=0.011). Radiologic findings showed that the lower lobe was most commonly involved without predilection for either side and that pleural effusion was present in 13.6% of all cases. The duration of fever before admission was longer in group A1 than in group A2 (P=0.019).
Conclusions: The clinical symptoms and signs of lobar pneumonia caused by M. pneumoniae infection were more severe and can be accurately diagnosed using serum PCT values than using CRP values.