Objective  To analyze chest CT imaging characteristics of children with severe Mycoplasma pneumoniae pneumonia (SMPP) in different age groups.

  Methods  The CT imaging data of 124 children with SMPP was retrospectively analyzed, and they were divided into two age groups including < 5 years of age group (n=60) and ≥5 years of age group(n=64). CT imaging features were compared and analyzed.

  Results  In the 124 cases, the lesions were located in the right side in 72 cases (58.06%), 32 cases (25.81%) in the bilateral side, and 20 cases(16.13%) in the right side, most of these lesions occurred in the right inferior lobar. The proportion of the lesion site in the left lung in the < 5 years of age group was 26.67%(16/60), which was significantly higher than 6.25%(4/64) of the ≥5 years of age group (P < 0.05). There were no differences in proportions of other lesion (P > 0.05). There was no significant difference in imaging characteristics between < 5 years of age group and ≥5 years of age group (P > 0.05). The imaging of the lesions were featured by large patchy consolidation, and pulmonary necrosis, atelectasis, pleural effusion were presented, but scattered patchy shadows, thickening of bronchial wall and other interstitial changes were rarely seen.

  Conclusion  CT findings show large patchy consolidation in chest examination of SMPP children, but the locations of lesions in children aged below 5 years differ from those aged 5 years and above. Therefore, it is necessary to be familiar with CT imaging characteristics so as to timely diagnose SMPP children and improve their prognosis.