3.2 Radiological and laboratory findings
The chest CT results of all involved children were obtained on
admission, and 130 (71.4%) had abnormal images, of which 57 (43.8%)
appeared in both lungs, and the rest (56.2%) in unilateral lung. The
common signs of pneumonia in chest CT scans were ground-glass opacities
(GGO) and local patchy shadowing (Figure 2), with the incidence of
28.0% and 27.5%, respectively, whereas the pulmonary consolidation was
much less (1.6%). It was worth noting that there were also 52 (28.6%)
infected children without any changes in chest CT images. Thus, the
concurrence of normal chest CT scan and no symptom contributed to 24
cases of asymptomatic infection, in the ratio of 13.2% (Table 1).
The median values of laboratory results were mostly within normal
ranges, and the details were listed in Table 3 and 4. The rates of
decreased count and percentage of lymphocytes were 3.9% and 34.6%,
respectively; those of eosinophils were 29.5% and 18.8%, respectively.
Other findings in differential of white blood cells included increased
and decreased neutrophil percentage (27.4% and 24.0%), and increased
monocyte percentage (33.3%). Although the levels of PCT and CK-MB
elevated in almost the half (both 47.5%), they changed slightly and had
no clinical significance. The majority (33/39, 84.6%) of identified
possible co-infected pathogen was mycoplasma pneumoniae (MP), and the
other tested pathogens were much less identified. With a further
analysis of the subgroup of possible co-infection with MP, GGO in chest
CT images was less found (21.1% vs 31.5%, p = 0.025), azithromycin was
more used (12.1% vs 1.3%, p = 0.01), and decreased monocytes count was
more common (26.1% vs 5.2%, p = 0.005). Possible MP co-infection had
no influence on serum levels of inflammatory indicators, such as CRP,
PCT and D-dimer. In addition, there was no difference in the prevalence
of allergic diseases between children possibly co-infected with MP or
not (Table S1 and S2).