3.2 Etiological distribution in 269 children with PB.
In terms of etiology in the 269 PB children, no clear pathogen was
detected in 6 cases and the positive decteciton rate was 97.8%(
263/269), coinfections were detected in 20.4% ( 55/269). Among single
pathogen infection, MP was the most predominant pathogen (75.1%,
202/269 ), followed by influenza virus (0.7%, 2/269), Candida albicans
(0.7%, 2/269), ADV (0.4%, 1/269) and Streptococcus pneumoniae (0.4%,
1/269). Of these 55 cases with combined infection, coinfection of MP and
Streptococcus pneumoniae was the most, with a infection rate of 8.6%
(23/269) , followed by coinfection of MP and ADV (3.3%, 9/269), MP and
influenza virus (3.3%, 9/269), MP and Staphylococcus (3.0%, 8/269), MP
and Acinetobacter baumannii (1.5%, 4/269), MP and Haemophilus
influenzae(0.7%, 2/269). ( Table 1 )
3.3 Clinical characteristics of PB in children.
The mean age of the subjects was 6.7 ± 2.8 years (range, 9 months-14
years), and the male-to-female ratio was 1.04. The mean duration of
fever and hospitalization was 10.6 ± 3.7 and 9.3 ± 3.2 days,
respectively. All the patients presented with cough and fever, and 62
(23.0%) cases suffered from hypoxemia. Of these 269 patients, 3 (1.1%)
had pulmonary embolism, 15 (5.6%) cases was diagnosed as necrotizing
pneumonia, and 144 (53.5%) had extrapulmonary complications, including
16(5.9%) with leukopenia, 62(23%) with digestive system abnormalities
(nausea, vomiting, elevated transaminase), 24(8.9%) with cardiovascular
system abnormalities (elevated myocardial enzymes, abnormal
electrocardiograph(ECG), pericardial effusion and cardiac thrombosis),
40(14.9%) with rash, 21(7.8%) with toxic encephalopathy, and 27(10%)
with electrolyte disorder.
Among these 269 patients, 144 cases underwent FOB and BAL procedure for
once(the single group) and 125 underwent multiple therapy (the multiple
group). There were no statistically differences between the two groups
in age, sex ratio, incidence of fever. Compared with single group,
children in the multiple group exhibited higher peak body temperature,
longer duration of fever and hospitalization. The total incidence of
extrapulmonary complications was higher in the multiple group,
especially in digestive system, however differences in incidence of
blood system, cardiovascular system, skin, central nervous system and
lectrolyte disorder were not observed. ( Table 2 )
3.4 Laboratory characteristics of PB in children.
Laboratory indicators were summarized in Table 3. Higher levels of ESR,
CRP, PCT, IL-6, LA, LDH, FER and D-dimer were observed in PB patients.
The levels of N%, CRP, IL-6, LA, ALT, AST, LDH, FER, D-dimer in
multiple group were higher than those in the single group, and the
differences were statistically significant ( all, P <0.05 ). (
Table 3)