Effect Of Azithromycin Administration Time On The Effectiveness Of Mycoplasma Pneumoniae Pneumonia

Background and purpose:Mycoplasma pneumoniae infection is a major cause of community-acquired pneumonia in children.Azithromycin is always the first choice with better tolerance and compliance.Here,we performed a retrospective study to evaluate the effect of different timing of utilizing azithromycin on the outcome of children with Mycoplasma pneumoniae pneumonia.Method:A total of 623 patients were enrolled in the study and divided into 2 groups according to different timing of utilizing azithromycin therapy.Children received azithromycin within 3 days(72 hours)were classified into the early azithromycin-treated group(n=174),whereas the late azithromycin-treated group(n=449)were consisted of those children treated with azithromycin over 3 days(72 hour)after the onset of Mycoplasma pneumoniae pneumonia.In order to eliminate the interference of the glucocorticoid administration and the bronchoscopy,enrolled patients were divided into 4 subgroups according to whether they were treated with glucocorticoid and bronchoscopy:subgroup A(without glucocorticoid and bronchoscopy),subgroup B(with glucocorticoid and without bronchoscopy),subgroup C(without glucocorticoid and with bronchoscopy),subgroup D(with glucocorticoid and bronchoscopy).We evaluated clinical prognosis depend on demographic,clinical and laboratory characteristics.Results:1.Effect of azithromycin use time on fever duration:Though early azithromycin-treated group has a longer fever duration after azithromycin administration(7.17±4.12 vs 4.82±3.99 days,t=6.352,p<0.01),the whole duration of fever showed no significant difference between early azithromycin-treated group and late azithromycin-treated group(9.02±4.58 vs 9.57±4.91 days,t=1.251,p=0.212).2.Effect of azithromycin use time on recovery of inflammatory indices:The WBC count recovery time in late azithromycin-treated group was significantly less than the early azithromycin-treated group(7.55±5.36 vs 11.36±4.63 days,t=2.532,p=0.014),but the total recovery time of WBC count showed no significant difference between them(14.32±5.32 vs 14.31 ±4.17 days,t=0.004,p=0.997).Though the CRP recovery time in late azithromycin-treated group was also significantly less than early azithromycin-treated group(8.97±5.19 vs 12.09±5.46 days,t=4.143,p<0.001),the total recovered time showed no significant difference between them(15.25±4.85 vs 14.75±5.23 days,t=0.686,p=0.494).3.Effect of azithromycin use time on intrapulmonary complications:There was no significant difference between early azithromycin-treated group and late azithromycin-treated group in the rate of pulmonary atelectasis(17.82%vs 15.59%,χ2=0.457,p=0.449)or pleural effusion(19.54%vs 23.39%,χ2=1.070,p=0.301).Until one month after azithromycin therapy,the rate of atelectasis resolution(22.58%vs 35.71%)or pleural effusion disappearance(58.82%vs 57.14%)in two groups also showed no significant difference(χ2＝1.712,p=0.191;χ2=0.073,p=0.788).4.Effect of azithromycin use time on extrapulmonary complications:There was no significant difference between the early azithromycin-treated group and the late azithromycin-treated group in the rate of extra-pulmonary complications,including myocardial damage(13.79%vs 17.37%,χ2=1.173,p=0.279),liver function abnormalities(5.17%vs 9.35%,χ2=2.918,p=0.088),rash(1.72%vs 4.01%,χ2=2.007,p=0.157),hypopotassaemia(4.0%vs 1.78%,χ2＝11.812,p=0.178).5.Effect of azithromycin use time on special treatment need:No significant difference was found in the special treatment need between the early azithromycin-treated group and the late azithromycin-treated group,including bronchoscopy(27.01%vs 35.19%,χ2=3.799,p=0.051),glucocorticoid(7.47%vs 4.90%,χ2=1.564,p=0.211),both bronchoscopy and glucocorticoid(8.62%vs 8.91%,x2=0.013,p=0.909).6.Effect of azithromycin use time on development of severe or refractory Mycoplasma pneumoniae pneumonia:There was no significant differences between early azithromycin-treated group and late azithromycin-treated group in the development of refractory Mycoplasma pneumoniae pneumonia(36.21%vs 29.84%,χ2=2.348,P=0.125)or severe Mycoplasma pneumoniae pneumonia(10.92%vs 8.91%,χ2=0.591,p=0.442).Conclusion:The early or the late azithromycin treatment is not associated with clinical prognosis of Mycoplasma pneumoniae pneumonia in children.