The Study Of Pulmonary Function Changes In Infants With Pneumonia Due To Human Bocavirus Infection

Objective To discuss the pulmonary function changes in infants withcommunity--acquired pneumonia due to human bocavirus(HBoV) or Mycoplasmapneumoniae(MP) infection via tidal breathing,and relatively high viral load or low viralload of HBoV pneumonia clinical features and lung function difference. To study thepathogenic mechanism of HBoV and its influence on lung function, guiding treatment ofdisease and the evaluation of prognosis for providing objective clinical index.Method Applying the real-time fluorescence quantitative PCR method to detectingHBoV-DNA and MP-DAN in the sputum. Test the tidal breath pulmonary function withHBoV positive in64cases(HBoV group),76cases of MP positive infants(MP group) withpneumonia and38cases of normal controls(Jaeger MasterScope).Through aHBoV-DNA≧1×104copies/ml(high viral load group)and HBoV-DNA≧1×104copies/ml(low viral load group).Analyzing the index and tidal breathing flow volume loopsaccording to the etiology(HBoV group and MP group), age (<l age group and1~3yearsold group), viral load of HBoV (high viral load group and low viral load group). Childrenwith pneumonia history of the122HBoV positive cases were retrospectively analyzed,according to the viral load level(high viral load group and low viral load group) forcomparison of clinical features.Result (1)The index responding to small airway function in infant with HBoV,MPpneumonia,(TPTEF/TE, VPTEF/VE, TEF25%and25/PF)were lower than those innormal control group(P<0.05), and reflect the large airway ME/MI had no obviousdifference.In <l age group,infants with RR were higher than normal controlgroup(P<0.05), but PTEF had no significant difference with that of the normal controlgroup. While the HBoV and MP of children infected with RR in1-3years old group are similar to normal control groups, PTEF was lower than that of normal controlgroup(P<0.05).The pulmonary function between groups for different pathogen also had nosignificant difference.The rising limb of TBFVLs in HBoV or MP group became moreclifly and the declined limb became trough-like concave.(2) A high incidence of asthmarelating to high viral load group as compared with low viral load group.During acute phaseof HBoV infection with high or low viral load,wave crest of TBFVLs moves left,and thedeclined limb became trough-like concave, TPTEF, VPTEF, TPTEF/TE, VPTEF/VE,TEF25%,25/PF were significantly decreased as compared with those in healthyinfants.But ME／MI showed no significant difference. Comparison of different viral loadgroup, high viral load group of the TPTEF/TE, VPTEF/VE, TEF25%,25/PF value wassignificantly lower than the low viral load group.Coclusion Lung function impairment is similar due to HBoV and MP infection ininfant with pneumonia, with small airway obstructive as features. In the intuitive TBFVcurve for peak expiratory left shift, descending valleys like depression.The damage type tothe pulmonary function of high viral load group and low viral load group wasconsistent,which performed small airway obstruction. High viral load group is moreobvious than the low viral load group with small airway damage, higher incidence ofclinical symptoms of wheezing. The lung function damage that pathological process andpathological damage of HBoV, after MP infection may have similarities, and the degree ofpathological injury in low viral load group is more serious than that in low viral loadgroup.