Objective To summarize the epidemiology and evaluate possible age-related differences in the presenting clinical features in three year-old children with Mycoplasma pneumoniae pneumonia(MPP)during 2009 to 2014.Methods The medical records of 17855 children with community-acquired pneumonia enrolled by Children′s Hospital of Soochow University during 2009 to 2014.Totally 1145 younger than three year-old children with MPP were enrolled,and they were classified into three groups of 1 month to 1 year-old group (n=512),1 to 2 year-old group (n=393) and 2 to 3 year-old group (n=240).The epidemiology and possible age-related differences in the presenting clinical features,main laboratory and imaging results in three year-old children with MPP were summarized.Results (1) The highest infection rate of different reasons in Suzhou was in autumn(10.46%),and the lowest was in spring(6.95%),The highest infection rate of different ages was 2 to 3 year-old group(11.61%),and the difference was statistically significant (P<0.05).(2) Compared with 1 month to 1 year-old group(n=512,4.31%) and 1 to 2 year-old group (n=39,10.09%),2 to 3 year-old group (n=240,11.61%) had higher infection rate,more patients with fever(53.9% vs. 77.1% vs. 85.4%) and high fever(16.8% vs. 30.5% vs. 41.4%),longer time to normalization of temperature(3d vs. 5d vs. 6d),but less patients with wheezing(61.3% vs. 52.4% vs. 42.9%) and dyspnea(7.6% vs. 4.6% vs. 3.8%).(3) The differences were statistically significant in the percentage of neutrophils,lymphocytes,CRP and platelet count between different ages(P<0.001).(4) The incidences of large area of lesions in chest X-ray examination among different ages had significant differences(P<0.001).Conclusions MP is one of the important pathogens of respiratory tract infection in younger than 3 year-old children.It can occur in every season,and the highest infection rate of MP is in autumn and spring.In younger than 3 year-old,older patients are more vulnerable to infection of MP,the number of fever and high fever are more,fever duration is longer,but younger patients are more vulnerable to virus infection and prone to dyspnea.Chest X-ray examination shows small patchy shadow in most cases,the younger children are more easily to have large area of lesions and pleural effusion.

We aimed to find the relationship between the clinical characteristics and mucus plug formation and developed models to predict mucus plug formation in refractory Mycoplasma pneumoniae pneumonia (RMPP) infection. Methods: RMPP patients treated with bronchoscopy were retrospectively enrolled in the study between November 2011 and November 2015. Multivariate logistic regression was performed to identify independent predictors of mucus plug formation. Results: Of the 173 RMPP patients enrolled, the mucus plug group accounted for 82 (47.4%) cases. Multivariate logistic regression analysis identified age, fever duration, C-reactive protein (CRP) and lactic dehydrogenase (LDH) as independent risk factors for mucus plug. We assigned one point for age, length of fever and CRP and two points for LDH. Using this predicted score, we identified patients with mucus plug with 71.8% sensitivity and 78.9% specificity. Conclusions: Our predictive models based on demographic and laboratory variables accurately predicted mucus plug formation in initial treatment of patients with RMPP.

OBJECTIVE:To explore the dynamic changes of airway hyperresponsiveness (AHR) in children with cough variant asthma (CVA).METHODS:A prospective observational study was conducted at the Children's Hospital of Soochow University from April 2012 to March 2013. A total of 36 patients were diagnosed as CVA. According to the integral dose of histamine resulting in a 20% (PD20) fall in forced expiratory volume in 1 s (FEV1), the severity of CVA was graded. Corresponding treatment was administered and the dynamic changes of airway hyperresponsiveness were followed for 0, 1 and 6 months.RESULTS:Among them, 14 patients suffered from CVA only while another 22 cases had CVA plus upper airway cough syndrome (UACS). PD20 of CVA and CVA+UACS groups were (0.46 ± 0.26) and (0.58 ± 0.34) mg respectively. No statistically significance existed between two groups (t = -0.880, P > 0.05). According to the value of PD20, AHR in CVA patients was classified into four degrees of severe, moderate, mild and very mild. Initially there were moderate (n = 8), mild (n = 21) and very mild (n = 5). At 1 month follow-up, moderate (n = 1), mild (n = 28) and borderline (n = 7); At 6 month, moderate (n = 2), mild (n = 20) and very mild (n = 7). And 4 cases turned negative and another 3 cases became lost. Cough symptom score and PD20 showed no significant correlation (r = -0.086, P > 0.05).CONCLUSIONS:AHR in CVA patients is predominantly mild and very mild. And it decreases rapidly mostly during initial treatment phase. The proportion of conversion from CVA into negative and typical bronchial asthma is relatively low.

Objective To analyze the changes of lymphocyte subsets in children with acute respiratory syncytial virus lower respiratory tract infection. Methods Multi-pathogen detection using direct fluorescence antibody test(DFA), clear etiology diagnosis. Lymphocyte subsets in peripheral blood in part of patients(<6 months) were examined by flow cytometry. Results The amount of CD3+ and CD3+CD8+T lymphocyte of RSV patients in the eruption stage was signiifcantly lower than those in healthy controls(P<0.05). The amount of CD3-CD19+, CD19+CD23+, CD4+/CD8+and CD3+CD25+T lymphocyte of RSV patients in eruption stage was significantly larger than that of healthy controls(P<0.05). The amount of CD3+CD4+ and CD16+CD56+T lymphocyte was not significantly different between RSA patients and healthy controls(P>0.05). Conclusion Cellular immunity function is in disorder in children with acute respiratory syncytial virus lower respiratory tract infection. T lymphocytes are extensively depressed early in the course;B lymphocytes are involved in the virus clearance;NK cells have no signiifcant change with those critical cases.

Objective To analyse the virus pathogens that caused children hospitalized with acute respiratory infection in Suzhou from Dec,2005 to Nov,2006.Methods Patients,suffering from acute respiratory tract infec-tion who were admitted to the Children’s Hospital,Affliated to Suzhou University from december 2005 to november 2006 were chosen.The 7 common respiratory viruses,including respiratory syncitial virus(RSV),adenovirus,influnenza A and B,and Parainfluenza 1,2,3,were detected by using direct immunofluenscene viral antigen rapid diagnosis in nasopharygeal aspirate(NPS) of these children.Result Among the all 1,456 samples,546(37.5%) was shown to be viral positive. Of the 1,456 samples ,RSV accounted for 457(83.7%),ADV 32(5.9%),InfA 31(5.7%),InfB 14 (2.6%),PinfⅠ 10(1.8%),PinfⅡ3(0.5%),PinfⅢ 1(0.2%).The peak season of RSV infection was between No-vember and February.Most of infection cases were less than 2 years old.The ratio of male of female was 1.70:1. Conclusion RSV infection is dominant in ARI in Suzhou.