Analysis of the role of paroxysmal nocturnal hemoglobinuria clones in acquired aplastic anemia in children / 临床儿科杂志

Objective To analyze the role of paroxysmal nocturnal hemoglobinuria (PNH) clones in children with acquired aplastic anemia (AA). Methods The relationship between the existence of PNH clones and clinical features in children with AA was retrospectively analyzed. The influence of PNH clones on the efficacy of combined immunosuppressive therapy (IST) of anti-thymocyte globuline (ATG) and cyclosporine A (CSA) was also observed. In addition, multiple factor analysis was used to analyze the main factors affecting the efficacy of AA. Results One hundred and forty-eight children with AA were enrolled, including 74 cases (50%) of granulocyte PNH clones positive, 68 cases (45.9%) of monocyte PNH clones positive, and 93 cases (62.8%) of total PNH clones (granulocytes and / or monocytes) positive. In 49 children having both granulocytes and monocytes PNH clones, the clone size of monocytes and granulocytes was 0.7% (0.4%-1.5%) and 0.2% (0.1%-0.7%), respectively, and the difference was significant (P<0.001) and there was a significantly positive correlation between them (r=0.65, P<0.001). According to the different PNH positive clones (monocytes, granulocytes, total), children were divide into three groups. And there were no differences in gender, age, concurrent infection, white blood cell count, hemoglobin concentration, platelet count, neutrophil absolute count, reticulocyte percentage in different PNH clones positive and negative groups (P>0.05). The group with monocytes PNH clones positive had a positive effect on the efficacy of IST (P=0.02). Multiple factor logistic regression analysis showed that the concentrations of hemoglobin and the positive PNH clones of monocytes were the main factors affecting the efficacy (P<0.05). Conclusions The high concentration of hemoglobin and the positive PNH clones of monocytes contribute the better effect of IST in children with AA.

Subgroup analysis of respiratory syncytial virus in nasopharyngeal secretion of children with acute respiratory infection / 临床儿科杂志

Objective To explore the epidemiology of different subgroups of respiratory syncytial virus (RSV) in hospi-talized children with acute respiratory infections in Suzhou. Methods RSV antigen in nasopharyngeal secretions specimens ob-tained from 42 208 hospitalized children with acute respiratory infections from January 2006 to December 2012 were detected using direct immunofluorescence assay. RT-PCR was used to differentiate subgroups A and B of RSV from the positive samples which were randomly selected in the epidemic season of different years. Results RSV infection had a seasonal trend. The peak season of RSV occurred between November and following year’s March and the detection rate of RSV was low between May and September. There was difference in RSV positive rates of peak seasons among different years from 2006 to 2012 (χ2=280.09,P<0.01). In 398 RSV antigen positive samples obtained from peak seasons of different years, 80.15%(319/398) were differentiated as subgroup A and 15.83%(63/398) were subgroup B except 16 samples (4.02%). There was significant difference in distribution of RSV subgroups in peak seasons among different years (P<0.01). Subgroup A of RSV was prevalent in most years. Both subgroup A and B were prevalent in peak season of 2008~2009 with lowest positive rate of RSV. In 2009~2010, subgroup B was prevalent. Conclusions From 2006 to 2012 in Suzhou area, the RSV detection rates in the first four prevalent seasons present an increase trend every other year and then sustain a high prevalence in the following two prevalent seasons. Subgroup A of RSV was the predominant pathogen in hospitalized children with acute respiratory infections.

Surveillance of pathogen distribution and antimicrobial resistance of bacilli among children with otitis media / 临床儿科杂志

Objectives To analyze pathogen distribution and antimicrobial resistance of bacilli among children with otitis media. Methods Pathogenic bacteria was isolated from children with suppurative otitis media. The VITEK32 was used for iden-tification. The bacterial susceptibility testing was done by Kirby-Bauer method. According to CLSI standard the antimicrobial susceptibility was determined. Results From Jan 2010 to Dec 2012, 425 children with suppurative otitis media were examined. 347 strains were isolated, of which the detectable rate was 81.65%. The detectable rate of bacteria and fungus was 93.37%(324/347) and 6.63%(23/347), respectively. Among bacteria, the detectable rate of streptococcus pneumoniae was 40.92%(142/347) and staphylococcus aureus was 33.43%(116/347). The detectable rate of haemophilus influenza was 7.78%(27/347). The preva-lence of streptococcus pneumoniae is high in children aged 1-3years, with detectable rate at 47.09%. There was no statistical dif-ference among different age groups. The prevalence of methicillin-resistant staphylococcus aureus (MRSA) in middle ear secre-tion was 1.11%(5/45), 18.75%(9/48)and 30.43%(7/23)in 2010, 2011 and 2012 respectively, with no statistical difference (χ2=3.86, P=0.145). The prevalence of penicillin-resistant streptococcus pneumoniae (PRSP) in middle ear secretion was 9.26%, 3.92%and 27.03%in 2010, 2011 and 2012 respectively, with statistical difference (χ2=11.47, P=0.003). Conclusions Choosing correct therapy according to the result of middle ear secretion culture and antibiotics sensitive test can increase the recovery rate of otitismedia.

Epidemiological feature of respiratory syncytial virus in hospitalized children in Suzhou / 临床儿科杂志

Objectives To investigate the epidemiological feature of respiratory syncytial virus (RSV) in hospitalized children with acute respiratory infection. Methods A total of 28 871 children with acute respiratory tract infection from Janu-ary 2007 to December 2011 were enrolled in the study. Nasopharyngeal aspirates were obtained from the respiratory tract by aseptic vacuum aspiration. Direct immuno-lfuorescence assay was used to detect RSV antigen. Correlation between RSV posi-tive rate and meteorological data including mean air temperature and total monthly rainfall, etc. was analyzed. Results The peak infection seasons of RSV during 2007-2010 were winter and spring in Suzhou, while in 2011 the infection rate of RSV was increased since July. The positive rates of RSV during winter and spring in 2007-2008, 2008-2009, 2009-2010 and 2010-2011 were 38.57%, 19.86%, 29.73%and 30.79%, respectively, with signiifcant difference (χ2=176.85, P<0.001). From July to September in 2011, the positive rate of RSV was 5.74%, 21.09%and 31.15%, respectively, higher than that of the same period from 2007 to 2010 (χ2=8.06~405.43, all P<0.05). The positive rate of RSV was negatively correlated with mean temperature, volume of rainfall, duration of sunshine and wind velocity (r=-0.799~-0.214, all P<0.05). Only mean temperature had a signiifcant impact on RSV activity by a stepwise multiple regression (P<0.001). Conclusions The date indicated that RSV was still an important etiological agent for acute lower respiratory infection in infants and young children in Suzhou area during winter and spring. The incidence of RSV was associated with the climate in Suzhou.

Detection of minimal residual disease in childhood acute lymphoblastic leukemia by multi-parameter flow cytometry / 中华检验医学杂志

Objective To establish a flow cytometric measurement of detecting minimal residual disease(MRD) according to the leukemia-associated immunophenotypes in children with acute lymphoblastic leukemia(ALL) and to explore the significance of MRD detection in ALL children for a individualized treatment. Methods A variety of four-color fluorescent antibody combinations were used to investigate the children's normal bone marrow. The normal bone marrow pattern at two-parameter plots was established to identify the residual tumor cells, seventy-five bone marrow samples from newly diagnosed ALL children were analyzed with four-color cytometry to determined the optimal combinations which can clearly distinguish the tumor cells from normal cells. The bone marrow samples were monitored with the combination panel in 60 patients at the end of induction therapy and follow-up treatment. Cytomorphology test, PCR amplification of 29 fusion genes as well as IgG and TCR gene rearrangements were performed simultaneously. Results Sixty-nine cases (92.0%) could be identified for effective antibody combinations to monitor MRD by four-color cytometry. Fusion genes or IgG and T cell receptor (TCR) gene rearrangements can be detected in 21 cases (28.0%) to monitor MRD by PCR. No MRD can be detected in 25 bone marrow samples at the end of induction therapy and follow-up treatment. Four-color cytometry could detect as low as 0.021%-4.130% residual leukemia cells. Conclusion MRD can be monitored by flow cytometry which is faster than PCR, and the sensitivity is superior to morphology method.