RESUMO
Objective:To investigate the prevalence and clinical characteristics of Mycoplasma pneumoniae( Mp) genotypes and subtypes in children in Tianjin. Methods:Children with pneumonia admitted to Tianjin Children′s Hospital from December 2017 to December 2019 were selected as the research objects. Bronchoalveolar lavage fluid was collected by fiberoptic bronchoscopy. The positive samples were detected by real-time fluorescent quantitative PCR and Mp culture. PCR-restriction fragment length polymorphism(RFLP) and multiple variable number tandem repeats were used for genotyping. Detailed clinical and laboratory data were collected for all cases. Results:The results of RFLP showed that there were 138 cases (78.9%) of typeⅠand 37 cases (21.1%) of type Ⅱ; 37 cases of type M3-5-6-2, including six subtypes B, G, M, S, V and Y; 138 cases of M4-5-7-2 were detected, including seven subtypes of E, J, P, U, X, Z and a. In M3-5-6-2 type, there were 1 case of P1-Ⅰtype (2.7%), 36 cases of P1-Ⅱtype (97.3%), 137 cases of P1-Ⅰ type (99.2%) and 1 case of P1-Ⅱ type (0.7%) in M4-5-7-2 type. There was no significant difference in genotype distribution among different age groups. There were statistical differences in the distribution of four seasons among the 13 genotypes of B, G, M, S, V, Y and E, J, P, U, X, Z, a. All Mp infected children had symptoms of fever and cough. The hospitalization time, fever duration, high fever (>39℃), cough duration, skin changes, digestive system symptoms and liver function injury rate of P1-Ⅰ/M4-5-7-2 pneumonia children were higher than those of P1-Ⅱ/M3-5-6-2 pneumonia children, but the difference was not statistically significant. The WBC count of P1-Ⅱ/M3-5-6-2 types was higher than that of typeⅠand M4-5-7-2; the LDH of P1-Ⅰ/M4-5-7-2 was higher than that of Ⅱ and M3-5-6-2, with statistical difference. There was no significant difference in the incidence of inflammatory consolidation, atelectasis, pleural thickening and pleural effusion among different genotypes. Conclusions:Mp infection in children with pneumonia in Tianjin is mainly P1-Ⅰ/ M4-5-7-2, and P1-Ⅱ is on the rise. P1-Ⅰ and M4-5-7-2 were associated with fever and severe symptoms.
RESUMO
Objective:To investigate the molecular epidemiological characteristics of norovirus (NoV) in hospitalized children with sporadic acute gastroenteritis in Tianjin in 2019.Methods:Fecal specimens and clinical data were collected from 3 116 hospitalized children with sporadic acute gastroenteritis possibly caused by viral infection in Tianjin Children′ Hospital between January and December, 2019. Real-time quantitative PCR was used to detect NoV. Partial sequences of RNA-dependent RNA polymerase (RdRp) and capsid genes of NoV were amplified by RT-PCR. Sequence alignment and phylogenetic analysis were performed for further analysis.Results:Among the 3 116 specimens, 809 (26.0%) were positive for NoV. There were significant differences in NoV detection rate between different age groups ( P=0.000), and the highest NoV detection rate (31.6%) was observed in the age group of 7-12 months. Moreover, the detection rate of NoV varied with seasons ( P=0.000), and the NoV detection rate was highest in winter (39.0%). Based on the sequence analysis of RdRp and capsid genes, 286 identified NoV strains belonged to six genotypes, which were GⅡ.P12-GⅡ.3, GⅡ.P16-GⅡ.2, GⅡ.P17-GⅡ.17, GⅡ.Pe-GⅡ.2, GⅡ.Pe-GⅡ.3 and GⅡ.Pe-GⅡ.4. The predominant genotype was GⅡ.Pe-GⅡ.4 Sydney 2012 (61.2%), followed by GⅡ.P12-GⅡ.3 (33.6%, 96/286), GⅡ.Pe-GⅡ.3 (2.4%, 7/286), GⅡ.P16-GⅡ.2 (2.1%, 6/286), GⅡ.Pe-GⅡ.2 (0.3%, 1/286) and GⅡ.P17-GⅡ.17 (0.3%, 1/286). Patients carrying the NoV of GⅡ.Pe-GⅡ.4 Sydney 2012 genotype were likely to suffer from vomiting than those positive for NoV of GⅡ.P12-GⅡ.3 genotype. Conclusions:NoV was an important pathogen causing acute gastroenteritis in children. GⅡ.Pe-GⅡ.4 Sydney 2012 and GⅡ.P12-GⅡ.3 were the major genotypes of NoV in hospitalized children with sporadic acute gastroenteritis in Tianjin in 2019.
RESUMO
Objective To discuss the clinical features and risk factors of death in children with severe pneumonia treated with invasive mechanical ventilation.Methods Through a retrospective analysis of children with severe pneumonia treated with invasive mechanical ventilation,who were hospitalized in PICU of Tianjin Children′s Hospital from Jan 2011 to Dec 2014,we analyzed the distribution of age,etiologic characteristics,mechanical ventilation,complications and background diseases.The single factor analysis and multiple factors Logistic regression analysis were performed to evaluate the risk factors of death.Results A total of 214 pediatric patients were included,134 were male,and 80 were female.The case fatality rate was 6.17%,the relevance ratio of pathogenic microorganism was 16.36%.The median age of death group was older than that of the survival group(4 mouths vs 2 mouths,P=0.039).The pediatric patients who were more than 1 year old in death group were more than the survival group(21.43% vs 15.8%,P<0.001).The common complications included dencephalopathy(11.68%) and electrolyte imbalance(8.41%).Anemia,cardiopathy and alloplasia of respiratory system were the top background diseases.The results of Logistic multivariate regression analysis showed that there were significant differences in the age above 1 year old(OR:1.019,95%CI:1.003-1.030,P=0.019),secondary acute respiratory distress syndrome(OR:7.254,95%CI:1.581-33.277,P=0.011) and accompanying cardiopathy(OR:0.47,95%CI:0.273-0.81,P=0.007).Conclusion The risk factors of death in children with severe pneumonia treated with invasive mechanical ventilation are the following:the age above 1 year old,secondary acute respiratory distress syndrome or accompanying cardiopathy.