Molecular epidemiology of norovirus in children with acute gastroenteritis in Tianjin, China / 中国当代儿科杂志

OBJECTIVE@#To investigate the molecular epidemiological characteristics of norovirus (NoV) among children with acute gastroenteritis in Tianjin in 2017.@*METHODS@#A total of 758 stool specimens were collected from the children with acute gastroenteritis possibly caused by viral infection in Tianjin Children's Hospital between January and December, 2017. Quantitative real-time RT-PCR was used for primary screening of NoV, and conventional RT-PCR was used for gene amplification, sequencing and genotype identification of the VP1 region of capsid protein in positive specimens.@*RESULTS@#Among the 758 specimens, 241 (31.8%) were found to have GII NoV. Sequencing of the VP1 region of capsid protein in positive specimens showed that among the 241 specimens with GII NoV, 69 (28.6%) had GII.4 subtype, 51 (21.2%) had GII.3 subtype, 24 (10.0%) had GII.2 subtype, and 18 (7.5%) had other subtypes. There was a significant difference in NoV detection rate between different age groups (P=0.018), and the 1- <4 years group had the highest NoV detection rate (37.3%). There was also a significant difference in NoV detection rate across seasons (P<0.001), and there was a highest NoV detection rate in winter (48.1%). Twenty-seven children (3.6%) had co-infections with NoV and rotavirus.@*CONCLUSIONS@#NoV is one of the major pathogens of the children with acute gastroenteritis from Tianjin in 2017. GII genotype, especially GII.4 subtype, is the prevalent strain. NoV infection is commonly seen in children less than 4 years and reaches the peak in winter. Some children are found to have co-infections with rotavirus.

The study on cytokines of bronchoalveolar lavage fluid in children with mycoplasma pneumoniae pneumonia / 天津医药

Objective To study the cytokine levels of TNF-α, IFN-γ, IL-2, IL-4, IL-6 and IL-10 in bronchoalveolar lavage fluid (BALF) in children with mycoplasma pneumoniae pneumonia (MPP). Methods Clinical data of 90 patients with MPP (MPP group), who were admitted to Tianjin Children's Hospital from January to December 2017, were collected in this study. The 90 cases were divided into group A1 (<7 days), group A2 (7-14 d) and group A3 (15-30 d) according to the course of disease on admission, with 30 cases in each group. Children who were without MPP and needed bronchoscopy examination or treatment at the same time were used as the control group (B group). The expression levels of cytokines (TNF-α, IFN-γ, IL-2, IL-4, IL-6 and IL-10) were detected by enzyme-linked immunoassay (ELISA). Results The serum and BALF levels of TNF-α, IFN-γ, IL-2, IL-4, IL-6 and IL-10 increased significantly in A group compared with those in B group (P<0.05). The highest levels of cytokines (TNF-α, IFN-γ and IL-2) were found in Group A1. The highest levels of cytokines (IL-4 and IL-6) were found in Group A2. Conclusion The levels of TNF-α, IFN-γ and IL-2 are increased significantly in the disease course of < 7 days. In the disease course of 7 to 14 days, the IL-4 and IL-6 are elevated significantly. Our data suggest that these cytokines may be involved in the pathogenesis of MPP.

Analysis of clinical characteristics and antimicrobial resistance of carbapenem-resistant Acinetobacter baumannii infections in children / 中华儿科杂志

<p><b>OBJECTIVE</b>This study aimed to summarize the clinical characteristics and antimicrobial resistance of carbapenem-resistant Acinetobacter baumannii (CRAB) infections in children, identify its risk factors and to raise the level of diagnosis and treatment of this disease.</p><p><b>METHOD</b>The data of clinical and antimicrobial susceptibility of 32 cases of CRAB and 64 cases of carbapenem-susceptible Acinetobacter baumannii (CSAB) infections as control seen between January 1, 2004 and December 31, 2010 in Yuying Children's Hospital Affiliated to Wenzhou Medical College were analyzed retrospectively.</p><p><b>RESULT</b>Thirty-two cases of CRAB infections were identified, 21 were male and 11 female. The ages ranged from 1 day to 16 years (median age 43 days) ,among whom 14 (44%) were aged < or = 28 days; 28 cases (88%) were diagnosed as hospital-acquired pneumonia (HAP) and 4 cases (12%) had wound infection. The common primary diseases of the cases were neonatal respiratory distress syndrome (n = 12, 38%), followed by congenital heart disease (n = 5,16%) and open fractures (n = 5,16%). Before the isolation of CRAB, 10 cases (31%) had received major surgery;29 patients (91%) had stayed in ICUs, 26 cases (81%) had received tracheal intubation and mechanical ventilation,the ventilation time was 2 -249 days (median: 12 days). Carbapenem was used in 17 cases (53%) previously, 13 (41%) had received beta-lactam/beta-lactamase inhibitor combinations, 8 (25%) had used 3rd-generation cephalosporins within 2 weeks before the isolation of CRAB. Sixteen cases (50%) were cured, 12 cases (38%) were improved, parents of 1 case(3%) automatically gave up hospitalization without being cured and 3 cases (9%) died. Forty-nine CRAB strains were isolated from the 32 cases, accounting for 10. 4% of AB isolation strains in the same period, in which 40 strains (82%) were isolated from sputum specimens and 9 strains (18%) from open wounds secretions. All 49 strains showed multidrug-resistance (MDR), of which 13 strains (27%) were pandrug-resistant (PDR) to the common antimicrobials. The rates of resistance to ampicillin-sulbactam and cephalosporins were 90% and more than 85%, respectively; while the rates of resistance to cefoperazone-sulbactam were 19%, the lowest among the tested agents. In multivariate analysis, receiving surgery (OR = 8.450), tracheal intubation and mechanical ventilation for more than 10 days (OR = 6.366) and previous use of carbapenems (OR = 7.084) were independent risk factors for CRAB infections.</p><p><b>CONCLUSION</b>Nosocomial infections in children due to CRAB infections mainly cause HAP and open wound infection. Previous surgery, prolonged tracheal intubation and mechanical ventilation for more than 10 days and previous carbapenems therapy within 2 weeks before the isolation of CRAB were independent risk factors for CRAB infections. CRAB showed MDR or even PDR to the common antimicrobials, which made great difficulties in antibiotic choices.</p>