Quality assessment of clinical practice guidelines for the management of wheezing disorders in children.

BACKGROUND: The quality of available clinical practice guidelines (CPGs) for childhood wheezing disorders have not been systematically evaluated.METHODS: CPGs were systematically evaluated by four independent reviewers using Appraisal of Guidelines Research and Evaluation (AGREE) II instrument and the Reporting Items for Practice Guidelines in HealTHcare (RIGHT) checklist. We calculated the overall agreement among reviewers with the intraclass correlation coefficient (ICC).RESULTS: A total of 35 CPGs published between January 2000 and December 2020 were evaluated. The overall agreement among reviewers was good (ICC 0.85, 95% CI 0.83-0.87). The average CPGs score was 42% (range: 25-79). The mean scores of four domains were low: 37% for Stakeholder Involvement (range: 10-85), 28% for Rigour of Development (range: 42-81), 35% for Applicability (range: 11-73) and 24% for Editorial Independence (range: 0-83). The mean reporting rate of the RIGHT checklist was 31%. The Basic Information domain had the highest reporting rate (65%); the Review and Quality Assurance domain had the lowest rate (3%).CONCLUSIONS: The quality of the CPGs was poor. Greater efforts are needed to improve quality in domains to provide high-quality guidelines that can be used as reliable tools for clinical decision-making.

[Classification of tracheobronchial tuberculosis in 252 children].

Objective: To provide theoretical basis for early diagnosis and accurate bronchoscopic classification of tracheobronchial tuberculosis (TBTB) in children through analyzing the clinical characteristics, bronchoscopic classifications and treatment effect in children with TBTB. Methods: In this respective study, we collected clinical data of patients with TBTB who accepted bronchoscopies in Interventional Pulmonology Department of Beijing Children's Hospital Affiliated to Capital Medical University between January, 2006 and December, 2019. The basic data, including clinical manifestations, imaging features, bronchoscopic characteristics and effects of interventional therapy were analyzed. The results of the study were statistically described and analyzed using SPSS 22.0 statistical software for relevant data. Results: Total 252 children with TBTB were included in this study. The median age was 1.7 years (quartile: 0.8 years, 5.2 years). Analysis of the classification of TBTB showed that the percent of lymph node fistula type was 96.4% (243/252), ulcerative necrosis type 1.2%(3/252), granulation proliferation type 0.4% (1/252), and cicatricial stricture type 0.8% (2/252). In addition, 1.2% (3/252) of the cases showed the same bronchoscopic manifestations as lymph node fistula type, but it was not clear on imaging whether the caseous material in the lumen was caused by lymph node or lung erosion. Therefore, the "bronchial fistula type" was proposed. Conclusions: Lymph node fistula type of TBTB was the common in children. The classification of lymph node fistula mostly depended on imaging evidence, and this may lead to some uncertainty in classifying TBTB in cases with no imaging evidence of enlarged lymph nodes.

[Streptococcus agalactiae sak0192 gene contains direct repeats and spacers that are genetic markers for characterizing the strains].

A new approach to differentiation of the Streptococcus agalactiae strains was suggested. The approach is based on the nucleotide polymorphism of the sak0192 gene containing variable number of 16 bp direct repeats and 44 bp spacer regions in different S. Agalactiae strains. In general, the direct repeats were identical, while the spacers were variable. Overall, the structure of the sak0192 gene of S. Agalactiae was analogous to direct repeat cluster of Mycobacterium tuberculosis and Streptococcus pyogenes. The applicability of the sak0192 gene polymorphism as a novel genetic marker to identification of S. Agalactiae and differentiation of the strains was demonstrated.

Evaluation of the rpoB macroarray assay to detect rifampin resistance in Mycobacterium tuberculosis in Beijing, China.

The aim of this study was to evaluate the modified rifampin oligonucleotide (RIFO) macroarray method to detect mutations in the hot-spot region of the rpoB gene, associated with rifampin (RIF) resistance in Mycobacterium tuberculosis. The study sample included 123 strains of M. tuberculosis isolated in the Beijing, China, area in 2002-2005, including 73 RIF-resistant and 40 pansusceptible strains. The genotypic assay successfully identified 91.8% of the RIF-resistant strains, whereas no mutations were found in RIF-susceptible strains. The most frequently detected rpoB mutations were in the codons 516, 526, and 531, together accounting for 74% of RIF-resistant strains. Spoligotyping subdivided all strains into 11 unique profiles and 3 profiles shared by 3, 4, and 103 strains, respectively. The 113 strains belonged to the Beijing family genotypes, defined by the specific spoligotype signature (absence of signals 1-34) and deletion of the RD105 region. The rpoB S531L (TCG-->TTG) mutation was found in 57.4% of the RIF-resistant strains of the Beijing genotype. A mutation in the rpoB hot-spot region was found in 51 of the 55 (92.7%) multidrug-resistant strains (i.e., resistant to at least RIF and isoniazid), thus demonstrating the added utility of the modified RIFO method to predict multidrug resistance. The RIFO method is relatively simple to perform and allows straightforward interpretation of results; consequently, it can be used in clinical diagnostic laboratories as a fast complement to phenotypic methods.

Adjacent location of the bac gene and two-component regulatory system genes within the putative Streptococcus agalactiae pathogenicity island.

A chromosomal DNA fragment of 8992 bp in size that has not been previously identified in Streptococcus agalactiae, was cloned and sequenced from strain 98-D60C. In particular, this 8992-bp fragment contained genes homologous to the sensor histidine kinase gene and the DNA-binding response-regulator gene of Streptococcus pneumoniae, and S. agalactiae bac gene. Structural and genetic features of the 8992-bp fragment were highly similar to those specific for bacterial pathogenicity islands. Analysis of epidemiologically unrelated S. agalactiae strains revealed that this fragment was present only in bac gene-positive strains. The possible origin of the 8992-bp fragment in S. agalactiae and its significance for molecular mechanisms of "bacteria-host" interactions are discussed.

Clinical diagnosis of group B streptococci by scpB gene based PCR.

BACKGROUND & OBJECTIVES: The goal of the present study was to improve and simplify the diagnosis of Streptococcus agalactiae (group B Streptococcus, GBS) infection for routine clinical practice. METHODS: A total of 71 clinical samples were tested by microbiologic culture, counter immunoelectrophoresis (CIE) and PCR described in the literature. Southern hybridization was accomplished with the Enzo(TM) "DNA Labeling and Detection Kit", Roche (Germany). The computer techniques were used for selection of the specific primers and for analysis of the sizes of PCR products. RESULTS: The primers for the regions around the 51 bp deletion in C5a peptidase gene (scpB) of GBS were selected. PCR analysis revealed the 255 bp amplification fragment in GBS, 306 bp fragment in groups A and G streptococci (GAS, GGS) and did not reveal any fragments in other bacterial species. Among 71 urine and serum clinical samples tested, none were found to be GBS positive by microbiologic culture, 16 samples by CIE, 36 by PCR. The specificity of amplification was confirmed by Southern hybridization. INTERPRETATION & CONCLUSION: The 51 bp deletion in scpB gene in comparison with scpA and scpG genes can be used as a diagnostic tool for identification of GBS. The 51 bp deletion based PCR proved to be faster and more reliable test than microbiologic culture or CIE.

Chromosomal analysis of group B streptococcal clinical strains; bac gene-positive strains are genetically homogenous.

A collection of 45 epidemiologically unrelated Streptococcus agalactiae strains (group B Streptococcus, GBS), belonging to different serotypes, isolated from pregnant women in China and Russia was studied. Strains were characterized by pulsed-field gel electrophoresis (PFGE) employing hybridization with nine genes potentially involved in virulence. Molecular sizes of GBS genomes varied from 2030 to 2290 kb. Location of the genes under study bac, bca, glnA, scpB, cyl, hylB, lmb, scaA and cfb on the GBS genomes was found to be conserved irrelevant to the serotype. Potential virulence genes scpB, hylB, lmb were located on a 91-kb SmaI fragment that is equal to 4.5% of total genome. Ribotyping of the strains under study revealed three different HindIII, nine EcoRI and 12 PvuII ribotypes among 45 strains. A strong correlation between the PvuII ribotype and the presence of the bac gene was observed, with 21 of 22 bac-positive strains belonging to the same PvuII ribotype P1. PFGE patterns of bac-positive strains were also similar. The possibility of close genetic relatedness of all bac-positive strains is discussed.

Abuse of antibiotics in China and its potential interference in determining the etiology of pediatric bacterial diseases.

There is scant information about the etiology and epidemiology of bacterial diseases of infants and children in China because of very little success with bacterial culture. This study describes the severity of abuse of antibiotics among Chinese pediatricians and this abuse's potential interference in determining the etiology of bacterial diseases. According to a survey in Beijing Children's Hospital more than 98% of the patients in the Outpatient Department who were diagnosed with common cold were given antibiotics by physicians. More than one-third of the patients had been taking antibiotics before coming to the hospital. Using a sensitive Staphylococcus aureus assay we found that 70% of blood samples and 43% of cerebrospinal fluid samples from the patients with bacterial meningitis and pneumonia contained antibacterial activity. Bacteria were recovered significantly less often from the samples with antibacterial activity than from those who did not from which antibiotic was not recovered, both in blood (5.3% vs. 12.5%) and in cerebrospinal fluid (2.5% vs. 14.8%). This study indicates that antibiotic abuse is a severe problem in China and that judicious use of antibiotics is urgently needed.