Antibiotic resistance of Streptococcus pneumoniae in Vietnamese children with severe pneumonia: a cross-sectional study.

Background: Streptococcus pneumoniae is the most common bacterium that causes community-acquired pneumonia (CAP) in children. The rate of S. pneumoniae resistance to antibiotics is increasing, particularly in patients with severe CAP. Therefore, the level of antibiotic resistance of S. pneumoniae causing severe CAP in Vietnamese children requires regular monitoring. Methods: This was a cross-sectional descriptive study. Nasopharyngeal aspiration specimens from children were cultured, isolated, and examined for S. pneumoniae. Bacterial strains were assessed for antimicrobial susceptibility, and the minimum inhibitory concentration (MIC) was determined. Results: Eighty-nine strains of S. pneumoniae were isolated from 239 children with severe CAP. The majority of isolates were completely non-susceptible to penicillin (1.1% intermediate, 98.9% resistant) and highly resistant to erythromycin (96.6%) and clarithromycin (88.8%); the rate of resistance to ceftriaxone was 16.9%, with the proportion of intermediate resistance at 46.0%; 100% of strains were susceptible to vancomycin and linezolid. For most antibiotics, MIC50 and MIC90 were equal to the resistance threshold according to the Clinical and Laboratory Standards Institute 2021; penicillin had an eight-fold increase in MIC90 (64 mg/L) and ceftriaxone had a 1.5-fold increase in MIC90 (6 mg/L). Conclusion: Streptococcus pneumoniae isolates described in this study were resistant to many antibiotics. Penicillin should not be the first-line antibiotic of choice, and ceftriaxone at an enhanced dose should be used instead.

Low-pressure ultraviolet-H2O2 photolysis for restoring the anodic stripping voltammetry signal: a new strategy for the detection of heavy metal ions in complex organic matter.

A new strategy based on low-pressure ultraviolet (LPUV)-H2O2 advanced oxidation photolysis for the quantitative determination of organic heavy metal ions (HMIs) in soil was proposed for the efficient, low-cost, accurate, and green detection of Pb(II) and Cd(II) in soil extracts by breaking the complexation of HMIs and organic matters, consequently restoring the ASV signals of target HMIs. The key parameters of the proposed LPUV-H2O2 photolysis system for the restoration of stripping responses were optimized; the conversion of organic matter to inorganic matter during the photolysis was investigated by total organic carbon (TOC); the degradation kinetics of humic acid sodium (HAS) was measured by UV-vis spectroscopy (UV); the pathway of HAS converted to small molecule organics during degradation was observed by fluorescence spectroscopy (FS); additionally, Fourier transform infrared spectroscopy (FTIR) was used to study the complexation between HAS and HMIs. The results showed that the stripping signals of target HMIs in the simulated soil samples can be restored to nearly 100% with a good repeatability, and the restoration ratio of the stripping signal fluctuated within 10%. And the feasibility of the proposed method for the accurate detection of HMIs in the real soil samples was verified; the results showed that 93.7% of Cd(II) and 92.5% of Pb(II) in real soil extracts were detectable.

Responsiveness of Inhaled Corticosteroid Treatment in Children with Asthma: The Role of rs242941 Polymorphism of CRHR1 Gene.

INTRODUCTION: Inhaled corticosteroid (ICS) is the most widely used and effective treatment of asthma. However, some patients do not respond to ICS, which might be due to various genetic factors. Hence, understanding the genetic factors involved in the ICS response could help physicians to individualize their treatment decision and action plans for given patients. This study aimed to analyze the characteristics of corticotropin-releasing hormone receptor 1 (CRHR1) genotypes in children with asthma and the correlation between rs242941 polymorphism of CRHR1 gene and ICS responsiveness. METHODS: This prospective study included children with uncontrolled asthma, assessing their eosinophil count, IgE concentration, lung function, and fractional concentration of nitric oxide in exhaled breath (FENO) and performing CRHR1 polymorphism sequencing. The level of asthma control was assessed by asthma control test (ACT); the responsiveness of asthma treatment with ICS was evaluated by measuring the change of ACT and forced expiratory volume in 1 s (FEV1) after treatment versus at inclusion. RESULTS: In total, 107 patients were analyzed for CRHR1 at rs242941. Among these, 86 (80.3%) had homozygous wild-type GG, 20 (18.7%) had heterozygous GT genotypes, and 1 (1.0%) had a homozygous variant for TT. Children with personal and family history of atopy were more likely to have GT and TT genotypes. The severity of asthma was similar between children with asthma in the three groups of GG, GT, and TT genotypes of CRHR1 at rs242941. FENO level, total IgE concentration, and eosinophilic count in children with asthma were not significantly different between GG and GT genotypes. The patient with a TT homozygous variant genotype had a higher level of FENO. There was no correlation between CRHR1 polymorphism at rs242941 and asthma control evaluated by asthma control test and lung function parameters. CONCLUSION: TT genotype of rs242941 in the CRHR1 gene is not frequent. Clinical and functional characteristics of children with asthma with rs242941 polymorphism of CRHR1 gene remain homogeneously similar. There is no correlation between rs242941 polymorphism and ACT or FEV1.

Study on the co-infection of children with severe community-acquired pneumonia.

BACKGROUD: Pneumonia is one of the leading causes of death in children under 5 years old. Viruses have historically been the most common cause of community-acquired pneumonia in children. Co-infections in severe pneumonia are more concern by clinicians. METHOD: It was a perspective and descriptive study. Real-time polymerase chain reaction (RT-PCR) is a modern test that was used to detect many new pathogens, including microbiological co-infections. RT-PCR technique was used in this study to investigate the causes of severe pneumonia. RESULTS: Through the analysis of nasopharyngeal aspiration samples from 95 children with severe community-acquired pneumonia, the positive RT-PCR rate was 90.5%. Viral-bacterial co-infection accounted for the highest proportion (43.1%), followed by bacterial co-infection (33.7%), viral infection (7.4%), bacterial infection (6.3%) and the remaining 9.5% was unknown. In the co-infections groups, the five main bacteria species detected by PCR were Streptococcus pneumoniae, Haemophilus influenzae, MRSA, Moraxella catarrhalis and Mycoplasma pneumoniae. CONCLUSION: Antibiotic treatment should focus on detected microbes in cases of severe pneumonia for having a good result.

Clinical and functional characteristics of OSA in children with comorbid asthma treated by leukotriene receptor antagonist: A descriptive study.

Background: Obstructive sleep apnea (OSA) is the most common form of respiratory disorders during sleep in children, especially those with severe asthma. However, optimal treatment of asthma might significantly improve OSA severity. Methods: It was a cohort study including children aged >5 years old and diagnosed with asthma according to GINA (Global Initiative for Asthma). The data related to age, gender, height, weight, body mass index (BMI), clinical symptoms and medical history of asthma, spirometry (FEV1: forced expiratory in 1 s), and exhaled nitric oxide (FENO) were recorded for analysis. Respiratory polygraphy (RPG) was done for each study subject to diagnose OSA and its severity. Results: Among 139 asthmatic children, 99 patients with OSA (71.2%) were included in the present study (9.3 ± 0.2 years): 58.6% with uncontrolled asthma and 32.3% with partial controlled asthma. The mean ACT (asthma control testing) score was 19.0 ± 3.4. The most frequent night-time symptoms were restless sleep (76.8%), snoring (61.6%), sweating (52.5%), and trouble breathing during sleep (48.5%). The common daytime symptoms were irritable status (46.5%) and abnormal behavior (30.3%). The mean AHI (apnea-hypopnea index) was 3.5 ± 4.0 events/h. There was a significant correlation between BMI and snoring index (R = 0.189 and P = 0.027), bronchial and nasal FENO with AHI (R = 0.046 and P < 0.001; R = 0.037 and P < 0.001; respectively). There was no significant correlation between asthma level, FEV1 and AHI. The severity of asthma and respiratory function were improved significantly after 3 months and 6 months of asthma treatment in combination with leukotriene receptor antagonist (LRA) treatment. The symptoms related to OSA were significantly improved after treatment with LRA. The severity of OSA was decreased significantly after 3 months and 6 months of treatment. Conclusion: The treatment of asthmatic children with comorbid OSA by LRA in combination with standard therapy for asthma could improve the control of asthma and the symptoms and severity of OSA.

Study of Clinical Characteristics and Cytokine Profiles of Asthmatic Children with Rhinovirus Infection during Acute Asthma Exacerbation at National Hospital of Pediatrics.

Background: In children with asthma, the viral infection of airways is usually a main cause of acute asthma exacerbation and hospitalization. However, few studies on clinical and biomolecular characteristics of asthmatic children in this field have been done, especially in emergent countries. Objective: This study described the clinical and biological characteristics of asthmatic children who had acute asthma exacerbation and rhinovirus (RV) infection. Methods: Children under 15 years of age hospitalized for acute asthma exacerbation were included. They underwent clinical examination and peripheral blood analyses for the cytokine profile. The severity of acute asthma exacerbation was evaluated by Pediatric Asthma Score (PAS). Healthy children under 15 years of age were also invited in this study. Results: One hundred fifteen asthmatic children were included in this study. There were 18.2% of mild PAS, 37.4% of moderate PAS, and 44.4% of severe PSA. Among them, 63/115 (54.8%) asthmatic children had positive RV infection (RV+). The percentages of asthmatic children with RV+ had increased polymorphonuclear leucocytes were significantly higher than asthmatic children with RV-. There were no significant differences of the concentrations of non-Th2-related cytokines in asthmatic children with RV- and RV+. The concentration of Th2-related cytokines (IL-5 and IL-13) in asthmatic children with RV+ was significantly higher than those with RV-. However, there was no significant difference for the cytokine profile between mild, moderate, and severe asthma. Conclusion: RV infection is a main cause of acute asthma exacerbation in children with asthma. The increase of Th2-related cytokines, especially IL-5 and IL-13, is a relevant biomarker for RV infection in asthmatic children with severe exacerbation.

Study of the clinical and functional characteristics of asthmatic children with obstructive sleep apnea.

BACKGROUND AND OBJECTIVE: The obstructive sleep apnea (OSA) is a common respiratory disorder in children, especially those at preschool and school ages. This study aimed to describe the characteristics of asthmatic children with OSA and the symptoms for a high risk of OSA. SUBJECTS AND METHODS: It was a prospective and descriptive study. The data of asthmatic children including medical history, clinical examination, blood tests, spirometry, exhaled nitric oxide (NO), and respiratory polygraphy were registered for analyses. RESULTS: Eighty-five asthmatic children with a mean age of 9.5 ± 2.1 years were included. The prevalence of OSA was 65.9% (56/85) in study subjects. The prevalence of severe OSA in children with moderate asthma was significantly higher than intermittent and mild asthma. The percentage of asthmatic children with OSA who had snoring, sleep disturbance, and nocturnal sweats was significantly higher than that of asthmatic children without OSA (48.2% vs 17.2%, 71.4% vs 27.5%, and 55.1% vs 31.0%, respectively). The presence of allergic rhinitis and snoring was associated significantly with a high probability for the presence of OSA. CONCLUSION: Children with asthma have a risk of OSA. Asthmatic children with suggested symptoms such as snoring or waking up at night should be screened for OSA.

Clinical characteristics and cytokine changes in children with pneumonia requiring mechanical ventilation.

Objective To assess clinical characteristics and cytokine levels in children with severe pneumonia who required ventilatory support. Methods In this prospective, descriptive, cross-sectional study, blood and endotracheal fluid samples were obtained from patients with severe pneumonia, aged <5 years, within 24 h following intubation. Blood samples were also obtained from age-matched healthy controls. Cytokine levels were investigated using flow cytometry-assisted immunoassay. Results Forty-five patients with severe pneumonia requiring mechanical ventilation (aged 10 ± 5 months) and 35 healthy age-matched controls were included. Patients with severe pneumonia had significantly increased serum interleukin (IL)-6, IL-8, and granulocyte/macrophage colony-stimulating factor concentrations compared with controls (80.84 pg/ml versus 2.06 pg/ml, 90.03 pg/ml versus 6.62 pg/ml, and 115.58 pg/ml versus 11.47 pg/ml, respectively). In the severe pneumonia group, serum IL-10 levels were significantly higher in patients aged <6 months versus those aged 6-12 months. Age-group differences in serum cytokine levels did not correspond to age-group differences in endotracheal-fluid cytokine levels. Serum IL-6 levels were significantly higher in patients who subsequently died versus those who survived (267.12 pg/ml versus 20.75 pg/ml, respectively). Conclusion High IL-6 concentrations were associated with mortality in patients <5 years of age with severe pneumonia requiring mechanical ventilation.

The profile of leucocytes, CD3+, CD4+, and CD8+ T cells, and cytokine concentrations in peripheral blood of children with acute asthma exacerbation.

Objective To determine the leucocyte profile and cytokine concentrations in the peripheral blood of children with an acute asthma exacerbation (AAE). Methods This descriptive, cross-sectional study enrolled paediatric patients admitted to hospital for AAE. The severity of AAE was assessed using the paediatric asthma score (PAS). Peripheral blood samples were collected for automatic quantification of white blood cell counts, CD3+, CD4+, and CD8+ T cells populations by flow cytometry and cytokine concentrations by flow cytometry-assisted immunoassay. Results A total of 127 children with AAE and 30 healthy control subjects were included in the study. The proportion of paediatric patients with decreased CD3+, CD4+ and CD8+ T cells was significantly higher in those with severe AAE compared with those with mild-to-moderate AAE. The concentrations of interleukin (IL)-2, IL-8, IL-12, and IL-4 in paediatric patients with rhinovirus infection were significantly higher than in those without rhinovirus infection. IL-2, IL-4, IL-6, TNF-α and GM-CSF concentrations during AAE were significantly lower than control. IL-5 and IL-13 concentrations during AAE were significantly higher than control. Conclusions The decrease of CD3+, CD4+, CD8+ T cells and IL-2, IL-4, IL-6, TNF-α, and GM-CSF combined with the increase of IL-5 and IL-13, were associated with AAE in children with asthma.