Bacterial distribution and drug resistance in blood samples of children in Jiangxi Region, 2017-2021.

Objective: This study aims to investigate the distribution and drug resistance of bacteria in clinical blood culture specimens from children in Jiangxi province in recent years and to provide a foundation for preventing and treating bloodstream infection diseases in children. Methods: The study involved a statistical analysis of the isolation and drug resistance of bacterial strains obtained from blood culture specimens of children in Jiangxi province between 2017 and 2021. The analysis was performed using the WHONET 5.6 software. Results: A total of 7,977 bacterial strains were isolated from the blood samples of children between 2017 and 2021. Of these, 2,334 strains (29.3%) were identified as Gram-negative bacteria, and 5,643 strains (70.7%) were identified as Gram-positive bacteria. The most commonly isolated pathogens were coagulase-negative Staphylococcus, Escherichia coli, and Staphylococcus aureus. Among the Gram-negative bacteria, Escherichia coli (840 strains, 36.0%), Klebsiella pneumoniae (385 strains), Salmonella (283 strains), Acinetobacter baumannii (137 strains), and Pseudomonas aeruginosa (109 strains) were the most prevalent. Among the Gram-positive bacteria, coagulase-negative Staphylococcus (3,424 strains, 60.7%), Staphylococcus aureus (679 strains), Streptococcus pneumoniae (432 strains), Enterococcus sp. (292 strains), and Streptococcus agalactiae (192 strains) were the most common. Resistance to third-generation cephalosporins (cefotaxime/ceftriaxone) was observed in 45.9% and 56.0% of Escherichia coli and Klebsiella pneumoniae strains, respectively, while resistance to carbapenems was observed in 4.6% and 20.3% of these strains, respectively. Resistance to third-generation cephalosporins (cefotaxime/ceftriaxone) was observed in 15.5% of Salmonella strains, while resistance to imipenem was absent. Carbapenem resistance was observed in 17.1% (20/117) and 13% (14/108) of Acinetobacter baumannii and Pseudomonas aeruginosa strains, respectively. Methicillin-resistant Staphylococcus aureus (MRSA) was detected in 32.7% of the strains, while methicillin-resistant coagulase-negative Staphylococcus was detected in 64.3% of the coagulase-negative Staphylococcus strains. No Staphylococcus bacteria resistant to vancomycin were detected. Four strains of vancomycin-resistant Enterococcus faecium were detected over the 5-year period, and one strain of linezolid-resistant Enterococcus faecalis was detected. Conclusion: Gram-positive cocci were the most commonly isolated clinical pathogens in blood specimens from children in Jiangxi province. The composition of the pathogen species showed a slight change over the years. The detection ratios of pathogens varied with age group and season. Although the isolation rate of common carbapenem-resistant Enterobacter bacteria has decreased, it remains high. It is necessary to monitor the antimicrobial resistance of pathogens causing bloodstream infections in children more closely, and antimicrobial agents should be used with caution.

Re-evaluate the Prognostic Value of Absolute Lymphocyte Count in Pediatric Immune Thrombocytopenia.

To re-evaluate the prognostic value of absolute lymphocyte count (ALC) in pediatric immune thrombocytopenia (ITP) from the perspective of age. A total of 242 ITP pediatric patients, including 141 newly diagnosed ITP (nITP), 89 chronic ITP (cITP), and 12 persistent ITP, were retrospectively reviewed for this study. These patients were divided into 3 groups according to age (group 1, ≤24 m; group 2, 24-72 m; and group 3, >72 m). The ALC detected at admission was significantly different between nITP and cITP patients without considering their age difference (5.22 vs. 3.55×10 9 /L, P <0.001). However, no significant difference was discovered after age stratification (≤24 m: 6.52 vs. 5.34×10 9 /L, P =0.161; 24-72 m: 3.78 vs. 3.63×10 9 /L, P =0.748; > 72 m: 2.53 vs. 2.40×10 9 /L, P =0.748). ROC analysis showed that the prognostic value of ALC in ITP children was limited (area under curve (AUC): ≤24 m, 24-72 m, and >72 m were 0.591, 0.570, and 0.542, respectively). Analysis of covariance showed there was no significant difference in ALC between nITP and cITP when considering age as a covariate ( P =0.131). Instead, the ROC showing that platelet to lymphocyte ratio (PLR) has prognostic value in pediatric ITP independent of age stratification (≤24 m: AUC, 0.688; 24-72 m: AUC, 0.741; >72 m: AUC, 0.680). In conclusion, there was no significant difference of ALC between nITP and cITP patients when stratified by different age groups, and PLR may be an optional prognostic indicator for ITP.

Investigation of the Distribution of Thalassemia in Children in Jiangxi Province, the People's Republic of China.

Thalassemia is one of southern China's most common inherited disorders. Little is known about the genotypes of thalassemia in children in Jiangxi Province, the People's Republic of China (PRC). Two thousand, nine hundred and fifty-two children with suspected thalassemia were recruited from August 2016 to December 2020 at the Jiangxi Provincial Children's Hospital, Nanchang, PRC. Reverse dot-blot hybridization was used to detect α- and ß-thalassemia (α- and ß-thal) genotypes. A rare mutation was detected using gap-polymerase chain reaction (gap-PCR) and gene sequencing. The overall distribution of thalassemia (1534 cases) was 51.96%, and the detection rate of α-thal (616 cases), ß-thal (888 cases) and concurrent α- and ß-thalassemias (30 cases) was 20.86, 30.08, and 1.02%, respectively. A rare α-thal genotype, -α27.6/- -SEA (Southeast Asian), was identified. Seventy-eight cases of severe ß-thal were detected, accounting for 8.78% of the cases, including 56 double heterozygous cases and 22 cases that were homozygous. Both α- and ß-thalassemias are widely distributed in the children of Jiangxi Province. Thalassemia genetic testing is essential to establish a comprehensive thalassemia prevention program and improve public education.

Surveillance of carbapenem-resistant Klebsiella pneumoniae in a paediatric hospital in China revealed the dynamics of carbapenemase and the prevalence of ST2735 K. pneumoniae.

Background. Carbapenem-resistant Klebsiella pneumoniae (CRKP) is increasingly isolated in paediatric wards, posing a severe threat to these vulnerable populations. This study investigated the clinical features, determinants of carbapenem resistance and clonal relatedness among CRKP in our hospital.Hypothesis. The prevalence of carbapenem-resistant K. pneumoniae in paediatric patients differs from the strains isolated from adult patients in carbapenemase and predominant clones.Aim. To investigate the pattern of carbapenemase and the clonal relationships between carbapenem-resistant Klebsiella pneumoniae in a paediatric hospital in Jiangxi Province.Methodology. Forty-five CRKP isolates were consecutively collected from October 2016 to October 2020. Medical records were reviewed to analyse clinical features. Detection of carbapenemase genes was used to determine CRKP resistance mechanisms and clonal relatedness among CRKP was identified through multi-locus sequence typing (MLST).Results. Forty-three (95.6 %) patients developed CRKP infection, and two (4.4 %) were colonized by CRKP in the urinary tract. The overall mortality rate was 13.3 %. In total, 42 (93.3 %) strains were positive for carbapenemase genes, and bla NDM (62.2 %) was the predominant gene. The MLST identified 24 different sequence types (STs) of CRKP, in which ST11 (n=8, 17.8 %) and ST2735 (n=8, 17.8 %) were the most common STs.Conclusion. The pattern of CRKP in paediatric patients reflects evolving changes. The ST2735 K. pneumoniae may present as a dangerous CRKP clone circulating in paediatric patients.

The association between polymorphisms in PITX2 and congenital esophageal atresia susceptibility.

OBJECTIVE: This study aims to investigate and analyze the connection between PITX2 polymorphisms and the susceptibility of congenital esophageal atresia. METHODS: From January 2015 to June 2020, 46 children with congenital esophageal atresia undergoing surgery were recruited for the study and placed in an observation group, and 40 neonates born in pediatrics during the same period were also recruited for the study and placed in a control group. The alleles and distribution frequencies of the polymorphisms of PITX2 gene rs2200733 were analyzed, and the odds ratio (OR) of esophageal atresia caused by the rs2200733 polymorphism were calculated using a logistic analysis. RESULTS: In the observation group, there were 23 patients (50.00%) with the TT genotype of rs2200733, 21 patients with the TC genotype (45.65%), and 2 patients with the CC genotype (4.35%). In the control group, there were 13 patients with the TT genotype (32.50%), 17 patients with the TC genotype (42.50%), and 10 patients with the CC genotype (25.00%), and the differences in the genotypes between the two groups were statistically significant (P<0.05). The frequencies of the T-alleles and C-alleles of rs2200733 in the observation group were 72.83% and 27.17% respectively, while the frequencies of the control group were 53.75% and 46.25% respectively, and the differences in the rs2200733 allele frequencies were statistically significant (P>0.05). Taking the CC genotype as a reference, the neonates with the TC genotype (OR=2.978, 95% CI=1.084~7.952, P=0.042) or the neonates with the TT genotype (OR=4.778, 95% CI=1.208~13.492, P=0.009) had an increased risk of esophageal atresia, of which the TT genotype indicated a higher risk. CONCLUSION: The polymorphic site rs2200733 (T/C) of the PITX2 gene is connected to the incidence of congenital esophageal atresia. The T-allele is a risk factor for congenital esophageal atresia, and compared with the CC genotype, the TT genotype has an increased risk of esophageal atresia.

Pertussis detection in children with cough of any duration.

BACKGROUND: The diagnosis of pertussis in clinical practice continues to be a challenge worldwide as the symptoms are variable. We aimed to determine the prevalence of pertussis in Chinese children irrespective of cough duration and explore the clinical characteristics of children with pertussis with different cough durations. METHODS: This was a prospective study of children 1 month to 11 years of age with different cough durations in one large Chinese hospital. Bilateral deep posterior nasopharyngeal swabs and venepuncture for full blood count, CRP and serology and sputum were obtained when possible for investigation. E-test strips were used for testing the susceptibility of the B.pertussis isolates against erythromycin, azithromycin, sulphamethoxazole/trimethoprim, levofloxacin, amoxicillin and doxycycline. Demographic, clinical and laboratory information on culture and antimicrobial susceptibility testing was collected from children, and analyzed using SAS v.10 (SAS Institute Inc., USA). RESULTS: After exclusions we analyzed 312 children. Ninety-seven (31.1%) children had laboratory evidence of pertussis. When grouped by cough duration, few characteristics were significant between children with and without pertussis. Of the 36 isolates, 72.2% (26/36)could not be inhibited by erythromycin and azithromycin at all. The MIC50 and MIC90 to amoxicillin were 0.75 mg/L and 1 mg/L respectively, sensitive to amoxicillin by the EUCAST points. CONCLUSIONS: The "one-size-fits-all" clinical pertussis case definition is no longer optimal to recognize this disease. A large comprehensive study of children with all types of cough is required to make substantial inroads into increasing both the sensitivity and specificity in pertussis diagnosis, which will have a beneficial impact on public health. Amoxicillin maybe an alternative for children with marolide-resistant B.pertussis infection; however, local sensitivities are required to inform clinical practice.

[Effects of recombinant fusion protein interleukin-18 on expression of immune-inflammatory factors in mice infected with Staphylococcus aureus].

OBJECTIVE: To observe the effects of recombinant fusion protein interleukin (IL)-18 on the expression of immune-inflammatory factors in the mice infected with Staphylococcus aureus (SA), and to investigate the mechanism of action of IL-18 in defense of SA infection in vivo. METHODS: A total of 40 specific pathogen-free female BLAB/c mice were randomly divided into four groups: control, SA infection, immunized, and intervention. A mouse model of SA infection was established by nasal inoculation with SA liquid. The immunized group and the intervention group were intranasally given IL-18 before SA modeling, and then the SA infection group and the intervention group received the nasal inoculation with SA liquid; the control group was treated with phosphate buffered saline instead. The levels of IL-4, interferon (IFN)-γ, tumor necrosis factor (TNF), granulocyte colony-stimulating factor (G-CSF), IgM in the serum and bronchoalveolar lavage fluid (BALF) of mice were measured by enzyme-linked immunosorbent assay. The expression of macrophage inflammatory protein (MIP)-1α mRNA and MIP-2ß mRNA in the lung tissue of mice were determined by real-time fluorescent quantitative PCR. RESULTS: Compared with the control group, the SA infection group and the immunized group had significantly higher levels of IL-4, G-CSF, and IgM in the serum and BALF and expression of MIP-1α mRNA and MIP-2ß mRNA in the lung tissue (P<0.05); the SA infection group had a significantly lower level of IFN-γ and a significantly higher level of TNF in the serum and BALF (P<0.05); the immunized group had a significantly higher level of IFN-γ in the serum and BALF (P<0.05). Compared with the SA infection group, the intervention group had significantly higher levels of IL-4, IFN-γ, G-CSF, and IgM in the serum and BALF and expression of MIP-1α mRNA in the lung tissue. In contrast, the intervention group showed a significantly lower level of TNF in the serum and BALF and expression of MIP-2ß mRNA in the lung tissue (P<0.05). All the above indicators in the intervention group were significantly higher than those in the control group (P<0.05), except the serum level of IFN-γ. CONCLUSIONS: In the mice infected with SA, the recombinant fusion protein IL-18 by mucosal immunity can affect inflammatory factors in the serum and BALF and the expression of MIP-1α mRNA and MIP-2ß mRNA in the lung tissue to promote the anti-infective immune response and enhance the ability to clear pathogens.

[Immunological mechanism of wheezing attack in children with cytomegalovirus infection].

OBJECTIVE: To study the possible immunological mechanism of wheezing attack in children with cytomegalovirus (CMV) infection. METHODS: A total of 25 under-5-year-old children with wheezing following CMV infection were enrolled. The expression of serum regulatory T cells (Treg)/T helper 17 (Th17) cytokines interleukin (IL)-10, IL-6, and IL-17, and peripheral blood lymphocyte subsets were determined. Twenty age-matched healthy children were selected as the control group. RESULTS: The wheezing group had a significantly reduced serum IL-10 level, significantly increased IL-6 and IL-17 levels, significantly reduced levels of natural killer cells, and significantly increased levels of CD8+ T cells and CD19+ B cells, as compared with the control group. CONCLUSIONS: Wheezing children with CMV infection have Treg/Th17 imbalance and cellular immune dysfunction, which may be an important immunological mechanism of the development of wheezing in children after CMV infection.

Ribosomopathies: mechanisms of disease.

Ribosomopathies are diseases caused by alterations in the structure or function of ribosomal components. Progress in our understanding of the role of the ribosome in translational and transcriptional regulation has clarified the mechanisms of the ribosomopathies and the relationship between ribosomal dysfunction and other diseases, especially cancer. This review aims to discuss these topics with updated information.

[Effects of sublingual immunotherapy on serum IL-17 and IL-35 levels in children with allergic rhinitis or asthma].

OBJECTIVE: To study the clinical effect and mechanisms of specific sublingual immunotherapy (SLIT) for the treatment of allergic rhinitis or asthma in children. METHODS: Thirty children suffering from Dermatophagoides farinae-allergic rhinitis or asthma (case group) and 30 healthy children (control group) were enrolled in this study. The case group accepted SLIT between January and December 2011. The ratio of forced expiratory volume in one second (FEV1) and its expected value, the ratio of airway resistance and its expected value, peripheral blood eosinophil (Eos) count and serum levels of IL-17 and IL-35 were measured before treatment and one and two years after treatment. The rhinitis or asthma symptom scores were rated and the level of asthma control was monitored. RESULTS: Serum IL-17 level in the case group was significantly higher than in the control group before treatment and one year after treatment (P<0.01). Furthermore, serum IL-17 level in the case group gradually decreased from before treatment to 1 year to 2 years after treatment (P<0.01). By two years of treatment, there was no significant difference in serum IL-17 level between the case and control groups (P>0.05). The changes of serum IL-35 level after treatment were opposite to serum IL-17 in the case group. The ratio of FEV1 and its expected value gradually increased from before treatment to 1 year to 2 years after treatment (P<0.01) in the case group. In contrast, the change of the ratio of airway resistance and its expected value and Eos count gradually decreased from before treatment to 1 year to 2 years after treatment (P<0.01) in the case group. More patients achieved improved rhinitis or asthma symptom scores two years after treatment than one year after treatment in the case group (P<0.01). SLIT was effective in 85% of children with allergic rhinitis one after treatment vs 100% two years after treatment. Asthma control was observed in 76% of the asthmatic patients one after treatment vs 92% two years after treatment. CONCLUSIONS: SLIT is effective for allergic rhinitis and asthma in children, and the treatment period of two years seems to be superior to one year. The mechanism of action of SLIT for the treatment of allergic rhinitis and asthma may be associated with inhibition of IL-17 expression and promotion of IL-35 expression.

[Clinical analysis of immune function changes in children with bronchial pneumonia].

OBJECTIVE: To investigate changes in serum complement, immunoglobulins and lymphocyte subsets in children with common and severe bronchial pneumonia, and the role of immune function testing in bronchial pneumonia. METHODS: Twenty children with common bronchial pneumonia, 20 with severe bronchial pneumonia and 20 healthy children (as controls) were enrolled in this study. Immunization rate scattering turbidimetry and six-color flow cytometry were used to detect changes in serum levels of IgA, IgG and IgM, complement C3 and C4 and CD3(+), CD4(+), CD8(+), CD16(+), CD56(+) and CD19(+) cells. RESULTS: The IgA levels of children with common and severe pneumonia were significantly lower than in the control group (P<0.05). The IgG level of children with severe pneumonia was significantly lower than in the control group (P<0.05). There were no significant differences in the levels of IgM and complement C3 and C4 between the two pneumonia groups and the control group (P>0.05). Compared with the controls, the children with severe pneumonia showed significantly lower CD4(+) and CD3(+) counts (P<0.05) and a significantly higher CD19(+) count (P<0.05), and the CD16(+) and CD56(+) counts of children with severe pneumonia were significantly lower than in the controls and in children with common pneumonia (P<0.05). There were no differences in CD8(+) count and CD4(+)/CD8(+) ratio between the two pneumonia groups and the control group (P>0.05). CONCLUSIONS: Immune dysfunction exists in children with bronchial pneumonia, especially those with severe pneumonia. Changes in immune function are correlated with the severity of pneumonia. Immune function testing in children with pneumonia has important clinical significance.