OBJECTIVES: To investigate the clinical characteristics and drug resistance profile of invasive non-typhoidal Salmonella (NTS) enteritis in children in Chengdu, China, providing a reference for rational drug use and empirical treatment in clinical practice. METHODS: A retrospective analysis was conducted on the clinical data of 130 children with invasive bacterial enteritis due to NTS identified by fecal bacterial culture and the results of drug sensitivity tests for NTS in Chengdu from January 2022 to December 2023. RESULTS: NTS infections were mainly observed from April to September (113 cases, 86.9%), with a peak in August (36 cases, 27.7%). Children aged <36 months accounted for 86.2% (112/130) of all cases, and the main symptoms were diarrhea (130 cases, 100%), fever (123 cases, 94.6%), and hematochezia (112 cases, 86.2%). The 130 NTS isolates exhibited a sensitivity rate of 64.6% to ceftriaxone and 63.8% to cefotaxime, and a sensitivity rate of >90.0% to piperacillin-tazobactam and nitrofurantoin (nitrofurans). The detection rate of multidrug-resistant strains was 48.5% (63/130), and the clinical efficacy of third-generation cephalosporins used in 38 patients (29.2%) was inconsistent with the results of drug sensitivity tests. CONCLUSIONS The peak of invasive NTS enteritis in children aged 0-6 years occurs in August in the Chengdu area, with a relatively high incidence rate in children aged <36 months. The situation of drug resistance is severe for NTS, and piperacillin-tazobactam may be an effective option for treating multidrug-resistant NTS infections in children, while nitrofuran antibiotics might be used to treat such infections.
Humans ; Infant ; Child, Preschool ; Enteritis/microbiology* ; Retrospective Studies ; Male ; Salmonella Infections/microbiology* ; Female ; Child ; Salmonella/drug effects* ; Infant, Newborn ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/therapeutic use*

OBJECTIVES: To investigate the etiological characteristics of bacterial meningitis (BM) in infants aged <90 days. METHODS: A retrospective analysis was conducted on the etiology and outcomes of BM in infants aged <90 days admitted to five collaborating hospitals between January 2007 and December 2021. The overall etiological profile was described, and pathogen distributions were compared across different age groups, regions, and years. The prognosis of BM caused by common pathogens was also evaluated. RESULTS: A total of 197 infants with bacteriologically confirmed BM were included. The most common pathogens were Escherichia coli (E. coli) (72 cases, 36.5%), group B Streptococcus (GBS) (49 cases, 24.9%), and Listeria monocytogenes (LM) (11 cases, 5.6%). The detection rate of E. coli was significantly higher in the neonatal group than in the infant group (40.2% vs 18.2%, P<0.05). E. coli was the predominant pathogen in Beijing (31.7%) and Kunming (54.1%), while GBS and E. coli were equally prevalent in Shenzhen (33.3%). From 2018 to 2021, the detection rates of E. coli were 46.4%, 47.2%, 45.2%, and 36.8%, respectively, whereas those of GBS were 25.0%, 27.8%, 22.6%, and 31.6%. No significant difference was observed in the overall complication rates among BM cases caused by E. coli, GBS, and LM (P>0.05). However, ventriculitis and hydrocephalus were more frequent in LM meningitis than in GBS meningitis (P<0.017). CONCLUSIONS E. coli is the most common pathogen in BM among young infants, particularly neonates. GBS is predominant in Shenzhen, with an increasing trend. LM meningitis accounts for a notable proportion of cases and is associated with poorer outcomes.
Humans ; Meningitis, Bacterial/microbiology* ; Infant ; Retrospective Studies ; Infant, Newborn ; Male ; Female

OBJECTIVES: To investigate the distribution characteristics and correlation of intestinal and pharyngeal microbiota in early neonates. METHODS: Full-term healthy neonates who were born in Shanghai Pudong New Area Maternal and Child Health Hospital from September 2021 to January 2022 and were given mixed feeding were enrolled. The 16S rRNA sequencing technique was used to analyze the stool and pharyngeal swab samples collected on the day of birth and days 5-7 after birth, and the composition and function of intestinal and pharyngeal microbiota were analyzed and compared. RESULTS: The diversity analysis showed that the diversity of pharyngeal microbiota was higher than that of intestinal microbiota in early neonates, but the difference was not statistically significant (P>0.05). On the day of birth, the relative abundance of Proteobacteria in the intestine was significantly higher than that in the pharynx (P<0.05). On days 5-7 after birth, the relative abundance of Actinobacteria and Proteobacteria in the intestine was significantly higher than that in the pharynx (P<0.05), and the relative abundance of Firmicutes in the intestine was significantly lower than that in the pharynx (P<0.05). At the genus level, there was no significant difference in the composition of dominant bacteria between the intestine and the pharynx on the day of birth (P>0.05), while on days 5-7 after birth, there were significant differences in the symbiotic bacteria of Streptococcus, Staphylococcus, Rothia, Bifidobacterium, and Escherichia-Shigella between the intestine and the pharynx (P<0.05). The analysis based on the database of Clusters of Orthologous Groups of proteins showed that pharyngeal microbiota was more concentrated on chromatin structure and dynamics and cytoskeleton, while intestinal microbiota was more abundant in RNA processing and modification, energy production and conversion, amino acid transport and metabolism, carbohydrate transport and metabolism, coenzyme transport and metabolism, and others (P<0.05). The Kyoto Encyclopedia of Genes and Genomes analysis showed that compared with pharyngeal microbiota, intestinal microbiota was more predictive of cell motility, cellular processes and signal transduction, endocrine system, excretory system, immune system, metabolic diseases, nervous system, and transcription parameters (P<0.05). CONCLUSIONS The composition and diversity of intestinal and pharyngeal microbiota of neonates are not significantly different at birth. The microbiota of these two ecological niches begin to differentiate and gradually exhibit distinct functions over time.
Humans ; Infant, Newborn ; Bacteria ; China ; High-Throughput Nucleotide Sequencing ; Intestines ; Microbiota ; Pharynx/microbiology* ; RNA, Ribosomal, 16S/genetics*

Leclercia adecarboxylata is a Gram-negative bacterium belonging to the Enterobacteriaceae family. To our knowledge, this is the first report of a carbapenem-resistant L. adecarboxylata strain isolated from a healthy newborn. The L. adecarboxylata strain isolated in this study carried four plasmids that may serve as reservoirs for antibiotic resistance genes. Plasmids 2 and 4 did not harbor any antimicrobial resistance genes. Plasmid 3 is a novel plasmid containing three resistance genes. The bla _IMP gene harbored in the strain was most similar to bla _IMP-79 at the nucleotide level, with a similarity of 99.4% (737/741). This case highlights the importance of considering L. adecarboxylata as a potential cause of infections in children.
Infant, Newborn ; Child ; Humans ; Female ; Enterobacteriaceae Infections/microbiology* ; Enterobacteriaceae/genetics* ; Anti-Bacterial Agents/therapeutic use* ; Plasmids

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Air Microbiology ; Bacteria/isolation & purification* ; Child ; Child, Preschool ; China/epidemiology* ; DNA, Bacterial/analysis* ; DNA, Ribosomal/analysis* ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Pneumonia, Bacterial/microbiology* ; Risk Assessment/methods* ; Young Adult

Objective: This study aimed to evaluate the epidemiological, clinical and mycological characteristics of invasive candidiasis (IC) in China. Methods: A ten-year retrospective study including 183 IC episodes was conducted in a tertiary hospital in Beijing, China. Results: The overall incidence of IC from 2010-2019 was 0.261 episodes per 1,000 discharges. Candidemia (71.0%) was the major infective pattern; 70.3% of the patients tested positive for Conclusion The incidence of IC has declined in the recent five years.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antifungal Agents/pharmacology* ; Candidiasis, Invasive/microbiology* ; Child ; Child, Preschool ; China/epidemiology* ; Drug Resistance, Fungal ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Retrospective Studies ; Tertiary Care Centers/statistics & numerical data* ; Young Adult

Group B streptococcus (GBS) is one of the severe pathogenic bacteria during the perinatal period, both on pregnant women and newborns. GBS infection may lead to pneumonia, septicemia, meningitis or other severe disease, even death in neonates. Although only 1%-2% infections will develop into GBS disease among the neonates, the etiological mechanism of which is worth researching. This review summarizes the possible factors related to GBS infection or occurrence of the disease, including the risk in gestation period (for example, colonization of GBS on vagina of pregnant women, preterm birth or premature rupture of fetal membranes and so on), related pathogens (bacteria strains, loads or virulence), immune level (inflammatory factor or neutralizing anticytokine auto-Abs), gene defect or primary immunodeficiencies of the hosts.
Female ; Humans ; Infant, Newborn ; Infectious Disease Transmission, Vertical ; Pregnancy ; Pregnancy Complications, Infectious/urine* ; Premature Birth ; Streptococcal Infections/urine* ; Streptococcus agalactiae/isolation & purification* ; Vagina/microbiology*

OBJECTIVETo investigate the clinical features of invasive candidiasis in children and the risk factors for Candida bloodstream infection.

METHODSA retrospective study was performed on 134 children with invasive candidiasis and hospitalized in 5 tertiary hospitals in Urumqi, China, between January 2010 and December 2015. The Candida species distribution was investigated. The clinical data were compared between the patients with and without Candida bloodstream infection. The risk factors for Candida bloodstream infection were investigated using multivariate logistic regression analysis.

RESULTSA total of 134 Candida strains were isolated from 134 children with invasive candidiasis, and non-albicans Candida (NAC) accounted for 53.0%. The incidence of invasive candidiasis in the PICU and other pediatric wards were 41.8% and 48.5% respectively. Sixty-eight patients (50.7%) had Candida bloodstream infection, and 45 patients (33.6%) had Candida urinary tract infection. There were significant differences in age, rate of use of broad-spectrum antibiotics, and incidence rates of chronic renal insufficiency, heart failure, urinary catheterization, and NAC infection between the patients with and without Candida bloodstream infection (P<0.05). The multivariate logistic regression analysis showed that younger age (1-24 months) (OR=6.027) and NAC infection (OR=1.020) were the independent risk factors for Candida bloodstream infection.

CONCLUSIONSThe incidence of invasive candidiasis is similar between the PICU and other pediatric wards. NAC is the most common species of invasive candidiasis. Candida bloodstream infection is the most common invasive infection. Younger age (1-24 months) and NAC infection are the risk factors for Candida bloodstream infection.

Adolescent ; Age Factors ; Candidiasis ; drug therapy ; microbiology ; Child ; Child, Preschool ; Female ; Fungemia ; etiology ; Humans ; Infant ; Infant, Newborn ; Logistic Models ; Male ; Retrospective Studies ; Risk Factors

OBJECTIVETo investigate the distribution of pathogens and bacterial resistance in children with severe community-acquired pneumonia (CAP).

METHODSA total of 522 children with severe CAP who were hospitalized in 2016 were enrolled as study subjects. According to their age, they were divided into infant group (402 infants aged 28 days to 1 year), young children group (73 children aged 1 to 3 years), preschool children group (35 children aged 3 to 6 years), and school-aged children group (12 children aged ≥6 years). According to the onset season, all children were divided into spring group (March to May, 120 children), summer group (June to August, 93 children), autumn group (September to November, 105 children), and winter group (December to February, 204 children). Sputum specimens from the deep airway were collected from all patients. The phoenix-100 automatic bacterial identification system was used for bacterial identification and drug sensitivity test. The direct immunofluorescence assay was used to detect seven common respiratory viruses. The quantitative real-time PCR was used to detect Mycoplasma pneumoniae (MP) and Chlamydia trachomatis (CT).

RESULTSOf all the 522 children with severe CAP, 419 (80.3%) were found to have pathogens, among whom 190 (45.3%) had mixed infection. A total of 681 strains of pathogens were identified, including 371 bacterial strains (54.5%), 259 viral strains (38.0%), 12 fungal strains (1.8%), 15 MP strains (2.2%), and 24 CT strains (3.5%). There were significant differences in the distribution of bacterial, viral, MP, and fungal infections between different age groups (P<0.05). There were significant differences in the incidence rate of viral infection between different season groups (P<0.05), with the highest incidence rate in winter. The drug-resistance rates of Streptococcus pneumoniae to erythromycin, tetracycline, and clindamycin reached above 85%, and the drug-resistance rates of Staphylococcus aureus to penicillin, erythromycin, and clindamycin were above 50%; they were all sensitive to vancomycin and linezolid. The drug-resistance rates of Haemophilus influenzae to cefaclor and cefuroxime were above 60%, but it was sensitive to cefotaxime. The drug-resistance rates of Escherichia coli and Klebsiella pneumoniae to ampicillin, cefotaxime, and ceftriaxone were above 60%, but they were sensitive to carbapenems and compound preparation of enzyme inhibitors.

CONCLUSIONSBacteria are the main pathogens in children with severe CAP and mixed infection is prevalent. The drug-resistance rates of these pathogenic bacteria are high.

Adolescent ; Bacteria ; drug effects ; isolation & purification ; Child ; Child, Preschool ; Community-Acquired Infections ; microbiology ; Drug Resistance, Bacterial ; Female ; Fluorescent Antibody Technique, Indirect ; Humans ; Infant ; Infant, Newborn ; Male ; Pneumonia ; microbiology

OBJECTIVETo study the pathogen distribution and risk factors of nosocomial infection in very preterm infants, as well as the risk of adverse outcomes.

METHODSA retrospective analysis was performed for the clinical data of 111 very preterm infants who were born between January and December, 2016 and had a gestational age of <32 weeks and a birth weight of <1 500 g. According to the presence or absence of nosocomial infection after 72 hours of hospitalization, the infants were divided into infection group and non-infection group. The infection group was analyzed in terms of pathogenic bacteria which caused infection and their drug sensitivity. A multivariate logistic regression analysis was used to investigate the potential risk factors and risk of adverse outcomes of nosocomial infection in very preterm infants.

RESULTSGram-negative bacteria were the main pathogens for nosocomial infection in very preterm infants and accounted for 54%, among which Pseudomonas aeruginosa was the most common one; the following pathogens were fungi (41%), among which Candida albicans was the most common one. The drug sensitivity test showed that Gram-negative bacteria were highly resistant to β-lactam and carbapenems and highly sensitive to quinolones, while fungi had low sensitivity to itraconazole and high sensitivity to 5-fluorocytosine and amphotericin B. Early-onset sepsis, duration of peripherally inserted central catheter, steroid exposure, and duration of parenteral nutrition were risk factors for nosocomial infection in very preterm infants (P<0.05). Compared with the non-infection group, the infection group had significantly higher risks of pulmonary complications (P<0.05), as well as a significantly longer length of hospital stay and a significantly higher hospital cost (P<0.001).

CONCLUSIONSNosocomial infection in very preterm infants is affected by various factors and may increase the risk of adverse outcomes. In clinical practice, reasonable preventive and treatment measures should be taken with reference to drug sensitivity, in order to improve the prognosis of very premature infants.

Cross Infection ; epidemiology ; etiology ; microbiology ; Female ; Gram-Negative Bacteria ; drug effects ; isolation & purification ; Health Care Costs ; Humans ; Infant, Newborn ; Infant, Premature ; Length of Stay ; Logistic Models ; Male ; Microbial Sensitivity Tests ; Retrospective Studies ; Risk Factors