Recent trends in pediatric bacterial meningitis in Japan, 2016-2018 - S. agalactiae has been the most common pathogen

Epidemiology and Outcomes of Neonatal Meningitis: Results of the Turkish Neo-Meningitis Nationwide Study

OBJECTIVE

To investigate the incidence and etiology of neonatal meningitis and to assess the associated risk factors, complications and outcomes in a nationwide multicenter retrospective descriptive study.

METHOD

Twenty-seven centers from 7 geographical regions participated in the study. Newborns with a positive cerebrospinal fluid culture and/or cerebrospinal fluid polymerase chain reaction were included in the study. Demographic characteristics, clinical, laboratory and neuroimaging findings and mortality characteristics were analyzed.

RESULTS

A total of 634 confirmed cases of neonatal meningitis were included in the final analysis. The incidence was 2.51 per 1000 intensive care unit hospitalizations and mortality was observed in 149 (23.5%). Gram-positive bacteria were the predominant pathogens (54.5%), with coagulase-negative Staphylococci accounting for 45.3% of the cases, followed by Gram-negative organisms (37.3%). Viral and fungal organisms were isolated in 3.2% and 1.7% of the infants, respectively. Gram-negative culture growth was more common in infants who died (51% vs. 34.6%; P < 0.001). In the multivariable model, the odds of mortality was higher in those with respiratory distress requiring invasive ventilatory support [odds ratio (OR): 10.3; 95% confidence interval (CI): 4.9-21.7; P < 0.01], hypotension requiring inotropes (OR: 4.4; 95% CI: 2.7-7.1; P < 0.001), low birth weight status (OR: 2.5; 95% CI: 1.4-4.6; P = 0.002), lack of exposure to antenatal steroids (OR: 2.4; 95% CI: 1.3-4.4; P = 0.005) and the presence of concomitant sepsis (OR: 1.9; 95% CI: 1.1-3.2; P = 0.017).

CONCLUSIONS

In this nationwide study, neonatal meningitis was found to be associated with high mortality. Coagulase-negative Staphylococci was the most common causative microorganism followed by Gram-negative bacteria. Severe clinical presentation with invasive mechanical ventilation and inotrope requirement, as well as concomitant sepsis, low birth weight status and lack of exposure to antenatal steroids, were found to be independent risk factors for mortality.

Group B Streptococcal Disease in Infants in Japan

This review describes the epidemiology of group B Streptococcus (GBS) infection in infants in Japan and discusses unresolved issues and future perspectives. Guidelines for the prevention of vertical transmission in Japan were implemented in 2008. The incidence of early-onset disease in Japan has remained stable at approximately 0.10/1000 livebirths or less, which is lower than in Europe and North America. The incidence of late-onset disease is also low, but has increased over the last decade, with an estimated 0.29/1000 livebirths in 2020. National surveillance studies in 2011-2015 and 2016-2020 reported case fatality rates of 4.5% and 6.5% for early-onset disease and 4.4% and 3.0% for late-onset disease, respectively. Sequelae of neurodevelopmental impairments were considerably associated with infants who developed meningitis. Predominant neonatal invasive strains have remained in the following order of serotypes: III, Ia, Ib and V, for the past 30 years. Conversely, the predominant serotypes of maternal colonization strains markedly changed from serotypes VI and VIII around 2000 to serotypes Ia, Ib, III and V over the last decade. Recurrence rates among infants < 1-year-old were estimated to be 2.8%-3.7%, and preterm birth and antenatal maternal GBS colonization were risk factors for recurrence. Several unresolved issues remain. First, the exact disease burden remains unclear because Japan does not have a nationwide system to register all infants affected by invasive GBS disease, and even population-based surveys are limited to up to 10 of the 47 prefectures. Others include low adherence to prevention guidelines of vertical transmission and the development of strategies based on Japanese epidemiological evidence rather than the Center for Disease Control and Prevention guidelines. The effectiveness of introducing maternal vaccines in Japan, where the disease incidence is low, needs to be carefully verified.

Cost-effectiveness analysis of 20-valent pneumococcal conjugate vaccine for routine pediatric vaccination programs in Japan

BACKGROUND

The Japanese National Immunization Program currently includes the pediatric 13 valent pneumococcal conjugate vaccine (PCV13) to prevent pneumococcal infections. We aimed to evaluate the cost-effectiveness of 20-valent PCV (PCV20) as a pediatric vaccine versus PCV13.

METHODS

A decision-analytic Markov model was used to estimate expected costs, quality-adjusted life-years (QALYs), and prevented cases and deaths caused by invasive pneumococcal disease, pneumonia, and acute otitis media over a ten-year time horizon from the societal and healthcare payer perspectives.

RESULTS

PCV20 was dominant, i.e. less costly and more effective, over PCV13 (gained 294,599 QALYs and reduced Japanese yen [JPY] 352.6 billion [2.6 billion United States dollars, USD] from the societal perspective and JPY 178.9 billion [USD 1.4 billion] from the payer perspective). Sensitivity and scenario analyses validated the robustness of the base scenario results. When comparing PCV20 with PCV13, the threshold analysis revealed an incremental cost-effectiveness ratio that was within the threshold value (JPY 5 million/QALY) at a maximum acquisition cost of JPY 74,033 [USD 563] (societal perspective) and JPY 67,758 [USD 515] (payer perspective).

CONCLUSIONS

As a pediatric vaccine, PCV20 was dominant over PCV13 regardless of the study perspective.

Development a prediction model for identifying bacterial meningitis in young infants aged 29-90 days: a retrospective analysis

BACKGROUND

The early diagnosis and treatment of bacterial meningitis (BM) in young infants was very critical. But, it was difficult to make a definite diagnosis in the early stage due to nonspecific clinical symptoms. Our objectives were to find the risk factors associated with BM and develop a prediction model of BM especially for young infants.

METHODS

We retrospectively reviewed the clinical data of young infants with meningitis between January 2011 and December 2020 in Children's Hospital of Soochow University. The independent risk factors of young infants with BM were screened using univariate and multivariate logistic regression analyses. The independent risk factors were used to construct a new scoring model and compared with Bacterial Meningitis Score (BMS) and Meningitis Score for Emergencies (MSE) models.

RESULTS

Among the 102 young infants included, there were 44 cases of BM and 58 of aseptic meningitis. Group B Streptococcus (22, 50.0%) and Escherichia coli (14, 31.8%) were the main pathogens of BM in the young infants. Multivariate logistic regression analysis identified procalcitonin (PCT), cerebrospinal fluid (CSF) glucose, CSF protein as independent risk factors for young infants with BM. We assigned one point for CSF glucose ≤ 1.86 mmol/L, two points were assigned for PCT ≥ 3.80 ng/ml and CSF protein ≥ 1269 mg/L. Using the not low risk criterion (score ≥ 1) with our new prediction model, we identified the young infantile BM with 100% (95% CI 91.9%-100%) sensitivity and 60.3% (95% CI 46.4%-72.9%) specificity. Compared with BMS and MSE model, our prediction model had larger area under receiver operating characteristic curve and higher specificity, the differences were statistically significant.

CONCLUSION

Our new scoring model for young infants can facilitate early identification of BM and has a better performance than BMS and MSE models.

Edwardsiella tarda is an Important Causative Agent of Maternal-Fetal Infections in Pregnant Women: a Case Report and Japanese Literature Review

We present a case study of a 6-day-old male infant who was referred to our hospital for fever, jaundice, and poor suckling, and was diagnosed with meningitis due to Edwardsiella tarda. We were able to detect E. tarda DNA after performing broad-range polymerase chain reaction targeting the bacterial 16S rRNA gene followed by a Basic Local Alignment Search Tool analysis of the DNA extracted from the cerebrospinal fluid. Furthermore, Japanese literature review showed that E. tarda caused perinatal invasive infections in mothers and infants and that the risk of fetal meningitis might be related to the food preference of Japanese people for raw fish. It is crucial to disseminate the information that pregnant women should refrain from eating high-risk raw fish, including freshwater fish.

Be aware of Extended-spectrum β-lactamase-producing Escherichia coli in neonates and Listeria monocytogenes in young children with bacterial meningitis in Japan

Nationwide surveillance of pediatric bacterial meningitis in Japan from 2019 to 2021 revealed two uncommon situations not covered by the recommended empiric treatment that were not rare in Japan, namely, extended-spectrum β-lactamase-producing-producing Escherichia coli in neonates and Listeria monocytogenes in children older than 1 month.

Changes in pathogens of neonatal bacterial meningitis over the past 12 years: a single-center retrospective study

BACKGROUND

Bacterial meningitis is a serious central nervous system infection associated with high morbidity and mortality during the neonatal period, while the pathogen distribution was rarely reported on a large scale in China. This study aimed to investigate the distribution and change trends of neonatal bacterial meningitis pathogens in Children's Hospital of Fudan University over the past 12 years.

METHODS

This retrospective study included all cases diagnosed with neonatal bacterial meningitis and admitted to our hospital from 2009 to 2020.

RESULTS

Totally 231 cases were enrolled, including 128 (55.4%) for male, 72 (31.2%) for premature infants, 48 (20.8%) for early-onset meningitis. The most common pathogens were Escherichia coli (E. coli) (39.0%) and Group B Streptococcus (GBS) (22.1%). Gram-negative bacteria were more common in preterm infants than in full-term infants (P=0.005). GBS was more common in term infants (P=0.000); Klebsiella pneumoniae (P=0.000) and Enterobacter cloacae (P=0.034) were more common in preterm infants. Gram-positive bacteria were more frequent in early-onset meningitis than in late-onset meningitis (P=0.002). Both E. coli (46.3% vs. 30.9%, P=0.017) and GBS (29.8% vs. 13.6%, P=0.003) increased, and Enterococcus (3.3% vs. 12.7%, P=0.008) decreased significantly in the epoch from 2015 to 2020 compared with the epoch from 2009 to 2014.

CONCLUSIONS

GBS and E. coli are the most common pathogens of neonatal bacterial meningitis in our hospital, and both have shown an upward trend over the past 12 years.

Clinical and Bacteriological Analysis of Pediatric Pneumococcal Meningitis after 13-Valent Pneumococcal Conjugate Vaccine Introduction in Japan

Streptococcus pneumoniae is one of the leading causes of meningitis in children. In Japan, since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), the number of pneumococcal meningitis due to non-PCV13 serotypes in children has increased. To clarify the clinical outcomes, serotype distributions, and antimicrobial susceptibility of isolated S. pneumoniae strains from pediatric pneumococcal meningitis, we clinically and bacteriologically analyzed 34 cases of pediatric pneumococcal meningitis that were reported after the PCV13 introduction era in Japan. The median age at diagnosis was 1 year (range: 3 months–13 years). Ten (29.4%) patients had underlying diseases. Twenty-nine (85.3%) patients had received at least one dose of any pneumococcal vaccine. Of the 34 patients with pneumococcal meningitis, 6 had sequelae, and 4 died. Nine (26.5%) strains were resistant to penicillin; five (15%) strains to meropenem, with an MIC of 0.5 μg/mL. All strains were susceptible to vancomycin and linezolid. Daptomycin’s MIC₅₀ was 0.064 μg/mL and MIC₉₀ was 0.094 μg/mL. Among the tested strains, only four were PCV13 serotypes. Penicillin-resistant S. pneumoniae was isolated from 30.0% of the patients with sequelae and death. Particularly, the proportion of serotype 10A in the sequelae and deceased cases was significantly higher than that in the complete recovery cases. We should carefully monitor the serotype and drug susceptibility of S. pneumoniae strains isolated from patients with meningitis after the PCV13 era and reconsider the treatment strategy to prepare against further drug-resistant pneumococcal strains.

IMPORTANCE We analyzed 34 cases of pediatric pneumococcal meningitis that were reported after the 13-valent pneumococcal conjugate vaccine (PCV13) introduction era in Japan. Our study revealed that pneumococcal meningitis in children was mainly caused by non-PCV13 serotypes; all cases with sequelae and death were caused by non-PCV13 serotypes. Moreover, all serotypes of penicillin resistant Streptococcus pneumoniae strains (26.5%; 9/34) were non-PCV13 serotypes. We also analyzed antimicrobial susceptibilities of glycopeptides, linezolid (LZD), and daptomycin (DAP) of isolated S. pneumoniae strains. All tested strains were susceptible to vancomycin, teicoplanin, LZD, and DAP. Especially. DAP demonstrated the best outcome among the tested antibiotics, with MIC₉₀ of 0.094 μg/mL. Pneumococcal meningitis in children continues to persist and is difficult to control with the current conjugate vaccines. Therefore, it is important to monitor the serotype and antimicrobial susceptibility of S. pneumoniae strains isolated from patients with meningitis and accordingly reconsider the treatment strategy.

Drastic reduction in pneumococcal meningitis in children owing to the introduction of pneumococcal conjugate vaccines: Longitudinal analysis from 2002 to 2016 in Japan

INTRODUCTION

The characteristics of pneumococcal isolates and their associations with outcomes in pediatric meningitis are unclear. This study aimed to clarify serotypes and resistance genotypes of Streptococcus pneumoniae from children with meningitis and evaluate the patient prognoses and backgrounds.

METHODS

Large-scale surveillance was conducted from 2002 to 2016 through periods I-V. Serotypes and penicillin (PEN) resistance genotypes were analyzed for pneumococcal isolates (n = 459) and cerebrospinal fluid (CSF) samples (n = 25). Furthermore, underlying diseases (n = 251), prognoses (n = 202), and laboratory data were evaluated.

RESULTS

The number of meningitis cases decreased drastically after the introduction of 7-valent pneumococcal conjugate vaccine (PCV7) to -53.6% and after switching to PCV13 to -70.2%. In particular, this reduction was apparent at ≤3 years of age. The proportion of the PCV7 serotype decreased sharply from 70.1% before introduction to 2.6% during period V; however, the non-vaccine type increased from 17.5% to 87.2%. The PEN resistance rate (gPRSP) was decreased from approximately 49% to 12.2% during period V. Among cases revealed prognosis, sequelae and mortality rates were 16.3% and 5.4%, respectively. The rate of the patients with underlying diseases was 26.3% and relatively high in ≥6 years. Laboratory data associated with a poor prognosis were low white blood cell count (<12.7 × 10³/μL), low platelet count (<28.1 × 10⁴/μL), low CSF-glucose (<36 mg/dL), and high CSF-protein (≥142 mg/dL).

CONCLUSIONS

Changes in serotype prevalence warrant continuous monitoring to observe future trends of pneumococcal meningitis, and further developments in multivalent conjugate vaccines are required.