Independent validation of an existing model enables prediction of hearing loss after childhood bacterial meningitis

Decrease in Rates of Hearing Loss From Pediatric Bacterial Meningitis Over Time: A Database Review

OBJECTIVES

Bacterial meningitis is a leading cause of acquired sensorineural hearing loss (SNHL). Treatment and prevention of bacterial meningitis have improved over time, but rates of neurologic complications have not been recently studied. The objective here is to present an updated population-based review of hearing loss as a sequela of bacterial meningitis.

METHODS

A retrospective cohort study was conducted between 2010 and 2022 of children discharged with bacterial meningitis, using the Pediatric Health Information System's (PHIS) database. Rates of hearing loss and mortality were evaluated over time.

RESULTS

A total of 6138 children with a primary diagnosis of bacterial meningitis were identified (3520 male [57.3%], mean age 5.8 months [2.0, 61.2]). Of these, 277 (4.51%) were diagnosed with hearing loss. Children with hearing loss were significantly older (23.6 vs. 5.3 months, p < 0.01), but differences in gender, race, or ethnicity had no association with hearing loss. Streptococcus pneumoniae, Hemophilus influenzae, and Neisseria meningiditis were associated with significantly higher rates of hearing loss than other etiologies (p < 0.01). Children with hearing loss had a higher rate of receiving dexamethasone than children without hearing loss. Overall mortality rate was 2.1%. Hearing loss and mortality demonstrated significant decreases over the study period.

CONCLUSION

Hearing loss remains a common sequela of bacterial meningitis despite widespread uptake of vaccines for preventing S. pneumoniae, H. influenzae, and N. meningitidis. Dexamethasone was not associated with decreased rates of hearing loss in this cohort. From 2010 to 2022, there was a significant decrease in overall rates of mortality and hearing loss for children with bacterial meningitis.

LEVEL OF EVIDENCE

3: retrospective case-control series Laryngoscope, 134:3820-3825, 2024.

Risk factors for infant hearing loss: a meta-analysis

Hearing loss is a common disability in infants that significantly impacts their cognitive, language, and literacy development. This study aimed to systematically assess the risk factors for the early identification and intervention in infant hearing loss. Databases were searched for meta-analyses of observational studies until November 2023. The quality assessment was performed using the Cochrane risk of bias tool, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the certainty of the evidence. A meta-analysis identified 14 risk factors significantly associated with infant hearing loss. According to the GRADE approach, there were four factors with moderate-certainty evidence (low birth weight(LBW), congenital anomalies, craniofacial anomalies, intracranial hemorrhages), seven factors with low-certainty evidence (ototoxic medications, family history of hearing loss, mechanical ventilation > 5 days, intrauterine infection, admission to neonatal intensive care unit (NICU) > 5 days, mechanical ventilation and asphyxia) and six with extremely-low-certainty evidence (very low birth weight < 1500 g (VLBW), hyperbilirubinemia, sepsis or meningitis, male sex, premature birth, small for gestational age (SGA)). Nevertheless, no significant association was found between infant hearing loss and factors such as small for gestational age (SGA), male sex, and premature birth (P > 0.05).  Conclusion: The identification of these 14 interrelated risk factors can prove advantageous in clinical practice, as these findings could guide hearing screening and parental counseling. Furthermore, prospective research could be conducted to develop risk-based scoring systems based on these factors. What is Known: • Infant hearing loss is a worldwide issue. • Risk factors for this condition are debated. What is New: • This is the first meta-analysis to comprehensively evaluate perinatal and postnatal risk factors for hearing loss in infants. • Intracranial hemorrhage, mechanical ventilation, and low birth weight are associated with infant hearing loss. However, no evidence of an association was found between premature birth, being small for gestational age, or male sex and hearing loss.

Development and validation of a novel model to predict pulmonary embolism in cardiology suspected patients: A 10-year retrospective analysis

As there are no predictive models for pulmonary embolism (PE) in patients with suspected PE at cardiology department. This study developed a predictive model for the probability of PE development in these patients. This retrospective analysis evaluated data from 995 patients with suspected PE at the cardiology department from January 2012 to December 2021. Patients were randomly divided into the training and validation cohorts (7:3 ratio). Using least absolute shrinkage and selection operator regression, optimal predictive features were selected, and the model was established using multivariate logistic regression. The features used in the final model included clinical and laboratory factors. A nomogram was developed, and its performance was assessed and validated by discrimination, calibration, and clinical utility. Our predictive model showed that six PE-associated variables (age, pulse, systolic pressure, syncope, D-dimer, and coronary heart disease). The area under the curve - receiver operating characteristic curves of the model were 0.721 and 0.709 (95% confidence interval: 0.676-0.766 and 0.633-0.784), respectively, in both cohorts. We also found good consistency between the predictions and real observations in both cohorts. In decision curve analysis, the numerical model had a good net clinical benefit. This novel model can predict the probability of PE development in patients with suspected PE at cardiology department.

Study protocol: The Dutch 20|30 Postmeningitis study: a cross-sectional follow-up of two historical childhood bacterial meningitis cohorts on long-term outcomes

Background

Bacterial meningitis (BM) is a serious, life-threatening infectious disease of the central nervous system that often occurs in young children. The most common severe to moderate sequelae following BM are sensorineural hearing loss, neuromotor disabilities and mental retardation, while subtle sequelae include academic and behavioral disabilities. It is largely unknown whether these more subtle sequelae persist into adolescence and adulthood. Therefore, this study will investigate the very long-term effects of childhood BM in later life. Better understanding of long-term effects and early identification of adverse outcomes after BM are essential for more timely interventions. Additionally, certain single nucleotide polymorphisms (SNPs) are associated with disease severity and might predict adverse sequelae. These include SNPs in genes encoding for pathogen recognition and immune response upon infection. Accordingly, a secondary objective of this study is to investigate the role of genetic variation in BM and use any insights to predict short- and long-term outcomes.

Methods

In the Dutch 20|30 Postmeningitis study, adolescents and young adults (n = 947) from two historical cohorts with a prior episode of BM during childhood will be enrolled into a cross-sectional follow-up investigation using mainly questionnaires that examine executive and behavioral functioning, health-related quality of life, subjective hearing, mood and sleeping disorders, academic performance, and economic self-sufficiency. The results will be compared to normative data by one-sample t-tests. Multivariable regression analysis will be used to assess for any associations with causative pathogens and severity of BM. Participants that complete the questionnaires will be approached to provide a swab for buccal DNA and subsequent sequencing analyses. Logistic regression models will be used to predict sequelae.

Discussion

The unique follow-up duration of this cohort will enable us to gain insights into the possible very long-term adverse effects of childhood BM and how these might impact on quality of life. The investigation of host genetic factors will contribute to the development of prediction models which will serve as prognostic tools to identify children who are at high risk of adverse outcome after BM.

Trial Registration

Dutch Trial Register NTR-6891. Retrospectively registered 28 December 2017.

Repeated Audiometry After Bacterial Meningitis: Consequences for Future Management

OBJECTIVE

Sensorineural hearing loss is a common sequela of bacterial meningitis. The objective of this study is to delineate the incidence and course of hearing loss after bacterial meningitis.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary referral center.

PATIENTS

Data of 655 patients who suffered from bacterial meningitis between 1985 and 2015 were analyzed.

INTERVENTIONS

None.

MAIN OUTCOME MEASUREMENTS

Availability of audiometric data, incidence of hearing loss, and onset and course of hearing loss.

RESULTS

In this cohort the incidence of hearing loss (>25 dB) was 28% (95% confidence interval 23-34%). The incidence of profound hearing loss (>80 dB) was 13% (95% confidence interval 10-18%). Normal hearing at the first assessment after treatment for meningitis remained stable over time in all these patients. In 19 of the 28 patients with diagnosed hearing loss, the hearing level remained stable over time. Hearing improved in six patients and deteriorated in two patients. One patient showed a fluctuating unilateral hearing loss.

CONCLUSION

Audiological tests in patients with bacterial meningitis, especially children, should be started as soon as possible after the acute phase is over. As we found no deterioration of initial normal hearing after bacterial meningitis, repeated audiometry seems indicated only for those with diagnosed hearing loss at first assessment.

Systematic Review: Incidence and Course of Hearing Loss Caused by Bacterial Meningitis: In Search of an Optimal Timed Audiological Follow-up

OBJECTIVE

The objective of this study was to clarify the incidence and course of hearing loss after bacterial meningitis to optimize the audiological follow-up.

DATA SOURCES

The databases Embase, Medline (OvidSP), Web-of-science, Scopus, Cinahl, Cochrane, PubMed publisher, and Google Scholar were used. Only articles written in English were included.

STUDY SELECTION

Articles published from 1985 until March 2015 describing the incidence, risk factors, or course of hearing loss after meningitis were used.

DATA EXTRACTION

The quality of the studies was assessed on three aspects: quality of audiometry, number of patients, and methodological quality.

DATA SYNTHESIS

For each publication, data were entered in spreadsheet software for analysis. The data were analyzed and interpreted using best evidence synthesis.

CONCLUSIONS

The overall quality of the included studies was poor. A major drawback was the quality of the (description of) audiometry, severity, and timing of hearing loss.A systematic review of the literature showed an incidence of hearing loss (>25 ± 5  dB) of 14% and an incidence of 5% for profound hearing loss (>90  dB). Patients with initial normal hearing after meningitis showed stable normal hearing over time. However, initial hearing loss related to meningitis can improve or deteriorate over time.We therefore recommend early audiological testing of all patients who suffered bacterial meningitis. However, long-term audiological follow-up is only needed for patients with early onset hearing loss and not for patients with normal hearing at the first hearing test.

Ataxia and Its Association with Hearing Impairment in Childhood Bacterial Meningitis

INTRODUCTION

Ataxia, deemed usually a minor sequela, follows childhood bacterial meningitis (BM) in up to 18% of cases. Although mostly transient and benign, it can predict permanent hearing loss and vestibular dysfunction. We explored the clinical meaning of ataxia by following its course in a large number of BM patients and examining its relation with hearing loss.

METHODS

The presence, degree (no, mild, moderate and severe) and course (transient, prolonged and late) of ataxia in BM were registered prospectively by predefined criteria. These data were compared with several patient, disease, and outcome variables including hearing loss (none, moderate, severe and profound) on day 7 of treatment and at a follow-up visit 1 month after discharge.

RESULTS

Ataxia was present in 243 of 361 (67%) patients on day 7, being slight in 21%, moderate in 38% and severe in 41%. Its course was transient in 41%, prolonged in 24% and late in 5%, whereas 30% of the patients did not present ataxia at any time. Ataxia associated most significantly not only with several measures of BM severity and suboptimal outcome (P < 0.0001), but also specifically, albeit not consistently, with hearing loss (P = 0.001). The degree of ataxia correlated with the extent of hearing loss (rho, 0.37; P < 0.0001).

CONCLUSIONS

Ataxia is more frequent and lasts longer after BM than learned from previous studies. The presence and intensity of ataxia associate with hearing loss and its magnitude.

Addition of host genetic variants in a prediction rule for post meningitis hearing loss in childhood: a model updating study

BACKGROUND

Sensorineural hearing loss is the most common sequela in survivors of bacterial meningitis (BM). In the past we developed a validated prediction model to identify children at risk for post-meningitis hearing loss. It is known that host genetic variations, besides clinical factors, contribute to severity and outcome of BM. In this study it was determined whether host genetic risk factors improve the predictive abilities of an existing model regarding hearing loss after childhood BM.

METHODS

Four hundred and seventy-one Dutch Caucasian childhood BM were genotyped for 11 single nucleotide polymorphisms (SNPs) in seven different genes involved in pathogen recognition. Genetic data were added to the original clinical prediction model and performance of new models was compared to the original model by likelihood ratio tests and the area under the curve (AUC) of the receiver operating characteristic curves.

RESULTS

Addition of TLR9-1237 SNPs and the combination of TLR2 + 2477 and TLR4 + 896 SNPs improved the clinical prediction model, but not significantly (increase of AUC's from 0.856 to 0.861 and from 0.856 to 0.875 (p = 0.570 and 0.335, respectively). Other SNPs analysed were not linked to hearing loss.

CONCLUSIONS

Although addition of genetic risk factors did not significantly improve the clinical prediction model for post-meningitis hearing loss, AUC's of the pre-existing model remain high after addition of genetic factors. Future studies should evaluate whether more combinations of SNPs in larger cohorts has an additional value to the existing prediction model for post meningitis hearing loss.

Single nucleotide polymorphisms in pathogen recognition receptor genes are associated with susceptibility to meningococcal meningitis in a pediatric cohort

Bacterial meningitis (BM) is a serious infection of the central nervous system, frequently occurring in childhood and often resulting in hearing loss, learning disabilities, and encephalopathy. Previous studies showed that genetic variation in innate immune response genes affects susceptibility, severity, and outcome of BM. The aim of this study is to describe whether single nucleotide polymorphisms (SNPs) in pathogen recognition gene products are associated with susceptibility to develop BM in single genes analysis as well as SNP combinations. Genotype frequencies of seven SNPs, in five immune response genes encoding for Toll-like receptors (TLRs), nucleotide oligomerization domain (NOD) proteins and caspase-1 (CASP1), in 391 children with meningococcal meningitis (MM) and 82 children with pneumococcal meningitis were compared with a large cohort of 1141 ethnically matched healthy controls. Carriage of TLR4 +896 GG mutant predisposed to susceptibility to develop MM (p = 1.2*10⁻⁵, OR  = 9.4, 95% CI  = 3.0–29.2). The NOD2 SNP8 mutant was significantly more frequent in MM patients compared to controls (p = 0.0004, OR  = 12.2, 95% CI  = 2.6–57.8). Combined carriage of TLR2 +2477 and TLR4 +896 mutants was strongly associated with MM (p = 4.2*10⁻⁵, OR  = 8.6, 95% CI  = 2.7–27.3). A carrier trait of TLR4 +896 and NOD2 SNP8 mutants was also strongly associated with susceptibility to develop MM (p = 4.2*10⁻⁵, OR  = 10.6, 95% CI  = 2.9–38.6). This study associates SNPs in TLR4 and NOD2 with susceptibility to develop MM.

Toll-like receptor 9 polymorphisms are associated with severity variables in a cohort of meningococcal meningitis survivors

BACKGROUND

Genetic variation in immune response genes is associated with susceptibility and severity of infectious diseases. Toll-like receptor (TLR) 9 polymorphisms are associated with susceptibility to develop meningococcal meningitis (MM). The aim of this study is to compare genotype distributions of two TLR9 polymorphisms between clinical severity variables in MM survivors.

METHODS

We used DNA samples of a cohort of 390 children who survived MM. Next, we determined the genotype frequencies of TLR9 -1237 and TLR9 +2848 polymorphisms and compared these between thirteen clinical variables associated with prognostic factors predicting adverse outcome of bacterial meningitis in children.

RESULTS

The TLR9 -1237 TC and CC genotypes were associated with a decreased incidence of a positive blood culture for Neisseria (N.) meningitidis (p = 0.014, odds ratio (OR) 0.5. 95% confidence interval (CI) 0.3 - 0.9). The TLR9 +2848 AA mutant was associated with a decreased incidence of a positive blood culture for N. meningitidis (p = 0.017, OR 0.6, 95% CI 0.3 - 0.9). Cerebrospinal fluid (CSF) leukocytes per μL were higher in patients carrying the TLR9 -1237 TC or CC genotypes compared to carriers of the TT wild type (WT) (p = 0.024, medians: 2117, interquartile range (IQR) 4987 versus 955, IQR 3938). CSF blood/glucose ratios were lower in TLR9 -1237 TC or CC carriers than in carriers of the TT WT (p = 0.017, medians: 0.20, IQR 0.4 versus 0.35, IQR 0.5). CSF leukocytes/μL were higher in patients carrying the TLR9 +2848 AA mutant compared to carriers of GG or GA (p = 0.0067, medians: 1907, IQR 5221 versus 891, IQR 3952).

CONCLUSIONS

We identified TLR9 genotypes associated with protection against meningococcemia and enhanced local inflammatory responses inside the central nervous system, important steps in MM pathogenesis and defense.