Central Nervous System Infections in Children: An Ongoing Challenge!

Pediatric non-congenital central nervous system infections: role of imaging in the emergency department

Neurological emergencies in pediatric patients, including central nervous system infections like meningitis and encephalitis, account for significant morbidity and mortality. Neuroimaging plays an important role in the management of these infections, especially when children present with non-specific symptoms such as fever, seizures, or altered consciousness. While computed tomography scans are typically the initial imaging step, magnetic resonance imaging is preferred for its superior detail and lack of ionizing radiation. Radiologists play a crucial role in guiding clinicians to select the appropriate imaging modality based on clinical presentation, patient age, and available technology. Optimizing techniques for these studies may help to give an overview of imaging protocols and an optimal diagnostic algorithm for these patients. In this article, we delineate the prevalent radiological manifestations associated with the primary etiological agents of central nervous system infections, encompassing bacteria, fungi, viruses, and parasites. Furthermore, we share our clinical experience with particular radiologic findings in select pathologies, underscoring the critical importance of evaluating these non-congenital infections within the context of emergency medical care.

Clinical utility of the FilmArray® meningitis/encephalitis panel in children with suspected central nervous system infection in a low-resource setting - a prospective study in Southwestern Uganda

BACKGROUND

In low-resource settings, limited laboratory capacity adds to the burden of central nervous system (CNS) infections in children and spurs overuse of antibiotics. The commercially available BioFire® FilmArray® Meningitis/Encephalitis Panel (FA-ME) with its capability to simultaneously detect 14 pathogens in cerebrospinal fluid (CSF), could potentially narrow such a diagnostic gap.

METHODS

In Mbarara, Uganda, we compared clinical utility (clinical turnaround time [cTAT], microbial yield, and influence on patient outcome and antibiotic exposure) of FA-ME with bacterial culture, in children 0-12 years with suspected CNS infection.

RESULTS

Of 212 enrolled children, CSF was sampled from 194. All samples underwent bacterial culture, of which 193 also underwent FA-ME analyses. FA-ME analyses prospectively influenced care for 169 of the 193 patients, and they constituted an 'Index group'. The remaining 43/212 patients constituted a 'Reference group'. Of all 194 CSF-sampled patients, 87% (168) had received antibiotics before lumbar puncture. Median cTAT for FA-ME was 4.2 h, vs. two days for culture. Bacterial yield was 12% (24/193) and 1.5% (3/194) for FA-ME and culture, respectively. FA-ME viral yield was 12% (23/193). Fatality rate was 14% in the Index group vs. 19% in the Reference group (P = 0.20). From clinician receival of FA-ME results, median antibiotic exposure was 6 days for bacteria-negative vs. 13 days for bacteria-positive patients (P = 0.03). Median hospitalization duration was 7 vs. 12 days for FA-ME negative and positive patients, respectively (P < 0.01).

CONCLUSIONS

In this setting, clinical FA-ME utility was found in a higher and faster microbial yield and shortened hospitalization and antibiotic exposure of patients without CSF pathology. More epidemiologically customized pathogen panels may increase FA-ME utility locally, although its use in similar settings would require major cost reductions.

TRIAL REGISTRATION

The trial was registered with clinicaltrials.gov (NCT03900091) in March 2019, and its protocol was published in November 2020.

Pentraxin 3: a novel biomarker in pediatric central nervous system infections

BACKGROUND

Pediatric CNS infections have been identified as a global health problem, associated with an increased death rate and fatal consequences. Pentraxin 3 (PTX3) is an acute-phase mediator that increases in body fluids and plasma throughout inflammation. Our study was designed to assess the diagnostic and prognostic value of cerebrospinal fluid (CSF) PTX3 levels in pediatric patients with different central nervous system (CNS) infections.

METHODS

We enrolled 100 children hospitalized at Fayoum University Children's Hospital with suspected CNS infections fulfilling the case criteria for CNS infections. We recorded their medical history and examination data upon admission. The C-reactive protein (CRP) level, complete blood count (CBC), CSF PTX3 level, CSF analysis and culture, and blood culture were assessed in all patients at the time of admission.

RESULTS

Levels of PTX3 were significantly correlated with the duration of symptoms before admission, length of hospital stay, patient outcomes, CRP levels, CSF findings, and CSF cultures (P value < 0.001). Patients who needed mechanical ventilation or experienced adverse outcomes had greater levels of PTX3, which were more prevalent in those with a bacterial etiology (P value < 0.05).

CONCLUSION

PTX3 indicates disease severity and prognosis. PTX3 showed statistically significant sensitivity when discriminating between bacterial and aseptic CNS infections, as well as between bacterial CNS infections and controls. However, it has lower sensitivity and specificity than other CSF biomarkers, though it is higher than serum CRP.

Changes in optic nerve sheath diameter and its correlation with degree of consciousness, pupil diameter, and light reflex in children with central nervous system infection after osmotherapy

Background

High intracranial pressure (ICP) is one of the most common complications of central nervous system (CNS) infection. Failure to control high intracranial pressure results in brain herniation and death. One of the treatments for high ICP involves the administration of osmotherapy in the form of 3% NaCl or 20% mannitol with observation during administration. Observation of ICP during administration of osmotherapy is possible through measurement of optic nerve sheath diameter (ONSD), which could be correlated with degree of consciousness, pupil diameter, and light reflex. Previous studies have not correlated ONSD with degree of consciousness, pupil diameter, and light reflex during the administration of osmotherapy.

Purpose

To provide insights of incorporating ONSD measurement as a form of non-invasive bedside method for ICP monitoring by correlating it with degree of consciousness, pupil diameter, and light reflex at several time points.

Methods

This study is a prospective cohort study, performed at Dr. Hasan Sadikin General Central Hospital Bandung, Cibabat General Regional Hospital, and General Regional Hospital Bandung Kiwari on children aged 2-18 years with decreased consciousness and CNS infection, from June 2023. Inter-rater reliability was performed with a correlation coefficient of 0.90. Measurement of ONSD, degree of consciousness, pupil diameter, and light reflex simultaneously up to 48 h after initiation of osmotherapy to 30 patients. Correlational analyses were performed using Spearman's rank.

Results

Observation for 48 h after administration of osmotherapy showed changes in ONSD. A significant positive correlation was found between ONSD and degree of consciousness (r = 0.621 for the right eye and r = 0.602 for the left eye, p < 0.001). A significant positive correlation was found between ONSD and light reflex (r = 0.801 for the right eye and r = 0.812 for the left eye, p < 0.001). No significant correlation was found with changes of pupil diameter (r = -0.136 for the right eye and r = -0.141 for the left eye, p > 0.05).

Conclusion

A significant correlation was found between ONSD and degree of consciousness and light reflex in children aged 2-18 years with CNS infection during administration of osmotherapy.

Profile of Pediatric Neurosurgery in Nigeria from 1962 to 2021: A Systematic Review

OBJECTIVE

This study aims to provide a comprehensive overview of pediatric neurosurgery in Nigeria, since 1962, by assessing epidemiological data, management strategies, and case outcomes.

METHODS

A systematic bibliometric review of Nigerian neurosurgical literature was reported with the PRISMA guidelines. The Risk of Bias Assessment Tool was applied to all nonrandomized studies, and a descriptive analysis was performed for all variables.

RESULTS

We identified 12,295 pediatric patients from 196 published studies. Most publications (72.4%) occurred in the recent 2 decades, of which 40.3% were observational case reports/series. The patients were predominantly male (57.2%) and aged 0-18 years, with the majority (66.1%) belonging to the 0-5 age range. Most patients (63.4%) presented between 1-12 months. The most common presenting feature was altered consciousness (7.7%), with computed tomography (38.8%) being the most frequently utilized diagnostic imaging modality. The diagnoses with the greatest prevalence (60.2%) were congenital abnormalities such as hydrocephalus and neural tube defects. 57.5% of cases received surgical therapy, with ventriculoperitoneal shunt placement being the most noticeable procedure performed (36.4%). Complications were identified in 9.5% of cases, with a 4.5% death rate. The Glasgow Outcome Score (95.7%) was the primary outcome measure utilized, with positive outcomes reported in 59.3% of cases.

CONCLUSIONS

This review provides significant epidemiological data which emphasizes the country's enormous burden of pediatric neurosurgical cases. The findings can help guide clinical decisions as well as future research and policy development.

Diagnostic performance of metagenomic next-generation sequencing for the detection of pathogens in cerebrospinal fluid in pediatric patients with central nervous system infection: a systematic review and meta-analysis

BACKGROUND

Detecting pathogens in pediatric central nervous system infection (CNSI) is still a major challenge in medicine. In addition to conventional diagnostic patterns, metagenomic next-generation sequencing (mNGS) shows great potential in pathogen detection. Therefore, we systematically evaluated the diagnostic performance of mNGS in cerebrospinal fluid (CSF) in pediatric patients with CNSI.

METHODS

Related literature was searched in the Web of Science, PubMed, Embase, and Cochrane Library. We screened the literature and extracted the data according to the selection criteria. The quality of included studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool and the certainty of the evidence was measured by the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) score system. Then, the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odd's ratio (DOR), and area under the curve (AUC) of the summary receiver operating characteristic curve (sROC) were estimated in Stata Software and MetaDisc. Subgroup analyses were performed to investigate the potential factors that influence the diagnostic performance.

RESULTS

A total of 10 studies were included in the meta-analysis. The combined sensitivity was 0.68 (95% confidence interval [CI]: 0.59 to 0.76, I2 = 66.77%, p < 0.001), and the combined specificity was 0.89 (95% CI: 0.80 to 0.95, I2 = 83.37%, p < 0.001). The AUC of sROC was 0.85 (95% CI, 0.81 to 0.87). The quality level of evidence elevated by the GRADE score system was low.

CONCLUSIONS

Current evidence shows that mNGS presents a good diagnostic performance in pediatric CNSI. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusion.

Pediatric central nervous system infections in the Amazon: clinical and laboratory profiles

Background

Central nervous system (CNS) infections are important causes of mortality and morbidity in children, and they are related to severe problems such as hearing loss, neurological sequelae, and death. The objective was to describe clinical and laboratory exam profiles of children who were diagnosed with CNS infections.

Methods

We conducted a cross-sectional study based on medical records, which included pediatric patients aged from 3 months to 15 years, with a clinical suspicion of CNS infection between January 2014 to December 2019. The pathogens were confirmed in cerebrospinal fluid (CSF) samples using Gram staining, cell culture, molecular diagnostics (PCR and qPCR), and serology.

Results

Out of the 689 enrolled patients, 108 (15.6%) had laboratory-confirmed infections in CSF. The most common bacterial pathogens isolated from the culture were Neisseria meningitidis serogroup C in 19, Streptococcus pneumoniae in 11, and Haemophilus influenzae in seven samples. The viruses identified were Enterovirus, Cytomegalovirus, Varicella-zoster virus, Epstein-Barr virus, and arbovirus. No patient was found to be positive for Herpes simplex virus 1 and 2. Patients with viral infections showed altered levels of consciousness (p = 0.001) when compared to bacterial infections.

Conclusion

This study shows the presence of important vaccine-preventable pathogens, and different families of viruses causing CNS infections in the pediatric patients of Manaus.

Diagnosis of Neurological Infections in Pediatric Patients from Cell-Free DNA Specimens by Using Metagenomic Next-Generation Sequencing

Central nervous system (CNS) infections can cause significant morbidity and mortality, especially in children. Rapid and accurate pathogenic detection in suspected CNS infections is essential for disease control at the early stage of infection. To evaluate the performance of metagenomic next-generation sequencing (mNGS) of cell-free DNA (cfDNA) in cerebrospinal fluid (CSF) in pediatric patients, we retrospectively analyzed the efficiency of cfDNA mNGS in children with CNS infections (n = 257) or noninfectious neurological disorders (n = 81). The CSF samples of 124 random subjects were used to evaluate the accuracy between mNGS of cfDNA and whole-cell DNA (wcDNA). In total, cfDNA mNGS detected a wide range of microbes with a detection rate of 71.0%, and the sensitivity and total coincidence rate with clinical diagnosis reached 68.9% and 67.5%, respectively. Compared with wcDNA mNGS, cfDNA mNGS had a higher efficacy in detecting viruses (66 versus 13) and Mycobacterium (7 versus 1), with significantly higher reads per million. The dominant causative pathogens were bacteria and viruses in CNS infections, but these presented with different pathogen spectra in different age categories. The best timing for the mNGS test ranged from 1 to 6 days after the start of anti-infection therapy, and the earlier mNGS started, the better was identification of bacterial CNS infections. This study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in pediatric CNS infections, and it was even better than wcDNA mNGS. Furthermore, research needs to be better validated in large-scale clinical trials to improve the clinical applications of cfDNA mNGS. IMPORTANCE Our study emphasized that cfDNA mNGS had overall superiority to conventional methods on causative pathogen detection in CNS-infected children, and it was even better than wcDNA mNGS. cfDNA mNGS detected a wide range of pathogens with a high total coincidence rate (67.5%) against clinical diagnosis. The best timing for cfDNA mNGS detection ranged from 1 to 6 days, rather than 0 days, after the start of empirical anti-infection therapy. The earlier mNGS started, the better the identifications of bacterial CNS infections. To the best of our knowledge, this research is the first report evaluating the clinical utility of mNGS with different methods (cfDNA versus wcDNA) of extracting DNA from CSF specimens in diagnosing pediatric CNS infections. Meanwhile, this is the largest cohort study that has evaluated the performance of mNGS using cfDNA from CSF specimens in pediatric patients with CNS infections.

Neurological manifestations of scrub typhus infection: A systematic review and meta-analysis of clinical features and case fatality

BACKGROUND

Scrub typhus has become a leading cause of central nervous system (CNS) infection in endemic regions. As a treatable condition, prompt recognition is vital. However, few studies have focused on describing the symptomology and outcomes of neurological scrub typhus infection. We conducted a systematic review and meta-analysis to report the clinical features and case fatality ratio (CFR) in patients with CNS scrub typhus infection.

METHODS

A search and analysis plan was published in PROSPERO [ID 328732]. A systematic search of PubMed and Scopus was performed and studies describing patients with CNS manifestations of proven scrub typhus infection were included. The outcomes studied were weighted pooled prevalence (WPP) of clinical features during illness and weighted CFR.

RESULTS

Nineteen studies with 1,221 (656 adults and 565 paediatric) patients were included. The most common clinical features in CNS scrub typhus were those consistent with non-specific acute encephalitis syndromes (AES), such as fever (WPP 100.0% [99.5%-100.0%, I2 = 47.8%]), altered sensorium (67.4% [54.9-78.8%, I2 = 93.3%]), headache (65.0% [51.5-77.6%, I2 = 95.1%]) and neck stiffness 56.6% (29.4-80.4%, I2 = 96.3%). Classical features of scrub typhus were infrequently identified; an eschar was found in only 20.8% (9.8%-34.3%, I2 = 95.4%) and lymphadenopathy in 24.1% (95% CI 11.8% - 38.9%, I2 = 87.8%). The pooled CFR (95% CI) was 3.6% (1.5%- 6.4%, I2 = 67.3%). Paediatric cohorts had a CFR of 6.1% (1.9-12.1%, I2 = 77%) whilst adult cohorts reported 2.6% (0.7-5.3%, I2 = 43%).

CONCLUSION

Our meta-analyses illustrate that 3.6% of patients with CNS manifestations of scrub typhus die. Clinicians should have a high index of suspicion for scrub typhus in patients presenting with AES in endemic regions and consider starting empiric treatment whilst awaiting results of investigations, even in the absence of classical signs such as an eschar or lymphadenopathy.

Evaluation of the BioFire® FilmArray® Meningitis/Encephalitis panel in an adult and pediatric Ugandan population

BACKGROUND

Meningitis causes significant mortality in sub-Saharan Africa and limited diagnostics exist. We evaluated the utility of the BioFire® FilmArray® Meningitis/Encephalitis multiplex PCR panel (BioFire ME) in HIV-infected adults and HIV-infected and uninfected children presenting with suspected meningitis in Uganda.

METHODS

We tested cerebrospinal fluid (CSF) using a stepwise meningitis diagnostic algorithm including BioFire ME. We determined the diagnostic performance of BioFire ME for cryptococcal meningitis, using cryptococcal antigen (CrAg) and CSF culture as reference standards, and assessed other central nervous system (CNS) pathogens identified by the panel.

RESULTS

We evaluated 328 adult and 42 pediatric CSF specimens using BioFire ME. Of the adult CSF samples tested, 258 were obtained at baseline, and 70 were obtained from repeat lumbar punctures in cryptococcal meningitis. For Cryptococcus, sensitivity was 82%, specificity was 98%, PPV was 98%, and NPV was 79% in baseline specimens using CSF CrAg as the reference standard. Among follow-up specimens, a negative BioFire ME for Cryptococcus predicted CSF culture sterility with 84% NPV. Overall sensitivity was decreased at low fungal burdens: 29% for 0-99 Cryptococcus CFU/mL compared to 94% for ≥100 CFU/mL in baseline specimens. Other pathogens detected included E. Coli, H. influenzae, S. pneumoniae, CMV, enterovirus, HSV, HHV-6, and VZV. Two specimens tested positive for S. pneumoniae and one for Cryptococcus in the pediatric population.

CONCLUSIONS

Multiplex PCR is a promising rapid diagnostic test for meningitis in adults and children in resource-limited settings. Cryptococcus at low fungal burdens in CSF may be missed by BioFire ME.