Lack of cerebrospinal fluid pleocytosis in young infants with enterovirus infections of the central nervous system

Neurodevelopmental Outcomes Following Childhood Viral Meningitis in Canterbury New Zealand

BACKGROUND

Most childhood meningitis is viral in countries with widespread conjugate vaccine use. This study assessed clinical features and neurodevelopmental outcomes in preschool children following enteroviral and parechoviral meningitis.

METHODS

Children 18-42 months of age in Canterbury, New Zealand were included, who had enterovirus (EV) or parechovirus (HPEV) meningitis from 2015 to 2021. Comprehensive neurodevelopmental assessments were completed by a psychologist using the Bayley Scale for Infant Development-3 (BSID-3). Mean composite and scaled scores and proportion below the cutoff were assessed in each domain. Clinical data was analyzed.

RESULTS

There were 79 children 18-42 months old with previous EV or HPEV meningitis. BSID assessments were completed for 33 children (55% male), median age 32 months, from 2019 to 2022 including 23 with EV and 10 HPEV meningitis. At diagnosis, 32 (97%) received intravenous/intramuscular antibiotics, and 6 received a fluid bolus. Parents reported developmental speech concerns in 6 children, and delayed motor milestones in 1 child. There was no reported sensorineural hearing loss. BSID mean composite scores were in the expected range for cognition 102 (confidence interval: 98-106), language 96 (93-100) and motor 102 (98-106) domains. Overall, 12/33 (36%) children had below expected scores in 1 developmental domain, including scores 1-2 SD below the normative mean for cognition (2/33; 6%), receptive language (6/33; 18%), expressive language (5/33; 15%) and gross motor (6/33; 18%). There were no differences between scores in EV and HPEV meningitis.

CONCLUSION

Following viral meningitis, more than a third of preschool children had a mild developmental delay with comprehensive neurodevelopmental assessment, suggesting targeted follow-up should be considered.

Enterovirus Meningitis without Pleocytosis: a Retrospective Observational Study in Adults

Reverse-transcription polymerase chain reaction (RT-PCR)-confirmed enterovirus (EV) meningitis without pleocytosis has only been previously reported in children. In this study, we examined the frequency of EV meningitis without pleocytosis in adults and compared its clinical features. We retrospectively analyzed the data of adult patients with EV meningitis confirmed using cerebrospinal fluid (CSF) RT-PCR. Among the 17 patients included in this study, 58.8% showed no pleocytosis. The median age and clinical symptoms did not differ between the pleocytosis and non-pleocytosis groups. There were no statistically significant differences in seasonal variation or time from the onset of meningitis symptoms to lumbar puncture. The peripheral white blood cell (WBC) count in patients with pleocytosis was significantly higher than that in patients without pleocytosis. The median CSF pressure showed a higher trend in the non-pleocytosis group. Patients with CSF pressures higher than normal were more common in the non-pleocytosis group. The median CSF protein values were higher than the normal values in both groups. We confirmed the high frequency of EV meningitis without pleocytosis in adults. Accurate diagnosis using RT-PCR is necessary when meningitis symptoms are prominent during an EV epidemic, and CSF protein levels and pressure are high, even if the CSF WBC count is normal.

Determining Normative Values for Cerebrospinal Fluid Profiles in Infants

BACKGROUND

Previous studies of reference values for cerebrospinal fluid (CSF) profiles have been limited by small sample size and few exclusion criteria.

OBJECTIVE

To determine age-specific normative CSF white blood cell count (WBC), glucose, and protein values in infants ≤90 days old.

METHODS

Performed a retrospective cross-sectional study of infants ≤90 days old who had a diagnostic lumbar puncture between 2008 and 2016. Infants with bacterial meningitis, bacteremia, UTI, positive CSF herpes simplex virus polymerase chain reaction (PCR) result, traumatic lumbar puncture, ventriculoperitoneal shunt, prematurity, recent seizure, previous antibiotic use, and history of a complex chronic condition were excluded for calculations to determine normative values. Data on demographics and CSF values (WBC with differential, protein, glucose, enterovirus PCR) were collected. CSF values were compared by age and by enterovirus PCR results using Kruskal-Wallis and Wilcoxon rank tests.

RESULTS

A total of 1029 out of 2000 patients were included and divided into 3 age groups: 0 to 28 days, 29 to 60 days, 61 to 90 days. CSF WBC values were significantly greater for 0- to 28-day old infants (median: 3, 95th percentile: 14) than for 29- to 60-day and 61- to 90-day old infants (median: 2 and 2; 95th percentile: 7 and 11, respectively) (P < .001). With each month of life, the median CSF protein significantly decreased and glucose significantly increased. In the CSF WBC differential, monocytes were found to be prevalent.

CONCLUSION

We determined age-specific normative components for CSF profile values for infants 0 to 90 days.

Bacterial Meningitis in the Absence of Pleocytosis in Children: A Systematic Review

One of the main features of bacterial meningitis is pleocytosis. However, when children with meningitis present within hours of onset of symptoms, there is the possibility that the meninges are not yet sufficiently inflamed to lead to a raised cerebrospinal fluid (CSF) white blood cell count. A systematic search was done to identify published studies reporting children with culture- or polymerase chain reaction-proven bacterial meningitis in the absence of pleocytosis. We identified 26 studies describing 62 children (18 neonates). In those in whom fever duration was specified, 32 (80%) of 40 had a fever for less than or equal to 24 hours before lumbar puncture (LP). In those in whom the glucose level was reported, it was normal in 14 (82%) of 17 neonates and 33 (80%) of 41 older infants and children. The protein level was normal in 8 (44%) of 17 neonates and 32 (80%) of 40 older infants and children. Twelve of the 62 children had a Gram stain of their CSF and this was positive in 2 (17%). Simultaneous blood cultures were positive in 5 (28%) of 18 neonates and 21 (68%) of 31 older infants and children. There was no association between the absence of pleocytosis and particular bacteria. All of the 10 children who had a second LP had an abnormal CSF including pleocytosis. These findings indicate that the absence of pleocytosis does not exclude bacterial meningitis reliably and should be interpreted in the context of the duration of illness. CSF samples, particularly those from cases with relatively short symptom duration, should be cultured even when the cell count and biochemistry are normal. A second LP can be helpful when bacterial meningitis is suspected despite a normal initial CSF.

The yield of CSF molecular testing in febrile neonates

We retrospectively examined the yield of a cerebrospinal fluid (CSF) multiplex real-time PCR assay of febrile young infants undergoing a full sepsis work-up. Eighty infants were included in the study: Forty-nine (61%) neonates and 31 (39%) 29-90 day-old patients were included in the study. A viral pathogen was detected in 59% (47/80) of the samples, human enterovirus in 53% (42/80) and Human parechovirus in 6% (5/80). The CSF of nearly half of the subjects with CNS infection was without pleocytosis; all CSF cultures were negative. Multiplex PCR CSF testing enhances the diagnosis of pathogen-specific viral CNS infection among febrile young infants.

Viral meningitis: an overview

Meningitis is a serious condition that affects the central nervous system. It is an inflammation of the meninges, which is the membrane that surrounds both the brain and the spinal cord. Meningitis can be caused by bacterial, viral, or fungal infections. Many viruses, such as enteroviruses, herpesviruses, and influenza viruses, can cause this neurological disorder. However, enteroviruses have been found to be the underlying cause of most viral meningitis cases worldwide. With few exceptions, the clinical manifestations and symptoms associated with viral meningitis are similar for the different causative agents, which makes it difficult to diagnose the disease at early stages. The pathogenesis of viral meningitis is not clearly defined, and more studies are needed to improve the health care of patients in terms of early diagnosis and management. This review article discusses the most common causative agents, epidemiology, clinical features, diagnosis, and pathogenesis of viral meningitis.

Novel scoring system for differentiating parechovirus-A3 and enterovirus infection in neonates and young infants

BACKGROUND

Parechovirus-A3 (PeV-A3) and the enteroviruses (EVs) are the most common viral pathogens responsible for sepsis and meningoencephalitis in neonates and young infants; however, differences in the clinical presentations of two infections are not well described.

OBJECTIVES

To describe the clinical presentations of PeV-A3- and EVs-related diseases and develop a novel scoring system to differentiate two diseases.

STUDY DESIGN

This prospective study used real-time PCR and genetic sequencing to evaluate viral etiologies of febrile neonates and infants <4 months with suspected sepsis or meningoencephalitis in Niigata area, Japan, in 2014-2016. The clinical manifestations of PeV-A3- and EVs-infected patients were compared, and a novel scoring system was developed after identifying the most distinguishable clinical findings, followed by the external cohort validation.

RESULTS

In 210 patients evaluated, we identified 56 PeV-A3-infected (27%) and 43 EVs-infected (20%) patients. The following clinical manifestations were significant in PeV-A3-infected patients, as compared with EVs-infected patients; a higher body temperature (38.9°C vs. 38.5°C, P < .01) and heart rate (181/min vs. 168/min, P = .01), cold extremities (72% vs. 34%, P < .01) and skin mottling (65% vs. 23%, P < .01), lower white blood cell count (5,200/μL vs. 8,900/μL, P < .01) and incidence of cerebrospinal fluid (CSF) pleocytosis (2% vs. 63%, P < .01). Using some of these significant findings, the scoring system successfully distinguished the diseases (accuracy: 86% and 83% for the derivative and external validation cohorts, respectively).

CONCLUSIONS

We found significant clinical manifestations in PeV-A3-infected patients compared to EVs-infected patients. The scoring system may be helpful to distinguish two infections, especially at onset of outbreak.

Clinical characteristics of enteroviral meningitis without pleocytosis in children: a retrospective single center observational study in the Republic of Korea

Background

We aimed to study the prevalence of enterovirus (EV) meningitis without the presence of cerebrospinal fluid (CSF) pleocytosis and identify patient factors and clinical features associated with it.

Methods

This was a retrospective analysis of patients aged < 18 years old who were diagnosed with EV meningitis by CSF reverse-transcriptase polymerase chain reaction (RT-PCR) testing between January 2015 and December 2016. Clinical variables were compared with regard to the presence of CSF pleocytosis.

Results

A total of 305 patients were enrolled in study; 169 (55.4%) had no pleocytosis. Patients without pleocytosis were younger (median age 2 months vs. 67.0 months, p < 0.01) and had lower white blood cell (WBC) count (median, 8600/mm³ vs. 10,300/mm³, p < 0.01). Also absolute neutrophil (ANC) count were lower than pleocytosis group (median, 4674/mm³ vs. 7600/mm³, p < 0.01). Comparing three age groups, CSF apleocytosis was present in 106 of 128 patients (82.8%) aged ≤3 months, 7 of 13 patients (53.8%) aged 3 months–3 years and 56 of 164 patients (34.1%) aged > 3 years. Younger age groups had higher prevalence of CSF apleocytosis (p < 0.01). In patients aged ≤3 months, 94.5% underwent lumbar puncture within 24 h of symptom onset. The frequency of not having pleocytosis was higher than the frequency of having pleocytosis during peak EV infection prevalent months (summer and fall) (p < 0.01).

Conclusion

This study shows that EV meningitis in young infants, with early lumbar puncture, or occurring during peak EV meningitis prevalent seasons cannot be solely excluded by pleocytosis. Also, a confirmation test for EV meningitis should be performed using RT-PCR.

Etiology and Clinical Features of Full-Term Neonatal Bacterial Meningitis: A Multicenter Retrospective Cohort Study

Objective: Neonatal bacterial meningitis is a severe infectious disease with a high risk of neurodevelopmental sequelae. The causative pathogens may be related to specific clinical features of the disease. Therefore, this study aimed at determining the pathogen-specific and clinical features of bacterial meningitis in full-term neonates. Methods: We enrolled neonates from the Shanghai Neonate Meningitis Cohort (2005-2017), which is a multicenter retrospective cohort that recruits almost all full-term neonates in Shanghai who underwent lumbar puncture. Patient history and clinical examination results were extracted from the computer-documented information systems of four hospitals. The trends of pathogen distribution were analyzed and differences in the clinical manifestations, treatment, and clinical outcomes at discharge were compared according to the causative pathogen. Logistic regression was used to evaluate the pathogen-specific risk of neurological complications. Results: In total, 518 cases of neonatal meningitis, including 189 proven cases, were included. Group B Streptococcus (GBS) and Escherichia coli (E. coli) were the leading pathogens in proven cases of early-onset and late-onset neonatal meningitis, respectively. The proportion of early-onset and late-onset GBS and late-onset E. coli meningitis cases increased gradually. GBS meningitis had the highest risk of neurological complications, whereas the overall incidence of hydrocephalus and brain abscess in E. coli was higher than that in GBS. Conclusions: Rates of neonatal GBS and E. coli meningitis were high in 2005-2017 in Shanghai, and the risk of neurological complications was also high. Therefore, active prevention, rational use of antibiotics, and continuous monitoring of GBS and E. coli in neonates should be initiated in Shanghai.

Enterovirus and parechovirus infections in children: differences in clinical presentation, mechanisms for meningitis without pleocytosis and mechanisms involved in the neurological outcome

Enterovirus (EV) and Parechovirus (HPeV) are a frequent cause of infection in children. This review gives an overview of possible causes for differences in clinical presentation. EV and HPeV can cause a meningitis with or without pleocytosis. Different possible mechanisms for meningitis without pleocytosis are given. Little is known about the prognosis and long-term effects of EV and HPeV meningitis in children. Only some studies with a small number of children with EV or HPeV meningitis are reported. The different possible mechanisms involved in the neurological outcome after EV or HPeV meningitis will be discussed.

Cerebrospinal fluid non-pleocytosis in pediatric enteroviral meningitis: Large-scale review

BACKGROUND

Lack of cerebrospinal fluid (CSF) pleocytosis has been reported in some children with enteroviral meningitis (EVM). The aim of this paper was to investigate the clinical spectrum and related factors in EVM with CSF non-pleocytosis.

METHODS

The databases of children diagnosed with EVM on CSF polymerase chain reaction between 2011 and 2014 were retrospectively reviewed. CSF pleocytosis was defined at each age using the criteria. Clinical and laboratory variables were compared between patients with CSF pleocytosis and non-pleocytosis.

RESULTS

Of the 802 children of EVM, 25.4% (204/802) had CSF non-pleocytosis. In particular, CSF non-pleocytosis was found in 63.3% of the neonates versus in 22.2% of the children aged ≥1 year old, indicating that the ratio of CSF non-pleocytosis had a negative correlation with age (P < 0.001). As the main symptoms, fever (91.8% vs 86.8%, P = 0.038), headache (80.3% vs 63.7%, P < 0.001), and vomiting (75.9% vs 61.8%, P < 0.001) were significantly more frequent in CSF pleocytosis than in CSF non-pleocytosis. Patients with CSF non-pleocytosis had much lower peripheral leukocytosis (10 656 ± 3,662 vs 12 403 ± 4,207/mm³ , P = 0.014) and C-reactive protein (0.7±0.8 vs 1.2±1.5 mg/dL, P < 0.001), and earlier lumbar puncture <24 h after onset (42.6% vs 21.4%, p<0.001). No significant difference during the summer and autumn months was seen between the two groups (76.9% vs 81.9%, P = 0.169).

CONCLUSION

CSF non-pleocytosis in childhood EVM was frequently observed, especially in young infants, regardless of season. We propose that CSF PCR testing for enterovirus can be helpful to recognize EVM in children with CSF non-pleocytosis.

Comparison of Cerebrospinal Fluid Cytokine Levels in Children of Enteroviral Meningitis With Versus Without Pleocytosis

In viral meningitis, proinflammatory cytokines were detected at higher levels in the cerebrospinal fluid (CSF) and might play an important role in the inflammatory process. Our goal was to compare the cytokine profiles in the CSF of children of enteroviral meningitis (EVM) with versus without CSF pleocytosis. In total, 158 patients were enrolled in this prospective cohort study and were classified as EVM (group-A, n = 101), nonenteroviral aseptic meningitis (group-B, n = 27), and control (group-C, n = 30) groups. Of the 101 children with EVM, 71 had CSF pleocytosis (group-A1) and 30 had CSF nonpleocytosis (group-A2). Fifteen cytokines/chemokines in the CSF were measured simultaneously by immunoassay. Significant differences were found in interleukin (IL)-2, IL-6, and IL-8 levels in the CSF across the 3 groups, with the highest levels in group-A, followed by group-B and group-C. The levels of IL-1β, IL-2, IL-6, IL8, IL-10, interferon-γ, and tumor necrosis factor-α were significantly higher in the CSF of group-A1 than in that of group-A2. Group-A2 was significantly younger than group-A1 (3.4 ± 2.8 years versus 5.5 ± 3.2 years, P = 0.016). Significant differences between CSF pleocytosis and nonpleocytosis in EVM appear to be associated with distinct levels of CSF cytokines.

Encephalitis in US Children

Encephalitis is an uncommon but severe disease characterized by neurologic dysfunction with central nervous system inflammation. Children with encephalitis should receive supportive care and empiric therapies for common and treatable causes while prioritizing diagnostic evaluation for common, treatable, and high-risk conditions. Even with an extensive diagnostic workup, an infectious cause is identified in less than half of cases, suggesting a role for postinfectious or noninfectious processes.

Cerebrospinal Fluid Reference Values for Young Infants Undergoing Lumbar Puncture

OBJECTIVES

To determine age-specific reference values and quantify age-related changes for cerebrospinal fluid (CSF) white blood cell (WBC) counts and protein and glucose concentrations in infants ≤60 days of age.

METHODS

This multicenter, cross-sectional study included infants ≤60 days old with CSF cultures and complete CSF profiles obtained within 24 hours of presentation. Those with conditions suspected or known to cause abnormal CSF parameters (eg, meningitis) and those with a hospital length of stay of >72 hours were excluded. Reference standards were determined for infants ≤28 days of age and 29 to 60 days of age by using the third quartile +1.5 interquartile range for WBC and protein and the first quartile -1.5 interquartile range for glucose. CSF parameter centile curves based on age were calculated by using the LMST method.

RESULTS

A total of 7766 patients were included. CSF WBC counts were higher in infants ≤28 days of age (upper bound: 15 cells/mm³) than in infants 29 to 60 days of age (upper bound: 9 cells/mm³; P < .001). CSF protein concentrations were higher in infants ≤28 days of age (upper bound: 127 mg/dL) than in infants 29 to 60 days of age (upper bound: 99 mg/dL; P < .001). CSF glucose concentrations were lower in infants ≤28 days of age (lower bound: 25 mg/dL) than in infants 29 to 60 days of age (lower bound: 27 mg/dL; P < .001).

CONCLUSIONS

The age-specific CSF WBC count, protein concentration, and glucose concentration reference values identified in this large, multicenter cohort of infants can be used to interpret the results of lumbar puncture in infants ≤60 days of age.

Outpatient management of selected young febrile infants without antibiotics

OBJECTIVE

To analyse the outpatient management of selected febrile infants younger than 90 days without systematic lumbar puncture and antibiotics.

METHODS

A prospective registry-based cohort study including all the infants ≤90 days with fever without a source (FWS) who were evaluated in a paediatric emergency department (ED) over a 7-year period (September 2007-August 2014). We analysed the outcome of those infants with low-risk criteria for serious bacterial infection (SBI) managed as outpatients without antibiotics and without undergoing a lumbar puncture. Low-risk criteria: Well appearing, older than 21 days of age, no leucocyturia, absolute neutrophil count ≤10 000, serum C reactive protein ≤20 mg/L, procalcitonin <0.5 ng/mL and no clinical deterioration during the stay in the ED (always <24 hours).

RESULTS

1472 infants with FWS attended the ED. Of these, 676 were classified to be at low risk for SBI without performing a lumbar puncture. After staying <24 hours in the short-stay unit of the ED, 586 (86.6%) were managed as outpatients without antibiotics. Two patients were diagnosed with SBI: one occult bacteraemia and one bacterial gastroenteritis. Both were afebrile when evaluated again and did well. No patient returned to the ED due to clinical deterioration. Fifty-one infants (8.7%) returned to the ED mainly due to persistence of fever or irritability. None was diagnosed with definite SBI or non-bacterial meningitis.

CONCLUSIONS

Outpatient management without antibiotics and systematic lumbar puncture is appropriate for selected febrile infants younger than 3 months of age with close follow-up.

Molecular detection and genotyping of enteroviruses from CSF samples of patients with suspected sepsis-like illness and/or aseptic meningitis from 2012 to 2015 in West Bank, Palestine

BACKGROUND

Human enteroviruses (HEVs) are the most frequently reported cause of aseptic meningitis with or without CSF pleocytosis in childhood. Rapid detection and genotype of HEVs is essential to determine the causative agent and variant causing sepsis-like illness and/or aseptic meningitis.

AIM

To investigate the molecular epidemiology of enteroviruses (EVs) among patients with sepsis-like illness and/or aseptic meningitis admitted to three major hospitals in West Bank, Palestine from 2012 to 2015.

METHODS

During the study period, 356 CSF samples were collected from patients with sepsis-like illness and/or aseptic meningitis. Two RT-nested PCR assays targeting a partial part of 5'UTR for direct diagnosis and the VP1 region for genotyping by sequence analysis of the viral genome were used.

RESULTS

HEV RNA was detected in 66 of 356 (18.5%) of CSF samples. Age distribution showed that 64% (42/66) were infants (<1 year), 18% were children between 1 and 5 years old, 12% were children between 5 and 10 years old, and 6% were more than 10 years old. Of the 66 EV cases, 12 were successfully genotyped. Five different EV genotypes were identified. All of them belonged to HEV-B species. The study showed that echovirus 6 genotype accounted for 42% of the sequenced cases. The HEV infections in the present study tended to show slight seasonal pattern with more cases occurring during spring and summer, yet still significant numbers were also reported in fall and winter seasons.

CONCLUSION

HEV was isolated from a significant number of children with sepsis-like illness and/or aseptic meningitis. In addition, the molecular method utilized for direct diagnosis and genotyping of HEV from CSF revealed that more than one HEV type circulated in the West Bank, Palestine during the study period.

Impact of Enterovirus Testing on Resource Use in Febrile Young Infants: A Systematic Review

CONTEXT

Enterovirus infection commonly causes fever in infants aged 0 to 90 days and, without testing, is difficult to differentiate from serious bacterial infection.

OBJECTIVE

To determine the cost savings of routine enterovirus testing and identify subgroups of infants with greater potential impact from testing among infants 0 to 90 days old with fever.

DATA SOURCES

Studies were identified systematically from published and unpublished literature by using Embase, Medline, the Cochrane database, and conference proceedings.

STUDY SELECTION

Inclusion criteria were original studies, in any language, of enterovirus infection including the outcomes of interest in infants aged 0 to 90 days.

DATA EXTRACTION

Standardized instruments were used to appraise each study. The evidence quality was evaluated using Grading of Recommendations Assessment, Development, and Evaluation criteria. Two investigators independently searched the literature, screened and critically appraised the studies, extracted the data, and applied the Grading of Recommendations Assessment, Development, and Evaluation criteria.

RESULTS

Of the 257 unique studies identified and screened, 32 were completely reviewed and 8 were included. Routine enterovirus testing was associated with reduced hospital length of stay and cost savings during peak enterovirus season. Cerebrospinal fluid pleocytosis was a poor predictor of enterovirus meningitis. The studies were all observational and the evidence was of low quality.

CONCLUSIONS

Enterovirus polymerase chain reaction testing, independent of cerebrospinal fluid pleocytosis, can reduce length of stay and achieve cost savings, especially during times of high enterovirus prevalence. Additional study is needed to identify subgroups that may achieve greater cost savings from testing to additionally enhance the efficiency of testing.

Delayed Diagnosis of Tuberculous Meningitis Misdiagnosed as Herpes Simplex Virus-1 Encephalitis With the FilmArray Syndromic Polymerase Chain Reaction Panel

The FilmArray meningitis/encephalitis (ME) panel is a novel syndromic, nucleic acid amplification test for diagnosis of acute meningitis and encephalitis. Emerging data on its performance are concerning for false-positive results. We present a case of tuberculous meningitis misdiagnosed as herpes simplex virus-1 encephalitis with the FilmArray ME panel. Strategies to mitigate erroneous results are discussed.

Enteroviral Meningitis in Neonates and Children of Mashhad, Iran

Background

The highest incidence of meningitis occurs during the neonatal period and (then) infancy. Although Bacterial agents are the most dangerous cause of neonatal and childhood meningitis yet viruses especially, enteroviruses (EV), are by far the most common cause of meningitis in this age group.

Objectives

The aim of the current study was to evaluate the role of EVs in neonatal and childhood meningitis in the Mashhad city of Iran.

Materials and Methods

This was a descriptive study that was performed at Imam Reza hospital in a period of six months (March to September 2007), during which all of the cerebral spinal fluid (CSF) samples from the neonatal intensive care unit (NICU) and pediatrics ward were collected and real time-polymerase chain reaction (RT-PCR) for EVs was done on these samples. Clinical data were collected retrospectively from hospital files.

Results

We collected 58 CSF samples (35 neonates and 23 children) during six months. Pleocytosis of CSF was seen in 51.1% of the subjects (28% of neonates, and 66.6% of infants and children). Enteroviruses PCR was positive in 37.1% (13) of neonates and 34.7% (8) of children. Pleocytosis of CSF was seen in 23% and 75% of EV positive neonates and children, respectively. Polymorphonuclear (PMN) dominance (PMN > 50%) of CSF was seen in 50% and 33% of EV positive neonates and children, respectively. There were three cases of bacterial meningitis in our group; EV PCR result was positive for one of these subjects. Concomitant bacterial infection (meningitis and sepsis) was seen in 9.5% (two cases) of EV positive CSFs in our study. Almost half of the available neonates (four of nine) with pure enteroviral meningitis (EVM) were discharged (in good condition) with final diagnosis of culture negative sepsis (CNS) and mean length of hospital stay (MLOS) of 4.3 days. One (12.5%) of the neonates with EVM, who had a very low birth weight (< 1500 mg), was expired, and two (25%) cases were discharged with brain damage and final diagnosis of severe asphyxia. The MLOS for children with pure EVM was 1.6 days (one to four days); they didn't have any sign of brain damage or mortality. Qualitative c-reactive protein (CRP) of serum was negative in 72.7% and 37.5% of EV positive neonates and children, respectively. The mean white blood cell count and PMN percentage in the peripheral blood was 11416/mm³ and 60.8% for EV positive neonates, and 14500/mm³ and 77.1% for EV positive children, respectively. Hyponatremia, due to possible syndrome of inappropriate antidiuretic hormone (SIADH), was seen in 30% of neonates and 57% of children with EVM.

Conclusions

Enteroviruses were a common cause (> 30%) of meningitis in our study group. Concomitant bacterial infection is not rare in neonates and children with EVM. Many of the neonates (50%) and almost all of the children with EVM did not require prolonged hospitalization. Both normal CSF and PMN dominancy of CSF was common in neonates and children with EVM. Positive qualitative CRP of serum (up to two plus) was common especially in children with EVM. Non-symptomatic mild hyponatremia/SIADH was common in early life EVM.

Developmental outcomes in cerebrospinal fluid proven enteroviral meningitis in neonates > 32 weeks of gestation

AIM

The aim of this study is to assess the short-term and long-term (1 year) outcomes of cerebrospinal fluid (CSF) confirmed enteroviral meningitis in neonates > 32 weeks of gestation.

METHODS

A retrospective audit of neonates admitted between 1 July 2002 to 30 June 2012.

RESULTS

Thirty-three neonates were diagnosed with enteroviral meningitis based on a positive CSF enteroviral PCR. Physical growth and neurodevelopmental outcomes at 1 year corrected for prematurity were available for 24 infants. All infants were alive at 1 year. The median weight, length and head circumference at 1 year were in the 72nd, 62nd and 78th centile and were comparable with the birth parameters. The mean general quotient (GQ) was 98.5 (SD 7.1) and was not significantly different from the population mean of 100.2 (P = 0.27). None of the infants had a GQ > 2SD below the population mean. Neurological recovery was complete in the 24 neonates assessed except one, who developed cerebral palsy, epilepsy and progressive hydrocephalus requiring ventriculoperitoneal shunt at 1 year.

CONCLUSION

Neonatal enteroviral meningitis was associated with optimal growth and neurodevelopment in the majority of the infants at 1 year corrected for prematurity. Longer term studies are needed to better define developmental outcomes.

Human Parechovirus 3: The Most Common Viral Cause of Meningoencephalitis in Young Infants

Human parechoviruses (HPeVs) were initially classified as echoviruses. HPeVs occur worldwide, comprising up to 17 genotypes. HPeV1 and HPeV3 are most common. Clinical disease varies somewhat among genotypes. HPeV1 causes mostly gastrointestinal infections. HPeV3's prominence is due to its causing sepsis syndromes and central nervous system (CNS) infections in young infants. Currently, HPeV3 is the most common single cause of aseptic meningitis/meningoencephalitis in infants less than 90 days old in North America, usually with biannual summer-fall seasonality. HPeV3 CNS infections usually lack cerebrospinal fluid pleocytosis. Mortality and sequelae are uncommon, usually accompanying initially severe or neurologically complicated acute illnesses.

Prevalence of human parechovirus and enterovirus in cerebrospinal fluid samples in children in Jinju, Korea

Purpose

Human parechovirus (HPeV) and enterovirus (EV) are causative agents of a sepsis-like illness in neonates and of infections of the central nervous system in young children. The objectives of this study were to assess the prevalence of HPeV3 and EV infection in young children with a sepsis-like illness or with meningitis in Jinju, Korea.

Methods

Cerebrospinal fluid (CSF) samples were collected from 267 patients (age range, 1 day to 5 years) and assessed for HPeV and EV by performing reverse transcription polymerase chain reaction assay. Amplification products of the VP3/VP1 region of HPeV and of the VP1 region of EV were sequenced to identify the virus type.

Results

HPeV and EV were detected in 3.4% and 7.5% of the total CSF samples assessed, respectively. The age distribution of EV-positive patients (median age, 1.4 months) had a significantly broader range than that of HPeV-positive patients (median age, 7.8 months). The peak seasons for HPeV and EV infection were spring and summer, respectively. The clinical symptoms for HPeV and EV infection were similar, and fever was the most common symptom. Pleocytosis was detected in 22.2% of HPeV-positive patients and 35.5% of EV-positive patients. The VP3/VP1 gene sequence of the nine Korean strains clustered most closely with the Japanese strain (AB759202).

Conclusion

The data indicate that HPeV infection is predominant in young infants (<6 months) and that meningitis without pleocytosis was caused by both HPeV and EV infection in children.

Relevance of human parechovirus detection in cerebrospinal fluid samples from young infants with sepsis-like illness

BACKGROUND

The human parechoviruses (HPeVs) were recently recognized as important viral pathogens involved in various illnesses in young children. However, routine detection is not performed in most clinical laboratories. Therefore, in this study, we aim to assess the relevance of HPeV detection in cerebrospinal fluid (CSF) of infants, according to clinical presentation.

METHODS

A total of 120 CSF specimens collected during 2012 from infants aged less than 1 year and previously reported negative for Herpes simplex virus (HSV) and enterovirus were selected. HPeV detection was performed with a commercially available real-time RT-PCR and HPeV strains from positive samples were subsequently genotyped by sequencing.

RESULTS

HPeV RNA was detected in nine (7.5%) CSF samples. The median age of infected children was 41 days (range: 19-122 days). HPeV genotyping could be performed on five samples and three HPeV-3, one HPeV-1, and one HPeV-4 were identified. Hyperthermia associated with mottled skin was the predominant clinical presentation. Most clinical presentations of HPeV-infected infants were mild with a final diagnosis of sepsis-like illness. The median hospital stay was 3.5 days and five children received antibiotics.

CONCLUSION

Routine detection of HPeV in CSF may allow differential diagnosis of enterovirus infection and improve etiologic identification of sepsis-like illness in children.

Enterovirus reverse transcriptase polymerase chain reaction assay in cerebrospinal fluid: an essential tool in meningitis management in childhood

BACKGROUND

Enteroviruses (EV) are the main aetiological agents of aseptic meningitis in children and a common cause of febrile illnesses in young infants in summer. A rapid diagnosis is essential to rule out other conditions. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay performed in cerebrospinal fluid (CSF) has proved to be a very fast and useful tool.

METHODS

We collected demographic, clinical and laboratory data of children (aged 11-years or younger) with EV RT-PCR (Cepheid(®) Xpert EV) positive in CSF from December 2007 to July 2010, to describe EV meningitis in children and to determine the role of this assay.

RESULTS

We included 92 children (mean age 2.5 years), 32% of whom were neonates. There was no pleocytosis in the CSF of 18.5% (36% in newborn) of the patients, and 23 (25%) were discharged to home from the Emergency Room after the positive results. Length of hospital stay was 2 days (>2 years) versus 4.5 days in newborns (P<0.0001). Antibiotic treatment was prescribed in 38% (75% <3 months), but in 40% of these, it was stopped after the positive results. Mean EV RT-PCR information time was 7h (4-18h). All children had a good clinical outcome.

CONCLUSIONS

EV RT-PCR assay in CSF has played an essential role in the management of children with EV meningitis, allowing earlier discharges and decreasing avoidable inappropriate antibiotic treatments. This test should be considered as part of the initial study of children with aseptic meningitis, especially during epidemic seasons.

Lumbar puncture in the neonate: challenges in decision making and interpretation

Multiple studies have provided normative ranges for cerebrospinal fluid (CSF) parameters in term and preterm infants and described changes with advancing postnatal age, as well as in special circumstances, such as traumatic lumbar puncture (LP), previous antibiotic administration, seizures, and concomitant infections at other sites. Although guidelines exist for the interpretation of CSF parameters in neonates, there appears to be no single combination of parameters that conclusively excludes meningitis. It remains important for clinicians to perform LPs early in the course of illness, ideally before the administration of antibiotic therapy. This review presents currently available literature on the indications for LP as well as guidelines for the interpretation of CSF parameters in neonates.

Clinical and analytical characteristics and short-term evolution of enteroviral meningitis in young infants presenting with fever without source

OBJECTIVE

The objective of this study was to describe the characteristics of the enteroviral meningitis diagnosed in a pediatric emergency department among infants younger than 3 months with fever without source and its short-term evolution.

METHODS

This was a retrospective, cross-sectional, 6-year descriptive study including all infants younger than 3 months who presented with fever without source and who were diagnosed with enteroviral meningitis.

RESULTS

A lumbar puncture was practiced at their first emergency visit in 398 (29.5%) of 1348 infants, and 65 (4.8%) were diagnosed with enteroviral meningitis, 33 of them (50.7%) between May and July. Among these 65 infants, 61 were classified as well-appearing; parents referred irritability in 16 (25.3%) of them (without statistical significance when compared with infants without meningitis). Forty-one (63.0%) had no altered infectious parameters (white blood cell [WBC] count between 5000 and 15,000/μL, absolute neutrophil count less than 10,000/μL, and C-reactive protein less than 20 g/L), and 39 (60%) had no pleocytosis. All of the 65 infants recovered well, and none of them developed short-term complications.

CONCLUSIONS

The symptoms in infants younger than 3 months with enteroviral meningitis were similar to those in infants with a self-limited febrile process without intracranial infection. C-reactive protein and WBC count were not good enteroviral meningitis predictors. Cerebrospinal fluid WBC count was normal in many of these infants, so performing a viral test is recommended for febrile infants younger than 3 months in which a lumbar puncture is practiced during warm months. The short-term evolution was benign.

Characteristics of pediatric patients with enterovirus meningitis and no cerebral fluid pleocytosis

Human non-polio enterovirus (EV) is the most important cause of aseptic meningitis in children. Only a few studies report the lack of cerobrospinal fluid (CSF) pleocytosis in children with confirmed EV meningitis; however, the characteristics of these children have not been well defined. This paper describes the clinical and laboratory features of EV meningitis in children with no CSF pleocytosis. Clinical, laboratory, and virological data of Dutch patients <16 years diagnosed with EV meningitis, between 2003 and 2008, were analyzed retrospectively. Data of children with and without CSF pleocytosis were compared. A total of 149 children were infected with EV. Patients presented mainly with fever (n = 113), malaise (n = 43), abdominal pain (n = 47), and irritability (n = 61). Of the 60 patients with EV meningitis, 23 had no pleocytosis. Those who lacked CSF pleocytosis were younger [odds ratio (OR) 1.00; 95% confidence interval (CI) 1.000-1.002; p = 0.001], had experienced drowsiness more (OR 9.60; 95% CI 2.24-41.15; p = 0.002), had lower white blood cell counts (OR 0.73; 95% CI 0.61-0.89; p = 0.001), and had higher C-reactive protein (OR 1.13; 95% CI 1.03-1.23; p = 0.006) than those with pleocytosis.

CONCLUSION

These findings show that EV meningitis occurs in the absence of CSF pleocytosis, particularly in young infants, meaning that EV meningitis in this age group cannot be solely excluded by the absence of CSF pleocytosis. They also confirm the importance of genome detection in the diagnosis of EV meningitis in young infants.

Low prevalence of invasive bacterial infection in febrile infants under 3 months of age with enterovirus infection

Infants under 3 months of age with fever without source (FWS) generally undergo a full, invasive septic evaluation to exclude invasive bacterial infection (IBI). Enterovirus (EV) infections are mostly banal and self-limiting and show a high prevalence rate at this age. We aimed to investigate the prevalence of IBI in EV-infected and uninfected infants under 3 months of age with FWS. This was a prospective observational cohort study of infants aged <90 days who were admitted because of FWS. As per protocol, blood and urine analysis and culture were obtained in all cases, and RNA EV from blood and/or cerebrospinal fluid samples was determined by real-time PCR. Three hundred and eighty-one previously healthy infants with FWS were included. EV infection was diagnosed in 64 children (16.8%; 95% confidence interval, 13.2-20.9%) and showed an uneventful evolution in all cases. Laboratory markers of infection were consistently lower in EV-infected patients; only one case of IBI (1.6%) was observed in an EV-infected patient as compared with 25.2% in EV-negative infants (p <0.001). Intravenous antibiotic use and length of stay were no different in EV-infected and uninfected patients. In our study, febrile infants (<90 days) diagnosed with EV infection showed a low risk of IBI when compared with uninfected patients. The systematic investigation of EV infection in young infants with FWS may allow a more conservative approach to the management of these patients. Further studies on this diagnostic approach are needed.

Human parechovirus 3 causing sepsis-like illness in children from midwestern United States

BACKGROUND

: Human parechovirus (HPeV) infections of the central nervous system (CNS) in children can be associated with severe outcomes such as neonatal sepsis-like illness, meningitis, or paralysis. We sought to determine the prevalence of HPeV CNS infections and clinical presentation in children from the United States.

METHODS

: Frozen nucleic acid extracts from enterovirus-negative cerebrospinal fluid (CSF) obtained at the Children's Mercy Hospitals and Clinics, in Kansas City from 2006 (n = 242), 2007 (n = 324), and 2008 (n = 218) were tested by 2-step HPeV real-time reverse transcription polymerase chain reaction. HPeV genotype was determined by sequencing the VP3/VP1 junction. Demographic and clinical data were abstracted from medical records.

RESULTS

: Overall HPeV was detected in 58/780 (7%) of tested CSF samples; 4/218 (2%) in 2006, 54/320 (17%) in 2007, and 0/242 (0%) in 2008. HPeV (17%) and enterovirus (20%) detection were comparable in 2007. HPeV-3 genotype was detected in 52/53 specimens successfully sequenced. Detection was seasonal (June-October). HPeV-3-CNS-infection occurred at a mean age of 6.6 ± 4.4 weeks and predominantly in males (71%). The most common clinical presentation was sepsis-like syndrome (66%). The most common symptoms were irritability (98%), fever (95%), and nonspecific rash (58.6%), while neurologic manifestations were rare (5%).

CONCLUSIONS

: To our knowledge, this is the first multiyear prevalence report of HPeV CNS infection in the United States. HPeV CNS infection was detected mostly in male infants with sepsis-like illness during the late summer/autumn season. Routine seasonal CSF testing in infants for HPeV plus enterovirus may improve etiologic detection and clinical management of infantile sepsis-like presentations.

Age-specific reference values for cerebrospinal fluid protein concentration in neonates and young infants

BACKGROUND

Cerebrospinal fluid (CSF) protein values decline over the first few months of life as the infant's blood-CSF barrier matures. However, published studies differ in the reported rate, timing, and magnitude of this decline.

OBJECTIVE

To quantify the age-related changes in CSF protein concentration and to determine accurate, age-specific reference values for neonates and young infants.

DESIGN, SETTING AND PATIENTS

This cross-sectional study included infants age 56 days or younger who had a lumbar puncture performed in the emergency department of an urban tertiary care children's hospital between January 1, 2005 and June 30, 2007. Infants with conditions associated with elevated CSF protein concentrations, including traumatic lumbar puncture and bacterial or viral meningitis, were excluded.

RESULTS

Of 1064 infants undergoing lumbar puncture, 375 (35%) met inclusion criteria. The median CSF protein value was 58 mg/dL (interquartile range: 48-72 mg/dL). In linear regression, the CSF protein concentration decreased 6.8% (95% confidence interval [CI], 5.4%-8.1%; P < 0.001) with each 1 week increase in age. The 95th percentile values were 115 mg/dL for infants ≤28 days and 89 mg/dL for infants 29-56 days. The 95th percentile values by age category were as follows: ages 0-14 days, 132 mg/dL; ages 15-28 days, 100 mg/dL; ages 29-42 days, 89 mg/dL; and ages 43-56 days, 83 mg/dL.

CONCLUSIONS

We quantify the age-related decline in CSF protein concentration among infants 56 days of age and younger and provide age-specific reference values. The values reported here represent the largest series to-date for this age group.