West Nile virus (WNV) is a single-stranded RNA virus causing a wide spectrum of diseases. Neuroinvasive conditions such as meningitis and encephalitis are feared complications of WNV infection. Here, we describe the case of a 78-year-old male whose only initial presenting symptoms were fever and transient diplopia, whose initial MRI imaging with and without contrast did not reveal any abnormalities. He was discharged, only to return to care the next day; lumbar puncture was performed suggesting bacterial meningitis, and he was admitted and given antibiotics. Repeat MRI was negative, and he developed an altered mental status requiring intubation. WNV neuroinvasive disease was subsequently found after serology was performed. Supportive care was given, and he made a full recovery with no residual deficits. This case highlights an unusual presentation of WNV encephalitis and highlights the difficulty that can be present in diagnosing this disease.

BACKGROUND: Herpes zoster is an infectious skin disease caused by the reactivation of the varicella zoster virus (VZV), which has been latent in the posterior root ganglia of the spinal cord or cranial ganglia for an extended period. Neurological complications caused by herpes zoster include aseptic meningitis, white matter disease, peripheral motor neuropathy, and Guillain-Barré syndrome. However, reduced unilateral sweating caused by the VZV is very rare.
METHODS: This article reports the case of a 34-year-old woman who was admitted to our hospital with sore throat, dizziness, and reduced sweating on the left side of her body. Physical examination found herpes lesions on the left upper lip and left external ear canal (scabbed) and reduced sweating on the left side of the body. Head magnetic resonance imaging (MRI) with contrast showed no abnormalities. After a lumbar puncture, the patient was diagnosed with viral meningitis by VZV infection. The electromyographic skin sympathetic reflex indicated damage to the left sympathetic nerve.
CONCLUSIONS: Secondary unilateral sweating reduction is a rare neurological complication of herpes zoster, caused by damage to the autonomic nervous system. Literature review and comprehensive examination indicated that the reduced unilateral sweating was due to the activation of latent herpes zoster virus in the autonomic ganglia which has damaged the autonomic nervous system. For patients who exhibit acute hemibody sweat reduction, doctors should consider the possibility of secondary autonomic nervous system damage caused by herpes zoster.

The extracellular matrix protein tenascin-C has been discovered to be an important regulator of the response to tissue injury and repair in cerebrovascular diseases. This study investigated if tenascin-C is released in response to infections in the central nervous system (CNS).
Tenascin-C concentration in the cerebrospinal fluid (CSF) was measured in patients, (>18 years) with and without CNS infections, admitted to a department of infectious diseases in Denmark. CSF tenascin-C was measured on the Meso-scale platform.
174 patients were included of which 140 were diagnosed with a CNS infection and 34 where this was ruled out (control group). Median CSF tenascin-C levels were significantly higher among patients with bacterial meningitis (147 pg/mL), viral meningitis (33 mg/mL), viral encephalitis (39 pg/mL) and Lyme neuroborreliosis (45 pg/mL) when compared to controls (21 pg/mL). Correlations between tenascin-C and CSF markers of inflammation and age were only moderate.
Levels of CSF tenascin-C are higher among patients with bacterial and viral neuroinfections, already on admission, but exhibit only a modest correlation with baseline indices of neuroinflammation. CSF tenascin-C is highest among patients with bacterial meningitis compared to the other CNS infections. Patients with unfavorable outcomes presented with higher median CSF tenascin-C than their counterparts.

UNASSIGNED: Acute meningitis is a disease with case fatality and disability rate that is dependent on the causative agent.
UNASSIGNED: Determine the meningitis trend in Iraq from 2007 to 2023 using a joinpoint regression at national and sub-national levels and describe the epidemiology.
UNASSIGNED: Joinpoint regression model was used on surveillance data from Jan 2007 until May 2023, to calculate annual and average annual percent changes to determine the trend. Meningitis total count was modelled by year of reporting and province using the log transformation and Poisson variance. Best-fit model was chosen based on the weighted BIC criteria as the final point.
UNASSIGNED: Bacterial meningitis was higher than viral meningitis from 2007 to 2018, then viral meningitis started to exceed till 2023. Meningococcal meningitis was lower than other bacterial and viral meningitis from 2007 to 2023. Most meningitis cases across the years were lower than 15 years, at almost 80 %, while 20 %-40 % were lower than one year. Across all years, 55 % of the cases were males; apart from 2019, 70 % were females.
UNASSIGNED: In Iraq, viral meningitis has been the predominant type since 2018. Most meningitis patients were lower than 15-year-old males. The meningitis trend in Iraq was stable from 2007 till 2023.

Objective The changes in the prevalence of acute meningitis during the coronavirus disease 2019 (COVID-19) pandemic remain unclear. This study aimed to compare the prevalence of acute meningitis before and during the COVID-19 pandemic in Japan. Methods We retrospectively reviewed the Japanese nationwide administrative medical payment system database, Diagnosis Procedure Combination (DPC), from 2016 to 2022. A total of 547 hospitals consistently and seamlessly offered DPC data during this period. The study period was divided into the following three periods: April 2016 to March 2018 (fiscal years 2016-2017), April 2018-March 2020 (2018-2019), and April 2020-March 2022 (2020-2021). Results Among the 28,161,806 patients hospitalized during the study period, 28,399 were hospitalized for acute meningitis: 16,678 for viral/aseptic type, 6,189 for bacterial type, 655 for fungal type, 429 for tuberculous, 2,310 for carcinomatous type, and 2,138 for other or unknown types of meningitis. A significant decrease during the pandemic was confirmed in viral (n=7,032, n=5,775, and n=3,871 in each period; p<0.0001) and bacterial meningitis (n=2,291, n=2,239, and n=1,659; p<0.0001) cases. Meanwhile, no decrease was observed in fungal meningitis (n=212, n=246, and n=197; p=0.056) or carcinomatous meningitis (n=781, n=795, and n=734; p=0.27). The decrease in the number of tuberculous meningitis cases was equivocal (n=166, n=146, and n=117; p=0.014). The decrease during the pandemic was more remarkable in younger populations aged <50 years than in older populations, both for viral and bacterial meningitis. Conclusion The number of hospitalized cases of acute meningitis clearly decreased during the COVID-19 pandemic, especially for viral and bacterial meningitis in younger populations aged <50 years.

BACKGROUND: Interpretation of cerebrospinal fluid (CSF) studies can be challenging in preterm infants. We hypothesized that intraventricular hemorrhage (IVH), post-hemorrhagic hydrocephalus (PHH), and infection (meningitis) promote pro-inflammatory CSF conditions reflected in CSF parameters.
METHODS: Biochemical and cytological profiles of lumbar CSF and peripheral blood samples were analyzed for 81 control, 29 IVH grade 1/2 (IVH1/2), 13 IVH grade 3/4 (IVH3/4), 15 PHH, 20 culture-confirmed bacterial meningitis (BM), and 27 viral meningitis (VM) infants at 36.5 ± 4 weeks estimated gestational age.
RESULTS: PHH infants had higher (p < 0.02) CSF total cell and red blood cell (RBC) counts compared to control, IVH1/2, BM, and VM infants. No differences in white blood cell (WBC) count were found between IVH3/4, PHH, BM, and VM infants. CSF neutrophil counts increased (p ≤ 0.03) for all groups compared to controls except IVH1/2. CSF protein levels were higher (p ≤ 0.02) and CSF glucose levels were lower (p ≤ 0.003) for PHH infants compared to all other groups. In peripheral blood, PHH infants had higher (p ≤ 0.001) WBC counts and lower (p ≤ 0.03) hemoglobin and hematocrit than all groups except for IVH3/4.
CONCLUSIONS: Similarities in CSF parameters may reflect common pathological processes in the inflammatory response and show the complexity associated with interpreting CSF profiles, especially in PHH and meningitis/ventriculitis.

Human enteroviruses (EV) are the most common cause of aseptic meningitis worldwide. Data on EV viral load in cerebrospinal fluid (CSF) and related epidemiological studies are scarce in Brazil. This study investigated the influence of EV viral load on CSF parameters, as well as identifying the involved species. CSF samples were collected in 2018-2019 from 140 individuals at The Hospital das Clínicas, São Paulo. The EV viral load was determined using real-time quantitative polymerase chain reaction, while EV species were identified by 5\'UTR region sequencing. Median viral load was 5.72 log10  copies/mL and did not differ by subjects\' age and EV species. Pleocytosis was observed in 94.3% of cases, with the highest white blood cell (WBC) counts in younger individuals. Viral load and WBC count were correlated in children (p = 0.0172). Elevated lactate levels were observed in 60% of cases and correlated with the viral load in preteen-teenagers (p = 0.0120) and adults (p = 0.0184). Most individuals had normal total protein levels (70.7%), with higher in preteen-teenagers and adults (p < 0.0001). By sequencing, 8.2% were identified as EV species A and 91.8% as species B. Age-specific variations in CSF characteristics suggest distinct inflammatory responses in each group.

BACKGROUND: We aimed to investigate the involvement of long non-coding RNA (lncRNA) in bacterial and viral meningitis in children.
METHODS: The peripheral blood of five bacterial meningitis patients, five viral meningitis samples, and five healthy individuals were collected for RNA sequencing. Then, the differentially expressed lncRNA and mRNA were detected in bacterial meningitis vs. controls, viral meningitis vs. healthy samples, and bacterial vs. viral meningitis patients. Besides, co-expression and the competing endogenous RNA (ceRNA) networks were constructed. Receiver operating characteristic curve (ROC) analysis was performed.
RESULTS: Compared with the control group, 2 lncRNAs and 32 mRNAs were identified in bacterial meningitis patients, and 115 lncRNAs and 54 mRNAs were detected in viral meningitis. Compared with bacterial meningitis, 165 lncRNAs and 765 mRNAs were identified in viral meningitis. 2 lncRNAs and 31 mRNAs were specific to bacterial meningitis, and 115 lncRNAs and 53 mRNAs were specific to viral meningitis. The function enrichment results indicated that these mRNAs were involved in innate immune response, inflammatory response, and immune system process. A total of 8 and 1401 co-expression relationships were respectively found in bacterial and viral meningitis groups. The ceRNA networks contained 1 lncRNA-mRNA pair and 4 miRNA-mRNA pairs in viral meningitis group. GPR68 and KIF5C, identified in bacterial meningitis co-expression analysis, had an area under the curve (AUC) of 1.00, while the AUC of OR52K2 and CCR5 is 0.883 and 0.698, respectively.
CONCLUSIONS: Our research is the first to profile the lncRNAs in bacterial and viral meningitis in children and may provide new insight into understanding meningitis regulatory mechanisms.

Heparin-binding protein is a serine protease that is mobilized rapidly from emigrating polymorphonuclear leukocytes that acts as a chemoattractant activator of monocyte and macrophages. We investigated the potential role and efficacy of serum and cerebrospinal fluid heparin binding protein in differentiating bacterial meningitis from tuberculosis and viral meningitis. A case diagnosed with acute bacterial meningitis (n:37), viral meningitis (n:30) and tuberculous meningitis (n:30) was included in this study. The diagnosis was based on history, clinical criteria, cerebrospinal fluid examination, latex agglutination and culture, and response to therapy. Heparin-binding protein was measured using enzyme-linked immunosorbent technique in both cerebrospinal fluid and serum. Cerebrospinal fluid heparin-binding protein levels were 7.81 ± 0.23 ng/mL in bacterial meningitis, 6.11 ± 0.3 ng/mL in tuberculosis meningitis and 5.75 ± 0.1 ng/mL in viral meningitis. The mean serum level was 14.98 ± 1.1 ng/mL in bacterial meningitis, 6.89 ± 0.4 ng/mL in tuberculosis meningitis, and 6.02 ± 0.4 ng/mL in viral meningitis. Both heparin-binding protein levels were significantly higher in patients with bacterial meningitis. We found that serum and cerebrospinal fluid heparin binding protein is a useful marker for differentiating bacterial meningitis from non-bacterial meningitis.

Ramsay Hunt syndrome (RHS) is a manifestation of reactivated varicella-zoster virus (VZV) from the geniculate ganglion. Data on clinical features and outcomes of patients with RHS and concurrent VZV meningitis (henceforth RHS meningitis) are limited. Thus, we conducted a nationwide population-based cohort study of all adults hospitalized for RHS meningitis at the departments of infectious diseases in Denmark from 2015 to 2020. Patients with VZV meningitis without cranial nerve palsies were included for comparison. In total, 37 patients with RHS meningitis (mean annual incidence: 1.6/1 000 000 adults) and 162 with VZV meningitis without cranial nerve palsies were included. In RHS meningitis, the median age was 52 years (interquartile range: 35-64), and in addition to peripheral facial nerve palsy (100%), dizziness (46%), and hearing loss (35%) were common symptoms. The triad of headache, neck stiffness, and photophobia/hyperacusis was less common in RHS meningitis than in VZV meningitis without cranial nerve palsies (0/27 [0%] vs. 24/143 [17%]; p = 0.02). At 30 days after discharge, 18/36 (50%) patients with RHS meningitis had persistent peripheral facial nerve palsy, with no statistically significant difference between those treated with and without adjuvant glucocorticoids (6/16 [38%] vs. 12/20 [60%]; p = 0.18). Additional sequelae of RHS meningitis included dizziness (29%), neuralgia (14%), tinnitus/hyperacusis (11%), hearing loss (9%), headache (9%), fatigue (6%), and concentration difficulties (3%). In conclusion, clinical features and outcomes of RHS meningitis were primarily related to cranial neuropathies.