Bacterial purulent meningitis in children: is there a light at the end of the tunnel?

Bacterial purulent meningitis is a life-threatening disease characterized by high mortality and severe consequences in survivors. Despite the modern possibilities of medicine, the disease continues to be a heavy burden on health care, the economy and society everywhere.Aim. To draw the attention of doctors to the problems associated with modern features of epidemiology, the consequences and possibilities of preventing bacterial purulent meningitis, especially in children, who constitute the main risk group for the development of this pathology.Literature review of Russian and foreign publications on the problem under consideration presented.Vaccination is recognized as one of the main tools for reducing morbidity and mortality from meningitis. Prophylactic vaccinations against N. meningitidis, Str.pneumoniae, H. influenzae, along with strict adherence to anti-epidemic measures in hospitals providing care to newborns, can help reduce the incidence of purulent meningitis in children and improve outcomes if they develop.

Case Report: Diagnosis of Klebsiella pneumoniae Invasive Liver Abscess Syndrome With Purulent Meningitis in a Patient From Pathogen to Lesions

As a determinant human pathogen, Klebsiella pneumoniae is known to cause rare K. pneumoniae liver abscess syndrome (KLAS) which was more common in Asia in early-stage and reported increasingly outside Asia now. Patients with KLAS who have septic metastatic ocular or central nervous system (CNS) lesions are associated with high morbidity and mortality. Relatively infrequent adult community-acquired K. pneumoniae meningitis have been documented and most were with poor prognosis. In this paper, we reported a case of KLAS presenting purulent meningitis as disease onset. While negative results were obtained in the bacterial culture of CSF, blood, or liver pus, metagenomic next-generation sequencing (mNGS) of CSF, and blood samples which were synchronously performed demonstrated Klebsiella pneumoniae as the pathogenic microorganism (13,470 and 5,318 unique reads, respectively). The ultimately cured patient benefited from rapid pathogen diagnosis, early percutaneous drainage of the abscess, and prompt appropriate antibiotic administration. Our case highlights the importance of clinicians using mNGS for early pathogen diagnosis of this disease.

Preparation of Let-7b Nanocomposite and Its Effect on the Level of Inflammatory Factors in Cerebrospinal Fluid of Purulent Meningitis

This study was to explore the effect and mechanism of Let-7b nanocomposite on the expression of inflammatory factors in the cerebrospinal fluid (CSF) of purulent meningitis. 45 patients with purulent meningitis (PM) were selected as observation group (group A), and 38 patients with normal CSF without central nervous system diseases were selected as the control group (group B). The CSF of the two groups were collected to detect the inflammatory factors interleukin-8 (IL-8), macrophage inflammatory protein-1α (MIP-1α), matrix metalloproteinase 9 (MMP9), interleukin 1β (IL-1β), tumor necrosis factor-α (TNF-α), and Let-7b level with the double antibody sandwich enzyme-linked immunosorbent assay (ELISA). The Let-7b nanocomposite was prepared, and its morphology, particle size, and Zeta potential were analyzed. In addition, the degradation kinetics, cytotoxicity, and phagocytic efficiency (PE) of Let-7b nanocapsules were detected. 36 healthy adult New Zealand (NZL) rabbits were randomly grouped into a control group (group C) (0.9% normal saline (NS)), a model group (Escherichia coli (E. coli) modeling, group D), and a test group (E. coli modeling + Let-7b nanocapsules, group E), with 12 rabbits in each group. The changes of inflammatory factors in CSF of the three groups were detected and compared. It was found that the expression levels of IL-8 and IL-1 β in the group A were much higher than those in the group B (P < 0.01), and the MMP9 and TNF-α levels in the group B were much lower in contrast to the group A (P < 0.001). The expression of Let-7b in the group A was lower obviously in contrast to the group B (P < 0.001). Let-7b nanocapsules were irregularly spherical, with an average particle size (APS) of 23.1 nm, a polydispersity index (PDI) of 0.232, and the Zeta potential of around +15 mV. Let-7b nanocapsules showed obvious polymer shell absorption peaks at 1,015 cm-1, 1,228 cm-1, and 1,547 cm-1. The IL-8 and IL-1β levels of the group D were greatly different from those in the other two groups (P < 0.01). The levels of TNF-α and MMP9 in the group D were greatly different in contrast to the group C (P < 0.001) and the group E (P < 0.01). It indicated that Let-7b nanocomposite could lower the expression levels of IL-8, IL-1β, MMP9, and TNF-α in the CSF of patients with purulent meningitis dramatically, which provides a reliable basis for immunotherapy of purulent meningitis with Let-7b.

The pathology of natural and experimentally induced Campylobacter jejuni abortion in sheep

We describe here the gross and microscopic lesions in 18 experimentally induced and 120 natural Campylobacter abortions. In natural Campylobacter abortions, gross lesions were reported infrequently; placentitis was recorded in 6% and hepatic lesions in 4% of our field cases. Placentitis was the microscopic lesion identified most consistently in natural abortions (93%) and was often observed in association with abundant bacterial colonies in chorionic villi (54%) and less often with placental vasculitis (13%). In natural abortions, suppurative fetal pneumonia (48%), necrosuppurative hepatitis (16%), and purulent meningitis (7%) were also observed. The better-preserved specimens from experimentally induced abortions were utilized to define placental changes more precisely. Placentitis was identified in all 18 experimentally induced abortions and was observed most consistently in the chorionic villus stroma (100%), often accompanied by suppurative surface exudate (89%). An inflammatory infiltrate was less commonly identified in the cotyledonary hilus (39%) and intercotyledonary placenta (22%). Bacteria were visualized in H&E-stained sections in 89% of placentas from experimentally infected ewes, primarily as well-demarcated bacterial colonies within subtrophoblastic, sinusoidal capillaries (89%), in the cotyledonary villus stroma (89%), and within the cytoplasm of trophoblasts (22%). Transmission electron microscopy and immunohistochemistry confirmed that the vast majority of the well-demarcated bacterial colonies characteristic of Campylobacter abortion were within subtrophoblastic sinusoidal capillaries. The most characteristic microscopic lesions identified in cases of Campylobacter abortion in sheep were placentitis with placental bacterial colonies, placental vasculitis, and fetal pneumonia.

Impact of 13-valent pneumococcal conjugate vaccine on laboratory-confirmed pneumococcal meningitis and purulent meningitis among children ˂5 years in Cameroon, 2011–2018

Background The 13-valent pneumococcal conjugate vaccine (PCV13) entered Cameroon’s childhood national immunization programme (NIP) in July 2011 under a 3-dose schedule (6, 10, 14 weeks of age) without any catch-up. We described the impact of PCV13 onserotype distribution among pneumococcal meningitis cases over time. Methods We used laboratory-based sentinel surveillance data to identify meningitis cases among 2- to 59-month-old children with clinically-suspected bacterial meningitis (CSBM) admitted to hospitals in Yaoundé (August 2011-December 2018). Purulent meningitis cases had a cerebrospinal fluid (CSF) white blood cell (WBC) count ≥20 per mm3. Pneumococcal meningitis cases had S. pneumoniae identified from CSF, with serotyping by polymerase chain reaction. Years 2011-2014 were described as early PCV13 era (EPE) and years 2015-2018 as late PCV13 era (LPE) impact periods. Results Among children hospitalized with CSBM who had a lumbar puncture obtained, there was no significant change from the EPE versus the LPE in the percentage identified with purulent meningitis: 7.5% (112/1486) versus 9.4% (154/1645), p = 0.0846. The percentage of pneumococcal meningitis cases due to PCV13 vaccine-serotype (VST) decreased from 62.0% (31/50) during the EPE to 35.8% (19/53) in the LPE, p = 0.0081. The most frequent pneumococcal meningitis VSTs during the EPE were 6A/6B (30%) and 5 (6%), and during the LPE were 14 (13.2%), 3 (7.6%), 4 (5.6%) and 18C (5.6%). Conclusion Four to seven years after PCV13 introduction, the proportion of pneumococcal meningitis due to vaccine serotypes has declined, mainly due to reductions of serotypes 6A/6B, 1, 19A, and 23F; nevertheless, PCV13 VSTs remain common. Because the analyzed surveillance system was not consistent or population based, we could not estimate incidence or overall impact; this emphasizes the need for improved surveillance to document further the utility of PCV13 immunization in Cameroon.