Community-acquired bacterial meningitis

Pneumolysin promotes host cell necroptosis and bacterial competence during pneumococcal meningitis as shown by whole animal dual RNA-seq

“…Activation of the immune system in the cerebrospinal fluid is dependent on PRRs (van de Beek et al, 2016; Mook-Kanamori et al, 2011). In our study, we found that the TLR signaling pathway, RIG-I-like receptor pathway, and NOD-like receptor signaling pathway were enriched in zebrafish larvae infected with pneumococci that produce pneumolysin (Figure 2D, Table S2).…”

“…Upon invasion, the pathogen will be detected by pattern recognition receptors (PRRs), leading to the activation of the innate immune response that will try to eliminate the pneumococci. In turn, pneumococci will counteract by employing a variety of strategies to escape from eradication by the host’s immune response (van de Beek et al, 2021; Henriques-Normark and Tuomanen, 2013; Kadioglu et al, 2008; Weiser et al, 2018). Insight into these complex host-pneumococcus interaction dynamics may lead to better understanding in the factors leading to poor disease outcome and to develop new intervention strategies (van de Beek, 2012).…”

The gut–meningeal immune axis: Priming brain defense against the most likely invaders

“…In addition to defending against local invaders, the meninges must also protect the CNS from infectious challenges that metastasize via the hematogenous route. Such hematogenous spread is thought to account for the majority of community-acquired bacterial meningitis ( van de Beek et al, 2021 ), and given that dural vascular endothelium is fenestrated, it is an area of vulnerability for the CNS, as discussed previously. The underlying microbial causes of meningitis vary with patient demographics, clinical context, and environmental exposure.…”

“…The underlying microbial causes of meningitis vary with patient demographics, clinical context, and environmental exposure. However, it is notable that the majority of these blood-borne infections are thought to derive from the respiratory tract ( van de Beek et al, 2021 ). Hence, Pneumococcus, Meningococcus, and Haemophilus influenzae B are globally the most common causes of bacterial community-acquired meningitis, and enter the host bloodstream via the respiratory tract mucosa ( van de Beek et al, 2021 ).…”

Bacterial meningitis presenting with a normal cerebrospinal fluid leukocyte count

“…Community-acquired bacterial meningitis is associated with high mortality and morbidity rates despite effective vaccination strategies. (1)(2)(3) Early diagnosis and initiation of treatment with antibiotics and dexamethasone is crucial and European guidelines recommend initiation of treatment within one hour after arrival in the hospital. ( 4 , 5 ) Cerebrospinal fluid (CSF) findings play an important role in the diagnosis of bacterial meningitis.…”