Capnocytophaga species and preterm birth: case series and review of the literature

AbstractCapnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported

Neurogenic inflammation after traumatic brain injury and its potentiation of classical inflammation

Background: The neuroinflammatory response following traumatic brain injury (TBI) is known to be a key secondary injury factor that can drive ongoing neuronal injury. Despite this, treatments that have targeted aspects of the inflammatory pathway have not shown significant efficacy in clinical trials. Main body: We suggest that this may be because classical inflammation only represents part of the story, with activation of neurogenic inflammation potentially one of the key initiating inflammatory events following TBI. Indeed, evidence suggests that the transient receptor potential cation channels (TRP channels), TRPV1 and TRPA1, are polymodal receptors that are activated by a variety of stimuli associated with TBI, including mechanical shear stress, leading to the release of neuropeptides such as substance P (SP). SP augments many aspects of the classical inflammatory response via activation of microglia and astrocytes, degranulation of mast cells, and promoting leukocyte migration. Furthermore, SP may initiate the earliest changes seen in blood-brain barrier (BBB) permeability, namely the increased transcellular transport of plasma proteins via activation of caveolae. This is in line with reports that alterations in transcellular transport are seen first following TBI, prior to decreases in expression of tight-junction proteins such as claudin-5 and occludin. Indeed, the receptor for SP, the tachykinin NK1 receptor, is found in caveolae and its activation following TBI may allow influx of albumin and other plasma proteins which directly augment the inflammatory response by activating astrocytes and microglia. Conclusions: As such, the neurogenic inflammatory response can exacerbate classical inflammation via a positive feedback loop, with classical inflammatory mediators such as bradykinin and prostaglandins then further stimulating TRP receptors. Accordingly, complete inhibition of neuroinflammation following TBI may require the inhibition of both classical and neurogenic inflammatory pathways.Frances Corrigan, Kimberley A. Mander, Anna V. Leonard and Robert Vin

Proinflammatory cytokines and interleukin-9 exacerbate excitotoxic lesions of the newborn murine neopallium

Many prenatal and perinatal factors are hypothesized to play a role in the cause of cerebral palsy (CP). Epidemiological data implicate maternal-fetal infection and associated increase in circulating cytokines. Murine model data suggest that excitotoxic damage can produce pathological change in brain tissue consistent with lesions observed in CP. Specifically, on day 5 after birth, mouse pups injected with ibotenate, a glutamatergic analogue, develop transcortical necrosis and white matter cysts mimicking some human perinatal lesions associated with CP. The present study builds on this murine model to assess the modulating role of several cytokines on the development of excitotoxic lesions. Pups pretreated with interleukin (IL)-1beta, IL-6, IL-9, or tumor necrosis factor-alpha developed significantly larger ibotenate-induced cortical and white matter damage than controls; IL-4 did not produce such an effect. In a similar manner, IL-9-overexpressing transgenic pups developed ibotenate-induced brain lesions, which were significantly larger than those induced in nontransgenic control pups. Pretreatment with proinflammatory cytokines significantly increased neopallial microglial density without affecting astrocytic density; IL-9 or IL-4 did not produce a similar effect. To our knowledge, this is the first in vivo study to demonstrate that systemically administered proinflammatory cytokines and IL-9 exacerbate brain lesions that are similar to those found in human infants with CP

Prise en charge de la prématurité extrême. Réflexions du département hospitalo-universitaire (DHU) « risques et grossesse » [Perinatal care for extremely preterm infants. Considerations of the "risks in pregnancy" department]

Decisions regarding whether to initiate or forgo intensive care for extremely premature infants are often based on gestational age alone. However, other factors also affect the prognosis for these patients and must be taken into account. After a short review of these factors, we present the thoughts and proposals of the Risks and Pregnancy department. The proposals are to limit emergency decisions, to better take into account other factors than gestational age and prenatal predicted fetal weight in assessing the prognosis, to introduce multidisciplinary consultation in the evaluation and proposals that will be discussed with the parents, and to separate prenatal steroid therapy from decision-making regarding whether or not to administer intensive care