Central nervous system bacterial infections

Gastroenteritis infection with non-typhoidal salmonella often results in gastroenteritis indistinguishable from that caused by other bacterial or viral pathogens. It is usually self-limited, and fever and diarrhoea resolve within 3 and 7 days, respectively. In a minority of patients (<5%), particularly neonates, infants, elderly and immunocompromised patients, carriage of the pathogen and/or a bacteraemia is prolonged with endovascular or localised (intraabdominal, central nervous system, pulmonary) infections. 

The treatment of bacterial infections of the central nervous system highlights a number of important therapeutic considerations. Bacterial meningitis is caused by a variety of bacteria although their incidence varies with age. In the neonate, E. coli and group B streptococci account for the majority of infections, while in the preschool child H. influenzae is the commonest pathogen. Neisseria meningitidis has a... 

Blood-brain barrier Treatment of central nervous system infections, such as meningitis, depends on the ability of a drug to penetrate into the cerebrospinal fluid (CSF). The blood-brain barrier (see p. 8) ordinarily excludes many antibiotics. However, inflammation facilitates penetration and allows sufficient levels of many (but not all) antibiotics to enter the CSF. [Note For cure of meningitis, it is important that a bactericidal rather than a bacteriostatic effect is achieved in the CSF. Yet, this is not without its problems, since rapid bacteriolysis in the infected CSF will liberate high concentrations of bacterial cell walls and lipopolysaccharide that can exacerbate the inflammation. This has led to the use of adjunctive (simultaneous administration of) corticosteroids, which diminish the inflammatory process and neurologic sequelae.]... 

Bacterial infections elicit a series of acute-phase responses which include central nervous system effects such as changes in body temperature and increased slow-wave sleep. Dead bacteria [54] and murein preparations [55] as well as other bacterial cell-wall products induce similar responses. Intravenous injections of rabbits with suspensions of pseudomurein from Methanobacterium thermoautotrophicum also alter sleep and brain temperature. The mechanisms responsible for these somnogenic and pyrogenic effects are unknown [56]. It has been demonstrated that in a rat arthritis model, intra-articular injection of high doses of pseudomurein-polysaccharide fragments from Methanobacterium formicicum caused an acute inflammation [57]. 

There is a blood-brain barrier that protects the central nervous system (CNS) by excluding large molecules from contacting CNS neurons. It has been reported (Brodie, 2006) that infection or stress can allow certain large molecules access to specific parts of the brain. Bacterial endotoxin or adrenaline have both been shown to breach the blood-brain barrier and permit access to brain nerve cells by autoimmune antibodies. These antibodies normally cause such autoimmune diseases such as lupus, rheumatoid arthritis, or multiple sclerosis (a disease of the peripheral nervous system), but have no effect on brain function. Infections or stress can change that and result in alterations to memory or emotions. This underscores the connections between the body and the brain. 

The influence of natural products in the discovery of new marketed therapeutics continues to be significant in various therapeutic areas. Burger s Medicinal Chemistry and Drug Discovery reviews natural products as leads for new pharmaceutical products for the central nervous system, neuromuscular disease, cancer, bacterial infections, cardiovascular disease, asthma, and parasites. Dmgs such as morphine, penicillin, cyclosporine A, lovastatin, acarbose, FK506 (tacrolimus), and pachtaxel (Taxol )... 

The benefits and harms associated with the use of intrathecal narcotic infusion pumps for intractable pain of chronic pancreatitis have been studied in 13 patients, of whom three developed major complications—a central nervous system infection requiring pump removal, cerebrospinal fiuid leakage requiring laminectomy, and a perispinal abscess with bacterial meningitis requiring pump removal [57 ]. 

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