Strategies and new developments in the management of bacterial meningitis

C-REACTIVE PROTEIN (CRP) AS A SUPPORTING MARKER OF ANTIBIOTIC EFFECTIVENESS ON CENTRAL NERVOUS SYSTEM (CNS) INFECTIONS

Infection of the central nervous system in pediatric patients have a high mortality as well as acute and chronic neurological sequelae. Signs of the disease are unclear, so cerebrospinal fluid (CSF) test is used as a gold standard for diagnosis, but the investigation has faced many obtacles. Empiric antibiotic therapy is the key factor in reducing morbidity and mortality. Microbiological culture result is obtained within 5-7 days. The effectiveness of empirical antibiotic use is questionable. Therefore, other investigations are conducted to determine the effectiveness of antibiotics by using one marker, the CRP. This study was to analyze CRP level in supporting antibiotic therapy effectiveness in pediatric patients with central nervous system (CNS) infections. A prospective cohort study was conducted to determine the relationship of CRP with other parameters, including clinical, microbiological and laboratory, in pediatric patients with central nervous system infections. Patients meeting blood samples criteria were taken before (H0), the third day (H3) and the fifth day (H5) after antibiotics administration. This study involved 10 patients with central nervous system infections (meningoencephalitis, encephalitis and encephalitis with cerebral edema). Six patients were male, with ages less than a year. Antibiotic treatment effectiveness was associated with improved condition of the patients' CRP level. It was 3.558 ±3.196 before (H0), 3.878±2.813 on the third day (H3) and 3.891±2.204 on the fifth day (H5) after antibiotic administration. Leukocyte levels were 13.680±1.660 before (H0), 17.832±7.213 on the third day (H5), and 10.546±3.671 on the fifth day (H5) after antibiotic administration. Pearson's correlation test analysis performed on CRP and WBC parameters showed H0 p=0.981, CRP and WBC H3 p=0.621, while CRP and WBC H5 obtained significance p=0.644. There was no significant correlation observed between CRP and WBC parameters before and after antibiotic administration. In conclusion, there was no correlation of CRP levels with clinical, laboratory and micobiological parameters in patients with central nervous system infections.

Acute bacterial meningitis: current review and treatment update

Bacterial meningitis is an infection of the meninges that can be infected by bacteria, virus, or fungus. The classic triad of bacterial meningitis consists of fever, neck stiffness, and altered mental status; headache is also another common symptom. Interventions for bacterial meningitis include prompt diagnosis, and initiation of antimicrobial therapy to optimize bacterial kill and decrease inflammatory response in the subarachnoid space. Nursing management consists of effective delivery of antibiotic therapy, fluid management, and supportive care.

Advances in treatment of bacterial meningitis

Bacterial meningitis kills or maims about a fifth of people with the disease. Early antibiotic treatment improves outcomes, but the effectiveness of widely available antibiotics is threatened by global emergence of multidrug-resistant bacteria. New antibiotics, such as fluoroquinolones, could have a role in these circumstances, but clinical data to support this notion are scarce. Additionally, whether or not adjunctive anti-inflammatory therapies (eg, dexamethasone) improve outcomes in patients with bacterial meningitis remains controversial; in resource-poor regions, where the disease burden is highest, dexamethasone is ineffective. Other adjunctive therapeutic strategies, such as glycerol, paracetamol, and induction of hypothermia, are being tested further. Therefore, bacterial meningitis is a substantial and evolving therapeutic challenge. We review this challenge, with a focus on strategies to optimise antibiotic efficacy in view of increasingly drug-resistant bacteria, and discuss the role of current and future adjunctive therapies.

Treatment of Drug-resistant Pneumococcal Meningitis

The approach to therapy in patients with pneumococcal meningitis has changed considerably over the past 20 years. Given the emergence of pneumococcal strains that are intermediately susceptible or highly resistant to penicillin, penicillin is not recommended as empiric therapy for presumed pneumococcal meningitis; the combination of vancomycin and a third-generation cephalosporin (either cefotaxime or ceftriaxone) should be used, pending isolation of the organism and in vitro susceptibility testing. For patients with pneumococcal meningitis caused by highly penicillin- or cephalosporin-resistant strains, the addition of rifampin can be considered if the organism is susceptible in vitro, the expected clinical or bacteriologic response is delayed, or the pneumococcal isolate has a cefotaxime or ceftriaxone minimal inhibitory concentration greater than 4 μg/mL. Meropenem is not a good option for monotherapy of highly penicillin- or cephalosporin-resistant strains, but use of a fluoroquinolone with in vitro activity against Streptococcus pneumoniae (specifically moxifloxacin) is an option in patients failing standard therapy; if used, however, it should be combined with a third-generation cephalosporin or vancomycin. Newer glycopeptides, daptomycin, and linezolid require further study to determine their efficacy in patients with pneumococcal meningitis.

Treatment of meningitis caused by vancomycin-resistant Enterococcus faecium: high-dose and combination daptomycin therapy

OBJECTIVE

To report 3 successful treatments of vancomycin-resistant Enterococcus faecium meningitis in adults using daptomycin and either linezolid or gentamicin.

CASE SUMMARY

Three case reports involving males (aged 58-78 years) are presented; in each case (trigeminal nerve microvascular decompression and subdural hygroma; paraspinal abscess; and hydrocephalus with subsequent craniotomy and ventriculo-peritoneal shunt placement) CSF examination revealed vancomycin-resistant Enterococcus (VRE) susceptible to daptomycin, gentamicin, and/or linezolid. Threeto four-week treatment regimens with daptomycin 6-12 mg/kg and either gentamicin or linezolid led to clinical resolution and microbiological clearance of infection.

DISCUSSION

Daptomycin has previously been shown to be successful in treating methicillin-resistant Staphylococcus aureus-associated meningitis and other serious VRE and enterococcal infections. Higher than approved doses of daptomycin were used in 2 cases where in theory higher CSF concentrations would thus be obtained. Gentamicin and linezolid were added to daptomycin therapy based on in vitro data synergy results and because of documented successful treatment for VRE meningitis, respectively.

CONCLUSIONS

The difficulty in treating VRE CSF infections involves both drug kinetics and microbial resistance factors, as well as external factors such as foreign bodies like shunts. This report highlighted 3 cases where daptomycin use in concert with either gentamicin or linezolid was successful in treating this infection. Additional controlled trials will be helpful in identifying the best strategies when using daptomycin to treat CSF infections.