Clinical presentations, diagnosis, and prognostic factors of bacterial meningitis

Diagnosis of Enterococcus faecalis meningitis associated with long-term cerebrospinal fluid rhinorrhoea using metagenomics next-generation sequencing: a case report

Background

Enterococcus faecalis (E. faecalis) meningitis is a rare disease, and most of its occurrences are of post-operative origin. Its rapid diagnosis is critical for effective clinical management. Currently, the diagnosis is focused on cerebrospinal fluid (CSF) culture, but this is quite limited. By comparison, metagenomic next-generation sequencing (mNGS) can overcome the deficiencies of conventional diagnostic approaches. To our knowledge, mNGS analysis of the CSF in the diagnosis of E. faecalis meningitis has been not reported.

Case presentation

We report the case of E. faecalis meningitis in a 70-year-old female patient without a preceding history of head injury or surgery, but with an occult sphenoid sinus bone defect. Enterococcus faecalis meningitis was diagnosed using mNGS of CSF, and she recovered satisfactorily following treatment with appropriate antibiotics and surgical repair of the skull bone defect.

Conclusions

Non-post-traumatic or post-surgical E. faecalis meningitis can occur in the presence of occult defects in the cranium, and mNGS technology could be helpful in diagnosis in the absence of a positive CSF culture.

Rapid pathogen identification using a novel microarray-based assay with purulent meningitis in cerebrospinal fluid

In order to improve the diagnosis of pathogenic bacteria in cerebrospinal fluid (CSF) with purulent meningitis, we developed a DNA microarray technique for simultaneous detection and identification of seven target bacterium. DNA were extracted from 24 CSF samples with purulent meningitis (or suspected purulent meningitis). The specific genes of each pathogen were chosen as the amplification target, performed the polymerase chain reaction (PCR), labeled with a fluorescence dye, and hybridized to the oligonucleotide probes on the microarray. There is no significant cross-hybridization fluorescent signal occurred in untargeted bacteria. There were 87.5% (21/24) positive results in DNA microarray compared with the 58.3% (14/24) of the CSF culture test. Of which 58.3% (14/24) of the patients with culture-confirmed purulent meningitis, 37.5% (9/24) patients who were not confirmed by culture test but were demonstrated by the clinical diagnosis and DNA microarray. Multiple bacterial infections were detected in 5 cases by the microarray. In addition, the number of gene copies was carried out to determine the sensitivity of this technique, which was shown to be 3.5 × 10¹ copies/μL. The results revealed that the microarray technique which target pathogens of the CSF specimen is better specificity, accuracy, and sensitivity than traditional culture method. The microarray method is an effective tool for rapidly detecting more target pathogens and identifying the subtypes of strains which can eliminate the impact of the different individuals with purulent meningitis for prompt diagnosis and treatment.

Antimicrobial sensitivity patterns of cerebrospinal fluid (CSF) isolates in Namibia: implications for empirical antibiotic treatment of meningitis

OBJECTIVE

Bacterial meningitis is a medical emergency associated with high mortality rates. Cerebrospinal fluid (CSF) culture is the "gold standard" for diagnosis of meningitis and it is important to establish the susceptibility of the causative microorganism to rationalize treatment. The Namibia Standard Treatment Guidelines (STGs) recommends initiation of empirical antibiotic treatment in patients with signs and symptoms of meningitis after taking a CSF sample for culture and sensitivity. The objective of this study was to assess the antimicrobial sensitivity patterns of microorganisms isolated from CSF to antibiotics commonly used in the empirical treatment of suspected bacterial meningitis in Namibia.

METHODS

This was a cross-sectional descriptive study of routinely collected antibiotic susceptibility data from the Namibia Institute of Pathology (NIP) database. Results of CSF culture and sensitivity from January 1, 2009 to May 31, 2012, from 33 state hospitals throughout Namibia were analysed.

RESULTS

The most common pathogens isolated were Streptococcus species, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and Escherichia coli. The common isolates from CSF showed high resistance (34.3% -73.5%) to penicillin. Over one third (34.3%) of Streptococcus were resistance to penicillin which was higher than 24.8% resistance in the United States. Meningococci were susceptible to several antimicrobial agents including penicillin. The sensitivity to cephalosporins remained high for Streptococcus, Neisseria, E. coli and Haemophilus. The highest percentage of resistance to cephalosporins was seen among ESBL K. pneumoniae (n = 7, 71%-100%), other Klebsiella species (n = 7, 28%-80%), and Staphylococcus (n = 36, 25%-40%).

CONCLUSIONS

The common organisms isolated from CSF were Streptococcus Pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and E. coli. All common organisms isolated from CSF showed high sensitivity to cephalosporins used in the empirical treatment of meningitis. The resistance of the common isolates to penicillin is high. Most ESBL K. pneumoniae were isolated from CSF samples drawn from neonates and were found to be resistant to the antibiotics recommended in the Namibia STGs. Based on the above findings, it is recommended to use a combination of aminoglycoside and third-generation cephalosporin to treat non-ESBL Klebsiella isolates. Carbapenems (e.g., meropenem) and piperacillin/tazobactam should be considered for treating severely ill patients with suspected ESBL Klebsiella infection. Namibia should have a national antimicrobial resistance surveillance system for early detection of antibiotics that may no longer be effective in treating meningitis and other life-threatening infections due to resistance.

Bacterial meningitis post-PCV7: declining incidence and treatment

The epidemiology of bacterial meningitis in the United States has changed tremendously in the past 20 years. Since the introduction of the Haemophilus influenzae type b vaccine in 1988, the incidence of H. influenzae type b meningitis has declined by at least 97%, and Streptococcus pneumoniae has emerged as the most common etiologic agent. The PCV7 (7-valent pneumococcal conjugate vaccine [Prevnar]; Wyeth Pharmaceuticals) vaccine, which targets 7 pneumococcal serotypes, was introduced in 2000 and has had an enormous impact on both the incidence and epidemiology of bacterial meningitis. This article reviews the impact of the PCV7 vaccine and the most up-to-date evidence on diagnosis and empiric therapy of suspected bacterial meningitis in the current day.

Association of treatment for bacterial meningitis with the development of sequelae

BACKGROUND

Bacterial meningitis continues to be a serious, often disabling infectious disease. The aim of this study was to assess the possibility that treatment influences the development of sequelae in childhood bacterial meningitis.

METHODS

Two thousand four hundred and seventy-seven patients aged 1 month to 14 years with acute bacterial meningitis over a 32-year period were enrolled in the study. Data were collected prospectively from the Meningitis Registry of a tertiary university teaching hospital in Athens, Greece. Treatment was evaluated through univariate and multivariate analysis with regard to sequelae: seizure disorder, severe hearing loss, ventriculitis, and hydrocephalus.

RESULTS

According to the multinomial logistic regression analysis, there was evidence that penicillin, an all-time classic antibiotic, had a protective effect on the occurrence of ventriculitis (odds ratio (OR) 0.17, 95% confidence interval (CI) 0.05-0.60), while patients treated with chloramphenicol had an elevated risk of ventriculitis (OR 17.77 95% CI 4.36-72.41) and seizure disorder (OR 4.72, 95% CI 1.12-19.96). Cephalosporins were related to an increased risk of hydrocephalus (OR 5.24, 95% CI 1.05-26.29) and ventriculitis (OR 5.72, 95% CI 1.27-25.76). The use of trimethoprim/sulfamethoxazole increased the probability of seizure disorder (OR 3.26, 95% CI 1.08-9.84) and ventriculitis (OR 8.60, 95% CI 2.97-24.91). Hydrocortisone was associated with a rise in hydrocephalus (OR 5.44, 95% CI 1.23-23.45), while a protective effect of dexamethasone (OR 0.82, 95% CI 0.18-3.79) was not statistically significant.

CONCLUSIONS

Current study findings suggest that the type of antimicrobial treatment for childhood bacterial meningitis may influence in either a positive or a negative way the development of neurological sequelae.

Clinical characteristics and prognostic factors in childhood bacterial meningitis: a multicenter study

OBJECTIVE

To evaluate clinical features and sequela in children with acute bacterial meningitis (ABM).

STUDY DESIGN

Multicenter retrospective study.

MATERIAL AND METHODS

Study includes retrospective chart review of children hospitalised with ABM at 11 hospitals in İstanbul during 2005. Follow up visits were conducted for neurologic examination, hearing evaluation and neurodevelopmental tests.

RESULTS

Two hundred and eighty three children were included in the study. Median age was 12 months and 68.6% of patients were male. Almost all patients had fever at presentation (97%). Patients younger than 6 months tended to present with feeding difficulties (84%), while patients older than 24 months were more likely to present with vomitting (93%) and meningeal signs (84%). Seizures were present in 65 (23%) patients. 26% of patients were determined to have at least one major sequela. The most common sequelae were speech or language problems (14.5%). 6 patients were severely disabled because of meningitis. Presence of focal neurologic signs at presentation and turbid cerebrospinal fluid appearance increased sequelae significantly. Childen under 24 months of age developed neurologic sequelae more commonly than older children.

CONCLUSION

Symptoms and signs were largely depending on the age of the patient. Speech or language problems were the most common sequelae following meningitis.

Neuro-intensive care of patients with acute CNS infections

Infections in the central nervous system (CNS) are caused by a wide range of microorganisms resulting in distinct clinical syndromes including meningitis, encephalitis, and pyogenic infections, such as empyema and brain abscess. Bacterial and viral infections in the CNS can be rapidly fatal and can result in severe disability in survivors. Appropriate identification and acute management of these infections often occurs in a critical care setting and is vital to improving outcomes in this group of patients. This review of diagnosis and management of acute bacterial and viral infections in the CNS provides a general approach to patients with a suspected CNS infection and also provides a more detailed review of the diagnosis and management of patients with suspected bacterial meningitis, viral encephalitis, brain abscess, and subdural empyema.

The use of dexamethasone in bacterial meningitis in children and adults: a retrospective analysis

Bacterial meningitis is a life-threatening illness that results from bacterial infection of the meninges and is associated with high mortality and morbidity rate, especially when the Streptococcus pneumoniae is the causative agent. Dexamethasone as adjunctive therapy to antibiotics does not influence the outcome or the complications in children as well as in adults suffering bacterial meningitis. However, we identified some prognostic parameters in the outcome of bacterial meningitis, and when dexamethasone was given in presence of at least one of 3 poor prognostic CSF parameters (WBC < 1000/mm³, glucose < 20 mg/dl, lactate > 10 mg/dl) it substantially improved the outcome.

Cerebrospinal fluid characteristics of infants who present to the emergency department with fever: establishing normal values by week of age

BACKGROUND This study describes differences in the values of cerebrospinal fluid (CSF) white blood cell (WBC), glucose, and protein counts in infants less than 60 days of age with fever who were not proven to have viral or bacterial meningitis.

METHODS

Three independent retrospective medical record reviews were conducted using a population of infants less than 60 days of age who presented to the Emergency Department with fever. Full-term infants were included if a lumbar puncture was performed within 24 hours of admittance and bacterial or viral meningitis was not identified as the cause of fever.

RESULTS

A total of 1091 infants were included and grouped by week of age. Significant trends were found for CSF WBC and CSF protein with the highest values observed during the first week of life. Mean for CSF WBC was 8.63 cells/mm for infants aged 0 to 1 week and decreased for each age group ending with infants 8 weeks of age having a mean of 2.22 cell/mm. For CSF protein, a similar trend was observed. No significant differences were found for CSF glucose.

CONCLUSIONS

Significant differences exist for infants by week of age for CSF WBC and CSF protein. These values can be used to assist in interpreting laboratory findings and making management decisions for infants less than 60 days of age.

An unusual case of meningococcal meningitis complicated with subdural empyema in a 3 month old infant: a case report

Subdural empyema is an unusual complication of meningococcal meningitis, and in acute cases can be rapidly fatal. We present a case of an 8 week old infant who presented with atypical Neisseria meningitis with bifrontal subdural empyema formation. Through the utilisation of modern polymerise chain reaction tests on cerebrospinal fluid samples, we were able to confirm the diagnosis and institute appropriate treatment. Early surgical intervention and appropriate intravenous antibiotics meant that the patient fully recovered. In summary, early treatment of meningitis without adequate microbiological investigations can complicate later diagnosis of subdural empyema. Early suspicion of empyema should be considered when patient fails to improve after 48 hrs, seizures are a late sign and gives a poorer prognosis. Computed tomography scanning is still the modality of choice although in this case, magnetic resonance imaging had its benefits. Polymerase chain reaction of cerebrospinal fluid testing may also provide an important confirmatory test in future.

An unusual case of meningococcal meningitis complicated with subdural empyema in a 3 month old infant: a case report

Subdural empyema is an unusual complication of meningococcal meningitis, and in acute cases can be rapidly fatal. We present a case of an 8 week old infant who presented with atypical Neisseria meningitis with bifrontal subdural empyema formation. Through the utilisation of modern polymerise chain reaction tests on cerebrospinal fluid samples, we were able to confirm the diagnosis and institute appropriate treatment. Early surgical intervention and appropriate intravenous antibiotics meant that the patient fully recovered. In summary, early treatment of meningitis without adequate microbiological investigations can complicate later diagnosis of subdural empyema. Early suspicion of empyema should be considered when patient fails to improve after 48 hrs, seizures are a late sign and gives a poorer prognosis. Computed tomography scanning is still the modality of choice although in this case, magnetic resonance imaging had its benefits. Polymerase chain reaction of cerebrospinal fluid testing may also provide an important confirmatory test in future.

Acute bacterial meningitis

Despite advances in medical care including antibiotics and vaccines, meningitis still has a high morbidity and mortality rate, especially in certain high-risk patients. Early diagnosis with the administration of appropriate antibiotics remains the key element of management. This article highlights methods of diagnosis, differential diagnoses, treatment options, and complications of treating bacterial meningitis.

Cerebrospinal creatinine kinase level in children with meningitis

BACKGROUND

The aim of this study is to evaluate the diagnostic value of the enzyme creatine kinase (CK) in the cerebrospinal fluid (CSF) of children with meningitis.

METHOD

CSF samples were collected from seventy one children suspected of having meningitis. The levels of total CK, CK-BB, Glucose, total protein, WBC counts, and culture were determined in the CSF. The cutoff value for total CK in the CSF was defined as 18 U/L.

RESULTS

Three cases (4%) of bacterial meningitis and 11 cases (15%) of aseptic meningitis were confirmed by culture. The sensitivity and specificity of total CK CSF level alone to diagnose bacterial meningitis were found to be 33% and 91% respectively. The positive and negative predictive values were found to be 14% and 98% respectively. On the other hand, the sensitivity and specificity of total CK level in aseptic meningitis were found to be 40% and 98% respectively and the positive and negative predictive values were 86% and 94% respectively. The sensitivity and specificity of total protein and glucose in CSF were also calculated. Streptococcus pneumonia and homophiles influenza were the main types identified in our cases.

DISCUSSION AND CONCLUSION

Measuring the total CK level in the CSF may be very useful in diagnosis of meningitis if only combined with other CSF markers. It is not of any much benefit if it is used solely.

Pooled analysis of 2,408 cases of acute adult purulent meningitis from Turkey

OBJECTIVES

The aim of this study was to systematically review the Turkish literature of acute adult purulent meningitis.

MATERIALS AND METHODS

The published series of three national databases and two international databases were searched to perform the review. In addition to the databases, abstracts of congresses held between 1994 and 2003 by the Turkish Clinical Microbiology and Infectious Diseases Association, Turkish Microbiology Association, and the Antibiotic and Chemotherapy Association were searched for reports about acute purulent meningitis.

RESULTS

Data for 2,408 patients with a diagnosis of acute purulent meningitis were obtained from 30 reports. In terms of clinical findings, 1,254 of 1,570 (79.8%) had fever (>38 degrees C), 1,408 of 1,595 (88.2%) headache, 1,403 of 1,562 (89.8%) stiffness of the neck, and 649 of 784 (82.7%) leukocytosis (>10,000/mm(3)). Cerebrospinal fluid culture yielded a pathogen in 873 of 2,260 (38.6%) patients. The most common pathogen was Streptococcus pneumoniae, followed by Neisseria meningitidis and Staphylococcus aureus. Overall mortality was 425 of 2,408 (17.6%). Pathogen-specific mortality was 60 of 202 (29.7%) for S. pneumoniae and 6 of 100 (6%) for N. meningitidis.

CONCLUSION

Meningitis is a serious, life-threatening disease. More preventive measures should be sought to further decrease the mortality and morbidity related to acute purulent meningitis.

Oxidant and antioxidant parameters in the treatment of meningitis

The aim of this study was to assess the effects of meningitis treatment on the serum and cerebrospinal-fluid oxidant and antioxidant status in children with bacterial meningitis. Forty children with bacterial meningitis, at ages ranging from 4 months to 12 years (mean age, 4 years), were enrolled in the study. Within 8 hours after admission (before treatment) and 10 days after clinical and laboratory indications of recovery (after treatment), cerebrospinal fluid and venous blood were collected. Thirty-seven healthy children (mean age, 4 years) were enrolled as control subjects, and only venous blood was collected. Serum total oxidant status, lipid hydroperoxide, oxidative stress index, uric acid, albumin, and ceruloplasmin levels were lower in the patient group after treatment (P<0.05). Serum total antioxidant capacity levels, vitamin C, total bilirubin, and catalase concentrations were not significantly altered by treatment (P>0.05). However, cerebrospinal fluid total oxidant status, lipid hydroperoxide, and oxidative stress index levels were higher, and cerebrospinal fluid total antioxidant capacity levels were lower after treatment than before treatment (P<0.05). In conclusion, we demonstrated that serum oxidative stress was lower, and cerebrospinal fluid oxidative stress was higher, after rather than before treatment in children with bacterial meningitis.

Total antioxidant/oxidant status in meningism and meningitis

The objective of this study was to investigate the antioxidant/oxidant status of serum and cerebrospinal fluid in children with meningismus and acute bacterial meningitis. Twenty-three children (age range, 0.75 to 9 years) with fever and meningeal signs that required analysis of the cerebrospinal fluid, but no cytologic or biochemical evidence of meningitis in their serum and cerebrospinal fluid, constituted the meningismus group. Thirty-one children (age range, 0.5 to 10 years) with acute bacterial meningitis constituted the meningitis group. Twenty-nine healthy children (age range, 0.5 to 11 years) were recruited as control subjects. Antioxidant status (ascorbic acid, albumin, thiol, uric acid, total bilirubin, total antioxidant capacity, catalase and ceruloplasmin concentrations) and oxidant status (lipid hydroperoxide and total oxidant status) were measured. The serum antioxidant status was lower, and oxidant status levels higher in both meningitis and meningismus subjects than in the control children (P < 0.001). Cerebrospinal fluid oxidant status was lower in the meningitis group than in the meningismus group (P < 0.05). These results indicate that serum antioxidant status was lower, and serum oxidant status was higher in children in the meningismus and meningitis groups, whereas cerebrospinal fluid oxidant status was higher in the meningismus group than in the meningitis group.

Long-term beneficial effects of dexamethasone on intellectual and neuropsychological outcome of children with pneumococcal meningitis

A Substantial ratio of bacterial meningitis survivors suffers mild or serious intellectual and neuropsychological handicaps. We organized eighty subjects into three groups: 1) Pneumococcal meningitis (PM) who did not receive dexamethasone, 2) PM who received dexamethasone, 3) Other bacterial meningitis with different etiology. All subjects underwent Bender Visual Motor Gestalt test and age-appropriate Intelligence quotient (IQ) tests. The mean full-scale IQ scoring fell within normal range (90+/-17) in the post-meningitic cohort. There was no statistical difference between two pneumococcal groups regarding full scale IQ testing (88+/-16 and 91+/-18) and Bender-Gestalt scoring (4.0+/-3.3 and 3.8+/-2.6), respectively. However, the subjects with full scale IQ score <85 (below the average) were statistically less in the group with steroid therapy. PM patients who received dexamethasone therapy had statistically better academic performance. As a result, adjuvant steroid therapy has no significant impact on overall intellectual tests in PM subjects. However, dexamethasone seems to diminish development of below the average IQ scoring in PM cases. In addition, PM subjects who received steroids showed better academic achievement. These findings may support the idea of dexamethasone administration prior to first antibiotic dose in PM subjects.

Streptococcus pneumoniae: description of the pathogen, disease epidemiology, treatment, and prevention

Streptococcus pneumoniae causes significant morbidity and mortality. Children younger than 2 years and individuals older than 65 years experience the highest rates of pneumococcal disease. Efforts to treat pneumococcal disease have been complicated by increasing resistance to antimicrobials. Prevention efforts have included the pneumococcal polysaccharide vaccines and the pneumococcal conjugate vaccines, with use of these vaccines targeted to those at highest risk for disease. Information and background on S. pneumoniae and pneumococcal disease are provided. Vaccines targeted at this pathogen are reviewed, and the clinical trials that evaluated their safety, efficacy, and effectiveness are summarized. Also provided are recommendations for use of these vaccines.

[The use of magnetic resonance and MR angiography in the detection of cerebral infarction--a complication of pediatric bacterial meningitis]

BACKGROUND

Association of both cerebral infarction and acute bacterial meningitis is more common in younger patients than in the elderly. The rate of mortality and the frequency of sequela are very high inspite of the use of modern antibiotic therapy. In more than 30% of the cases of childhood bacterial meningitis, both arterial and venous infarctions can occur. The aim of this study was to present the role of the use of magnetic resonance (MRI), and MR angiography (MRA) in the detection of bacterial meningitis in children complicated with cerebral infarctions.

METHOD

In the Centre for MR, the Clinical Centre of Serbia, 25 patients with the diagnosis of bacterial meningitis, of which 9 children with cerebral infarction whose clinical condition deteriorated acutely, despite the antibiotic therapy, underwent MRI and MR angiography examination on a 1T scanner. Examination included the conventional spin-echo techniques with T1-weighted saggital and coronal, and T2- weighted axial and coronal images. Coronal fluid attenuated inversion recovery (FLAIR) and the postcontrast T1-weighted images in three orthogonal planes were also used. The use MR angiography was accomplished by the three-dimensional time-of-flight (3D TOF) technique.

RESULTS

The findings included: multiple hemorrhagic infarction in 4 patients, multiple infarctions in 3 patients, focal infarction in 1 patient and diffuse infarction (1 patient). Common sites of involvement were: the frontal lobes, temporal lobes and basal ganglia. The majority of infarctions were bilateral. In 3 of the patients empyema was found, and in 1 patient bitemporal abscess was detected. In 8 of the patients MR angiography confirmed inflammatory vasculitis.

CONCLUSION

Infarction is the most common sequela of severe meningitis in children. Since the complication of cerebral infarction influences the prognosis of meningitis, repetitive MRI examinations are very significant for the evaluation of the time course of vascular involvement. The use of MRI, especially FLAIR imaging, confirmed its value in the detection and determination of the site and the extent of cerebral infarction. Non-invasive technique of examination, 3D TOF MR angiography clearly shoud show the presence of inflammatory vasculitis.

Bacterial meningitis in children

Microbiologic causes of meningitis include bacteria, viruses, fungi, and parasites. Before routine use of pneumococcal conjugate vaccine, bacterial meningitis affected almost 6000 people every year in the United States, and about half of all cases occurred in children 18 years old or younger. Prompt and accurate diagnosis and adequate treatment of bacterial meningitis in children remains a major challenge, as reflected by the continued high morbidity and case-fatality rates of the disease worldwide. Appropriate use of antibiotics, along with adjunctive therapies, such dexamethasone, has proved helpful in the prevention of neurologic sequelae in children with bacterial meningitis. Better understanding of pathophysiologic mechanisms likely would result in more effective therapies in the future.

Enterococcal meningitis: a clinical study of 39 cases and review of the literature

To describe the clinical features and outcome of enterococcal meningitis, we retrospectively reviewed the charts of 39 cases seen at 2 tertiary hospitals during a 25 years and collected 101 additional, previously reported cases for review. Among these 140 cases, there were 82 cases (59%) of postoperative meningitis and 58 cases (41%) of spontaneous meningitis. Eighty-six patients (61%) were adults and 54 (39%) were children. Patients with spontaneous meningitis had a higher frequency of community-acquired infection (50% versus 18%; p < 0.01), severe underlying diseases (67% versus 22%; p < 0.01), and associated enterococcal infection (29% versus 8%; p < 0.01) than patients with postoperative meningitis. The clinical presentation was similar in both groups, but patients with spontaneous infection had a higher frequency of bacteremia (58% versus 12%; p < 0.01), and a lower frequency of mixed infection (9% versus 29%; p < 0.01). Spontaneous meningitis in children was associated with a significantly lower frequency of fever, altered mental status, headache, and meningeal signs (p < 0.01), probably explained by the high proportion of neonates in this age-group. Most infections were caused by Enterococcus faecalis, which accounted for 76% of the isolates identified at the species level. Fifteen of the 25 cases due to Enterococcus faecium were produced by vancomycin-resistant strains. Most patients were treated with ampicillin, penicillin, or vancomycin, with or without aminoglycosides, for a median period of 18 days (range, 1-85 d). Overall mortality was 21%. The mortality rate was higher in spontaneous than in postoperative meningitis (33% versus 12%; p < 0.01), but was similar in patients treated with beta-lactams (18%), glycopeptides (14%), or other antibiotics (25%), as well as in patients treated with monotherapy (16%) or combination therapy (22%). An adverse outcome correlated significantly with advanced age, the presence of severe underlying diseases, associated enterococcal infection, bacteremia, septic shock, and the absence of fever at presentation. Shunt removal was associated with a lower mortality. Multivariate analysis showed that the presence of severe underlying diseases was the only prognostic factor associated with mortality (odds ratio = 6.8, 95% confidence intervals = 2.7-17.5, p < 0.01).

Bacterial meningitis in children

This review comprises aspects of the epidemiology, microbiology, pathophysiology, clinical manifestations, diagnosis, management, prognosis, and prevention of bacterial meningitis, with emphasis on the paediatric population. The beginning of this millennium has witnessed the virtual disappearance of Haemophilus invasive disease in some countries, emergence of pneumococcal strains that are resistant to multiple antibiotics, isolation of pneumococci with tolerance to vancomycin, outbreaks and clusters of meningococcal meningitis in several geographical areas, and intense research in development of effective conjugate pneumococcal and meningococcal vaccines. Bacterial meningitis has become an uncommon disease in the developed world. Unfortunately, because of limited economic resources and poor living conditions, many developing countries are still affected by the devastating consequences of this life-threatening systemic infection. Basic and clinical research is needed to discover new antimicrobial and anti-inflammatory agents to improve outcome from disease. Novel strategies are needed to distribute and implement effective vaccines worldwide to prevent bacterial meningitis.

Sequelae after bacterial meningitis in childhood

The neurological outcome of bacterial meningitis in children was evaluated retrospectively. Data were obtained from a large study on children aged between 1 month and 15 y who initially visited the emergency department of Sophia Children's Hospital, Rotterdam, The Netherlands with meningeal signs. This study presents data from 103 patients in whom bacterial meningitis was diagnosed. Neisseria meningitidis was the dominant pathogen of meningitis. We found a 2% case-fatality rate in children with bacterial meningitis and a 13% rate of sequelae among survivors: 7% hearing impairment and 7% neurological sequelae. Children with bacterial meningitis caused by Streptococcus pneumoniae and those with acute focal neurological symptoms tended to have the worst prognosis.

New therapies and vaccines for bacterial meningitis

Acute bacterial meningitis remains an important cause of morbidity and mortality worldwide. There have recently been major advances in the prevention of the major causes of bacterial meningitis following improvements in vaccinology. The success of immunisation against Haemophilus influenzae type b infection is being mirrored with serogroup C conjugated meningococcal vaccine and pneumococcal conjugate vaccine. However, there remain major challenges, notably, serogroup B meningococcal infection and shifts in epidemiology caused by vaccine introduction. In addition, much of the world's population is unvaccinated. Therefore, improvements in management of acute bacterial meningitis are vital. In this review we attempt to summarise important advances in both prevention and treatment of acute bacterial meningitis.

Bacterial meningitis: current controversies in approaches to treatment

Acute bacterial meningitis continues to be a disease with unacceptably high mortality and morbidity rates in both adults and children worldwide, despite advances in antibacterial therapy. Death or permanent disability occurs frequently. The causative organism varies with age, immune function and immunisation status. Infection with Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) is associated with the majority of cases, with Listeria monocytogenes and Streptococcus agalactiae being more prevalent pathogens at the extremes of age (<3 months or >50 years). Antibacterial resistance is an increasing problem, particularly in pneumococcal bacteria but increasingly in other organisms. The increasing prevalence of resistance of pneumococcus to penicillin and the cephalosporins complicates therapy and may have an important impact on treatment outcome. Increased understanding of the pathophysiology has allowed advances in diagnosis and therapy. The use of adjunctive corticosteroids remains controversial, but is probably beneficial in reducing neurological sequelae in children. In adults the evidence is less clear. Vaccination has virtually eradicated Hib meningitis in some countries. Recent introduction of a conjugate vaccine against serogroup C meningococci in the UK has caused a dramatic reduction in the incidence of invasive disease due to this organism. A 7-valent pneumococcal vaccine promises a similar reduction in the incidence of invasive pneumococcal disease. In the meantime, the emergence of widespread resistance of organisms to antibacterial agents, in particular among the common organisms causing bacterial meningitis, remains the biggest challenge in therapy.

Bacterial meningitis in aging adults

Bacterial meningitis remains a highly lethal disease in older adults, with mortality rates averaging >20% despite modern antibiotic therapy. In this population, more variable presentations are seen, with fewer patients manifesting fever, neck stiffness, and headache than among younger adults. In addition, many older adults (aged > or =60 years) may have other underlying diseases causing symptoms that may be confused with those of meningitis. The spectrum of etiologic bacterial organisms is more broad than that for a younger population, in part because of the increased frequency of severe underlying diseases and in part as a result of immunosenescence. Therapy is complicated by both the range of possible causative organisms and the increasing antibiotic resistance manifested by some. These difficulties, contrasted with the success of vaccination in the pediatric population, highlight the need for improved preventive strategies for older adults. This review outlines some key clinical points in the management of bacterial meningitis in the older adult.

The antibiotic and anti-inflammatory treatment of bacterial meningitis in adults: do we have to change our strategies in an era of increasing antibiotic resistance?

Community acquired bacterial meningitis remains a feared infection because of its high morbidity and mortality. During the last decade, the incidence and the microbial resistance patterns of pathogens causing bacterial meningitis have changed considerably. A sharp increase in meningococcal disease has been observed and meningitis caused by penicillin resistant Streptococcus pneumoniae emerged as a matter of major concern. Since pneumococcal resistance in Belgium to third generation cephalosporins remains rare and low level, addition of vancomycin to the initial empirical therapy including third generation cephalosporins is not yet necessary. However, the evolution of the resistance patterns of invasive S. pneumoniae should be followed very carefully. The emergence of penicillin resistant pneumococci also raises concern about the safety of adjuvant anti-inflammatory therapy with dexamethasone. Although there is a growing evidence suggesting a decrease of neurological complications after administration of adjuvant dexamethasone, this therapy may lower the already borderline penetration through the blood-brain barrier of the currently used antibiotics. This may result in therapeutic failure. We therefore presently do not advocate the routine use of dexamethasone in the therapy of adult bacterial meningitis.