Clinical outcomes of meningitis caused by Streptococcus pneumoniae in the era of antibiotic resistance

Global Case Fatality of Bacterial Meningitis During an 80-Year Period: A Systematic Review and Meta-Analysis

Importance

The impact of vaccination, antibiotics, and anti-inflammatory treatment on pathogen distribution and outcome of bacterial meningitis over the past century is uncertain.

Objective

To describe worldwide pathogen distribution and case fatality ratios of community-acquired bacterial meningitis.

Data Sources

Google Scholar and MEDLINE were searched in January 2022 using the search terms bacterial meningitis and mortality.

Study Selection

Included studies reported at least 10 patients with bacterial meningitis and survival status. Studies that selected participants by a specific risk factor, had a mean observation period before 1940, or had more than 10% of patients with health care-associated meningitis, tuberculous meningitis, or missing outcome were excluded.

Data Extraction and Synthesis

Data were extracted by 1 author and verified by a second author. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Random-effects models stratified by age (ie, neonates, children, adults), Human Development Index (ie, low-income or high-income countries), and decade and meta-regression using the study period's year as an estimator variable were used.

Main Outcome and Measure

Case fatality ratios of bacterial meningitis.

Results

This review included 371 studies performed in 108 countries from January 1, 1935, to December 31, 2019, describing 157 656 episodes. Of the 33 295 episodes for which the patients' sex was reported, 13 452 (40%) occurred in females. Causative pathogens were reported in 104 598 episodes with Neisseria meningitidis in 26 344 (25%) episodes, Streptococcus pneumoniae in 26 035 (25%) episodes, Haemophilus influenzae in 22 722 (22%), other bacteria in 19 161 (18%) episodes, and unidentified pathogen in 10 336 (10%) episodes. The overall case fatality ratio was 18% (95% CI, 16%-19%), decreasing from 32% (95% CI, 24%-40%) before 1961 to 15% (95% CI, 12%-19%) after 2010. It was highest in meningitis caused by Listeria monocytogenes at 27% (95% CI, 24%-31%) and pneumococci at 24% (95% CI, 22%-26%), compared with meningitis caused by meningococci at 9% (95% CI, 8%-10%) or H influenzae at 11% (95% CI, 10%-13%). Meta-regression showed decreasing case fatality ratios overall and stratified by S pneumoniae, Escherichia coli, or Streptococcus agalactiae (P < .001).

Conclusions and Relevance

In this meta-analysis with meta-regression, declining case fatality ratios of community-acquired bacterial meningitis throughout the last century were observed, but a high burden of disease remained.

Comparison of 16S Ribosomal RNA Targeted Sequencing and Culture for Bacterial Identification in Normally Sterile Body Fluid Samples: Report of a 10-Year Clinical Laboratory Review

As 16S ribosomal RNA (rRNA)-targeted sequencing can detect DNA from non-viable bacteria, it can be used to identify pathogens from clinical samples even in patients pretreated with antibiotics. We compared the results of 16S rRNA-targeted sequencing and culture for identifying bacterial species in normally sterile body fluid (NSBF): cerebrospinal, pericardial, peritoneal and pleural fluids. Over a 10-year period, a total of 312 NSBF samples were evaluated simultaneously using 16S rRNA-targeted sequencing and culture. Results were concordant in 287/312 (92.0%) samples, including 277 (88.8%) negative and 10 (3.2%) positive samples. Of the 16 sequencing-positive, culture-negative samples, eight showed clinically relevant isolates that included Fusobacterium nucleatum subsp. nucleatum, Streptococcus pneumoniae, and Staphylococcus spp. All these samples were obtained from the patients pretreated with antibiotics. The diagnostic yield of 16S rRNA-targeted sequencing combined with culture was 11.2%, while that of culture alone was 6.1%. 16S rRNA-targeted sequencing in conjunction with culture could be useful for identifying bacteria in NSBF samples, especially when patients have been pretreated with antibiotics and when anaerobic infection is suspected.

Impact of the 13-Valent Pneumococcal Conjugate Vaccine on Pneumococcal Meningitis in US Children

BACKGROUND

The impact of 13-valent pneumococcal conjugate vaccine (PCV13) on pneumococcal meningitis (PM) in US children is unknown. We compared the serotype distribution, antibiotic susceptibility, hospital course, and outcomes of children with PM 3 years before and 3 years after the introduction of PCV13.

METHODS

We identified patients ≤ 18 years of age with PM at 8 children's hospitals in the United States. Pneumococcal isolates were collected prospectively. Serotyping and antibiotic susceptibility were performed in a central laboratory. Clinical data were abstracted from medical records. Patients were divided into 3 subgroups: pre-PCV13 (2007-2009), transitional year (2010), and post-PCV13 (2011-2013). Categorical variables were analyzed by the χ(2) test and continuous variables by the Mann--Whitney U test.

RESULTS

During the study period, 173 of 1207 episodes (14%) of invasive pneumococcal disease were identified as PM; 76 of 645 (12%) were during 2007-2009 and 69 of 394 (18%) during 2011-2013 (50% increase; P = .03). The proportion of PCV13 serotype cases decreased from 54% in 2007-2009 to 27% in 2011-2013 (P = .001). Non-PCV13 serotype cases represented 73% of the isolates in 2011-2013. Isolates with ceftriaxone minimum inhibitory concentration ≥ 1 µg/mL decreased (13% to 3%) from 2007-2009 to 2011-2013 (P = .03). No significant differences were identified for hospital course or outcome, with the exception that a greater proportion of patients had subdural empyema and hemiparesis in 2011-2013.

CONCLUSIONS

After the introduction of PCV13, the number of cases of PM in children remained unchanged compared with 2007-2009, although the proportion of PCV13 serotypes decreased significantly. Serotype 19A continued to be the most common serotype in 2011-2013. Antibiotic resistance decreased significantly. Morbidity and case-fatality rate due to PM remain substantial.

Factors associated with ceftriaxone nonsusceptibility of Streptococcus pneumoniae: analysis of South African national surveillance data, 2003 to 2010

It is important to monitor β-lactam antimicrobial nonsusceptibility trends for Streptococcus pneumoniae to inform empirical treatment guidelines. In this study, we describe penicillin and ceftriaxone susceptibility trends using national laboratory-based pneumococcal surveillance data from 2003 to 2010. A sentinel enhanced-site patient subset (2009 to 2010) contributed to the risk factor and mortality analyses. We included 9,218 invasive pneumococcal disease (IPD) cases for trend analyses and 2,854 IPD cases for risk factor and mortality analyses. Overall, we detected no significant changes in penicillin (patients <5 years of age, P = 0.50; patients ≥ 5 years of age, P = 0.05) or ceftriaxone nonsusceptibility rates (patients <5 years of age, P = 0.21; patients ≥ 5 years of age, P = 0.60). Factors associated with ceftriaxone nonsusceptibility on multivariate analysis were an age of <5 years (<1 year of age: adjusted odds ratio [aOR], 2.87; 95% confidence interval [CI], 1.70 to 4.86; 1 to 4 years of age: aOR, 2.58; 95% CI, 1.53 to 4.35, versus 25 to 44 years of age), province (Gauteng [aOR, 2.46; 95% CI, 1.26 to 4.84], and Northern Cape [aOR, 4.52; 95% CI, 1.95 to 10.52] versus KwaZulu-Natal), β-lactam use within 24 h preceding admission (aOR, 2.52; 95% CI, 1.41 to 4.53), and 13-valent vaccine serotypes (aOR, 51.64; 95% CI, 7.18 to 371.71). Among patients ≥ 5 years of age with meningitis who were treated according to current guidelines, HIV-infected patients (aOR, 2.94; 95% CI, 1.32 to 6.54) and patients infected with ceftriaxone-nonsusceptible isolates (aOR, 3.17; 95% CI, 1.27 to 7.89) had increased mortality rates. Among children <5 years of age with meningitis, mortality was increased in HIV-infected patients (aOR, 3.04; 95% CI, 1.40 to 6.56) but not in those with ceftriaxone-nonsusceptible isolates. Penicillin and ceftriaxone nonsusceptibility remained stable over the study period. Ceftriaxone nonsusceptibility was associated with increased mortality among patients ≥5 years of age with meningitis. The introduction of a pneumococcal conjugate vaccine may reduce ceftriaxone-nonsusceptible meningitis.

Clinical observation of meningitis caused by penicillin-susceptible and -non-susceptibleStreptococcus pneumoniaein Taiwanese children

AIM

To compare differences between clinical features and outcome in bacterial meningitis caused by penicillin-susceptible Streptococcus pneumoniae (PSSP) with that caused by penicillin-non-susceptible Streptococcus pneumoniae (PNSP).

METHODS

All patients <18 yrs hospitalised with pneumococcal meningitis between January 1984 and December 2002 at Chang Gung Children's Hospital, Taipei were reviewed retrospectively.

RESULTS

There were 28 PNSP (63.6%) and 16 PSSP cases of meningitis eligible for the study. The incidence of PNSP meningitis increased significantly over the 8-yr period (p = 0.007). Age <4 yrs (78.6% vs 50%), a lower initial white blood count (mean 11.7 vs 19.9 x10(9)/L), admission to the intensive care unit (70.4% vs 50%) and mortality (28.6% vs 6.3%) were more common in the PNSP group. However, the only significant finding was a lower proportion of polymorphic neutrophils in the CSF of the PNSP meningitis group (p = 0.04).

CONCLUSIONS

There was an increase in PNSP isolates from patients with meningitis over the 8-yr study period. No major differences were observed in clinical or laboratory features or outcome between the PSSP and PNSP groups.

Adjunctive daptomycin attenuates brain damage and hearing loss more efficiently than rifampin in infant rat pneumococcal meningitis

Exacerbation of cerebrospinal fluid (CSF) inflammation in response to bacteriolysis by beta-lactam antibiotics contributes to brain damage and neurological sequelae in bacterial meningitis. Daptomycin, a nonlytic antibiotic acting on Gram-positive bacteria, lessens inflammation and brain injury compared to ceftriaxone. With a view to a clinical application for pediatric bacterial meningitis, we investigated the effect of combining daptomycin or rifampin with ceftriaxone in an infant rat pneumococcal meningitis model. Eleven-day-old Wistar rats with pneumococcal meningitis were randomized to treatment starting at 18 h after infection with (i) ceftriaxone (100 mg/kg of body weight, subcutaneously [s.c.], twice a day [b.i.d.]), (ii) daptomycin (10 mg/kg, s.c., daily) followed 15 min later by ceftriaxone, or (iii) rifampin (20 mg/kg, intraperitoneally [i.p.], b.i.d.) followed 15 min later by ceftriaxone. CSF was sampled at 6 and 22 h after the initiation of therapy and was assessed for concentrations of defined chemokines and cytokines. Brain damage was quantified by histomorphometry at 40 h after infection and hearing loss was assessed at 3 weeks after infection. Daptomycin plus ceftriaxone versus ceftriaxone significantly (P < 0.04) lowered CSF concentrations of monocyte chemoattractant protein 1 (MCP-1), MIP-1α, and interleukin 6 (IL-6) at 6 h and MIP-1α, IL-6, and IL-10 at 22 h after initiation of therapy, led to significantly (P < 0.01) less apoptosis, and significantly (P < 0.01) improved hearing capacity. While rifampin plus ceftriaxone versus ceftriaxone also led to lower CSF inflammation (P < 0.02 for IL-6 at 6 h), it had no significant effect on apoptosis and hearing capacity. Adjuvant daptomycin could therefore offer added benefits for the treatment of pediatric pneumococcal meningitis.

Increased risk of death in human immunodeficiency virus-infected children with pneumococcal meningitis in South Africa, 2003-2005

BACKGROUND

Pneumococcal disease is a major global cause of morbidity and mortality. This study evaluated risk factors for mortality in children with pneumococcal meningitis and other invasive pneumococcal diseases (IPD).

METHODS

The study population included patients <15 years of age with laboratory-confirmed IPD and available outcome data between January 1, 2003 and December 31, 2005 as reported to a national laboratory-based surveillance program. Meningitis was defined by having pneumococcus identified from cerebrospinal fluid culture, while other IPD included patients with pneumococci identified from other normally sterile site specimens. Risk factors for mortality were evaluated using multivariable logistic regression.

RESULTS

A total of 2251 patients with IPD were reported from sentinel sites: 581 with laboratory-confirmed meningitis and 1670 with other IPD. The case-fatality ratio was 35% (205/581) among meningitis cases and 18% (300/1670) among other IPD cases (P < 0.001). Among individuals with available human immunodeficiency virus (HIV) status data, HIV coinfection was less likely among patients with meningitis compared with other IPD (74% [244/328] vs. 82% [880/1067] P < 0.001). On multivariable analysis, HIV-infected status (odds ratio [OR]: 5.34, 95% confidence interval [CI]: 2.32-12.29), Pitt bacteremia score ≥4 (OR: 3.08, 95% CI: 1.21-7.83) and age group <1 year (OR: 2.58, 95% CI: 1.21-5.51) were independent predictors of death among patients with meningitis. Among children with other IPD, malnutrition was an independent predictor of death while HIV infection was not independently associated with increased risk of death.

CONCLUSIONS

Pneumococcal meningitis is associated with a high case-fatality ratio among South African children and this is increased by HIV coinfection. Increasing access to antiretroviral therapy and a catch-up program for pneumococcal conjugate vaccine among HIV-infected and malnourished children could reduce this excess mortality.

Clinical outcome of pneumococcal meningitis during the emergence of pencillin-resistant Streptococcus pneumoniae: an observational study

Background

Prior to the availability of generic third-generation cephalosporins, penicillins were widely used for treatment of pneumococcal meningitis in developing countries despite concerns about rising levels of penicillin resistance among pneumococcal isolates. We examined the impact of penicillin resistance on outcomes of pneumococcal meningitis over a ten year period in an infectious diseases hospital in Brazil.

Methods

Clinical presentation, antimicrobial therapy and outcomes were reviewed for 548 patients with culture-confirmed pneumococcal meningitis from December, 1995, to November, 2005. Pneumococcal isolates from meningitis patients were defined as penicillin-resistant if Minimum Inhibitory Concentrations for penicillin were greater than 0.06 μg/ml. Proportional hazards regression was used to identify risk factors for fatal outcomes.

Results

During the ten-year period, ceftriaxone replaced ampicillin as first-line therapy for suspected bacterial meningitis. In hospital case-fatality for pneumococcal meningitis was 37%. Of 548 pneumococcal isolates from meningitis cases, 92 (17%) were resistant to penicillin. After controlling for age and severity of disease at admission, penicillin resistance was associated with higher case-fatality (Hazard Ratio [HR], 1.62; 95% Confidence Interval [CI], 1.08-2.43). Penicillin-resistance remained associated with higher case-fatality when initial therapy included ceftriaxone (HR, 1.68; 95% CI 1.02-2.76).

Conclusions

Findings support the use of third generation cephalosporin antibiotics for treatment of suspected pneumococcal meningitis even at low prevalence of pneumococcal resistance to penicillins.

Pathophysiology and treatment of bacterial meningitis

Bacterial meningitis is a medical emergency requiring immediate diagnosis and immediate treatment. Streptococcus pneumoniae and Neisseria meningitidis are the most common and most aggressive pathogens of meningitis. Emerging antibiotic resistance is an upcoming challenge. Clinical and experimental studies have established a more detailed understanding of the mechanisms resulting in brain damage, sequelae and neuropsychological deficits. We summarize the current pathophysiological concept of acute bacterial meningitis and present current treatment strategies.

Reduced susceptibility to penicillin among pneumococci causing invasive infection in children - Canada, 1991 to 1998

OBJECTIVE

To determine, over time, the rate and serotypes of pneumococci with reduced penicillin susceptibility obtained from children with invasive infection.

DESIGN

Active, hospital-based, multicentre surveillance spanning from 1991 to 1998.

SETTING

Eleven Canadian tertiary care paediatric facilities located from coast to coast.

POPULATION STUDIED

1847 children with invasive pneumococcal infection whose isolates (from a normally sterile site) were available for serotyping and standardized testing for penicillin susceptibility at the National Centre for Streptococcus.

MAIN RESULTS

The prevalence of reduced penicillin susceptibility increased from 2.5% of 197 cases in 1991 to 13.0% of 276 cases in 1998. In the latter year, 8.7% of isolates had intermediate level resistance, and 4.3% had high level resistance. Since they were first detected in 1992, strains with high level resistance have been encountered only sporadically at most centres, but by 1998, all centres but two had encountered examples. Of 40 isolates with high level resistance and 101 isolates with intermediate level resistance, serotypes matched those included in new seven-valent conjugate vaccines for children in 97.5% and 79.2% of cases, respectively.

CONCLUSIONS

Pneumococci with reduced susceptibility to penicillin are increasing in frequency across Canada among children with invasive infection. The Immunization Monitoring Program, Active data indicate that new conjugate vaccines could help to curb infections due to pneumococci with reduced susceptibility to penicillin but are unlikely to control completely the problem of antibiotic resistance.

Invasive pneumococcal disease in children prior to implementation of the conjugate vaccine in the Zurich region, Switzerland

OBJECTIVE

To describe symptoms, disease manifestations and outcome of invasive pneumococcal disease in children prior to implementation of the pneumococcal vaccine.

PATIENTS AND METHODS

Analysis of children younger than 16 years of age with invasive pneumococcal disease (IPD; n = 119). Children with culture-confirmed IPD, without underlying illness at risk for invasive disease, were included.

RESULTS

IPD in 90 children (age: median 2, mean 3.2 years) included 15 with meningitis, 16 with septicaemia, 14 with bacteraemia, 24 with pneumonia and 21 with skin, bone and joint infections. Symptoms of IPD most often described were fever and gastrointestinal symptoms (abdominal pain, vomiting, or diarrhoea), and coughing. More than 90% of children with pneumonia were coughing. Most importantly, clinical signs significantly predictive for severe IPD included tachycardia for sepsis, tachypnea for pneumonia, and meningeal signs for meningitis. Leukocyte, neutrophil and platelet counts were lower and C-reactive protein concentrations were higher on admission in children with complicated than in children with uncomplicated IPD but, due to wide overlap of these numbers, the difference was not of prognostic help to predict clinical course and outcome. Overall, 40% of children with IPD manifested complications and IPD showed a mortality rate of 6.6%.

CONCLUSIONS

IPD is a serious disease with a high complication rate and mortality. The clinical signs tachycardia, tachypnea, and meningism were highly predictive for severe IPD. The initial clinical presentation and laboratory evaluation were mostly unpredictable with respect to complications and outcome in contrast to the clinical signs.

The risk of sequelae due to pneumococcal meningitis in high-income countries: a systematic review and meta-analysis

OBJECTIVES

To determine the risk of various kinds of sequelae in survivors of meningitis due to Streptococcus pneumoniae, as well as the influence of co-factors such as study design, study population and treatment on this risk.

METHODS

MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from 1 September 1991 to 18 June 2009 for original articles on pneumococcal meningitis sequelae. Prevalence of sequelae was pooled using random effects meta-analysis. Studies were appraised for the influence of referral bias, external validity of study populations, testing procedure and publication bias.

RESULTS

Data were extracted from 63 studies involving 3408 pneumococcal meningitis survivors. The pooled prevalence of any reported sequelae from 48 studies was 31.7% (95% confidence interval 27.2-36.3%) using a random effects model (Cochran-Q = 277, p < 0.01). Differences in studies due to design, study population and treatment were not significant. The pooled prevalence of hearing loss, seizures, hydrocephalus, spasticity/paresis, cranial nerve palsies and visual impairment was 20.9% (17.1-24.7%), 6.5% (3.3-9.7%), 6.8% (3.3-10.2%), 8.7% (6.4-11.0%), 12.2% (5.3-19.1%) and 2.4% (0-5.7%) respectively.

CONCLUSIONS

The burden of sequelae due to pneumococcal meningitis remains high in the reviewed studies.

[First and second line antibiotic therapy for bacterial meningitis in infants and children]

The potential severity of meningitis in infants and children requires an optimized initial empirical therapy, mainly based on direct cerebro spinal fluid (CSF) examination, and rapid therapeutic adaptation according to bacterial identification and susceptibility. Combination treatment including cefotaxim (300 mg/kg per day) or ceftriaxone (100mg/kg per day) and vancomycine (60 mg/kg per day) remains the standard first line if pneumococcal meningitis cannot be ruled out. A simple treatment with third generation cephalosporin can be used for Neisseria meningitidis or Haemophilus influenzae meningitis, aminoglycosides must be added in case of Enterobacteriacae, mainly before 3 months of age. Second line antibiotic therapy is adapted according to the clinical and bacteriological response on Day 2. When the minimal inhibitory concentration (MIC) of pneumococcal strain is less than 0.5mg/L, third generation cephalosporin should be continued alone for a total of 10 days. In other cases, a second lumbar puncture is necessary and the initial regimen, with or without rifampicin combination, should be used for 14 days. Amoxicillin during 3 weeks, associated with gentamycin or cotrimoxazole is recommended for listeriosis.

[Treatment of community acquired bacterial meningitis, after microbiological identification]

INTRODUCTION

Are the 1996 SPILF consensus conference recommendations on bacterial meningitis (BM) still adequate?

OBJECTIVE

The literature published after 1996 was analyzed and the reviewers summarized the available data on antibiotic treatment once BM microbiological diagnosis made or strongly suspected.

METHOD

A review was made using PubMed, 10,015 references were examined. Only articles published after 1997 were analyzed.

RESULTS

No study allowed to recommend other regimens than those previously recommended in 1996, in case of meningococcal or pneumococcal infection: 3rd generation cephalosporin or amoxicillin, combined with vancomycin in case of penicillin-intermediate or resistant pneumococcus. In some cases, alternatives are possible, in case of pneumococcal infection: meropenem or antipneumococcal fluoroquinolone were recommended by US guidelines. New antibiotics available on the market were tested using experimental pneumococcal meningitis models: daptomycin and ertapenem seemed to be useful but linezolid was not. Among the antibiotic combinations tested, ceftriaxone+rifampicine demonstrated a better efficacy than ceftriaxone+vancomycin. There was not contributive published data on the length of treatment for bacterial meningitis.

CONCLUSION

No assessed arguments could be found to modify previous guidelines. In case of problem with penicillin-resistant pneumococci, penem or a combination using ceftriaxone and rifampicin may be used.

Clinical and economic burden of antimicrobial resistance

Knowledge of the clinical and economic impact of antimicrobial resistance is useful to influence programs and behavior in healthcare facilities, to guide policy makers and funding agencies, to define the prognosis of individual patients and to stimulate interest in developing new antimicrobial agents and therapies. There are a variety of important issues that must be considered when designing or interpreting studies into the clinical and economic outcomes associated with antimicrobial resistance. One of the most misunderstood issues is how to measure cost appropriately. Although imperfect, existing data show that there is an association between antimicrobial resistance in Staphylococcus aureus, enterococci and Gram-negative bacilli and increases in mortality, morbidity, length of hospitalization and cost of healthcare. Patients with infections due to antimicrobial-resistant organisms have higher costs (US $6,000-30,000) than do patients with infections due to antimicrobial-susceptible organisms; the difference in cost is even greater when patients infected with antimicrobial-resistant organisms are compared with patients without infection. Given limited budgets, knowledge of the clinical and economic impact of antibiotic-resistant bacterial infections, coupled with the benefits of specific interventions targeted to reduce these infections, will allow for optimal control and improved patient safety. In this review, the authors discuss a variety of important issues that must be considered when designing or interpreting studies of the clinical and economic outcomes associated with antimicrobial resistance. Representative literature is reviewed regarding the associations between antimicrobial resistance in specific pathogens and adverse outcomes, including increased mortality, length of hospital stay and cost.

Pneumococcal meningitis in Taiwanese children: emphasis on clinical outcomes and prognostic factors

Pneumococcal meningitis causes high morbidity or mortality in childhood despite the progress in medicine. Children with pneumococcal meningitis were identified and retrospectively reviewed. Forty-nine children were eligible, with mortality in 24.5% of all and neurological sequelae in 40.5% of survivors. In the analysis of clinical profiles, ventilator support (p = 0.001), septic shock (p < 0.001), multiple organ failure (p < 0.001) and lower cerebrospinal fluid (CSF) leukocyte count (p = 0.001) were more frequently found in non-survivors. Besides, CSF protein (p = 0.006) was higher in survivors with neurological sequelae. Initial dexamethasone usage and disease severity did not affect the occurrence of neurological sequelae. Multivariate logistic regression analysis revealed that CSF leukocyte count <or=200 mm(-3) (p = 0.013) and protein level >or=330 g l(-1) (p = 0.022) were significantly risk factors associated with poor outcomes, and physicians should be cautious if such conditions occur.

Mortalité par méningites à pneumocoque chez l'enfant. Facteurs pronostiques à propos d'une série de 73 observations

OBJECTIVE

Despite advances in antibiotic therapy strategies and pediatric intensive care, prognosis of Streptococcus pneumoniae meningitis remains very poor. To determine the factors associated with hospital mortality of children with pneumococcal meningitis.

METHODS

We conducted a retrospective study of 73 cases of childhood pneumococcal meningitis admitted in 4 teaching hospitals in the center of Tunisia during a 8-year period (1995-2002).

RESULTS

Hospital mortality was 13.7% (10 of 71 patients), and neurologic sequela were observed in 34.5% of survivors. Based on univariable analysis, five variables were associated with the outcome: Pediatric Risk of Mortality score (p < 0.001), coma (p=0.0009), use of mechanical ventilation (p=0.0001), convulsions (p = 0.0449), and shock (p=0.0085). In multivariable analysis, only 2 factors were independently associated with in-hospital mortality: Pediatric Risk of Mortality score and the use of mechanical ventilation. 11.8% of pneumococcal isolates were intermediate and resistant to penicillin. Non-susceptible pneumococcus strains to penicillin and the use of steroids were not associated significantly with the mortality rate.

CONCLUSIONS

Pneumococcal meningitis remains a devastating childhood disease. Two variables were independently associated with the in-hospital death in our series (high Pediatric Risk of Mortality score, and the use of mechanical ventilation). According to these data we may recommend the inclusion of vaccination against streptococcus pneumonia in the children's immunization program in Tunisia.

The burden of pneumococcal disease in the Canadian population before routine use of the seven-valent pneumococcal conjugate vaccine

BACKGROUND

In the United States, implementation of the seven-valent conjugate vaccine into childhood immunization schedules has had an effect on the burden of pneumococcal disease in all ages of the population. To evaluate the impact in Canada, it is essential to have an estimate of the burden of pneumococcal disease before routine use of the vaccine.

METHODS

The incidence and costs of pneumococcal disease in the Canadian population in 2001 were estimated from various sources, including published studies, provincial databases and expert opinion.

RESULTS

In 2001, there were 565,000 cases of pneumococcal disease in the Canadian population, with invasive infections representing 0.7%, pneumonia 7.5% and acute otitis media 91.8% of cases. There were a total of 3000 deaths, mainly as a result of pneumonia and largely attributable to the population aged 65 years or older. There were 54,330 life-years lost due to pneumococcal disease, and 37,430 quality-adjusted life-years lost due to acute disease, long-term sequelae and deaths. Societal costs were estimated to be $193 million (range $155 to $295 million), with 82% borne by the health system and 18% borne by families. Invasive pneumococcal infections represented 17% of the costs and noninvasive infections represented 83%, with approximately one-half of this proportion attributable to acute otitis media and myringotomy.

CONCLUSIONS

The burden of pneumococcal disease before routine use of the pneumococcal conjugate vaccine was substantial in all age groups of the Canadian population. This estimate provides a baseline for further analysis of the direct and indirect impacts of the vaccine.

Detrimental role of delayed antibiotic administration and penicillin-nonsusceptible strains in adult intensive care unit patients with pneumococcal meningitis: the PNEUMOREA prospective multicenter study

OBJECTIVE

To identify factors associated with mortality and morbidity among adults admitted to intensive care units (ICUs) for pneumococcal meningitis, particularly the impact of delayed antibiotic administration.

DESIGN

We conducted a prospective, multicenter, observational study of 156 consecutive adults hospitalized for pneumococcal meningitis. We analyzed parameters associated with 3-month survival.

SETTING

Fifty-six medical and medical-surgical ICUs in France.

INTERVENTION

None.

RESULTS

Of the 148 strains isolated, 56 (38%) were nonsusceptible to penicillin G. At 3 months after ICU admission, the mortality rate was 33% (51/156), and 34% of survivors (36/105) had neurologic sequelae. Multivariate analysis identified three variables as independently associated with 3-month mortality: Simplified Acute Physiology Score II (odds ration [OR], 1.12; 95% confidence interval [CI], 1.072-1.153; p = .002); isolation of a nonsusceptible strain (OR, 6.83; 95% CI, 2.94-20.8; p < 10(-4)), and an interval of >3 hrs between hospital admission and administration of antibiotics (OR, 14.12; 95% CI, 3.93-50.9; p < 10(-4)). In contrast, a cerebrospinal fluid leukocyte count >10(3) cells/microL had a protective effect (OR, 0.30; 95% CI, 0.10-0.944; p = 0.04).

CONCLUSIONS

Independent of severity at the time of ICU admission, isolation of penicillin-nonsusceptible strains and a delay in antibiotic treatment following admission were predictors of mortality among patients with pneumococcal meningitis.

The relationship between antimicrobial resistance and patient outcomes: mortality, length of hospital stay, and health care costs

There is an association between the development of antimicrobial resistance in Staphylococcus aureus, enterococci, and gram-negative bacilli and increases in mortality, morbidity, length of hospitalization, and cost of health care. For many patients, inadequate or delayed therapy and severe underlying disease are primarily responsible for the adverse outcomes of infections caused by antimicrobial-resistant organisms. Patients with infections due to antimicrobial-resistant organisms have higher costs (approximately 6,000-30,000 dollars) than do patients with infections due to antimicrobial-susceptible organisms; the difference in cost is even greater when patients infected with antimicrobial-resistant organisms are compared with patients without infection. Strategies to prevent nosocomial emergence and spread of antimicrobial-resistant organisms are essential.

Risk factors for mortality in Paraguayan children with pneumococcal bacterial meningitis

BACKGROUND

Over the last decade Streptococcus pneumoniae has emerged as the most common bacterial pathogen for meningitis in all age groups, beyond the neonatal period.

OBJECTIVE

To determine the epidemiological and clinical characteristics; and risk factors for mortality of pneumoccocal meningitis in children in a developing transitional country.

MATERIALS AND METHODS

A retrospective study that included patients<15 years of age admitted at the Instituto de Medicina Tropical of Paraguay, from January 1990 until December 2003 with the diagnosis of bacterial meningitis caused by S. pneumoniae. Clinical and laboratory data were collected and analysed in order to identify risk factors associated with morbidity and mortality outcomes of this infection.

RESULTS

Seventy-two patients (between the ages of 35 days and 14 years) were identified. Forty-two per cent of patients had seizures prior to or at the time of admission, 36% were admitted in a comatose state, and 19% with shock. Mortality was 33% (24/72), and 18% of the survivors (11/60) developed severe sequelae. Upon admission, the following variables were strongly correlated with mortality: age<12 months (P=0.007), the presence of seizures (P=0.0001) or development of seizures 48 h after admission (P=0.01), a cerebrospinal fluid (CSF) glucose level of <10 mg/dl (P=0.01), CSF albumin>200 mg/dl (P=0.0003), an absolute blood neutrophil count<2000/mm3 (P=0.006) and a haemoglobin value of <9 g/dl (P=0.0001).

CONCLUSIONS

This study confirms the high morbidity and mortality associated with S. pneumoniae meningitis in Paraguay. Certain clinical parameters and laboratory findings in blood and CSF at the time of admission could be used as predictors for mortality or severe sequelae among survivors.

Clinical presentation and prognostic factors of Streptococcus pneumoniae meningitis according to the focus of infection

Background

We conducted a nationwide study in Denmark to identify clinical features and prognostic factors in patients with Streptococcus pneumoniae according to the focus of infection.

Methods

Based on a nationwide registration, clinical information's was prospectively collected from all reported cases of pneumococcal meningitis during a 2-year period (1999–2000). Clinical and laboratory findings at admission, clinical course and outcome of the disease including follow-up audiological examinations were collected retrospectively. The focus of infection was determined according to the clinical diagnosis made by the physicians and after review of the medical records.

Results

187 consecutive cases with S. pneumoniae meningitis were included in the study. The most common focus was ear (30%), followed by lung (18%), sinus (8%), and other (2%). In 42% of cases a primary infection focus could not be determined. On admission, fever and an altered mental status were the most frequent findings (in 93% and 94% of cases, respectively), whereas back rigidity, headache and convulsion were found in 57%, 41% and 11% of cases, respectively. 21% of patients died during hospitalisation (adults: 27% vs. children: 2%, Fisher Exact Test, P < 0.001), and the causes of death were due to neurological – and systemic complications or the combination of both in 8%, 5% and 6% of cases, respectively. Other causes (e.g. gastrointestinal bleeding, incurable cancer) accounted for 2% of cases. 41% of survivors had neurological sequelae (hearing loss: 24%, focal neurological deficits: 16%, and the combination of both: 1%). The mortality varied with the focus of the infection (otogenic: 7%, sinusitic: 33%, pneumonic: 26%, other kind of focus: 50%, no primary infection focus: 21%, Log rank test: P = 0.0005). Prognostic factors associated with fatal outcome in univariate logistic regression analysis were advanced age, presence of an underlying disease, history of headache, presence of a lung focus, absence of an otogenic focus, having a CT-scan prior to lumbar puncture, convulsions, requirement of assisted ventilation, and alterations in various CSF parameters (WBC <500 cells/μL, high protein levels, glucose levels<1 mmol/L, low CSF/blood glucose levels), P < 0.05. Independent prognostic factor associated with fatal outcome in multivariate logistic regression analysis was convulsions (OR: 4.53, 95%CI: (1.74–11.8), p = 0.002), whereas presence of an otogenic focus was independently associated with a better survival (OR: 6.09, 95%CI: (1.75–21.2), P = 0.005).

Conclusion

These results emphasize the prognostic importance of an early recognition of a predisposing focus to pneumococcal meningitis.

Pneumococcal meningitis in a pediatric intensive care unit: prognostic factors in a series of 49 children

BACKGROUND

Despite advances in antibiotic therapy strategies and in pediatric intensive care, prognosis of Streptococcus pneumoniae meningitis remains very poor. However, few prognostic studies have been published, especially in pediatric populations.

METHODS

We conducted a prognostic study to determine the factors associated with hospital mortality of 49 children admitted in a single pediatric intensive care unit during a 12-yr period (1990-2002).

RESULTS

Hospital mortality was 49% (24 of 49 patients), and neurologic sequels were observed in 47% of survivors. Among them, 90% had permanent sensory deafness. Based on univariable analyses, seven variables were associated with the outcome: Pediatric Risk of Mortality II score (p = .000005), Glasgow Coma Score of >8 (p = .001), use of mechanical ventilation (p = .001), platelet count (p = .007), white blood cells count (p = .002), cerebrospinal fluid glucose level (p = .02), and lack of corticosteroids use (p = .02). In multivariable analysis, only three factors were independently associated with in-hospital mortality: Pediatric Risk of Mortality II score (hazard ratio, 1.13; 95% confidence interval, 1.06-1.20; p = .0002), platelets count of >200 x 10/L (hazard ratio, 0.25; 95% confidence interval, 0.08-0.81; p = .021) and white blood cell count above 5 x 10/L (hazard ratio, 0.31; 95% confidence interval, 0.11-0.87; p = .026).

CONCLUSIONS

S. pneumoniae meningitis remains a devastating childhood disease in developed countries. Three variables were independently associated with the in-hospital death in our series-high Pediatric Risk of Mortality II score, low white blood cells count, and low platelet count-reflecting the main importance of severe sepsis and neurologic presentation in establishing the prognosis of these patients.

Antimicrobial resistance in respiratory tract pathogens

Antimicrobial resistance has been a problem ever since the introduction of antimicrobial agents 60 years ago. Today, this problem is increasing so rapidly that the end of the antimicrobial era is being predicted. The increasing problems caused by antimicrobial resistance can be illustrated by those seen in bacterial pathogens that cause community acquired respiratory tract infections, which are among the most common and important infections seen by clinicians. Bacterial pathogens causing community acquired respiratory tract infections have a number of resistance mechanisms such as beta-lactamases. Recognition of these resistance mechanisms allows them to be targeted, such as with beta-lactamase inhibitors. Newly recognized resistance mechanisms such as efflux may also be targeted in the future.

Antimicrobial susceptibility of invasive isolates of Streptococcus pneumoniae in Ireland

Between January 1999 and June 2002, 646 invasive isolates of Streptococcus pneumoniae were collected in Ireland. MICs of penicillin, ciprofloxacin, cefotaxime, moxifloxacin and linezolid were determined by Etest methodology. Eighty-seven (13.5%) isolates showed intermediate resistance to penicillin, while seven (1.1%) showed high-level resistance. Eighty-seven (13.5%) isolates were resistant to erythromycin, but all isolates were susceptible to cefotaxime, moxifloxacin and linezolid. The prevalence of pneumococcal isolates non-susceptible to penicillin in Ireland is worryingly high, but currently there are alternative agents available to treat invasive infection.

Antibiotic resistant infections due to Streptococcus pneumoniae: impact on therapeutic options and clinical outcome

PURPOSE OF REVIEW

Streptococcus pneumoniae is a major cause of morbidity and mortality in the pediatric population. The development of increasing resistance to multiple classes of antibiotics is making treatment of infections due to this organism much more difficult. The ultimate impact of high-level antibiotic resistance on therapeutic options and clinical outcomes of various pneumococcal infections is unclear and remains to be determined. Use of the conjugate pneumococcal vaccine has markedly decreased invasive pneumococcal disease in children under 5 years of age; however, its impact on decreasing antibiotic resistance is currently unknown.

RECENT FINDINGS

Studies suggest that response to therapy and clinical outcome of infections due to pneumococcal isolates with intermediate resistance to the beta-lactam antibiotics is no different from that of infections due to susceptible isolates. However, evidence is accumulating that infections caused by highly resistant pneumococcal isolates are associated with higher rates of treatment failure and mortality than infections due to susceptible strains.

SUMMARY

Use of a conjugate pneumococcal vaccine in conjunction with educational intervention programs that promote appropriate and judicious antibiotic use is a safe and effective means of decreasing the prevalence of pneumococcal disease in the pediatric population, decreasing the use of broad-spectrum antibiotic agents and potentially decreasing the amount of antibiotic resistance currently being seen.

Health care resource utilization associated with treatment of penicillin-susceptible and -nonsusceptible isolates of Streptococcus pneumoniae

Despite failure to correlate in vitro susceptibility with clinical outcomes for respiratory tract infections and bacteremia, resistance affects management of patients with pneumococcal infections. The economic impact of resistance among pneumococci has not been evaluated. We conducted a single-center, retrospective, observational, cohort study of hospitalized patients infected with Streptococcus pneumoniae isolated from blood or a respiratory source between January 1, 1995, and December 31, 1998. Data were collected for 36 days surrounding the day that the first positive culture was collected. Patients were grouped according to isolate penicillin-susceptibility profile [susceptible minimum inhibitory concentration (MIC) < or = 0.06 microg/ml, nonsusceptible MIC > or = 0.125 microg/ml), and data were analyzed with respect to health care resource utilization patterns. Of 231 patients identified, 142 and 89 had susceptible and nonsusceptible isolates, respectively. Groups were similar with respect to demographics and comorbidities, except that patients infected with a nonsusceptible isolate were more likely to have the isolate obtained from a respiratory source and to have a history of recent antibiotic therapy. No difference was noted with respect to clinical outcome; however, patients infected with a nonsusceptible isolate had a longer median stay (14 vs 10 days, p<0.05). They also had significantly higher total median costs (1600 dollars, 95% confidence interval 257-2943 dollars) due to room and nursing services. Infections caused by penicillin-nonsusceptible pneumococci were not associated with a worse outcome in hospitalized patients but were associated with increased cost of care.

Exploring the pathogenesis of necrotizing fasciitis due to Streptococcus pneumoniae

Monobacterial necrotizing fasciitis is a rare form of soft tissue infection usually caused by the group A beta-hemolytic Streptococcus. Soft tissue infection is an uncommon clinical manifestation of invasive disease due to Streptococcus pneumoniae. We describe 3 cases of pneumococcal necrotizing fasciitis and explore potential pathogen-specific mechanisms of pathogenesis. The clinical characteristics of necrotizing fasciitis due to S. pneumoniae and group A beta-hemolytic Streptococcus appear to overlap. The similarities include predominant occurrence in elderly adults with underlying chronic illness, predilection for lower extremity infection, progression to toxic shock-like syndrome and a high case fatality rate. No DNA fragments corresponding to speA, speB or speC were amplified by PCR from the 3 pneumococcal isolates. Western immunoblot revealed no evidence of SpeA, SpeB or SpeC protein expression. Evaluation for protease production and cytotoxicity was unrevealing. The similar clinical presentation of pneumococcal necrotizing fasciitis to the disease caused by the group A beta-hemolytic Streptococcus has important therapeutic implications. The molecular mechanisms underlying the pathogenesis are unclear. Prospective population-based studies are required to define the epidemiology of this infection.

[Rhône-Alpes observatory of Streptococcus pneumoniae in 1999: 35 cases of meningitis]

In 1999, in Rhône-Alpes region, in a survey of resistance to antibiotics of Streptococcus pneumoniae, 35 cases of meningitis were observed. A retrospectic questionnary was sent to each participant. MICs to Penicillin, Amoxicillin and Cefotaxime were determined with ATB-PNEUMO gallery or E-test and by disk diffusion for the other antibiotics. The results were interpreted according to the recommendations of the CA-SFM. Mean age was 38.1 years (range : 1 month -78 years) and sex-ratio 2/5. Eight patients had previously received antibiotics, 22 patients had risk factors and 23 were transferred in intensive care unit. The patients received C3G + glycopeptide in 15 of 16 children and in 13/19 adults according to the consensus recommendations. Diagnostic was made on the direct examination of CSF in 83%, and blood cultures was positive in 74.3% of cases. The percentage of PRP was 48.6% with 17.1% of intermediate-amoxicilline and 14.3% intermediate-cefotaxime strains. Resistance to trimethoprim-sulfamethoxazole was 45.7%, to chloramphenicol 30% and to fosfomycin 6.9%. All the strains were susceptible to rifampicin and vancomycin. Among the 17 PRP strains, 7 were belonging to serotype 6 (6 in children). The clinical outcome was fatal in 7 male cases (20%), without risk factors in 3 children and 6 of 7 strains were susceptible to penicillin. Six patients (17%) had auditive and/or neurologic sequellaes. This study shows that nearly 50% of strains isolated in meningitis, in Rhône-Alpes region, were not susceptible to penicillin, and confirms the frequency of sequellaes while the mortality is not related with the resistance of strains to the antibiotics.

[Pneumococcal meningitis and resistant bacteria]

The emergence of resistance has imposed a modification of the protocols for the treatment of Streptococcus pneumoniae (S pneumoniae) bacterial meningitis. Amoxicillin is no longer adapted. As resistance to C3G appeared, a synergistic effect of an association C3G + vancomycine was demonstrated. Thus currently this association should be recommended in any case of meningitis supposedly due to S pneumoniae. The treatment is then modified according to the evolution and the minimal inhibition concentration (MIC) of the bacteria. The strains carrying a high level of resistance to cephalosporin (MIC > or = 4 micrograms ml-1) or tolerant to vancomycine may cause a therapeutic failure despite an increase of the dosage of cephalosporin. Rifampicin, fosfomycine, or imipenem (despite its risk of convulsions), may represent alternative options, as long as we do not have safe quinolones active on resistant strains of S. pneumoniae. Dexamethasone has been formerly implicated in the relapse of pneumococcal meningitis. Furthermore, its use is questionable since no evidence of a therapeutic benefit has been clearly demonstrated. As a consequence of the resistance phenomenon the management of S. pneumoniae meningitis must include particular measures: at least resistance to penicillin must be checked by the oxacilline disk and the MIC to C3G must be measured by E test; aCSF sample should be obtained between 36 and 48 hours following the beginning of the treatment to check its sterilization. All recent studies have shown a similar prognosis of meningitis due to resistant S. pneumoniae as compared to those due to sensitive strains. However, these data should be interpreted with caution since in these studies, pneumococcus resistant to cephalosporin (the real problem) are not separated from those only resistant to penicillin. Furthermore, presently, the incidence of strains highly resistant to cephalosporin is still low. The new conjugated vaccine against pneumococcus should change the situation if its ability to prevent the circulation of resistant strains is confirmed.

Outcome of penicillin-nonsusceptible Streptococcus pneumoniae meningitis: a nested case-control study

BACKGROUND

There are few data comparing the clinical features, management and outcome of penicillin-nonsusceptible (PNSP) meningitis patients with penicillin-susceptible (PSSP) meningitis patients.

METHODS

We performed a retrospective, nested case-control study comparing cases with PNSP meningitis with controls with PSSP meningitis obtained from the Immunization Monitoring Program, Active (IMPACT) cross-Canada surveillance study of invasive infections.

RESULTS

There were 30 PNSP meningitis cases (10.1% of total) and 45 PSSP meningitis controls from 6 centers obtained from 297 meningitis cases in the IMPACT database from 1991 through 1999. Vancomycin was used for empiric therapy in no cases and controls in 1991 to 1993 and in all cases in 1999. A third generation cephalosporin was used in 93.3% of confirmed PNSP cases, and 70.0% also received vancomycin and/or rifampin. Penicillin was used in 66.7% of confirmed PSSP cases. PNSP cases were more likely than PSSP controls to have a second lumbar puncture (odds ratio, 4.1; P= 0.01). PNSP cases were treated with intravenous antibiotics for an average of 15.6 days compared with 12.3 days for controls ( P= 0.04). Among PNSP cases, those patients who did not receive empiric vancomycin were treated with intravenous antibiotics for an average of 18.5 days compared with 12.0 days for those who did receive empiric vancomycin ( P= 0.04). The overall mortality was 5.3%, and 36.6% of survivors had >or=1 neurologic sequelae, including 19.7% with hearing loss. In multivariate statistical models, PNSP was not a risk factor for intensive care unit admission or neurologic sequelae.

CONCLUSIONS

Management of suspected bacterial meningitis and confirmed meningitis in Canadian children changed in the past decade. Treatment of PNSP meningitis is significantly different from that for PSSP meningitis. These changes have occurred in response to the emergence of PNSP in Canada. Neurologic sequelae remain common after meningitis, but there are no differences between PNSP cases and PSSP cases.

Effect of penicillin resistance of Streptococcus pneumoniae on the presentation, prognosis, and treatment of pneumococcal endocarditis in adults

We performed a clinical study of pneumococcal endocarditis (PE) in adults at 15 major Spanish hospitals during a 21-year period (1978-1998). During this time, 63 patients had PE due to Streptococcus pneumoniae diagnosed. Of the 63 isolates recovered from these patients, 24 (38%) and 6 (10%) showed resistance to penicillin (minimum inhibitory concentration [MIC], 0.1-4 microg/mL) and cefotaxime (MIC, 1 microg/mL), respectively. Twenty-two (35%) of the patients died. Left-side heart failure, but not penicillin resistance, was independently associated with a higher risk of death (odds ratio, 1.33; 95% confidence interval, 1.04-1.71; P=.026). Patients without meningitis who had PE due to penicillin-resistant S. pneumoniae could be treated with high-dose penicillin or a third-generation cephalosporin if the MIC for penicillin was < or =1 microg/mL. For patients with concurrent meningitis, high doses of cefotaxime could be used if the MIC for cefotaxime was < or =1 microg/mL. Early recognition of heart failure and surgery may help to decrease mortality.

Management of pneumococcal meningitis

During the past decade antibiotic resistance among Streptococcus pneumoniae isolates has complicated the empiric approach to and treatment of pneumococcal meningitis. Standard empiric therapy for suspected bacterial meningitis for infants and children older than 1 month of age is the combination of cefotaxime or ceftriaxone and vancomycin. Treatment is modified after antimicrobial susceptibilities are available. The optimal treatment of pneumococcal meningitis caused by strains with a cefotaxime/ceftriaxone MIC >2 microg/ml is unknown, although the addition of rifampin to the initial combination is generally recommended. The role of newer agents including quinolones is under investigation. Dexamethasone remains the only adjunctive antiinflammatory therapy to consider. The empiric approach to the child with suspected bacterial meningitis who has received the pneumococcal conjugate vaccine currently remains unchanged.

Pneumococcal meningitis in the intensive care unit: prognostic factors of clinical outcome in a series of 80 cases

We have undertaken this retrospective study to determine factors associated with in-hospital mortality and morbidity in 80 adult patients with severe Streptococcus pneumoniae meningitis. Clinical characteristics at admission of patients infected with susceptible (n = 54) and nonsusceptible (n = 17) strains to penicillin G were similar: age: 51 +/- 19 versus 58 +/- 15 yr (p = 0.16); Simplified Acute Severity Score (SAPS II): 39 +/- 14 versus 41 +/- 11 (p = 0.68); and Glasgow Coma Score: 8 +/- 3 versus 9.5 +/- 3 (p = 0.21), respectively. In-hospital mortality was 25% (20/80), with one death among the 17 patients (6%) infected with a nonsusceptible strain (p = 0.03). High-dose dexamethasone was used in 22 cases. By multivariate analysis, three factors were independently associated with death: platelet count < 100 G/L (adjusted odds ratio [aOR] = 32.7; 95% CI = 3.2 to 332.5; p = 0.0032), arterial pH > 7.47 (aOR = 33.1; 95% CI = 3.4 to 319.7; p = 0.0025), and mechanical ventilation (aOR = 48.8; 95% CI = 2.6 to 901.5; p = 0.009). When adjusting for the identified prognostic factors, corticosteroids significantly reduced the risk of death (aOR = 0.069; 95% CI = 0.005 to 0.9; p = 0.048). Only SAPS II was predictive of adverse outcome (death or neurologic deficit). We conclude that in intubated patients with S. pneumoniae meningitis, hyperventilation should be used with caution. Nonsusceptibility to penicillin G is not associated with a worse outcome. High-dose corticosteroids may be beneficial in the most severely ill patients.

Treatment of Bacterial Meningitis

The therapeutic approach to acute bacterial meningitis has changed in recent years as a result of changes in in vitro susceptibility of many meningeal pathogens to previously standard antimicrobial therapy. Given the emergence of strains of Streptococcus pneumoniae that are resistant to penicillin and the cephalosporins, the combination of vancomycin plus a third-generation cephalosporin is recommended as empiric therapy for suspected or proven pneumococcal meningitis, pending results of in vitro susceptibility testing. Strains of Neisseria meningitidis with reduced susceptibility to penicillin have also been described, although most patients with these resistant strains have recovered with standard penicillin therapy. Although the third-generation cephalosporins have greatly improved outcome in patients with meningitis caused by aerobic gram-negative bacilli, many organisms in this group are now resistant to these drugs; the carbapenems and fluoroquinolones may be effective alternative agents and have been successfully used in small case series. Further surveillance of the in vitro antimicrobial susceptibility patterns of meningeal pathogens is critical for future recommendations in the treatment of bacterial meningitis.

Quinolone treatment for pediatric bacterial meningitis: a comparative study of trovafloxacin and ceftriaxone with or without vancomycin

BACKGROUND

Trovafloxacin is a new fluoroquinolone that exhibits good penetration into the central nervous system and excellent antimicrobial activity against common meningeal pathogens, including beta-lactam-resistant pneumococci.

PURPOSE AND DESIGN

A multicenter, randomized clinical trial was conducted in children with bacterial meningitis to compare the safety and efficacy of trovafloxacin with that of ceftriaxone with or without vancomycin therapy.

RESULTS

A total of 311 patients, ages 3 months to 12 years, were enrolled, of whom 203 were fully evaluable, 108 treated with trovafloxacin and 95 with the conventional regimen. Both groups were comparable with regard to baseline characteristics: age; cerebrospinal fluid findings; use of dexamethasone; history of seizures; and etiologic agents. No significant differences between trovafloxacin and the comparator, respectively, were detected in any of the following outcome measures: clinical success at 5 to 7 weeks after treatment (79% vs. 81%); deaths (2% vs. 3%); seizures after enrollment (22% vs. 21%); and severe sequelae (14% vs. 14%). Only 4 of 284 children developed joint abnormalities up to 6 months after treatment, 1 (0.9%) child received trovafloxacin and 3 (3.1%) received the comparator regimen. None of the evaluable patients experienced significant abnormalities of liver function during treatment. One nonevaluable patient who received trovafloxacin for 5 days and ceftriaxone for 11 days was readmitted to the hospital with hepatitis of unknown etiology 1 day after discharge. The episode resolved with liver function tests returning to normal within 2 months.

CONCLUSIONS

We conclude that trovafloxacin is an effective antibiotic for treatment of pediatric bacterial meningitis. These favorable results support further evaluation of fluoroquinolone therapy for children with meningitis or other serious bacterial infections.

BMS-284756 in experimental cephalosporin-resistant pneumococcal meningitis

BMS-284756 is a novel des-fluoro(6) quinolone with a broad antimicrobial activity, including Streptococcus pneumoniae. The purpose of this study was to evaluate the pharmacodynamic profile and effectiveness of BMS-284756 for therapy of experimental meningitis caused by penicillin- and cephalosporin-resistant S. pneumoniae (CRSP). Meningitis was induced in rabbits by intracisternal inoculation of CRSP. BMS-284756 was given intravenously 16 h after intracisternal inoculation in single doses of 2.5 (n = 5 animals), 5 (n = 6), 10 (n = 6), 20 (n = 8), and 30 mg/kg (n = 6), in two doses of 10 mg/kg each separated by 5 h (n = 4), and as a 20-mg/kg dose followed 5 h later by 10 mg/kg (n = 5). The MICs and MBCs of BMS-284756, ceftriaxone, and vancomycin were 0.06 and 0.06, 4 and 4, and 0.25 and 0.25 microg/ml, respectively. After single doses of 10, 20, and 30 mg/kg, the maximum concentrations in cerebrospinal fluid (CSF) (mean +/- standard deviation) were 0.32 +/- 0.12, 0.81 +/- 0.38, and 1.08 +/- 0.43 microg/ml, respectively; the elimination half-life in CSF was 4.5 to 6.3 h. The CSF bacterial killing rates (BKR) at 5 h of the single-dose regimens of 10, 20 and 30 mg/kg were -0.84 +/- 0.48, -1.09 +/- 0.32, and -1.35 +/- 0.05 Deltalog(10) CFU/ml/h. The BKR(0-5) of the divided regimens (10 mg/kg twice and 20 mg/kg followed by 10 mg/kg) was -0.82 +/- 0.52 and -1.24 +/- 0.34 Deltalog(10) CFU/ml/h, respectively. The BKR(0-5) of the combined therapy with vancomycin and ceftriaxone was -1.09 +/- 0.39 Deltalog(10) CFU/ml/h. The penetration of BMS-284756 into purulent CSF relative to plasma was 14 to 25%. The bactericidal effect of BMS-284756 in CSF was concentration dependent. BMS-284756 at 30 mg/kg as a single or divided dose was as effective as standard therapy with vancomycin and ceftriaxone.

Clinical outcomes of bacteremic pneumococcal pneumonia in the era of antibiotic resistance

Limited data are available about the impact of antimicrobial resistance on clinical outcomes in cases of pneumococcal pneumonia. This was studied in 146 persons hospitalized with invasive pneumonia due to Streptococcus pneumoniae (minimum inhibitory concentration of cefotaxime, > or = .25 microg/mL) who were identified through population-based active surveillance for the period of November 1994 through April 1996. Compared with matched control subjects who had infection with more-susceptible S. pneumoniae, the proportion of subjects who died or who were admitted to an intensive care unit did not differ significantly. Multivariable analysis showed no significant contribution of antimicrobial resistance to mortality or the requirement for care in an intensive care unit. The ability to detect an effect of antimicrobial resistance on these important outcome measures may have been influenced by aggressive multidrug empirical therapy in this group of hospitalized patients. Factors other than resistance, such as severity of illness at presentation and advance directive status ("do not resuscitate" orders), appear to have a stronger influence on pneumococcal pneumonia outcomes.

Pneumococcal meningitis in children: relationship of antibiotic resistance to clinical characteristics and outcomes

BACKGROUND

The relationship of antibiotic susceptibility to clinical outcome in children with pneumococcal meningitis is uncertain. Previous studies have been limited by inclusion of relatively few patients infected with nonsusceptible pneumococci and inconsistent use of empiric vancomycin.

METHODS

Medical records of 86 children with culture-confirmed pneumococcal meningitis at a single institution from October, 1991, to October, 1999, were retrospectively reviewed, and differences in presentation and outcome based on antibiotic susceptibility of pneumococcal isolates were assessed.

RESULTS

Of 86 isolates 34 were nonsusceptible to penicillin (12 resistant). Of 60 isolates for which cefotaxime susceptibility data were available, 17 were nonsusceptible (12 resistant). Antibiotic susceptibility was not significantly associated with death, intensive care unit admission, mechanical ventilation, focal neurologic deficits, seizures, secondary fever, abnormal neuroimaging studies or hospital days. Children with penicillin-resistant isolates had significantly higher median blood leukocyte counts (24,100/microliter vs. 15,700/microliter, P = 0.03) and lower median CSF protein concentrations (85 mg/dl vs. 219 mg/dl, P = 0.04), were more likely to have a CSF glucose concentration of > or = 50 mg/dl (7 of 11 vs. 15 of 68, P = 0.009) and had lower rates of sensorineural hearing loss (1 of 8 vs. 25 of 40, P = 0.02) than children with isolates that were not resistant to penicillin. Children with cefotaxime-nonsusceptible isolates had an increased median duration of primary fever compared with those with nonsusceptible strains (6 days vs. 3.5 days, P = 0.02).

CONCLUSIONS

In children with pneumococcal meningitis, penicillin resistance was associated with a reduced risk of hearing loss, while cefotaxime resistance was associated with a longer duration of fever. Other outcome measures were not significantly influenced by the antibiotic susceptibility of pneumococcal isolates.

Pneumococcal disease in childhood

Streptococcus pneumoniae is the most common cause of serious bacterial infections in children worldwide. Problems with antibiotic resistance have lead to changes in antibiotic policies for children with possible pneumococcal disease. Demonstration of the efficacy of a pneumococcal conjugate vaccine has lead to consideration of its inclusion in routine infant vaccination schedules.

Increasing threat of Gram-positive bacterial infections in the intensive care unit setting

The effects of resistance are being noted on an increasing scale in the intensive care unit (ICU). Around the world, new epidemiologic patterns of ICU occurrence are being observed for Gram-positive multidrug-resistant organisms. Current problems include the appearance of insusceptibility to vancomycin and other glycopeptides in Staphylococcus aureus organisms that are virulent enough to cause infection in patients with normal host defenses. In addition, multidrug-resistant organisms like methicillin-resistant S.aureus are spreading from healthcare to community settings, and community organisms like Streptococcus pneumoniae are spreading to healthcare settings. Focal persistence and subsequent worldwide spread of enterococci resistant to vancomycin and other glycopeptides and multiple-resistance mechanisms in the same organism also require attention. Strategies such as multidisciplinary management of infections, appropriate infection control measures, and surveillance of resistance patterns are necessary to address the problem of resistance. Intensivists have been prominent in research and control efforts in this field and should continue to lead future efforts.