Dexamethasone therapy for bacterial meningitis. Results of two double-blind, placebo-controlled trials

Bacterial meningitis in children. Selected aspects

Accumulating clinical experience has gradually outlined the epidemiology of acute bacterial meningitis, including the epidemic and the sporadic forms, the customary clinical signs related to different age groups and causative organisms, and methods of rapid diagnosis by laboratory examinations. Effective treatment, which continues to evolve, emerged in the 1940s with the development of antibacterial antimicrobials, first with the sulfonamides and then with the penicillins. The literature relative to these aspects of the disease has been abundant in the past few years. This article is directed to a variety of topics that have direct bearing on the disorder but are less often addressed to those who deal with infants and children.

Local induction of tumor necrosis factor as a molecular mechanism of mucosal damage by gonococci

Tumor necrosis factor (TNF) is an endogenously produced cytokine that plays a critical role in mediating septic shock and multi-organ failure, but previous studies of the role TNF in disease have not examined its role in mucosal disease processes. In an experimental model of acute gonococcal salpingitis, gonococcal infection of human fallopian tube mucosa resulted in increased mucosal production of TNF. Recombinant human TNF-alpha damaged fallopian tube mucosa in a dose-response manner and produced epithelial damage with the same ultrastructural features as those observed in gonococcal infection. Blocking production of TNF during gonococcal infection diminished the extent of damage to fallopian tube mucosa. In addition to mediating systemic disease, such as septic shock, TNF is also produced locally, and can play a critical role in mediating mucosal disease processes, such as acute gonococcal salpingitis.

Treatment options for the pharmacological therapy of neonatal meningitis

Neonatal bacterial meningitis has a relatively low incidence in developed countries, but continues to cause morbidity and mortality despite advances in antimicrobial therapy. Bacterial pathogens commonly associated with neonatal meningitis include Group B streptococci, Escherichia coli K1 and other coliforms, Listeria monocytogenes and staphylococci. As it can be difficult to differentiate meningitis from septicaemia in neonates, empirical antibiotic therapy should be effective for both. Selection of an empirical antibiotic regimen should be based on: (a) bacterial prevalence and susceptibility; (b) drug characteristics; (c) postnatal age at the onset of disease; and (d) patient-specific factors. A penicillin in combination with an aminoglycoside or cefotaxime is commonly used in empirical therapies. The increased risk of staphylococcal infection in older neonates requires consideration of an antistaphylococcal antibiotic in the empirical therapy regimen. Once a causative organism has been identified, antimicrobial therapy should be directed towards that pathogen. Duration of therapy remains empirical, but should be at least 7 days for documented bacterial meningitis. Viral meningitis continues to have a high mortality despite the availability of antiviral agents. Adjunctive therapies may further reduce the morbidity and mortality of meningitis. While most of these therapeutic options have not been investigated in neonates, they may prove to be of benefit in the future. Anti-inflammatory agents, such as glucocorticoids, nonsteroidal anti-inflammatory agents and immunoglobulin, may modulate the inflammatory response of a meningeal infection. Other possible therapies in neonatal meningitis include cerebral blood flow modulators and disease prevention with maternal vaccines and perinatal antibiotics. Practical aspects of drug therapy such as route of administration and serum drug concentration monitoring can improve both drug therapy and patient outcome. While antibiotics have greatly improved the treatment outcome of neonatal meningitis, it is clear that additional intervention will be required to increase cure rates and reduce sequelae.

Cytokines, receptors, and inhibitors

Cytokines are endogenous mediators in inflammatory and immunologic host defense reactions. In various diseases cytokines produced in excess cause systemic or local toxic effects. Cytokines therefore are tightly controlled by regulation of their biosynthesis and release and by counteracting mechanisms which limit their activities. Two new cytokine inhibitory mechanisms have recently been discovered. First, the generation of soluble receptors which compete with cellular receptors for cytokine binding has been recognized as a general phenomenon. Second, a receptor antagonist polypeptide binding to the receptor but not eliciting biological activity has been discovered in the IL-1 system. These polypeptides, when expressed in various recombinant forms, are not only research tools but may find also direct clinical use.

Effect of dexamethasone or HWA-138 in combination with antibiotics in experimental Haemophilus influenzae type b infection

Modulation of the host's inflammatory response in bacterial meningitis may be beneficial. In this study, the effects of dexamethasone and HWA-138, an analog of pentoxifylline, on CSF cultures and cochlear inflammation in an infant rat model of Haemophilus influenzae type b were studied. Five-day-old infant rats were inoculated once intraperitoneally with 1 x 10(4) to 10 x 10(4) CFU of H. influenzae type b (strain 1406). Twenty-four hours later, infant rats were treated intraperitoneally with one dose of ampicillin (0.1 mg/g of body weight), cefotaxime (0.05 mg/g), or cefuroxime (0.05 mg/g) alone or in combination with one dose of dexamethasone (0.00015 mg/g) or HWA-138 (0.005 mg/g). Twenty-four hours after treatment with cefuroxime plus dexamethasone, animals had a significantly (P less than or equal to 0.04) greater incidence of bacteremia and meningitis (eight of nine animals) than that in animals of the other treatment groups. Overall, dexamethasone was associated with less inflammation (P less than 0.04) of the cochlear nerve compared with that from antibiotic treatment alone. In this model, when suboptimal antimicrobial therapy is administered, anti-inflammatory agents may be beneficial with respect to reducing cochlear inflammation. However, dexamethasone and cefuroxime lead to a higher rate of positive blood and cerebral spinal fluid cultures than cefuroxime alone.

Use of ampicillin-sulbactam for treatment of experimental meningitis caused by a beta-lactamase-producing strain of Escherichia coli K-1

We evaluated the pharmacokinetics and therapeutic efficacy of ampicillin combined with sulbactam in a rabbit model of meningitis due to a beta-lactamase-producing strain of Escherichia coli K-1. Ceftriaxone was used as a comparison drug. The MIC and MBC were 32 and greater than 64 micrograms/ml (ampicillin), greater than 256 and greater than 256 micrograms/ml (sulbactam), 2.0 and 4.0 micrograms/ml (ampicillin-sulbactam [2:1 ratio, ampicillin concentration]) and 0.125 and 0.25 micrograms/ml (ceftriaxone). All antibiotics were given by intravenous bolus injection in a number of dosing regimens. Ampicillin and sulbactam achieved high concentrations in cerebrospinal fluid (CSF) with higher dose regimens, but only moderate bactericidal activity compared with that of ceftriaxone was obtained. CSF bacterial titers were reduced by 0.6 +/- 0.3 log10 CFU/ml/h with the highest ampicillin-sulbactam dose used (500 and 500 mg/kg of body weight, two doses). This was similar to the bactericidal activity achieved by low-dose ceftriaxone (10 mg/kg), while a higher ceftriaxone dose (100 mg/kg) produced a significant increase in bactericidal activity (1.1 +/- 0.4 log10 CFU/ml/h). It appears that ampicillin-sulbactam, despite favorable CSF pharmacokinetics in animals with meningitis, may be of limited value in the treatment of difficult-to-treat beta-lactamase-producing bacteria, against which the combination shows only moderate in vitro activity.

Acute Therapy of Bacterial Meningitis

Antimicrobial therapy for bacterial meningitis has markedly reduced mortality rates from this disorder. The efficacy of an antibiotic in meningitis depends on many factors, including its penetration into cerebrospinal fluid (CSF), the bactericidal efficacy of the antibiotic within purulent CSF, and the need for bactericidal activity in CSF because bacterial meningitis represents an infection in an area of impaired host defense. Penicillin G and ampicillin are equally efficacious for meningitis caused by Streptococcus pneumoniae or Neisseria meningitidis. This recommendation may change, however, with the emergence of strains of pneumococci or meningococci that are relatively or highly resistant to penicillin; a third-generation cephalosporin (cefotaxime or ceftriaxone) should be used for meningitis due to relatively resistant strains and vancomycin for pneumococcal meningitis caused by strains that are highly resistant to penicillin. With the high percentage of strains of Haemopbilus influenzae type b that produce β-lactamase, empiric therapy when this organism is suspected should consist of a third-generation cephalosporin; these agents are also used for meningitis caused by enteric gram-negative bacilli, and one agent, ceftazidime, is effective against Pseudomonas aeruginosa meningitis. Despite the availability of effective bactericidal antibiotics, morbidity and mortality from bacterial meningitis remains unacceptably high. Recent studies using animal models of infection have demonstrated the beneficial effect of antiinflammatory agents in attenuating the CSF inflammatory response that may lessen many of the pathophysiological consequences of meningitis. Studies of adjunctive dexamethasone therapy suggest that these agents may reduce morbidity (specifically sensorineural hearing loss) and mortality (due to S. pneumoniae) in patients with bacterial meningitis. Controversy remains, however, concerning the use of dexamethasone in all patients with bacterial meningitis and further studies are necessary. In critically ill patients with bacterial meningitis, control of increased intracranial pressure and seizures may be useful and necessary in improving outcome.

The beneficial effects of early dexamethasone administration in infants and children with bacterial meningitis

BACKGROUND

In experimental models of meningitis and in children with meningitis, dexamethasone has been shown to reduce meningeal inflammation and to improve the outcome of disease.

METHODS

We conducted a placebo-controlled, double-blind trial of dexamethasone therapy in 101 infants and children admitted to the National Children's Hospital, San José, Costa Rica, who had culture-proved bacterial meningitis or clinical signs of meningitis and findings characteristic of bacterial infection on examination of the cerebrospinal fluid. The patients were randomly assigned to receive either dexamethasone and cefotaxime (n = 52) or cefotaxime plus placebo (n = 49). Dexamethasone (0.15 mg per kilogram of body weight) was given 15 to 20 minutes before the first dose of cefotaxime and was continued every 6 hours thereafter for four days.

RESULTS

The demographic, clinical, and laboratory profiles were similar for the patients in the two treatment groups. By 12 hours after the beginning of therapy, the mean opening cerebrospinal pressure and the estimated cerebral perfusion pressure had improved significantly in the dexamethasone-treated children but worsened in the children treated only with cefotaxime (controls). At 12 hours meningeal inflammation and the concentrations of two cytokines (tumor necrosis factor alpha and platelet-activating factor) in the cerebrospinal fluid had decreased in the dexamethasone-treated children, whereas in the controls the inflammatory response in the cerebrospinal fluid had increased. At 24 hours the clinical condition and mean prognostic score were significantly better among those treated with dexamethasone than among the controls. At follow-up examination after a mean of 15 months, 7 of the surviving 51 dexamethasone-treated children (14 percent) and 18 of 48 surviving controls (38 percent) had one or more neurologic or audiologic sequelae (P = 0.007); the relative risk of sequelae for a child receiving placebo as compared with a child receiving dexamethasone was 3.8 (95 percent confidence interval, 1.3 to 11.5).

CONCLUSIONS

The results of this study, in which dexamethasone administration began before the initiation of cefotaxime therapy, provide additional evidence of a beneficial effect of dexamethasone therapy in infants and children with bacterial meningitis.

The role of corticosteroids in infants and children with bacterial meningitis

Bacterial meningitis continues to be a cause of substantial morbidity in infants and children. Hearing impairment is the most common sequela of this disease. Corticosteroids have been used in an attempt to reduce the incidence of meningitis-induced hearing loss. Some studies have demonstrated a decrease in the incidence of hearing impairment in patients treated with cefuroxime plus dexamethasone compared with cefuroxime alone. Similar data are lacking for other frequently used antibiotics. Based on these studies, the use of dexamethasone should be considered in infants and children greater than two months of age with suspected bacterial meningitis. Critical issues including the timing of steroid initiation in relation to antibiotic therapy and the appropriate antibiotic-corticosteroid regimen must be addressed. Studies should be performed to define the exact role of corticosteroids in the treatment of bacterial meningitis. Until additional data are available, we recommend the use of dexamethasone in pediatric patients older than two months of age with bacterial meningitis.

Temperature-dependent modulation of lipopolysaccharide-induced interleukin-1 beta and tumor necrosis factor alpha expression in cultured human astroglial cells by dexamethasone and indomethacin

In bacterial meningitis, LPS induces production in cerebrospinal fluid of the cytokines IL-1 beta and tumor necrosis factor alpha (TNF alpha), which are the principle mediators of meningeal inflammation. IL-1 beta and TNF alpha induce fever, and elevated temperature may affect cytokine expression. Dexamethasone treatment improves outcome in bacterial meningitis possibly by inhibiting IL-1 beta and TNF alpha. In this report, the effects of elevated temperature and dexamethasone on LPS-stimulated IL-1 beta and TNF alpha mRNA gene expression and protein synthesis were studied in human astrocytoma cell lines and primary cultures of human fetal astrocytes. Cells cultured at 40 degrees C exhibited smaller peaks of IL-1 beta and TNF alpha transcription and protein synthesis compared with cells cultured at 37 degrees C. The addition of dexamethasone before, during, or after exposure of the cells to LPS resulted in temperature-dependent inhibition of IL-1 beta transcription and protein synthesis. The most extensive inhibition occurred in pretreated cells cultured at 37 degrees C. Cotreatment with LPS and dexamethasone also inhibited TNF alpha mRNA transcription at both temperatures. The effects of another antiinflammatory agent, indomethacin, on LPS induction of IL-1 beta and TNF alpha mRNA were temperature and cell line dependent. These findings provide a possible explanation for the efficacy of dexamethasone treatment of bacterial meningitis and support the proposal that fever may be beneficial to the host in this disease.

Infantile meningitis in England and Wales: a two year study

A two year prospective study identified 1922 cases of meningitis in children under 1 year of age. A further 201 cases were identified from other sources. The annual incidence of meningitis during the first year of life was 1.6/1000; during the first 28 days of life it was 0.32/1000, and among postneonatal infants it was 1.22/1000. The male:female ratio was 1.4:1. The overall case fatality rate was 19.8% for neonates and 5.4% for postneonatal infants. Two thirds of deaths identified in the study, 50% of all deaths, were not attributed to meningitis by the Office of Population Censuses and Surveys. Group B beta haemolytic streptococci (28%), Escherichia coli (18%), and Listeria monocytogenes (5%) were most frequently isolated from neonates and Neisseria meningitidis (31%), Haemophilus influenzae (30%), and Streptococcus pneumoniae (10%) from postneonatal infants. At 2-6 months of age N meningitidis meningitis was most common, and at 7-12 months H influenzae predominated. Meningitis caused by group B beta haemolytic streptococci occurred up to 6 months of age and had a consistent mortality of 25%. Neonatal meningitis due to Gram negative enteric rods had a mortality of 32%. Low birth weight was a significant predisposing factor for both neonates and postneonatal infants. In both groups mortality was significantly higher among children admitted in coma. There was no seasonal variation in incidence in either group. Neonates were treated with either group. Neonates were treated with either chloramphenicol (50%) or gentamicin (48%) usually in combination with a penicillin; 40% received a third generation cephalosporin. Of the 1472 postneonatal infants treated 84% received chloramphenicol with a penicillin and 10% received a third generation cephalosporin. Relapse occurred in 49 patients and three died. Eighteen babies coned as a result of raised intracranial pressure, including four neonates, and four died. Mortality among the 133 (7%) children who received steroids was significantly higher than in the rest of the study group.

Pharmacokinetics and antibacterial efficacy of cefpirome (HR 810) in experimental Escherichia coli and Haemophilus influenzae type b meningitis

Cefpirome (HR 810) is a new cephalosporin related to cefotaxime that has potent bactericidal activity against a broad spectrum of gram-negative and gram-positive organisms. The pharmacokinetics and bacteriological efficacy of cefpirome administered as a single intravenous dose were assessed in rabbits with experimental Haemophilus influenzae type b and Escherichia coli K1 meningitis. The mean penetrations into the cerebrospinal fluid (CSF) in relation to the amount of drug in serum of animals infected with H. influenzae and E. coli were 25 and 54%, respectively. The median CSF bactericidal titers were 1:128 against both organisms at 1 h of uninfected animals, the mean penetration was 4.5%. There was a significant reduction in the concentrations of bacteria in CSFs of both groups of animals treated with cefpirome compared with that in untreated groups. Mortality was also significantly lower in treated animals than it was in untreated animals. Intravenous administration of dexamethasone before the cefpirome dose did not compromise penetration, bactericidal titers, or antibacterial activity of cefpirome in CSF.

Endotoxin induced damage to the cochlea in guinea pigs

An apparently unique form of cochlear damage was produced in guinea pigs by perfusing the cochlea or injecting the cerebrospinal fluid with bacterial endotoxin. This developed rapidly (within two hours) and was characterised by swelling of the tectorial membrane and damage to both inner and outer hair cells, with parallel functional damage demonstrable electrophysiologically. All these changes could be attenuated by pretreatment with dexamethasone. Such endotoxin mediated lesions may be the mechanism by which hearing loss occurs in bacterial meningitis.

Mediators of meningitis: therapeutic implications

Despite the availability of potent antibiotics, bacterial meningitis is still a major clinical problem. Mortality is high, and up to a third of survivors are left with neurologic sequelae that may range from mild behavioral disorders to mental retardation or deafness. New therapeutic approaches to meningeal inflammation, however, are reducing the neurologic risks.

Antibiotic treatment of community acquired bacterial meningitis

Community acquired meningitis is predominantly caused by three agents: Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis Four physical properties of available drugs--molecular size, protein binding, lipid solubility and ionization--affect drug entry to the central nervous system (CNS). These factors, coupled with acute changes in blood-brain barriers and intrinsic bactericidal activity, have a bearing on the success of treatment with all agents. Third generation cephalosporins have largely supplanted older regimens due to their intrinsic qualities of greater bactericidal activity, optimal cerebrospinal fluid pharmacokinetics, and low toxicity. The pharmacological principles of treatment of CNS bacterial infections, pharmacology of available drugs, and current treatment recommendations are reviewed.

Acute phase reactants and risk of bacterial meningitis among febrile infants and children

STUDY OBJECTIVE

To test the hypothesis that quantitation of either C-reactive protein (CRP) or the total peripheral WBC count can improve clinical detection of underlying bacterial meningitis among young febrile children.

DESIGN

Cross-sectional survey of selected symptoms of central nervous system infection, signs of meningeal irritation and/or elevated intracranial pressure, levels of CRP in serum, and total peripheral WBC counts among unselected pediatric patients undergoing lumbar punctures for evaluation of acute febrile illnesses.

SETTING

Emergency department and acute care "walk-in" clinic of an urban, university-affiliated general hospital.

PARTICIPANTS

160 previously well, acutely febrile infants and children (median age, 6 months).

RESULTS

The prevalence of bacterial meningitis was 6%. Sensitivity of symptoms was 1.00 and specificity was 0.17. Sensitivity of signs was 0.70 and specificity was 0.81. Of the acute phase reactants, sensitivity of a CRP level of more than 1.0 mg/dL was 0.80, while that of a total peripheral WBC count of more than 15,000/mm3 was 0.40. The presence of signs and/or a CRP level of more than 1.0 mg/dL correctly identified all children with bacterial meningitis (sensitivity, 1.00). The absence of signs and a CRP level of 1.0 mg/dL or less correctly identified 71 of 150 children without bacterial meningitis (specificity, 0.47). Of 125 children without meningeal signs, the combination of symptoms and a CRP level of more than 1.0 mg/dL correctly identified all three children with bacterial meningitis (sensitivity, 1.00). The absence of these symptoms and/or a CRP level of 1.0 mg/dL or less correctly identified 80 of 122 children without bacterial meningitis (specificity, 0.66).

CONCLUSION

Quantitation of CRP but not the total peripheral WBC count can increase the sensitivity of physical examination findings and the specificity of symptoms for the diagnosis of bacterial meningitis. Measurement of CRP in serum is useful as an adjunct to history and physical examination for the detection of acute bacterial meningitis in the acutely febrile child.

Cytokines in the pathogenesis of bacterial meningitis

Adjunctive dexamethasone therapy to antibiotic therapy for bacterial meningitis has been shown in several studies to be beneficial. The roles of interleukin 1 beta and tumour necrosis factor alpha (TNF-alpha) in bacterial meningitis and in an experimental rabbit model are reviewed; both cytokines play a pivotal role in induction of meningitis. Using dexamethasone with the initial dose of antibiotics caused a decrease in TNF-alpha and modulated the inflammatory response. Early use of adjunctive dexamethasone is important in therapy of bacterial meningitis.

Seizures and other neurologic sequelae of bacterial meningitis in children

BACKGROUND

Although the mortality rate among children with bacterial meningitis has decreased dramatically in recent decades, some patients are left with neurologic sequelae. It has not been clearly established which features of the acute illness predict the chronic neurologic sequelae, including late seizures or epilepsy.

METHODS

We followed 185 infants and children prospectively during and after acute bacterial meningitis. The mean duration of follow-up was 8.9 years (range, 0.1 to 15.5). During the first six years standard neurologic examinations were performed; telephone interviews were conducted thereafter.

RESULTS

One month after meningitis, 69 children (37 percent) had neurologic abnormalities. Many of these signs resolved within a year, leaving only 26 children (14 percent) with persistent deficits: 18 (10 percent) had only sensorineural hearing loss, and 8 (4 percent) had multiple neurologic deficits. Thirteen children (7 percent) had one or more late seizures not associated with fever. The presence of persistent neurologic deficits indicative of cerebral injury was the only independent predictor of late afebrile seizures (P less than 0.001).

CONCLUSIONS

After bacterial meningitis only children with permanent neurologic deficits are at high risk for epilepsy. Those with normal examinations after the acute illness have an excellent change of escaping serious neurologic sequelae, including epilepsy.

The sequelae of Haemophilus influenzae meningitis in school-age children

BACKGROUND

Previous data on the consequences of Haemophilus influenzae type b meningitis for school-age children have been inconsistent, and much of the information on risk factors has been inconclusive. The present study was designed to evaluate the sequelae of this disease with a protocol for the comprehensive assessment of neuropsychological function.

METHODS

Ninety-seven school-age children (mean age, 9.6 years), each of whom had a school-age sibling, were recruited from a survey of the medical records of 519 children treated for H. influenzae type b meningitis between 1972 and 1984 (at a mean age of 17 months) at the children's hospitals of Toronto, Ottawa, and Montreal. Of the 97 children, 41 had had an acute neurologic complication. Sequelae were assessed by comparing the index children with their nearest siblings on the basis of standardized measures of cognitive, academic, and behavioral status.

RESULTS

Only 14 children (14 percent) had persisting neurologic sequelae: sensorineural hearing loss in 11 (unilateral in 6 and bilateral in 5), seizure disorder in 2, and hemiplegia and mental retardation in 1. Although the total sample of index children scored slightly below the siblings in reading ability, the 56 children without acute-phase neurologic complications (58 percent) were indistinguishable from their siblings on all measures. The differences between the groups were small even for the 41 pairs in which the index child had had an acute neurologic complication (mean full-scale IQ, 102 for the index children vs. 109 for the siblings). Sequelae were also associated with lower socioeconomic status and a lower ratio of glucose in cerebrospinal fluid to that in blood at the time of the meningitis. Behavioral problems were more prominent in index boys than index girls and in those who were older at the time of testing, but sex and age were not related to cognitive or academic sequelae.

CONCLUSIONS

We find a favorable prognosis for the majority of children who are treated for meningitis caused by H. influenzae type b.

Effects of cyclophosphamide on the pathogenesis of cytomegalovirus-induced labyrinthitis

Cyclophosphamide was used in this study to define the contribution of the inflammatory response relative to direct cytopathic effects of guinea pig cytomegalovirus (GPCMV) in inducing sensorineural hearing loss in the guinea pig. The eighth nerve compound action potential (CAP) threshold on day 7 after inoculation of GPCMV into the scala tympani was an average of 35 dB greater for control animals than for those that were immunosuppressed with daily intraperitoneal injections of cyclophosphamide (20 mg/kg body weight). The amount of GPCMV antigen in the cochlea, detected immunohistochemically did not correlate with the CAP threshold. However, the greater the inflammatory response to GPCMV in the cochlea, the higher the CAP threshold and thus the greater the hearing loss. This study demonstrates that the inflammatory response to GPCMV may be more important than direct cytopathic effects of the virus in producing sensorineural hearing loss in GPCMV-induced labyrinthitis.

Proteinase-antiproteinase imbalance in meningitis: determination of alpha 1 proteinase inhibitor (alpha 1PI), elastase-alpha 1PI complex, and elastase inhibition capacity in cerebrospinal fluid

Mortality and long-term neurologic sequelae are still frequent complications of meningitis despite effective antibiotic treatment. This suggests that pathogen-independent inflammatory mechanisms may play an important role in the course of this illness. Neutrophil granulocytes form the primary immune defense in meningitis. Once activated, these cells release elastase into the cerebrospinal fluid (CSF). Elastase may induce tissue damage if local antiproteinase capacity is low as under normal conditions. To define the relevance of this mechanism we studied 22 patients with meningitis. Concentrations of elastase in complex with the main antiproteinase alpha 1-proteinase inhibitor (elastase-alpha 1 PI), alpha 1-proteinase inhibitor (alpha 1PI), and elastase inhibition capacity (EIC) were measured in CSF of 9 patients with bacterial meningitis (BM), aged 1 month-14 years; 13 patients with non-bacterial meningitis (NBM), aged 1 month-15 years; and 20 patients in whom meningitis was excluded after spinal tap (control group), aged 6 months-15 years. The concentration of elastase-alpha 1PI in the BM group (median 552 micrograms/l) was significantly higher than in either the NBM group (median 30 micrograms/l, p less than 0.01) or the control group (median 30 micrograms/l, p less than 0.01). Similarly, the alpha 1PI-concentration in the BM group was significantly higher (median 113 mg/l) than either the NBM group (median 13.7 mg/l, p less than 0.025) or the control group (median 6.3 mg/l, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Labyrinthine ossification after meningitis: its implications for cochlear implantation

Labyrinthine ossification can be found in a high percentage of patients with profound deafness resulting from bacterial meningitis. Radiographic evidence of ossification can be found as early as 2 months after the acute infection, indicating that the intracochlear process probably begins much earlier. If long, intracochlear cochlear implants are to be most successfully used in these patients, an aggressive approach to clinical management following the meningitis should be taken. Illustrative case reports and suggested guidelines for evaluation and treatment are given.

Mechanisms of tumor-associated edema: a review

An understanding of the mechanisms responsible for tumor-associated edema involves the elucidation of the role played by a number of intra-related processes. These include (i) the permeability of new tumor microvessels that are associated with tumor angiogenesis; (ii) alterations in microvascular permeability due to factors secreted by tumor cells; (iii) immunological mechanisms and (iv) increased microvessel permeability associated with inflammation. The rationale for a role for inflammatory processes in tumor-associated edema has been outlined and the role of non-steroidal anti-inflammatory drugs in modulating experimental and human tumor-associated edema has been explored.

A comparison of ceftriaxone and cefuroxime for the treatment of bacterial meningitis in children

To compare ceftriaxone with cefuroxime for the treatment of meningitis, we conducted a study in which 106 children with acute bacterial meningitis were randomly assigned to receive either ceftriaxone (100 mg per kilogram of body weight per day, administered intravenously once daily; n = 53) or cefuroxime (240 mg per kilogram per day, administered intravenously in four equal doses; n = 53). The mean age of the children was 3 years (range, 42 days to 16 years), and the characteristics of the two treatment groups were comparable at admission. Excluded from the study were eight other children who died within 48 hours of admission. After 18 to 36 hours of therapy, cultures of cerebrospinal fluid remained positive for 1 of the 52 children (2 percent) receiving ceftriaxone for whom cultures were available and 6 of 52 (12 percent) receiving cefuroxime (P = 0.11). In both groups the mean duration of antibiotic therapy was 10 days. The clinical responses to therapy were similar in the two treatment groups, and all 106 children were cured. Reversible biliary pseudolithiasis was detected by serial abdominal ultrasonography only in the children treated with ceftriaxone (16 of 35 vs. 0 of 35; P less than 0.001). The treatment of three children was switched from ceftriaxone to alternative antibiotics because these children had upper abdominal pain. Other side effects were infrequent in both groups. At follow-up examination two months later, moderate-to-profound hearing loss was present in two children (4 percent) treated with ceftriaxone and in nine (17 percent) treated with cefuroxime (P = 0.05); other neurologic abnormalities were similar in the two treatment groups. We conclude that ceftriaxone is superior to cefuroxime for the treatment of acute bacterial meningitis in children and that the benefits of milder hearing impairment and more rapid sterilization of the cerebrospinal fluid with ceftriaxone outweigh the problem of reversible biliary pseudolithiasis with this drug.

Endemic bacterial meningitis in Sudanese children: aetiology, clinical findings, treatment and short-term outcome

During the period April 1985 to November 1986 (18 months), 196 children (of age greater than 1 month) admitted to the Children's Emergency Hospital in Khartoum, Sudan, with clinical suspicion of meningitis/meningoencephalitis were followed up prospectively. Bacterial meningitis was diagnosed by culture, direct microscopy and/or antigen-detecting assays (co-agglutination and enzyme immunoassay) in 44 infants (25 Haemophilus influenzae type b, 8 Neisseria meningitidis, 7 Streptococcus pneumoniae, 3 enterobacteria and one mixed infection), aseptic meningitis in 52, cerebral malaria in 4 and febrile convulsions in 96. The majority of cases of bacterial meningitis were boys and 57% of those in whom H. influenzae was the commonest isolate were less than 1 year old. The presenting signs and symptoms are described as well as the transient and permanent short-term sequelae. The total mortality from bacterial meningitis was 19%, permanent neurological sequelae were seen in 26% of survivors. Prospective follow-up, including audiometry, of 35 children 1-2 months after discharge showed that 11% had hemiplegia and 20% had hearing impairment. The potential impact of vaccination against invasive H. influenzae infections is discussed.