Bacterial meningitis in infants: neurological aspects

Clinical, neurologic and laboratory aspects of bacterial meningitis in the newborn infant are critically reviewed taking into account author's experience. Pathophysiologic data on acute phase phenomena in the CNS are analysed for this purpose.     

Adjunctive dexamethasone treatment in acute bacterial meningitis

The initiation of antibiotic treatment on suspicion of bacterial meningitis is important, but it is not enough to improve the prognosis for patients, especially those with pneumococcal meningitis. The mortality and morbidity of pneumococcal meningitis are still devastating, and results of a recent randomised trial have shown evidence in favour of dexamethasone treatment given before or with the first antibiotic dose. Adjuvant dexamethasone is unequivocally recommended in children and adults with haemophilus meningitis or pneumococcal meningitis. The benefit of adjunctive dexamethasone is likely to be greatest in patients who are otherwise healthy and present early with acute bacterial meningitis. Dexamethasone is not currently recommended for the treatment of gram-negative bacillary meningitis and neonatal meningitis. Dexamethasone, before or with the first dose of antibiotic, is likely to be one of the most significant practice changes that will benefit many adults and children with common types of acute bacterial meningitis and has been of proven value in the developed world.     

儿童难治性细菌性脑膜炎临床分析

目的 回顾性分析儿童难治性细菌性脑膜炎患儿的临床数据,以期提高儿童细菌性脑膜炎的诊治经验.方法 回顾性分析31例儿童难治性细菌性脑膜炎及病程>1个月的住院患儿的临床资料.结果 在抗生素治疗的基础上,大部分病例联合应用免疫治疗,发病后1 a成功随访23例,预后不良率高(69.57％);患儿住院期间血淋巴细胞亚群以CD19...     

Cerebrovascular involvement in the acute phase of bacterial meningitis

Cerebral ischaemia is a common complication of bacterial meningitis. Although cerebrovascular involvement in the acute phase of inflammation may be particularly important for the still unacceptably high morbidity and mortality, only, a few studies have investigated cerebrovascular changes in bacterial meningitis. We prospectively investigated changes of intracranial cerebral blood flow velocities (CBFV) in 22 patients (12 men, 10 women, mean age 48 years, 19 years, SD) with bacterial meningitis, by means of transcranial Doppler sonography (TCD). According to previously published criteria the degree of arterial narrowing was assessed and related to the patients’ outcome. Elevated CBFVs in the middle cerebral artery were documented in 18/22 patients with markedly increased systolic peak velocities (CBFV of > 210 cm/s) in 7 patients. Serial examinations performed in 11 patients showed elevated CBFV as early as day 1, reaching peak CBFV between day 3 and day 6 after onset of symptoms in most cases. Furthermore, cerebrovascular involvement was also documented by disturbances of physiological slow spontaneous oscillations of blood flow velocities in 5/10 patients examined with TCD. Low Glasgow Coma Scales (< 7) on admission (29% vs 0%), focal cerebral ischaemic deficits (29% vs 7%) and, seizures (43% vs 7%) were more frequent in patients with CBFV of > 210 cm/s. Finally, a poor clinical outcome was significantly related to severe vascular involvement (P < 0.05). Received: 26 February 1996 Received in revised form: 16 July 1996 Accepted: 5 August 1996     

Validation of diagnostic algorithm to differentiate between tuberculous meningitis and acute bacterial meningitis

Background

Discrimination between tuberculous and acute bacterial meningitis is difficult by clinical features alone and laboratory methods may only supplement the clinical suspicion. We aimed to validate the diagnostic criteria by Thwaites et al. [1] and construct our own diagnostic predictors based on the clinical and laboratory features.

Methods

380 patients of acute bacterial meningitis (ABM) and 210 patients of tuberculous meningitis (TBM) were enrolled retrospectively from June 2004 to June 2007 and prospectively from July 2007 to September 2008. HIV positive patients were excluded. Detailed history, clinical examination CSF analysis, haematological, biochemical investigations and imaging was performed in all patients.

Results

Factors associated with the diagnosis of TBM in the present study included rural area of residence, longer duration of disease, presence of clear CSF, lower percentage of CSF neutrophils, presence of diplopia and hemiparesis. On validation, age did not appear as a significant factor in our population. The diagnostic algorithm from our study group had a sensitivity of 95.71% and specificity of 97.63%.

Conclusions

The diagnostic criterion has a fair validation in our population when the age factor is excluded. The rule is useful in HIV negative patients with low CSF sugar and negative organism yield in the CSF.     

Brain phosphorus magnetic resonance spectroscopy in acute bacterial meningitis

The metabolic basis of the encephalopathy associated with acute bacterial meningitis is unknown. The presence of cerebrospinal fluid lactic acidosis and hypoglycorrhachia suggests that intracellular acidosis or cellular energy depletion may play a role. Phosphorus magnetic resonance spectroscopy allows for the noninvasive determination of intracellular pH and relative amounts of phosphate-containing metabolites in humans. In seven normal volunteers, the intracellular pH of a mixed volume of gray and white matter was 7.00 +/- 0.04 (mean +/- SD). The apparent relative intensities of resonances from adenosine triphosphate, phosphocreatine, phosphodiesters and phosphomonoesters, and inorganic phosphate were measured. An encephalopathic patient with pneumococcal meningitis who had severe cerebrospinal fluid lactic acidosis was studied. Brain intracellular pH and relative phosphate metabolite concentrations were normal. Intracellular acidosis and bioenergetic compromise are therefore not causes of encephalopathy in this disease. This also demonstrates that the human brain can maintain tight control of intracellular pH even in the presence of marked extracellular metabolic acidosis.     

The diagnosis and management of acute bacterial meningitis in resource-poor settings

Acute bacterial meningitis is more common in resource-poor than resource-rich settings. Survival is dependent on rapid diagnosis and early treatment, both of which are difficult to achieve when laboratory support and antibiotics are scarce. Diagnostic algorithms that use basic clinic and laboratory features to distinguish bacterial meningitis from other diseases can be useful. Analysis of the CSF is essential, and simple techniques can enhance the yield of diagnostic microbiology. Penicillin-resistant and chloramphenicol-resistant bacteria are a considerable threat in resource-poor settings that go undetected if CSF and blood can not be cultured. Generic formulations of ceftriaxone are becoming more affordable and available, and are effective against meningitis caused by penicillin-resistant or chloramphenicol-resistant bacteria. However, infection with Streptococcus pneumoniae with reduced susceptibility to ceftriaxone is reported increasingly, and alternatives are either too expensive (eg, vancomycin) or can not be widely recommended (eg, rifampicin, which is the key drug to treat tuberculosis) in resource-poor settings. Additionally, improved access to affordable antibiotics will not overcome the problems of poor access to hospitals and the fatal consequences of delayed treatment. The future rests with the provision of effective conjugate vaccines against S pneumoniae, Haemophilus influenzae, and Neisseria meningitides to children in the poorest regions of the world.     

Utility of cerebrospinal fluid cortisol level in acute bacterial meningitis

Background:

Meningitis remains a serious clinical problem in developing as well as developed countries. Delay in diagnosis and treatment results in significant morbidity and mortality. The role and levels of intrathecal endogenous cortisol is not known.

Objective:

To study the cerebrospinal fluid (CSF) cortisol levels and to evaluate its role as a diagnostic and therapeutic marker in acute bacterial meningitis.

Materials and Methods:

Thirty patients with acute bacterial meningitis with no prior treatment were evaluated. Cortisol levels were compared with 20 patients with aseptic (viral) meningitis and 25 control subjects.

Results:

Mean CSF cortisol level was 13.85, 3.47, and 1.05 in bacterial meningitis, aseptic meningitis, and controls, respectively. Mean CSF cortisol level in bacterial meningitis was significantly higher as compared to controls (P < 0.001). There was significant difference in CSFcortisol levels in bacterial and aseptic meningitis (P < 0.001).

Conclusions:

Cortisol levels in CSF are highly elevated in patients with acute bacterial meningitis. This suggests that intrathecalcortisol may serve as a valuable, rapid, relatively inexpensive diagnostic marker in discriminatingbetween bacterial and aseptic meningitis. This helps in earlier institution of appropriate treatment and thereby decreasing morbidity and mortality.     

Evaluation of antioxidant status in children with acute bacterial meningitis and encephalitis

Antioxidant status was investigated in children with acute bacterial meningitis and encephalitis to investigate the possible role of free radicals in children with meningitis and encephalitis. Our study included 16 children with acute bacterial meningitis, 13 with encephalitis, and 17 control subjects. Serum ceruloplasmin, uric acid, albumin, bilirubin superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx) levels were studied in all subjects within 6 h of admission. There was a statistically significant difference between the groups for all parameters except for serum uric acid. All antioxidant activities except for albumin level were increased in the study groups. Albumin level was higher in the control group than those of meningitis and encephalitis groups. When the values of meningitis and encephalitis were compared, there was a statistically significant difference between the groups for serum SOD, GPx, ceruloplasmin, and albumin. In conclusion, our study showed that serum SOD, GPx, catalase, and ceruloplasmin were higher in children with acute bacterial meningitis and serum SOD, GPx, catalase, ceruloplasmin, and total bilirubin levels were increased in children with encephalitis. These findings suggest that antioxidant status was almost similar in both acute bacterial meningitis and encephalitis conditions in childhood.     

不同年龄小儿化脓性脑膜炎临床分析

目的 比较婴儿和年长儿化脓性脑膜炎(化脑)临床特点的差异.方法 对43例确诊为化脑的患儿临床资料进行回顾性分析.根据年龄分成2组,对2组原发病和基础疾病、临床表现、实验室检查、并发症及预后进行比较.结果 婴儿期化脑原发感染以肺炎多见,临床表现以前囟饱满或紧张、抽搐常见,外周血中性粒细胞百分比及脑脊液白细胞数低于年长儿,并发症及病死率均高于年长儿.结论 与年长儿相比,前囟饱满紧张为婴儿期的化脑常见而特有的体征,其次为抽搐,其他临床表现及脑脊液改变相对不典型,且并发症多、病死率高.应重视婴儿期化脑的早期诊断、治疗及随访.     

Current therapy of acute bacterial meningitis in children: Part II

Despite many advances in the past decade in the development of new antimicrobials, acute bacterial meningitis continues to have significant morbidity and mortality in infants and children. Regardless of the effectiveness of the antibiotic preparations, future improvements in outcome is most likely to occur because of more rapid diagnosis and initiation of therapy. The standard penicillins, chloramphenicol, and the aminoglycosides continue to hold an important place in treatment. The recent introduction of new extended spectrum penicillins, including piperacillin and mezlocillin, in addition to the development of the third generation cephalosporins, have expanded alternatives for treating bacterial meningitis. The most appropriate and effective antibiotic or combination of antibiotics must first be selected; thereafter, its use must be monitore to identify its beneficial effects as well as possible adverse effects.     

Current therapy of acute bacterial meningitis in children: Part I

The therapy of acute bacterial meningitis is changing rapidly because of the introduction of new antimicrobial agents and new techniques of vital function support. Proper spinal fluid examination, anticonvulsant drug administration, management of increased intracranial pressure, and correct choice of antibiotics are essential to achieve optimal therapy.