Cerebral herniation during bacterial meningitis in children.

OBJECTIVE--To see whether the incidence of cerebral herniation is increased immediately after lumbar puncture in children with bacterial meningitis and whether any children with herniation have normal results on cranial computed tomography. DESIGN--Retrospective review of case notes; computed tomograms were read again. SETTING--Large paediatric teaching hospital. SUBJECTS--445 children over 30 days old admitted to hospital with bacterial meningitis. MAIN OUTCOME MEASURES--Timing of herniation in relation to lumbar puncture; findings on computed tomography in children with herniation. RESULTS--Cerebral herniation was detected in 19 (4.3%) of the 445 children (21 episodes; herniation occurred twice in two children). Herniation occurred in 14 (45%) of the 31 children who died. Nineteen episodes of herniation occurred in the 17 children who had a lumbar puncture; 12 of the episodes occurred in the first 12 hours after the lumbar puncture and seven over six other 12 hour periods (odds ratio 32.6 (95% confidence interval 8.5 to 117.3); p < 0.001). The results of cranial computed tomography were normal in five (36%) of the 14 episodes of herniation in which scanning was performed at about the time of herniation. CONCLUSIONS--The temporal relation between lumbar puncture and herniation strongly suggests that a lumbar puncture may cause herniation in some patients, and normal results on computed tomography do not mean that it is safe to do a lumbar puncture in a child with bacterial meningitis.     

Lumbar puncture in spontaneous subarachnoid haemorrhage.

Seventy-four patients with proved spontaneous subarachnoid haemorrhage were studied. Sixty-four underwent computed tomography and 55 underwent lumbar puncture. Seven cases deteriorated dramatically after lumbar puncture, six of these showing evidence of cerebral dislocation on further investigation. Four of the seven had not undergone computed tomography and three underwent computed tomography after lumbar puncture. Computed tomography of the brain could determine patients at risk of coning. It is suggested that computed tomography is the investigation of choice after spontaneous subarachnoid haemorrhage and that lumbar puncture, if still then necessary, should be avoided until computed tomography has been undertaken.     

Computerized tomography in the diagnosis of hemorrhage caused by ruptured intracranial aneurysm]

The authors presented current views on usefulness of computed tomography (CT) for diagnosing the bleeding from a ruptured intracranial aneurysm. CT should be done in every such case, whereas the lumbar puncture remains the diagnostic method of choice, when CT is not available or in those patients in whom CT shows no haemorrhage. Sensitivity of CT decreases with time that elapsed from the stroke; false negative results are the least likely to occur within the first 48 hours after bleeding episode to subarachnoid space.     

Concentration Gradients of Free and Total γ-Aminobutyric Acid and Homocarnosine in Human CSF: Comparison of Suboccipital and Lumbar Sampling

Abstract: Concentrations of free and total γ-aminobutyric acid (GABA) and homocarnosine were determined in sequential aliquots of the first 30 ml of CSF obtained by lumbar puncture in five patients. Rostrocaudal gradients were calculated and compared to gradients estimated by determining concentrations of these substances in CSF obtained by simultaneous suboccipital and lumbar punctures in four more patients. In the lumbar fractions study, rostrocaudal mean gradients of 0.36, 36, and 21 pmol/ml for free GABA, total GABA, and homocarnosine, respectively, were calculated. In the suboccipital/lumbar study, gradients of 0.33, 30, and 24 pmol/ml for free GABA, total GABA, and homocarnosine, respectively, were estimated. These results indicate that valid comparison of CSF concentrations of these substances is restricted to similar fractions and suggest that in CSF the substances originate largely from brain rather than from peripheral sources.     

Leptomeningeal carcinomatosis presenting as eosinophilic meningitis

The case of a 67-year-old man with underlying carcinomatous meningitis who presented with meningismus and cerebrospinal fluid (CSF) eosinophilia is reported. CSF eosinophilia can reflect a number of underlying conditions; however, carcinomatous meningitis is not generally considered. In this case, studies for bacterial, fungal and parasitic agents were negative. Cytologic examination of a lumbar puncture specimen revealed malignant epithelial cells in an inflammatory background. When unexplained eosinophilia is found in the CSF, a thorough search for coincident meningeal carcinomatosis should be undertaken.     

Spinal puncture headache

Headache is the commonest complication of spinal puncture. There is no significant difference in the incidence of headache after lumbar puncture, whether or not the puncture is followed by injection of an anesthetic agent. The sequence of events leading to postlumbar puncture headaches is probably (1) decreased volume of cerebrospinal fluid with lowered pressure; (2) increased differential between the pressure of the cerebrospinal fluid and the intracranial venous pressure; (3) dilation of venous structures with increase in brain volume; and (4) production of tension on the pain sensitive areas in the cranium. Prevention of postlumbar puncture headache consists largely in attempts to avoid the development of the pressure differential between that of the cerebrospinal fluid and intracranial venous pressure. Treatment consists of analgesics, hydration and attempts to restore normal cerebrospinal fluid pressure.     

A Prospective Study of Mortality from Cryptococcal Meningitis following Treatment Induction with 1200mg Oral Fluconazole in Blantyre,Malawi

Objective

We have previously reported high ten-week mortality from cryptococcal meningitis in Malawian adults following treatment-induction with 800mg oral fluconazole (57% [33/58]). National guidelines in Malawi and other African countries now advocate an increased induction dose of 1200mg. We assessed whether this has improved outcomes.

Design

This was a prospective observational study of HIV-infected adults with cryptococcal meningitis confirmed by diagnostic lumbar puncture. Treatment was with fluconazole 1200mg/day for two weeks then 400mg/day for 8 weeks. Mortality within the first 10 weeks was the study end-point, and current results were compared with data from our prior patient cohort who started on fluconazole 800mg/day.

Results

47 participants received fluconazole monotherapy. Despite a treatment-induction dose of 1200mg, ten-week mortality remained 55% (26/47). This was no better than our previous study (Hazard Ratio [HR] of death on 1200mg vs. 800mg fluconazole: 1.29 (95% CI: 0.77–2.16, p = 0.332)). There was some evidence for improved survival in patients who had repeat lumbar punctures during early therapy to lower intracranial pressure (HR: 0.27 [95% CI: 0.07–1.03, p = 0.055]).

Conclusion

There remains an urgent need to identify more effective, affordable and deliverable regimens for cryptococcal meningitis.     

Measuring opening pressure in lumbar puncture--a new method]

Determination of the opening pressure (OP) during diagnostic lumbar puncture (LP) yields additional information that may impact on treatment and prognosis in disorders affecting the central nervous system (e.g. meningitis). Established methods contain systematic errors as well as risks to the patient. We therefore present a new procedure that allows measurement of the OP by timing the flow of cerebrospinal fluid through a capillary attached to an LP needle. A resistance located between needle and capillary slows down the flow of cerebrospinal fluid so that it becomes independent of the capillary forces acting on it. The time required for the fluid to travel between two marks on the capillary (defining a given volume) can be used to calculate the flow. Since the combined resistance of needle and resistance can be calibrated, the pressure driving the flow--in this case the opening pressure--can be calculated. A simple model was used to evaluate the impact of different resistances and different needles on OP determination. The effects of cellular elements and proteins in the CSF are discussed.     

The utility of the polymerase chain reaction assay for aetiologic definition of unspecified bacterial meningitis cases

Most patients with acute suppurative meningitis are otherwise healthy individuals with regard to immune mechanisms against invasive bacterial disease. This medical emergency is among the most dramatic and potentially ravaging diseases that affect humans, particularly young children. The illness often strikes suddenly, and can either result in death or leave the survivors with significant neurological dysfunctions. The demonstration of a bacterial aetiology is necessary for decisions regarding treatment and prophylaxis. Conventional bacteriological methods frequently fail to identify an agent, as a result of administration of antibiotics or delayed lumbar punctures. We investigated the major aetiologic sources of unspecified bacterial meningitis cases (G00.9, ISCD-10) by polymerase chain reaction (PCR)-based identification of Neisseria meningitidis (crgA), Streptococcus pneumoniae (ply) and Haemophilus influenzae (bexA) in cerebrospinal fluid samples. The multiplex PCR detected N. meningitidis in 92%, S. pneumoniae in 4% and H. influenzae in 1% of the 192 clinical samples assayed; 3% were negative for all three DNA targets. Bacterial DNA detection was found to be a valuable adjunct to enhance bacterial meningitis surveillance when the yield of specimens by culture is reduced. The implementation of PCR assays as a diagnostic procedure in Public Health Laboratories is perceived to be a significant advance in the investigation of bacterial meningitis.     

Effect of Cerebral Puncture on Brain Protein Synthesis in Adult and Young Rodents

Abstract: In adult mice cerebral puncture results in an inhibition of brain protein synthesis, as suggested previously by Dunn (1975). The inhibition is apparent within a few minutes but subsides by 15 min after puncture. The percent inhibition therefore depends on the length of time between the puncture and the measurement. Mice receiving a puncture were less active than controls, and a decrease in brain temperature was observed in these animals. The decrement is, however, too small to account for the inhibition of synthesis. Diphenylhydantoin had no effect on the inhibition. Cerebral puncture of young mouse (7-day-oId) or rat (8-day-old) brain induced no inhibition of brain protein synthesis.     

Mechanisms of lipid elevations associated with the treatment of patients with HIV infection

OBJECTIVE: Dyslipidemia and other metabolic abnormalities, which are associated with the use of highly active antiretroviral therapy (HAART) for the treatment of HIV infection, are of concern to patients and healthcare providers. The objective of this review is to present the current understanding of the dyslipidemia associated with the protease inhibitor (PI)-component of HAART: its possible origin, potential consequences, and management techniques. DATA SOURCES, STUDY SELECTION: Peer-reviewed, published literature was identified via MEDLINE. Other sources included abstracts from recent HIV-related conferences that presented data pertinent to the topic. Studies were selected based on their impact on our understanding of HIV infection and its treatment. DATA EXTRACTION, SYNTHESIS: Relevant portions of the publications considered were compiled and conclusions were drawn based on the clinical experience of the author. CONCLUSION: Dyslipidemia associated with current PIs should be a serious consideration when initiating long-term treatment of HIV infection. Current management techniques that include lipid-lowering agents may be improved and streamlined by incorporating a lipid-friendly PI into HAART.     

Cost Effectiveness of Cryptococcal Antigen Screening as a Strategy to Prevent HIV-Associated Cryptococcal Meningitis in South Africa

Objectives

Cryptococcal meningitis (CM)-related mortality may be prevented by screening patients for sub-clinical cryptococcal antigenaemia (CRAG) at antiretroviral-therapy (ART) initiation and pre-emptively treating those testing positive. Prior to programmatic implementation in South Africa we performed a cost-effectiveness analysis of alternative preventive strategies for CM.

Design

Cost-effectiveness analysis.

Methods

Using South African data we modelled the cost-effectiveness of four strategies for patients with CD4 cell-counts <100 cells/µl starting ART 1) no screening or prophylaxis (standard of care), 2) universal primary fluconazole prophylaxis, 3) CRAG screening with fluconazole treatment if antigen-positive, 4) CRAG screening with lumbar puncture if antigen-positive and either amphotericin-B for those with CNS disease or fluconazole for those without. Analysis was limited to the first year of ART.

Results

The least costly strategy was CRAG screening followed by high-dose fluconazole treatment of all CRAG-positive individuals. This strategy dominated the standard of care at CRAG prevalence ≥0.6%. Although CRAG screening followed by lumbar puncture in all antigen-positive individuals was the most effective strategy clinically, the incremental benefit of LPs and amphotericin therapy for those with CNS disease was small and additional costs were large (US$158 versus US$51per person year; incremental cost effectiveness ratio(ICER) US$889,267 per life year gained). Both CRAG screening strategies are less costly and more clinically effective than current practice. Primary prophylaxis is more effective than current practice, but relatively cost-ineffective (ICER US$20,495).

Conclusions

CRAG screening would be a cost-effective strategy to prevent CM-related mortality among patients initiating ART in South Africa. These findings provide further justification for programmatic implementation of CRAG screening.     

脑脊液检查在早产儿及足月儿细菌性脑膜炎的诊断价值

目的:评价脑脊液检查在早产儿及足月儿细菌性脑膜炎诊断中的价值。方法:选取2014年6月1日至2016年12月31日上海市儿童医院新生儿科收治的行腰椎穿刺检查的447例新生儿,回顾性分析新生儿的一般资料、脑脊液常规生化、培养等指标,根据胎龄将患儿分为早产儿167例与足月儿280例,再根据有无患发细菌性脑膜炎分为早产儿细菌性脑膜炎27例(早产儿观察组)、早产儿非细菌性脑膜炎140例(早产儿对照组)、足月儿细菌性脑膜炎38例(足月儿观察组)、足月儿非细菌性脑膜炎242例(足月儿对照组),采用受试者工作特征(ROC)曲线评估蛋白定量、白细胞计数、葡萄糖对早产儿及足月儿细菌性脑膜炎的诊断价值。结果:与同组对照组相比,足月儿观察组和早产儿观察组蛋白定量和白细胞计数均明显升高,而葡萄糖含量显著下降,且差异均具有统计学意义(P0.05);本研究65例细菌性脑膜炎患儿脑脊液培养分离出11株细菌(16.9%)。足月儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎的ROC曲线下面积分别为0.995、0.846、0.703。早产儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎ROC曲线下面积分别为0.970、0.711、0.705。结论:脑脊液白细胞计数、蛋白定量在足月儿和早产儿细菌性脑膜炎中具有较高的诊断价值。     

Noninvasive monitoring of pneumococcal meningitis and evaluation of treatment efficacy in an experimental mouse model

Noninvasive real-time in vivo bioluminescent imaging was used to assess the spread of Streptococcus pneumoniae throughout the spinal cord and brain during the acute stages of bacterial meningitis. A mouse model was established by lumbar (LP) or intracisternal (IC) injection of bioluminescent S. pneumoniae into the subarachnoid space. Bacteria replicated initially at the site of inoculation and spread progressively from the spinal cord to the brain or from the brain down to the cervical part of the spinal column and to the lower vertebral levels. After 24 hr, animals showed strong bioluminescent signals throughout the spinal canal, indicating acute meningitis of the intracranial and intraspinal meninges. A decline in bacterial cell viability, as judged by a reduction in the bioluminescent signal, was observed over time in animals treated with ceftriaxone, but not in untreated groups. Mice treated with the antibiotic survived infection, whereas all mice in untreated groups became moribund, first in the IC group then in the LP group. No untreated animal survived beyond 48 hr after induction of infection. Colony counts of infected cerebrospinal fluid (CSF) correlated positively with bioluminescent signals. This methodology is especially appealing because it allows detecting infected mice as early as 3 hr after inoculation, provide temporal, sequential, and spatial distribution of bacteria within the brain and spinal cord throughout the entire disease process and the rapid monitoring of treatment efficacy in a nondestructive manner. Moreover, it avoids the need to sacrifice the animals for CSF sampling and the potential manipulative damage that can occur with other conventional methods.     

Meta-analysis of benzodiazepine use in the treatment of acute alcohol withdrawal

OBJECTIVE: To analyse the evidence for the efficacy and potential harmful effects of benzodiazepines compared with other therapies in the treatment of acute alcohol withdrawal. DATA SOURCES: MEDLINE and the Cochrane Controlled Trials Registry were searched for English-language articles published from 1966 to December 1997 that described randomized controlled trials (RCTs) of benzodiazepines in the treatment of acute alcohol withdrawal. Key words included "benzodiazepines" (exploded) and "randomized controlled trial." Bibliographies of relevant articles were reviewed for additional RCTs, and manufacturers of benzodiazepines were asked to submit additional RCT reports not in the literature. STUDY SELECTION: Articles were considered for the meta-analysis if they were RCTs involving patients experiencing acute alcohol withdrawal and comparing a benzodiazepine available in Canada with placebo or an active control drug. Of the original 23 trials identified, 11 met these criteria, representing a total of 1286 patients. DATA EXTRACTION: Data were extracted regarding the participants, the setting, details of the intervention, the outcomes (including adverse effects) and the methodologic quality of the studies. DATA SYNTHESIS: The meta-analysis of benefit (therapeutic success within 2 days) showed that benzodiazepines were superior to placebo (common odds ratio [OR] 3.28, 95% confidence interval [CI] 1.30-8.28). Data on comparisons between benzodiazepines and other drugs, including beta-blockers, carbamazepine and clonidine, could not be pooled, but none of the alternative drugs was found to be clearly more beneficial than the benzodiazepines. The meta-analysis of harm revealed no significant difference between benzodiazepines and alternative drugs in terms of adverse events (common OR 0.67, 95% CI 0.34-1.32) or dropout rates (common OR 0.68, 95% CI 0.47-0.97). INTERPRETATION: Benzodiazepines should remain the drugs of choice for the treatment of acute alcohol withdrawal.     

Calculating lumbar puncture depth in children

Lumbar puncture was performed in 195 children and the depth of needle was recorded. Our results show that the depth of lumbar puncture necessary to obtain uncontaminated cerebrospinal fluid correlates best with the child's weight. The simple formula: mean depth of insertion (cm) = 1.3 + 0.07 x body weight (kg), can be used to estimate the depth of lumbar puncture of children older than 3 months. The depths of lumbar puncture of children younger than 3 months are mostly 1.0-1.5 cm.     

The reuse of hemodialyzers: an assessment of safety and potential savings.

OBJECTIVE: To evaluate the safety and potential cost savings of hemodialyzer reuse. DATA SOURCES: All English and French articles published from 1960 to 1991 related to hemodialyzer reuse (retrieved through an Index Medicus and MEDLINE search [corrected]), the indexes of eight North American journals from 1960 onward, conference proceedings, association guidelines, and US and Canadian laws and regulations. RESULTS: For health care personnel the reuse of hemodialyzers did not entail any increased risk of infection or exposure to toxic substances if proper control measures were taken. For patients there was no evidence to suggest any excess risk of complications or death as long as precise and appropriate procedures are observed. The "first-use syndrome" can be prevented and should no longer be considered as a reason to favour reuse. A cost-minimization analysis indicated that five uses might save up to $3629 per patient yearly. Thus, the adoption of a policy of reuse in Canada for all eligible patients undergoing long-term hemodialysis could result in direct savings of about $5.8 to $8.9 million per year. CONCLUSION: The health risks associated with hemodialyzer reuse can be reduced to acceptable levels through the rigorous observance of proper quality-assurance and quality-control measures and the use of automated reconditioning equipment. Such a policy could achieve modest savings for the health care system. A decision to reuse should be formally adopted by the institution and accompanied by a precise definition of the standards of quality assurance and control.     

一种Beagle犬腰椎穿刺置管术介绍

目的建立一种新的Beagle犬脑脊液连续留取的方法。方法通过氯胺酮麻醉进行腰椎穿刺后置管可连续留取脑脊液。结果腰椎穿刺置管后成功连续留取清亮脑脊液超过48h。结论腰椎穿刺置管连续留取脑脊液简单、有效。     

Coccidioidal Meningitis—Intrathecal Treatment with Hyperbaric Amphotericin B

The localization of coccidioidal meningitis in the basilar regions, with resultant hydrocephalus and uniformly fatal outcome, has necessitated intrathecal injection of amphotericin B via cisternal puncture or subcutaneous ventricular reservoir for successful therapy. A simpler form of treatment is described here, whereby amphotericin B diluted in 10 percent glucose solution is injected via lumbar puncture, and delivered to the base of the skull by tilting the patient to a head-down position. A simultaneously performed hyperbaric cisternogram with ¹³¹I-serum albumin has demonstrated satisfactory migration of the injected bolus to the occiput. This method of administration resulted in successful suppressive treatment of one patient, including two years of follow-up without serious sequelae or relapse.     

Higher Orexin A levels in lumbar compared to ventricular CSF: A study in idiopathic normal pressure hydrocephalus

Orexin A (ORX-A) is implicated in the regulation of various physiological processes, including sleep/wake cycles and reward/motivation. The hypothalamic ORX-A neurons project throughout the brain and spinal cord. In the present study we established and compared ORX-A levels in lumbar and ventricular cerebrospinal fluid (CSF) samples, drawn from idiopathic normal pressure hydrocephalus (INPH) patients, during respectively, lumbar puncture and shunt placement. Ventricular and lumbar CSF levels of total protein and of the dopamine, serotonin and norepinephrine metabolites HVA, 5-HIAA and MHPG respectively, were also estimated. ORX-A was quantified using a commercially available radioimmunoassay kit. Neurotransmitter metabolites were quantified by high performance liquid chromatography. Expectedly, HVA and 5-HIAA levels were significantly higher and total protein levels lower in ventricular compared to lumbar CSF while there were no differences in MHPG levels. However, in contrast to HVA and 5-HIAA and similar to total protein, lumbar ORX-A levels were significantly higher than ventricular levels. The higher lumbar compared to ventricular ORX-A levels may reflect elevated contributions from the spinal cord. The finding of a ventriculo-lumbar difference for ORX-A should be considered in studies utilizing its CSF levels in assessing Orexin system status.