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.     

76例儿童隐球菌性脑膜炎临床分析

目的分析儿童隐球菌性脑膜炎临床特点。方法回顾性分析76例隐球菌性脑膜炎患儿临床资料。结果男47例,女29例,平均年龄(6.34±3.67)岁;主要临床表现为发热(100%)、头痛(78.95%)、呕吐(81.58%);首次脑脊液墨汁染色阳性46例(60.53%),首次脑脊液真菌培养阳性21例(27.63%),两性霉素B联合5-氟胞嘧啶抗真菌治疗好转率(74.19%),两性霉素B联合氟康唑治疗好转率(62.96%),差异无统计学意义(P=0.75)。结论儿童隐球菌性脑膜炎极易误诊、漏诊,反复、多次腰穿有助于早期诊断;两性霉素B联合5-氟胞嘧啶是抗真菌治疗首选方案,早期诊断、积极降颅压是改善预后的关键。     

Diagnosis of Streptococcus pneumoniae meningitis by polymerase chain reaction amplification of the gene for pneumolysin

Diagnosis of bacterial meningitis has long been based on classical methods of Gram stain, serological tests, and culture of cerebrospinal fluid (CSF). The performance of these methods, especially culture and direct smear is thwarted by failure to detect bacteria following administration of antimicrobial agents and reluctance to performance lumbar punctures at admission. Indeed, patients with meningitis frequently receive antibiotics orally or by injection before the diagnosis is suspected or established Thus an alternative method has become necessary to help clinicians and epidemiologists to management and control of bacterial meningitis. We evaluate the application of a polymerase chain reaction-based (PCR) assay for amplification of pneumolysin gene (ply) to diagnosis of Streptococcus pneumoniae meningitis. The PCR assay sensitivity for CSF was 96% (95% confidence interval, CI, 90-99%) compared to a sensitivity of 59% for culture (95% CI 49-69%), 66% for Gram stain (95% CI 56-74%), and 78% for latex agglutination test (95% CI 69-86%); PCR specificity was 100% (95% CI 83-100%). PCR results were available within 4 h of the start of the assay. This molecular approach proved to be reliable and useful to identify this bacterium compared with other classical laboratory methods for identification of bacterial meningitis pathogens.     

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.     

Computed tomography before lumbar puncture in acute meningitis: a review of the risks and benefits.

OBJECTIVE: To determine the indications, if any, for routine computed tomography (CT) of the brain before lumbar puncture in the management of acute meningitis. DATA SOURCES: Original research papers, reviews and editorials published in English from 1965 to 1991 were retrieved from MEDLINE. The bibliographies of these articles and of numerous standard texts were examined for pertinent references. A survey of local neurologists was conducted, and legal opinion was sought from the Canadian Medical Protective Association. DATA EXTRACTION: There were no studies directly assessing the risks of lumbar puncture in meningitis; however, all sources were culled for other pertinent information. RESULTS: No cases could be found of patients with acute meningitis deteriorating as a result of lumbar puncture. The neurologic consensus refuted the need for CT in typical acute meningitis. All sources stressed speedy lumbar puncture and the early institution of appropriate antibiotic therapy to minimize the severity of the illness and the risk of death. CONCLUSIONS: (a) There is no evidence to recommend CT of the brain before lumbar puncture in acute meningitis unless the patient shows atypical features, (b) for patients with papilledema the risks associated with lumbar puncture are 10 to 20 times lower than the risks associated with acute bacterial meningitis alone, (c) CT may be necessary if there is no prompt response to therapy for meningitis or if complications are suspected, (d) the inability to visualize the optic fundi because of cataracts or senile miosis is not an indication for CT and (e) there are no Canadian legal precedents suggesting liability if physicians fail to perform CT in cases of meningitis.     

Correlation between culture of Mycobacterium tuberculosis and antimycobacterial antibody in lumbar, ventricular and cisternal cerebrospinal fluids of patients with tuberculous meningitis.

In this study positive culture for M. tuberculosis were obtained, 20% in lumbar cerebrospinal fluid (CSF), 75% in ventricular CSF and 87.5% in cisternal CSFs of patients with tuberculous meningitis. Low culture positivity in lumbar CSF is due to the low density of circulating tubercle bacilli in lumbar CSF than in cisternal or ventricular CSFs. However antimycobacterial antibody in lumbar, cisternal and ventricular CSFs circulate in significant titres and are not statistically different from one another. Since specimens of CSF can not be obtained from cisternal or ventricular routes for the routine bacteriological investigations in patients with tuberculous meningitis, detection of antimycobacterial antibody of M. tuberculosis antigen 5 in lumbar CSF by an indirect ELISA may be considered as an aid for the diagnosis of tuberculous meningitis, particularly when repeated CSF cultures are negative for M. tuberculosis.     

Acute Effect of Protein or Carbohydrate Breakfasts on Human Cerebrospinal Fluid Monoamine Precursor and Metabolite Levels

Patients with normal pressure hydrocephalus who had three lumbar punctures during 1 week ingested either water, a protein breakfast, or a carbohydrate breakfast 2.5 h before each of the lumbar punctures. The CSF was analyzed for biogenic amine precursors and metabolites. The protein meal raised CSF tyrosine levels, a finding consistent with animal data, but did not alter those of tryptophan or any of the biogenic amine metabolites. The carbohydrate meal increased CSF 3-methoxy-4-hydroxyphenylethylene glycol, an unexplained finding. The carbohydrate meal did not affect CSF tryptophan, tyrosine, 5-hydroxyindoleacetic acid, or homovanillic acid. Our results support the idea that in humans protein or carbohydrate meals do not alter plasma amino acid levels sufficiently to cause appreciable changes in CNS tryptophan levels or 5-hydroxytryptamine synthesis.     

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.     

腰椎置管治疗隐球菌性脑膜炎4例并文献复习

目的 观察早期腰椎置管引流加鞘内注射两性霉素B治疗伴有恶性高颅压隐球菌性脑膜炎的临床效果及探讨临床应用的可行性.方法 详细分析和归纳整理了我科应用腰椎置管法治疗的4例隐球菌性脑膜炎患者的临床资料.结果 4例患者经早期腰椎置管引流加鞘内注射两性霉素B治疗后临床症状迅速改善.经联合治疗后,痊愈3例,好转1例,4例患者随访至今均无复发.结论 早期腰椎置管引流加鞘内注射两性霉素B治疗隐球菌性脑膜炎能有效的降低隐球菌脑膜炎患者的高颅压,改善临床症状,提高疗效.     

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.     

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.     

Performance of Cryptococcal Antigen Lateral Flow Assay Using Saliva in Ugandans with CD4 <100

Background

Cryptococcal meningitis can best be diagnosed by cerebrospinal fluid India ink microscopy, cryptococcal antigen detection, or culture. These require invasive lumbar punctures. The utility of cryptococcal antigen detection in saliva is unknown. We evaluated the diagnostic performance of the point-of-care cryptococcal antigen lateral flow assay (CrAg LFA) in saliva.

Methods

We screened HIV-infected, antiretroviral therapy naïve persons with symptomatic meningitis (n = 130) and asymptomatic persons with CD4+<100 cells/µL entering into HIV care (n = 399) in Kampala, Uganda. The diagnostic performance of testing saliva was compared to serum/plasma cryptococcal antigen as the reference standard.

Results

The saliva lateral flow assay performance was overall more sensitive in symptomatic patients (88%) than in asymptomatic patients (27%). The specificity of saliva lateral flow assay was excellent at 97.8% in the symptomatic patients and 100% in asymptomatic patients. The degree of accuracy of saliva in diagnosing cryptococcosis and the level of agreement between the two sample types was better in symptomatic patients (C-statistic 92.9, κ-0.82) than in asymptomatic patients (C-statistic 63.5, κ-0.41). Persons with false negative salvia CrAg tests had lower levels of peripheral blood CrAg titers (P<0.001).

Conclusion

There was poor diagnostic performance in testing saliva for cryptococcal antigen, particularly among asymptomatic persons screened for preemptive treatment of cryptococcosis.     

Obituaries

Pseudotumour cerebri is a disorder characterized by elevated intracranial pressure in the absence of hydrocephalus and intracranial mass lesions. The cause of this disease remains obscure but has been related to diverse underlying conditions. We report a patient with pseudotumour cerebri, polyarthritis, urticaria, hypocomplementemia and cryoglobulinemia. Serial lumbar punctures were unsuccessful in lowering the cerebrospinal fluid (CSF) pressure. A trial of prednisone, 40 mg daily for 4 weeks, resulted in clinical improvement but was ineffective in lowering the CSF pressure. Circulating immune complexes and complement activation may have played a role in the development of increased intracranial pressure. Cryoglobulinemia should be added to the list of disorders associated with pseudotumour cerebri.     

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。     

Host-marking pheromone and use of previously established oviposition sites by the mediterranean fruit fly (Diptera: Tephritidae)

Under controlled conditions, the Mediterranean fruit fly, Ceratitis capitata(Wiedemann) preferred to initiate oviposition into preexisting, naturally formed oviposition punctures in a host fruit, kumquat (Fortunella japonica),over establishing new sites on the fruit. This preference was expressed despite the presence of naturally deposited host-marking pheromone (HMP)shown previously to deter oviposition. An almost-identical preference for existing punctures was expressed when females were presented with fruit bearing artificially made punctures on which HMP had been naturally deposited. Using artificial punctures and HMP extracts, the occurrence of punctures was manipulated independently of the presence of HMP.Under field-cage conditions, we found that (1) punctures stimulated egg-laying on kumquats, regardless of HMP treatment; (2) HMP extract inhibited egg-laying, regardless of the occurrence of punctures; and (3) the extent to which HMP inhibited egg-laying was greater on fruit free of punctures than on fruit bearing them. The physiological, evolutionary, and pest management implications of these results are discussed.     

Cerebrospinal fluid cytology diagnosis of meningeal carcinomatosis in patients with small-cell carcinoma of the lung. A study of interobserver and intraobserver variability

The interobserver and intraobserver variation in the cytologic diagnosis of malignancy was determined in 62 cerebrospinal fluid (CSF) specimens from 46 patients with small-cell carcinoma of the lung. In all patients, lumbar puncture was carried out because of suspected central nervous system metastases. Forty CSF specimens from 26 patients with meningeal carcinomatosis and thus with a high probability of a positive CSF cytology were mixed with 22 specimens from 20 patients without meningeal carcinomatosis. The slides were evaluated blindly by two observers, one of whom evaluated all specimens on two separate occasions; only positive, negative and suspicious conclusions were permitted. The consistency of the intraobserver and interobserver conclusions on the initial CSF specimen in each case was 87%. In 13% of the initial CSF specimens in each case, a suspicious conclusion was reached in one of the three evaluations. For all 62 CSFs, the intraobserver and interobserver disagreement was 2% and 3%, respectively. In the first and second evaluations by the one observer and the single evaluation by the other, 17 (65%), 15 (58%) and 12 (46%), respectively, of the 26 "high probability" patients were found to have malignant cells in the CSF. CSF cytology was negative in all 20 patients without meningeal carcinomatosis. Of 10 patients with autopsy-proven meningeal carcinomatosis, 40% were not diagnosed while alive. Multiple CSFs from repeated lumbar punctures increased the number of positive evaluations by 30%. At least 60% of those patients with a suspicious CSF cytology did in fact have meningeal carcinomatosis. On the other hand, 30% of the patients with a positive lumbar puncture had a subsequent negative one.     

Deposition and longevity of oviposition-deterring pheromone in the cabbage seed weevil

Abstract The cabbage seed weevil ( Ceutorhynchus assimilis Payk.) lays eggs singly into pods of oilseed rape ( Brassica napus L.) through punctures bored with the mouthparts, preferring pods not recently used for oviposition. A simple new choice test has been used to test individual components of egg-laying behaviour for their effect on oviposition site selection. It is confirmed that an oviposition-deterring pheromone (ODP) is deposited during abdomen brushing of the pod which follows egg-laying. Neither pin punctures, weevil feeding punctures, oviposition punctures nor eggs had any deterrent effect. Pods walked on by female weevils were not avoided by those laying eggs. Observations suggest that the ODP is sensed by contact chemoreceptors on the antennae. The deterrent effect lasted only 1–2 h. The implications of these findings on the adaptive significance of the pheromone and its possible use in pest control are discussed.     

Impairment of Blood-Cerebrospinal Fluid Barrier in Multiple Sclerosis

The blood-CSF barrier (BCB) function in active multiple sclerosis (MS) was studied by means of CSF proteins analysis using disc electrophoresis and immunofixation. Forty-five CSF samples were obtained by repeat lumbar punctures at various intervals, from four autopsy-proven cases and three male and nine female patients with clinically definite MS. When total protein content was increased, the percentages of prealbumin and tau fraction were decreased significantly in association with the presence of haptoglobin (Hp) polymers in nearly all the samples, as a result of increased permeability of the BCB. Even when the total protein content was normal, Hp polymers were detected in 56% of the samples, and the tau fraction tended to be decreased. Monoclonal immunoglobulin and Hp polymers were both recognized in some cases. The results suggested a more frequent occurrence of BCB impairment in MS than had formerly been revealed by CSF albumin analysis, and accorded with the recent reports of contrast-enhancing lesions of MS brain in computerized tomography.     

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.     

Mechanism and effectiveness of safflower oil against female Queensland fruit fly Bactrocera tryoni

Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), infests many horticultural fruit crops in the eastern part of Australia. Farmers usually apply synthetic insecticides to control this pest. Little is known on the use of plant products especially vegetable oils for fruit fly control although they are considered to be safer than synthetic insecticides. In this study, safflower oil was investigated for its mechanism and effectiveness against female B. tryoni. In a laboratory test, safflower oil treatments (2.5 and 5.0 ml l^?1) reduced the number of fly punctures on treated artificial fruits, no matter whether pre‐punctures were present or absent. Safflower oil treatments also reduced the number of fly landings and eggs laid, but only when the treated artificial fruits were without pre‐punctures. These results confirmed that safflower oil is active against female B. tryoni mainly by preventing this fruit fly from making oviposition punctures, not by discouraging them from depositing eggs or by repelling them. The slippery nature of safflower oil is considered to be responsible for a reduction in the susceptibility of artificial fruit to fruit fly punctures. Further investigation using fruit‐bearing tomato plants (a no‐choice test) in a glasshouse situation revealed that safflower oil application at concentrations of 10 and 15 ml l^?1 reduced the number of oviposition punctures but failed to reduce the number of eggs laid. To increase efficacy of safflower oil under field conditions, multiple tools may be needed to reduce fruit fly populations and oviposition behaviour, such as the addition of trap‐crops, provision of artificial oviposition sites, or mixing the insecticides with the oil.