Latex agglutination test: An adjunct to the laboratory diagnosis of pyogenic bacterial meningitis

Gram stain, culture and latex agglutination test (LAT) of cerebrospinal flud were performed in 50 patients clinically diagnosed as suffering from pyogenic bacterial meningitus. Using all the three techniques, an aetiological diagnosis was made in 27 (54%).Neisseria meningitidis, Streptococcus pneumoniae and H. influenzae were the infecting organisms in 21 cases (44%). There were 12 additional cases in which LAT was the only clue to the diagnosis as compared to conventional techniques.Propionibacterium acnes was isolated from one case of anaerobic meningitis. It is concluded that LAT is an adjunct to conventional techniques in the diagnosis of pyogenic bacterial meningitis, where the latter tests fail.     

脑脊液乳胶凝集试验在儿童新型隐球菌性脑膜炎诊断和治疗中的应用

目的：探讨脑脊液乳胶凝集试验在隐球菌性脑膜炎诊断和治疗中的应用价值。方法：回顾性分析10例新型隐球菌性脑膜炎患儿的临床资料。通过临床表现,结合脑脊液墨汁染色、乳胶凝集试验与真菌培养,确诊新型隐球菌脑膜炎。随访2~4年抗真菌治疗的效果和乳胶凝集试验滴度变化。结果：10例患儿中,首次脑脊液检查乳胶凝聚试验和/或墨汁染色阳性者8例（乳胶凝集试验滴度1∶64~1∶1024）;另2例中1例在第4次检查时始出现乳胶凝集试验阳性（滴度1∶256）,1例在第11次检查时墨汁染色阳性而确诊。经正规抗真菌治疗后,6例痊愈,2例死亡,2例失访。治疗后6个月、1年、2年和4年脑脊液乳胶凝集试验仍阳性（滴度1∶2~1∶16）者分别有6例、3例、2例和1例。结论：脑脊液乳胶凝集试验对于新型隐球菌性脑膜炎的快速诊断具有重要价值,但不宜作为停止抗真菌治疗的依据。     

Controversies in the management of bacterial meningitis

Bacterial meningitis is an important infection of childhood with significant morbidity and mortality, and clinicians are faced with controversies over steroid use and fluid restriction in its initial management because the standard of practice is not clear. A 1999 survey of paediatric infectious diseases specialists demonstrated that only 56% of respondents recommended dexamethasone for Haemophilus influenzae type b meningitis and only 34% recommended dexamethasone for Streptococcus pneumoniae meningitis, despite recommendations for dexamethasone in the 1997 Red Book. The present article illustrates a typical case presentation of bacterial meningitis, and discusses dexamethasone use and fluid restriction. The use of intravenous fluid therapy is also reviewed, based on results from the single prospective randomized clinical trial in this area.     

Acute endocarditis following pneumococcal meningitis

Acute mitral valve endocarditis, presenting as a new murmur and haematuria, complicated pneumococcal meningitis in a 20-month-old child with a normal heart. Awareness of this rare complication of pneumococcaemia and its early diagnosis, using cross-sectional echocardiography, improves the clinical outcome of a condition associated with a high mortality.     

Bacterial meningitis: Mechanisms of disease and therapy

Bacterial meningitis continues to be a serious infectious disease with a high morbidity and mortality in young children. Early recognition and initiation of adequate treatment are the major determinants for a good outcome. Recent advances in our understanding of the host inflammatory response by cytokines may result in the use of new therapeutic strategies. Such modulation of the inflammatory response may reduce the incidence of sequelae and death. The use of steroids as adjunctive therapy in children with bacterial meningitis probably has beneficial effects although the available data are still controversial. Additionally, studies in experimental meningitis models indicate that non-steroidal anti-inflammatory drugs and monoclonal antibodies against bacterial products, cytokines and CD18 on leucocytes reduce the extent of the meningeal inflammation. Human studies to evaluate the efficacy of these immune modulators are expected to start soon. However, prevention of bacterial meningitis by conjugate vaccines againstStreptococcus pneumoniae andNeisseria meningitidis will be the most promising development in the next decade.     

Detection of tubercule antigen in cerebrospinal fluids by ELISA for diagnosis of tuberculous meningitis

An Enzyme Linked Immunosorbent Assay (ELISA) was standardised to detect the presence of tubercule antigen in cerebrospinal fluids from patients with meningitis. CSF samples from clinically suspected cases of tuberculous meningitis, culture proven pyogenic meningitis and non-bacterial aseptic central nervous system (CNS) disorders were tested by ELISA to demonstrate its potential utility for routine diagnostic purpose. Tubercule antigen was detected in 73% cases of tuberculous meningitis and was absent in pyogenic and other non-bacterial CNS disorder cases. The test appears to be a promising approach for a definitive diagnosis of tuberculous meningitis.     

Bacterial meningitis: is there a “best” antimicrobial therapy?

The introduction of several cephalosporins into pediatric practice has provided the physician with a number of choices in the treatment of neonatal and childhood meningitis. Adequate studies are available to indicate that these new drugs are as effective as traditional treatments in terms of survival and major neurologic sequelae but it is not known whether the results are worse or better as far as the incidence of more subtle neurologic changes is concerned. The advantages of the cephalosporins in treatment of childhood meningitis are that they permit single drug therapy, the risks of drug toxicity are reduced, and the problems of penicillin-tolerant pneumococci and ampicillin/chloramphenicol-resistantH. influenzae are avoided. When used in the treatment of neonatal disease, the cephalosporins have the advantage of lower toxicity than the aminoglycosides, generally making blood drug level determinations unnecessary, and are effective against strains of bacteria that have become resistant to the latter drugs.     

Uncommon clinical presentation of a common bug: Group A Streptococcus meningitis

Group A Streptococcus (GAS) is a common pathogen in paediatric infections. However, it is a rare etiologic agent of bacterial meningitis. We describe a case of Streptococcus pyogenes meningitis complicated by sensorineural hearing loss in an immunocompetent 7-year-old boy. Clinicians should be aware of GAS as a potential cause of paediatric meningitis, especially with prominent symptoms suggestive of frontal sinusitis. Meningitis caused by GAS has been shown to be associated with significant mortality and morbidity, including neurological complications. Early screening for sensorineural hearing loss in patients with GAS meningitis can facilitate timely cochlear implant.     

Sonographic findings in bacterial meningitis in neonates and young infants

Cranial sonography plays an important role in the initial evaluation of infants with suspected bacterial meningitis and in monitoring for complications of the disease. Echogenic widening of the brain sulci, meningeal thickening and hyperemia suggest the diagnosis in an at-risk population. Sonography can identify the presence of extra-axial fluid collections, and color Doppler sonography can be very helpful in differentiating benign enlargement of subarachnoid spaces from subdural effusions. Intraventricular debris and stranding, and an irregular and echogenic ependyma are highly suggestive findings associated with ventriculitis. Sonography can play an important role in the detection of postinfectious hydrocephalus, in the determination of the level of obstruction, and in the evaluation of intracranial compliance. Focal or diffuse parenchymal involvement can represent parenchymal involvement by cerebritis, infarction, secondary hemorrhage or early abscess.     

Helicobacter pylori stool antigen test

Objective :Helicobacter pylori (H.pylori) infection is usually acquired in early childhood. Invasive techniques used for diagnosis ofH.pylori infection require endoscopic examination which is expensive and inconvenient and may cause complications. the aim of this study was to evaluate the performance of a new noninvasive diagnostic method, stool antigen test forH.pylori in untreated children with recurrent abdominal pain.Methods: Eighty children (35 female, 45 male) who have undergone upper gastrointestinal endoscopy due to recurrent abdominal pain were included in the study. theH.pylori stool antigen test (HpSA) is based on a sandwich enzyme immunoassay with antigen detection. HpSA sensitivity, specificity, and positive and negative predictive values were determined with reference to the results of both histology and rapid urease test as a gold standard (H. pylori status).Results: While 49 of the 80 children (61%) tested were positive forH.pylori according to the results of both histology and rapid urease test, 28 children had negativeH.pylori status. Among those 49 children, 48 were found to be positive by HpSA. Of 28 patients with negativeH.pylori status, 28 were H.py/ori-negative also in the stool test. the sensitivity, specificity, and positive and negative predictive values of HpSA were found to be 98%, 100%, 100%, and 96.5%, respectively.Conclusion: these findings have demonstrated that HpSA as a relatively simple, inexpensive and time saving noninvasive test is a reliable method for detection ofH.pylori infections in children.     

Prediction of bacterial meningitis in children with meningeal signs: reduction of lumbar punctures

Physicians often have to perform a lumbar puncture to ascertain the diagnosis in patients with meningeal signs, because of the serious consequences of missing bacterial meningitis The aim of this study was to derive and validate a clinical rule to predict bacterial meningitis in children with meningeal signs, to guide decisions on the performance of lumbar punctures. Information was collected from records of patients (aged 1 mo to 15 y) consulting the emergency department of the Sophia Children's Hospital between 1988 and 1998 with meningeal signs. Bacterial meningitis was defined as cerebrospinal fluid (CSF) leucocyte count >5 cells μl^?1 with a positive bacterial culture of CSF or blood. The diagnostic value of predictors was judged using multivariate logistic modelling and area under the receiver operating characteristic curves (ROC area). In the derivation set (286 patients, years 1988–1995) the duration of the main complaint, vomiting, meningeal irritation, cyanosis, petechiae and disturbed consciousness were independent clinical predictors of bacterial meningitis. The ROC area of this model was 0.92. The only independent predictor from subsequent laboratory tests was the serum C‐reactive protein concentration, increasing the ROC area to 0.95. Without missing a single case, this final model identified 99 patients (35%) without bacterial meningitis. Validation on 74 consecutive patients in 3 subsequent years (1996–1998) yielded similar results. Conclusion: This prediction rule identifies about 35% of the patients with meningeal signs in whom a lumbar puncture can be withheld without missing a single case of bacterial meningitis. For the individual patient this prediction rule is valuable in deciding whether or not to perform a lumbar puncture.     

降钙素原对儿童细菌性脑膜炎鉴别诊断的meta分析

目的 探讨降钙素原(PCT)对儿童细菌性脑膜炎的诊断价值。方法 采用计算机检索获得PCT对儿童细菌性脑膜炎的诊断性研究文献,检索时间为建库至2013年7月,按照QUADAS 标准评价纳入文献质量。采用Meta-Disc 1.4 软件进行Meta分析,对敏感度、特异度、阳性似然比、阴性似然比进行汇总和异质性检验,绘制综合受试者特征曲线（SROC）,行敏感性分析和异质性原因分析。使用Stata 12.0软件判断发表偏移并绘制漏斗图。结果 12篇文献进入Meta分析（中文5篇,英文7篇）。①汇总敏感度0.95（95%CI:0.92~0.97）,特异度0.89（95%CI:0.86~0.92）,阳性似然比11.09（95%CI:5.73~21.49）,阴性似然比0.07（95%CI:0.05~0.11）,诊断比值比122.01（95%CI:65.08~228.75）,SROC 曲线下面积（AUC）0.977 7,Q*指数0.933。②分别剔除样本量<50文献、中文文献和回顾性研究文献的敏感性分析显示,上述诊断参数的95％CI与原数据有较大重叠。③特异度、阳性似然比的文献间存在显著的异质性,研究地域、PCT检测方法和细菌性脑膜炎诊断标准可能不是异质性产生的原因。④以PCT 5 μg·L-1界值诊断儿童细菌性脑膜炎的敏感度、特异度,SROC AUC和Q*指数最大。结论 PCT在鉴别诊断儿童细菌性脑膜炎与病毒性脑膜炎中有较高的敏感度和特异度,但各研究间存在异质性,使用PCT鉴别诊断儿童细菌性脑膜炎仍需结合具体的临床情况。     

Diagnostic Value of Serum Procalcitonin Level in Differentiating Bacterial from Nonbacterial Meningitis in Children

Objective:

Acute bacterial meningitis in pediatrics remains a serious and potentially lethal disease. Its prognosis is critically dependent on rapid diagnosis and treatment. The use of biological markers, like procalcitonin, has been proposed to facilitate the accuracy of the initial diagnosis of bacterial meningitis. The aim of this study was assessment the diagnostic values of serum procalcitonin (PCT) assay in the diagnosis and differentiation of acute bacterial from non bacterial meningitis.

Methods:

45 patients with suspicion of meningitis were enrolled in the study and were clinically evaluated and investigated by lumbar punctures for cerebrospinal fluid analysis, C-reactive protein and differential leukocyte count. Patients with clinical and laboratory suggestion of bacterial causes were regarded as bacterial meningitis group (29 patients), and those who were suggestive of nonbacterial causes were regarded as nonbacterial group (16 patients).

Findings:

Serum procalcitonin levels were significantly higher in bacterial meningitis group (637±325 pg/ml) compared with non-bacterial meningitis (380±170 pg/ml); P<0.001. Procalcitonin levels were more sensitive and specific (79%, 81%) than C-reactive protein (76%, 75%) and white blood cell count (72%, 75%) in the diagnosis of bacterial meningitis.

Conclusion:

Elevated serum procalcitonin level could be a predictor of bacterial causes of meningitis and is more sensitive and specific than other diagnostic predictors.     

Detection of antigen and antibody in childhood tuberculous meningitis

Objective Mycobacterium tuberculosis excretory secretory 31 kDa, a serine protease antigen (M. tb ES-31), prepared fromMycobacterium tuberculosis H₃₇Ra culture medium has been shown to have potential in detecting tuberculosis. Precise diagnosis and management of tuberculous meningitis, in children in particular, is essential to curtail mortality and morbidity. Methods In this study, M. tb ES-31 antigen, was used in Indirect ELISA to detect tuberculous IgG antibody, in sera and CSF samples while affinity purified anti ES-31 goat antibody was used in sandwich ELISA for detection of tuberculous antigen. In sixty-five samples each of CSF and sera from cases with neurotuberculosis and control with non-tuberculous diseases were collected from Kasturba Hospital, Sevagram. Results Among the 20 patients suffering from neurotuberculosis the IgG antibody was detected in 17(85%) of CSF and 16(80%) of sera samples, while antigen was detected in 18 (90%) in CSF and 16 (80%) in sera. Overall specificity of the assay for both IgG antibody and antigen detection in CSF was 96% while in sera it was 94% for IgG antibody and 96% for antigen detection. Conclusion This study showed the usefulness of mycobacterial serine protease antigen and its antibody in detecting neurotuberculosis.     

Immunogenicity of the whole antigen and glycoprotein I of varicella-zoster virus (VZV) and the VZV skin test antigen

Specific cellular immunity against the whole antigen and glycoprotein I (gp I) of varicella-zoster virus (VZV) and the skin test antigen were determined for 13 healthy immune adults to compare the immunogenicity of these antigens using a lymphoproliferative assay. The stimulation index values (mean ± s.d.) were 16.4 ± 11.2 against the whole VZV antigen, 4.2 ± 2.9 against the VZV skin test antigen and 1.1 ±0.5 against gp I. The immunogenicity of the skin test antigen, which mainly contains gp III and gp IV, appears to be more favorable than that of gp I alone, but to be weaker than that of the whole VZV antigen.     

Comparison of 16S rDNA-PCR Amplification and Culture of Cerebrospinal Fluid for Diagnosis of Bacterial Meningitis

Objective

Early and accurate diagnosis of bacterial meningitis is of critical concern. Optimum and rapid laboratory facilities are not routinely available for detecting the etiologic agents of meningitis. The objective of this study was to compare polymerase chain reaction (PCR) assay with culture for detection of bacteria in central nervous system (CNS) samples from patients suspected to have meningitis.

Methods

One-hundred cerebrospinal fluid (CSF) samples were obtained and divided into two parts. One part of samples was used for standard bacterial culture and gram staining. The remaining was used for DNA extraction. PCR assay was performed with universal primers for 16S rDNA gene of bacteria. Performance characteristics of the test were determined.

Findings

The PCR method was able to detect bacteria in all 36 culture-positive and in 38 of 64 culture-negative cases showing sensitivity and specificity of 100% and 40.6% respectively. Positive predictive value was 48.6% and negative predictive value 100%, however, Kappa coefficient showed the correlation of the 2 methods to be at 0.33.

Conclusion

There are advantages and disadvantages in performance characteristics of the conventional CSF culture and universal CSF 16S rDNA PCR. Therefore, it is recommended to use both methods in clinical practice, particularly in suspicious contaminated samples, with presumable presence of fastidious or slow growing bacteria because of antibiotic consumption.     

Phosphohexose isomerase in cerebrospinal fluid in meningitis

The diagnostic value of determining phosphohexose isomerase (PHI, E.C. 5.3.1.9) activity in the CSF for differential diagnosis of bacterial and viral meningitis was investigated. In 29 patients with untreated bacterial meningitis, a mean enzyme activity of 511 U/l was found, whereas a value 19 U/l was found in 61 cases of viral meningitis. The reference range with an upper limit of 6 U/l was determined from CSF samples from 163 healthy children. The high diagnostic sensitivity and specificity of 100% and 99.5% respectively make PHI a sensitive differential diagnostic parameter in meningitis.     

肺炎链球菌抗原/抗体检测及其在肺炎/脑膜炎病原学诊断中的应用

肺炎是小儿的常见疾病,是导致儿童死亡的主要原因。细菌性脑膜炎是儿童重症感染性疾病,具有发病率高、病死率高、后遗症发生率高等特点。肺炎链球菌(SP)是引起儿童社区获得性肺炎、中耳炎、脓毒症、细菌性脑膜炎等细菌感染性疾病的主要病原菌。明确SP病原是临床合理应用抗生素的前提。细菌分离培养法仍是目前明确SP感染的"金标准",但培养阳性率低,耗时较长,不利于SP快速检测。免疫层析试验、酶联免疫吸附试验、胶乳颗粒凝集试验等免疫学方法具有快速、特异性强、灵敏性较高、操作简便、不受抗菌药物影响等优点,是检测SP感染细菌培养之外的一种补充。     

儿童结核性脑膜炎脑积水Ommaya囊内注药外引流治疗的体会

目的 探讨Ommaya储液囊治疗儿童结核性脑膜炎脑积水的疗效.方法 结核性脑膜炎伴脑积水患儿12例,男9 例,女3例,体重6～38 kg,年龄4个月至12岁.Ⅱ级6例,Ⅲ级4例,Ⅵ级2例.12例均采用储液囊植入,囊内穿刺引流、注药方法治疗.结果 术前脑脊液白细胞数、蛋白含量分别是:(228±139)×106/L、(2.18±1.26) g/L;储液囊内给药2周后白细胞数(21±18)×106/L、蛋白含量(0.69±0.34) g/L.植入12个储液囊,最终取出储液囊8个,长期留置4个,4例再次行V-P分流术.结论 Ommaya储液囊具有操作方便,可随时反复抽取脑脊液检查,避免腰穿;留置时间长,不易感染;经囊内给药起效快等优点.此方法可能更适用于轻中度脑积水且预计短期内脑积水可缓解的患儿.部分患儿可避免长期分流管的植入.