Receiver Operating Research Articles

Theoretical analysis and simulation of a code division multiple access system (CDMA) for secure signal transmission in wideband channels

Theoretical analysis and simulation of a code division multiple access system (CDMA) for secure signal transmission in wideband channels

Evidence of Combining Pharmacophore Modeling-Docking Simulation for Screening on Neuraminidase Inhibitors Activity of Natural Product Compounds

In this study, chemical features of 3D-pharmacophore were built to screen of neuraminidase inhibitors from natural products. The pharmacophore hypothesis selected had five features [one hydrogen bond donor, one negative ionizable (N), one positive ionizable (P) and two hydrophobic moiety (Hy)], also included two excluded volume. The best pharmacophore was created by hypogen in DS 2.5 which has a lowest total cost value (92.055), the highest cost difference (107.807), the lowest RMSD (1.197) and the best correlation coefficient (0.944651). The screening of NADI database natural compounds shows that 167 compounds of 3000 NADI compounds were mapped by using four feature at this screening by optimizing the minimum predicted activity to 0.41. In a docking study, good bonding interaction has been shown by coumarilquinic acid derivatives of NADI compounds mapped against neuraminidase (1FD8B), but only MSC927 has a free energy docking score smaller than DANA-1F8B (-9.56 kcal/mol). We have proved both these methods pharmacophore and docking with the statistic and assay experiment methods. Receiver operating under curve in statistic methods have high value (0.907), whereas MUNANA assay experiment resulted that MSC927 has IC50 smaller than others as mention in silico resulted.

Abstract 18019: Race and Sex Sensitive Stroke Risk Prediction: Analysis of Pooled Data From Atherosclerosis Risk in Communities (ARIC) and Cardiovascular Health Study (CHS) Cohorts

Context: A risk assessment tool predicting increased risk of first stroke helps to identify at-risk individuals and aid in development of intervention strategies leading to the primary prevention of stroke. Most relied-upon Framingham Heart Study (FHS) stroke risk profile (FRS) does not include race due to lack of information on race other than white in FHS. Objective: To develop a race and sex sensitive risk score for incident stroke. Methods: Risk prediction functions were estimated using pooled data from the ARIC and CHS studies on 16,379 participants (55% women, 23% black) with 1,363 (8.3%) incident stroke during 263,295 person-years with median follow-up 18.3 years. Study sample included individual ages 45-84 years and free of stroke and cancer at the initial examination. Study sample did not include stroke events or individuals lost due to other events or follow-up during the first year as well as individuals with missing data on factors of interest. Cox proportional hazards regression analysis was performed after confirming the proportionality of hazards. Akaike (AIC) and Bayesian information criterion (BIC) was used to develop the best fitting model. Results: The risk equation included age, sex, race (non-black/black), left ventricular hypertrophy, peripheral arterial disease, current smoking, prior myocardial infarction, atrial fibrillation (AF), waist to hip ratio, systolic blood pressure (SBP), and diastolic blood pressure, use of antihypertensive therapy (HTNMED), fasting blood sugar and serum creatinine. The risk equation also included interactions between age x race, age x sex, race x AF, and SBP x HTNMED. All predictors included were significantly associated at p <0.05 except for race x AF (p = 0.078). The risk equation demonstrated good discrimination (Harrell’s C = 0.7877) with receiver operator (ROC) curve statistics for 10-year stroke risk of 0.7521 for non-black and 0.7012 for black. The ROC curve statistics for 10-year stroke risk estimated from the FRS were 0.7099 for non-black and 0.6552 for black. Conclusion: This improved stroke risk predictions derived from a large population based data provide race and sex sensitive risk prediction of first stroke based on predictors readily available during routine clinical examination.

Interference versus filtering distortion trade‐offs in OFDM‐based cognitive radios

ABSTRACTCognitive radio (CR) and opportunistic radio access came as a solution for the underutilisation of radio resources. An expected consequence is that the interference management procedures obtain high priority in CR research. While the vast majority of studies focus on interference phenomena towards the licensed primary system (PS), this paper analyses the effects of adjacent primary user (PU) signals to a CR system that uses orthogonal frequency division multiplexing (OFDM) modulation. The lack of orthogonality in OFDM receivers increases out of band interference. The ‘near PU–far CR’ scenario is introduced, an inverse equivalent to the ‘hidden terminal’ problem that may cause serious degradation in the receiver operation. An analytical interference model is developed, and direct filtering of the conventional OFDM waveform is investigated as a means to control interference from PU signals. Closed‐form expressions of the induced distortion are extracted. The results are used to evaluate a filtered‐based OFDM receiver via simulation and to prove that high‐rank filters at CR receivers may be quite beneficial even though OFDM modulation generally avoids their use. Copyright © 2013 John Wiley & Sons, Ltd.

Simulating an in vitro experiment on nanoscale communications by using BiNS2

Nanoscale communications is an emergent research topic with potential applications in many fields. In order to design nanomachines able to exploit the communication potentials of nanoscale environments, it is necessary to identify the basic communication mechanisms and the relevant parameters. In this paper, we show how system parameters can be derived by suitably matching the results of in vitro experiments with those obtained via simulations by using the BiNS2 simulator. In order to scale the simulation from micrometric settings, with timescale in the order of seconds, to real experiments lasting tens of minutes with millimetric size, we enhanced the BiNS2 simulator by introducing a space partition algorithm based on the octree. In this way, the simulator can exploit the high level of parallelism of modern multicore computer architectures. We have used this technique for simulating an experiment focused on the communication between platelets and endothelium through the diffusion of nanoparticles. Simulation results match experimental data, thus allowing us to infer useful information on the receiver operation.

Diagnostic and predict value of procalcitonin in ICU patients diagnosis of sepsis with immune system defect

Objective To evaluate the diagnostic and predict value of procalcitonin (PCT) levels in patients diagnosis of sepsis with immune system defect in the intensive care unit (ICU).Methods This is a retrospective analysis.We enrolled 278 patients diagnosis of sepsis in Emergency ICU,general ICU and Respiratory ICU in Renmin Hospital of Wuhan University from October 2011 to September 2012.Among them,122 patients have normal immune function and 156 patients have auto-immune system diseases or/and requiring corticosteroids or chemotherapy.According to the APACHE Ⅱ score,patients were divided into low-risk group,middle-risk group and high-risk group,and their PCT levels were compared.Logistic regression analysis of the multiple factors was used to screen independent risk factors for predicting 7 days' mortality.The predictive ability was also evaluated and compared between the first time of PCT concentration after admission and dynamic change of PCT within the first week with area under receiver operator's characteristic curve (ROC curve,AUC).Result The results of Spearman correlation analysis showed that there was a significant positive correlation between the patients' PCT concentration and APACHE Ⅱ score (r =0.979,P ＜ 0.05).And there was a positive correlation between the first PCT concentration after admission and 7 days' mortality in-hospital (r =0.826,P ＜ 0.05).Multiple factors logistic regression analysis indicated that both the first time PCT concentration after admission and APACHE Ⅱ score of patients were independent risk factors for predicting 7 days' mortality (PCT OR =1.77,95％ CI =1.28-3.83,P =0.0023).The warning value of 7 days' mortality for patients with normal immune function was PCT≥7.18 ng/ml and for those with abnormal immune function was PCT ≥ 3.52 ng/ml.Compared to dynamic monitoring of PCT,there was no significant difference in sensitivity but specificity is less than the dynamic monitoring of PCT.Conclusions The diagnostic and predict value of procalcitonin (PCT) levels were not affected by the immuno-suppressive therapy.The first time PCT concentration after admission was an independent risk factor for predict of 7 days' mortality in ICU patients with sepsis.The PCT warning value of the sepsis patients with abnormal immune function was much lower compared to those with normal immune function. Key words: Procalcitonin ; Immune function ; Sepsis ; ICU ; Prognosis ; Retrospective analysis ; Independent risk factor; APACHE Ⅱ score

Design of a Reconfigurable Platform for Navigation Signal Simulation

Navigation signal simulator can generate signals consistent with real GNSS (Global Navigation Satellite System) signals, which can be processed by GNSS receivers in the same manner as it processes satellite signals in a real testing environment. The simulator can offer a high-fidelity means of testing GNSS receivers and other related systems. Such tests can be carried out in laboratories due to control of the GNSS constellation and global atmospheric environment by a single device. The navigation signal simulator, which can provide a real-like environment for the research and testing of navigation receivers, has been the key instrument for developing navigation systems and receiving devices, particularly for high-dynamic receivers. Therefore it has increasingly received widespread attentions in military and industrial sectors. With the development of a variety of new navigation systems and signal standards, there is a higher demand for the compatibility and renewal speed of the navigation signal simulators; specifically, it should be multi-mode and reconfigurable in order to realize the flexible design of navigation systems. Although a lot of GNSS simulators have been developed and used, the reconfigurable technologies have not yet appeared in the literature and applied to practices. This means that the existing simulators cannot achieve simulation of multiple GNSS signals by reconfiguration of the software and hardware on the same platform. In this paper, a new reconfigurable platform for navigation signal simulation is proposed and studied, aiming to simulate multi-mode and multi-frequency navigation signals. The performance of the proposed platform is validated from three perspectives: mathematic simulation software, output signals and receiver operation. The result shows that the platform can generate multi-mode and multi-frequency navigation signals through reconfiguration of the software and hardware on the same platform, hence supporting design of a number of navigation systems including Beidou, Global Positioning System (GPS), Russian Global Navigation Satellite System (GLONASS) and European Galileo system. The GNS8000 series navigation satellite signal simulator, designed based on such platform, have been successfully applied to the Beidou navigation satellite systems and widely used in the related fields of research and industries.

Evaluation of the Charlson Comorbidity Index to Predict Early Mortality in Implantable Cardioverter Defibrillator Patients

Current guidelines consider the implantation of an implantable cardioverter defibrillator (ICD) a class III indication in patients with a life expectancy of <1 year. An evaluation of concomitant noncardiac conditions may identify patients whom may not derive benefit with ICD therapy. We sought to evaluate the association of the Charlson comorbidity index (CCI) on the prediction of early mortality (EM), death <1 year after ICD implant. The study population consisted of patients (n = 1062) undergoing ICD implantation for the primary or secondary prevention of sudden cardiac death from 1997 to 2007. The predictive value of the CCI on the risk of EM and appropriate shock therapy for ventricular arrhythmias as compared to patients without EM after ICD implant was calculated using multivariable Cox proportional hazards and receiver operator analyses. Patients experiencing EM (n = 110) demonstrated higher CCI scores (mean 2.8 ± 1.3 vs 1.5 ± 1.2, P < 0.001) as compared to individuals without EM (n = 963). Among patients with a CCI of 0, 1, 2, 3, 4, and ≥5, the incidence of EM increased from 5% to 78%. The CCI was an independent predictor of EM (AHR 1.4 [95% CI 1.2-1.6], P < 0.001, per single score increase). Patients who experienced EM demonstrated a decreased incidence of appropriate ICD therapy when compared to patients without EM (AHR 0.4 [95% CI 0.2-0.7], P = 0.001). Noncardiac conditions are commonly observed among patients undergoing ICD implantation. Guidelines must incorporate a comprehensive assessment of concomitant comorbidities to minimize the risk of EM and to maximize the survival benefit with ICD therapy.

Circulating Angiogenic Modulatory Factors Predict Survival and Functional Class in Pulmonary Arterial Hypertension

The diagnosis of pulmonary arterial hypertension (PAH) is frequently delayed. We hypothesized that circulating angiogenic modulatory protein levels might correspond with vascular remodeling activity and serve as sensitive biomarkers of PAH. Levels of soluble endoglin (sEng), soluble vascular endothelial growth factor receptor-1 (sVEGFR1), N-terminal brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP), and other biomarkers were measured in peripheral blood from 97 PAH patients, 16 first-degree relatives of idiopathic or heritable pulmonary arterial hypertension (HPAH) patients, and 56 controls, and correlated with disease, functional class, hemodynamic parameters, exercise capacity, and transplant-free survival. Endoglin expression was analyzed in lung tissues of six individuals with idiopathic or HPAH and four individuals without PAH. Levels of sEng, sVEGFR1, CRP, and NT-proBNP were elevated in Group I PAH of diverse etiologies, with sEng performing better than NT-proBNP in detecting PAH (receiver operator characteristic-area-under-the curve [ROC-AUC] of 0.82 ± 0.03 vs. 0.71 ± 0.05, P = 0.016). While sEng, sVEGFR1, and NT-proBNP correlated with New York Heart Association (NYHA) class, sEng levels were more sensitive than NT-proBNP in detecting NYHA Class I-II disease (ROC-AUC of 0.88 ± 0.05 vs. 0.67 ± 0.08, P = 0.028). sEng, sVEGFR1, CRP, and NT-proBNP predicted transplant-free survival by univariate Cox regression. After adjusting for NT-proBNP levels, each of the other three markers predicted transplant-free survival. In multivariate analysis, sEng and CRP were independent predictors of survival. Endoglin expression was markedly enhanced in the microvascular endothelium and endovascular lesions of PAH versus control lung tissues. Circulating angiogenic proteins sEng and sVEGFR1 are sensitive markers of prognosis and function in Group I PAH, including mildly symptomatic disease, and may provide unique noninvasive data reflecting underlying remodeling activity.

Endoscopic diagnosis of gastric intestinal metaplasia: A prospective multicenter study

Intestinal metaplasia (IM) of the gastric mucosa has long attracted attention as a premalignant lesion involved in gastric carcinogenesis. However, endoscopic diagnosis of IM has remained unclear for a long time. In recent years, the methylene blue staining technique and narrow-band imaging (NBI) magnifying endoscopy have facilitated clinical diagnosis of IM, although these methods have some problems due to their complexity. Simple methods for diagnosis of IM using conventional endoscopy and the indigo carmine contrast (IC) method are necessary. This study was a multicenter, prospective, randomized, comparative study involving 10 facilities. The appearance of IM was examined using conventional and IC methods with an electronic endoscope. Subjects included 163 patients, of whom 87 and 76 underwent conventional and IC methods, respectively. Sensitivity, specificity, and receiver operating characteristic/area under thecurve (ROC/AUC) of conventional and IC methods for the detection of IM in the gastric antrum showed that diagnostic performance of the conventional method was higher, but not significantly, than that of the IC method. Sensitivity, specificity and ROC/AUC of conventional and IC methods for the detection of IM in the gastric body showed that the IC method yielded better (but not significantly better) results than the conventional method. The diagnostic performance of the conventional method did not significantly differ from that of the IC method. A villous appearance, whitish mucosa, and rough mucosal surface, as observed by both methods, and areae gastricae pattern, as observed by the IC method, were useful indicators for endoscopic diagnosis of IM.

Modelling of the receiver transient flux distribution due to cloud passages on a solar tower thermal power plant

As more and more solar tower thermal power plants are being operated, built or planned, effort is put both on the development and research to bring costs down and increase the plant efficiency. In those plants, the central receiver is one of the key components, accounting for a large investment share. Receivers have to sustain strong thermal stresses caused by irradiation transients, mainly due to cloud passages. To avoid premature failures, increase the receiver cyclic life, and allow longer daily operation periods, an anticipation of the most likely or the worst situations is required. First the calculation of the receiver incident flux distribution is performed, second the cloud and cloud passage characteristics are identified for a given location, third the most likely case is simulated by covering and uncovering the heliostat field, then a worst case configuration is presented, and finally a strategy for the start-up/shut-down of the heliostats is proposed. The value of terms such as the heat flux peak, the maximal flux gradient, the fastest flux transient and total power transients are needed to choose the control strategies regarding heliostat orientation and the receiver operation, as well as the elimination of some bad plant layouts during the design phase.

Performance Evaluation of a Low-Complexity Receiver Concept for TOA-Based Ultrawideband Ranging

In this paper, a novel low-complexity time-of-arrival (TOA) estimation strategy and a conceptual receiver setup for ultrawideband (UWB) signals is proposed, and its performance is evaluated. The receiver consists of an analog peak detector followed by two RC filters with different time constants. From two exponentially decaying signals, the TOA of the first peak of the received signal is reconstructed. This solution requires simple signal processing and sampling rates on the order of only a few tens of megahertz. At the same time, the achieved range error is at centimeter level since the large signal bandwidth used is fully exploited. To allow for performance flexibility, a statistical framework is proposed in which results of multiple initial TOA estimates are combined into a final estimate. Impairments due to narrowband interference are investigated, and a coarse acquisition scheme based on maximum energy detection is described. This last step is required for proper operation of the TOA receiver. A link budget analysis, which is based on the FCC power limitations for UWB signals, shows that reliable ranging is feasible up to 300 m in line-of-sight situations and up to 60 m in non-line-of-sight cases. The presented solution avoids the main technological challenges, namely extremely high sampling rates and complex processing at the receiver, which currently limit practical implementations of high-precision UWB positioning systems.

A 40-Gb/s Optical Transceiver Front-End in 45 nm SOI CMOS

A low-power, 40-Gb/s optical transceiver front-end is demonstrated in a 45-nm silicon-on-insulator (SOI) CMOS process. Both single-ended and differential optical modulators are demonstrated with floating-body transistors to reach output swings of more than 2 VPP and 4 VPP, respectively. A single-ended gain of 7.6 dB is measured over 33 GHz. The optical receiver consists of a transimpedance amplifier (TIA) and post-amplifier with 55 dB ·Ω of transimpedance over 30 GHz. The group-delay variation is ±3.9 ps over the 3-dB bandwidth and the average input-referred noise density is 20.5 pA/(√Hz) . The TIA consumes 9 mW from a 1-V supply for a transimpedance figure of merit of 1875 Ω /pJ. This represents the lowest power consumption for a transmitter and receiver operating at 40 Gb/s in a CMOS process.

The timing of exploratory decision-making revealed by single-trial topographic EEGanalyses

Decision-making in an uncertain environment is driven by two major needs: exploring the environment to gather information or exploiting acquired knowledge to maximize reward. The neural processes underlying exploratory decision-making have been mainly studied by means of functional magnetic resonance imaging, overlooking any information about the time when decisions are made. Here, we carried out an electroencephalography (EEG) experiment, in order to detect the time when the brain generators responsible for these decisions have been sufficiently activated to lead to the next decision. Our analyses, based on a classification scheme, extract time-unlocked voltage topographies during reward presentation and use them to predict the type of decisions made on the subsequent trial. Classification accuracy, measured as the area under the Receiver Operator's Characteristic curve was on average 0.65 across 7 subjects. Classification accuracy was above chance levels already after 516ms on average, across subjects. We speculate that decisions were already made before this critical period, as confirmed by a positive correlation with reaction times across subjects. On an individual subject basis, distributed source estimations were performed on the extracted topographies to statistically evaluate the neural correlates of decision-making. For trials leading to exploration, there was significantly higher activity in dorsolateral prefrontal cortex and the right supramarginal gyrus; areas responsible for modulating behavior under risk and deduction. No area was more active during exploitation. We show for the first time the temporal evolution of differential patterns of brain activation in an exploratory decision-making task on a single-trial basis.

Methods for Processing and Interpretation of AIS Signals Corrupted by Noise and Packet Collisions

Methods for Processing and Interpretation of AIS Signals Corrupted by Noise and Packet Collisions The authors deal with the operation of Automatic Identification System (AIS) used in the marine traffic monitoring to broadcast messages containing information about the vessel: id, payload, size, speed, destination etc., meant primarily for avoidance of ship collisions. To extend the radius of AIS operation, it is envisaged to dispose its receivers on satellites. However, in space, due to a large coverage area, interfering factors are especially pronounced - such as packet collision, Doppler's shift and noise impact on AIS message receiving, pre-processing and decoding. To assess the quality of an AIS receiver's operation, a test was carried out in which, varying automatically frequency, amplitude, noise, and other parameters, the data on the ability of the receiver's ability to decode AIS signals are collected. In the work, both hardware- and software-based AIS decoders were tested. As a result, quite satisfactory statistics has been gathered - both on the common and the differing features of such decoders when operating in space. To obtain reliable data on the software-defined radio AIS receivers, further research is envisaged.

Fiber optical CATV transport systems based on PM and light injection-locked DFB LD as a duplex transceiver

A bidirectional fiber optical CATV transport system employing phase modulation (PM) scheme and frequency up-conversion technique to deal with downstream CATV signals, and using light injection-locked distributed feedback laser diode (DFB LD) as a duplex transceiver at the receiving site is proposed and experimentally demonstrated. With optimum injection wavelength and power level, a DFB LD is efficiently employed for both the transmitter and receiver operations. Such DFB LD is used to replace the functions of delay interferometer (DI) and CATV receiver, and also to be as the upstream light source. To the best of our knowledge, it is the first time to successfully utilize a DFB LD to detect the phase-modulated CATV signals. Impressive experimental results prove that our proposed systems not only can employ the PM scheme and the frequency up-conversion technique to optimize the overall performances of systems, but also can use an injection-locked DFB LD to detect the downstream phase-modulated CATV signals as well as to transmit the upstream CATV ones simultaneously.

Is HbA 1c a good screening test for diabetes mellitus?

Objectives HbA 1c has been recently recommended as the primary diagnostic test for diabetes. This study evaluated the positive predictive value (PPV) and negative predictive value (NPV) of HbA 1c against the oral glucose tolerance test (OGTT) in three locations. Design and methods Three years of data with concurrent OGTT and HbA 1c tests were extracted from Laboratory Information Systems (LIS) and receiver operator (ROC) curves and positive and negative predictive values calculated comparing the OGTT with the HbA 1c values using a 10% prevalence of diabetes. Results The recommended threshold HbA 1c value of 6.5% did not give the optimal combination of NPV (0.93 to 0.92) and PPV (0.40 to 0.61) compared to a threshold HbA 1c value of 7.0% (NPV 0.91 to 0.92, PPV 0.61 to 0.73). Conclusion The optimal HbA 1c value for the diagnosis of diabetes is 7.0% but even at this HbA 1c the PPV is suboptimal and may cause up to 12% of patients without diabetes, as defined by a normal OGTT, to be classified having diabetes mellitus.

2$\,\times\,$2 Switch Matrix for WiMAX Relay Station Applications

A 2 × 2 Switch Matrix operating at the 3.3-3.8 GHz frequency band is presented. The design is based on PIN diode switch elements. The achieved isolation is below 80 dB, while the insertion loss is less than 2 dB for the full frequency band. The proposed 2 × 2 Switch Matrix is used as the antenna switching element in the RF Front-End of a WiMAX Relay Station, supporting both Time-domain Transmit and Receive and Simultaneous Transmit and Receive operation in Time Division Duplexing mode.

Late pregnancy associated plasma protein A levels decrease in preterm labor

Objective. The purpose of the present study is to evaluate late, ‘at admission’, Pregnancy-associated plasma protein-A (PAPP-A) levels as a predictor of preterm birth in women with complaints of preterm labor or preterm painful contractions.Methods. Prospective cohort study of singleton gestations, 23–37 weeks, and symptoms of preterm labor. Primary end point was delivery < 37 weeks. Predictive PAPP-A values were calculated both for preterm delivery and threatened preterm delivery on receiver operator curve.Results. In all, 41 women (38.3%) delivered before 37 weeks (Group 1); 32 women (30.7%) had symptoms of preterm labor but did not deliver preterm (Group 2); 31 women (29.7%) delivered term (Group 3, control). Mean PAPP-A levels in preterm-labor and its matched control were 33.4 ± 19.9 and 52.5 ± 25.4 mIU/ml, respectively, and difference was statistically significant (p = 0.003). Mean PAPP-A level in threatened preterm labor group was 47.6 ± 25.3 mIU/ml and difference was significant compared to preterm-labor, but not significant compared to control group (p = 0.028 and p = 0.74, respectively).Conclusion. Late PAPP-A levels decreased in preterm labor, levels < 29.8 mIU/ml was associated with increased risk for preterm birth, supporting active management whereas cutoff value of 33.6 mIU/ml is useful for discrimination of preterm birth from threatened preterm birth reaching to term.

IL-6 and IL-8 in cerebrospinal fluid from patients with aseptic meningitis and bacterial meningitis: their potential role as a marker for differential diagnosis

Cytokines are molecules that act as mediators of immune response; cerebral spinal fluid (CSF) IL-6 is found in all meningeal inflammatory diseases, but IL-8 is associated with acute bacterial meningitis (ABM). A case control study was done to ascertain the discriminatory power of these cytokines in differentiating ABM from aseptic meningitis (AM); IL-6 and IL-8 CSF concentrations were tested through ELISA in samples collected from patients who underwent investigation for meningitis. Sixty patients, 18 with AM, nine with bacteriologic confirmed ABM and 33 controls, assisted in 2005 (MA and controls) and 2007 (ABM) were included. Differently from controls, IL-6 concentrations were increased both in MA and ABM patients (p < 0.05). CSF IL-8 levels were higher in ABM than in AM and controls (p < 0.05). Discriminatory power in ABM as assessed by the area under receiver operator (ROC) curve was 0.951 for IL-8, using a cut-off of 1.685 ng/dL (100% of sensitivity and 94% of specificity). The CSF concentration of both IL-6 and IL-8 are increased in the presence of meningeal inflammation, IL-8 could be an important tool to differentiate ABM from AM.