Pathogen Detection Using Frequency Domain Fluorescent Lifetime Measurements

OBJECTIVE

Inflammation of the meninges is a source of severe morbidity and therefore is an important health concerns worldwide. The conventional clinical microbiology approaches used today to identify pathogens suffer from several drawbacks and frequently provide false results. This research describes a fast method to detect the presence of pathogens using the frequency domain (FD) fluorescence lifetime (FLT) imaging microscopy (FLIM) system.

METHODS

The study included 43 individuals divided into 4 groups: 9 diagnosed with different types of bacteria; 16 diagnosed with different types of viruses; 5 healthy samples served as a control; and 12 samples were negative to any pathogen, although presenting related symptoms. All samples contained leukocytes that were extracted from the cerebrospinal fluid (CSF) and were subjected to nuclear staining by 4', 6-diamidino-2-phenylindole (DAPI) and FLT analyses based on phase and amplitude crossing point (CRPO).

RESULTS

Using notched boxplots, we found differences in 95% probability between the first three groups through different notch ranges (NR). Pathogen samples presented a longer median FLT (3.28 ns with NR of 3.24-3.32 ns in bacteria and 3.18 ns with NR of 3.16-3.21 ns in viruses) compared to the control median FLT (2.65 ns with NR of 2.63-2.67 ns). Furthermore, we found that the undetected forth group was divided into two types: a relatively normal median FLT (2.72 ns with NR of 2.68-2.76 ns) and a prolonged FLT (3.22 ns with NR of 3.17-3.27 ns).

CONCLUSION

FLT measurements can differentiate between control and pathogen by the CRPO method.

SIGNIFICANCE

The FD-FLIM system can provide a high throughput diagnostic technique that does not require a physician.

Meningoencephaloradiculitis following infection with tick borne encephalitis virus: case report and review of the literature

Tick borne encephalitis (TBE) is an infectious zoonotic disease caused by an RNA virus that is endemic to Central and Eastern Europe, Russia, and large parts of Asia. The tick borne encephalitis virus (TBEV) is transmitted through the saliva of infected ticks and infected goat milk. In the vast majority of cases, an infection with TBEV has a subclinical course. However, in some cases, it leads to neurological symptoms due to meningitis, meningoencephalitis, meningoencephalomyelitis, or meningoencephaloradiculitis. Here, we present the first case of meningoencephaloradiculitis in Belgium.

Management of acute meningitis

Acute meningitis remains a devastating disease. Clinicians need a low threshold for suspecting meningitis, to undertake appropriate investigations and provide treatment in a timely manner, to minimise the risk of poor outcome in bacterial disease, while limiting unnecessary treatment in viral meningitis.

Meningitis Associated with Simultaneous Infection by Multiple Dengue Virus Serotypes in Children, Brazil

To determine the causes of viral meningitis, we analyzed 22 cerebrospinal fluid samples collected during the 2014–2015 dengue epidemics in Brazil. We identified 3 serotypes of dengue virus (DENV-1, -2, and -3), as well as co-infection with 2 or 3 serotypes. We also detected the Asian II genotype of DENV-2.

[Chronic post-dural headache secondary to meningitis]

In this case report a young man was admitted with fever and headache, and a lumbar puncture revealed viral meningitis. After discharge, the patient experienced persistent headache, which worsened, when he was in upright position. The condition was considered secondary to the meningitis. After 14 months, the patient was diagnosed with post-dural puncture headache and treated with an epidural blood patch (EBP). The patient experienced no headache for three months, whereafter it returned. Subsequent EBP's were unsuccessful. This case emphasizes the importance of paying attention to orthostatic components in headaches.

Use of Testing for West Nile Virus and Other Arboviruses

In the United States, the most commonly diagnosed arboviral disease is West Nile virus (WNV) infection. Diagnosis is made by detecting WNV IgG or viral genomic sequences in serum or cerebrospinal fluid. To determine frequency of this testing in WNV-endemic areas, we examined the proportion of tests ordered for patients with meningitis and encephalitis at 9 hospitals in Houston, Texas, USA. We identified 751 patients (567 adults, 184 children), among whom 390 (52%) experienced illness onset during WNV season (June-October). WNV testing was ordered for 281 (37%) of the 751; results indicated acute infection for 32 (11%). Characteristics associated with WNV testing were acute focal neurologic deficits; older age; magnetic resonance imaging; empirically prescribed antiviral therapy; worse clinical outcomes: and concomitant testing for mycobacterial, fungal, or other viral infections. Testing for WNV is underutilized, and testing of patients with more severe disease raises the possibility of diagnostic bias in epidemiologic studies.

Community-Acquired Meningitis in HIV-Infected Patients in the United States

We conducted a retrospective study of 549 adults admitted with community-acquired meningitis (CAM) to several hospitals in New Orleans, LA and Houston, TX between 1999 and 2014 to characterize the current epidemiology, clinical manifestations, cerebrospinal fluid (CSF) characteristics, and outcomes of CAM between HIV-infected and uninfected patients and to identify risk factors for adverse outcomes in CAM. Bivariate analysis and logistic regression analysis were used to identify prognostic factors. A total of 1022 patients with CAM were screened. Only 549 (53.7%) subjects had an HIV test and were included in the study. Of those, 138 (25%) had HIV infection. HIV-infected patients presented with less meningeal symptoms (headache, neck stiffness, and Kernig sign), but with higher rates of hypoglycorrhachia, elevated CSF protein, and an abnormal cranial imaging (p < 0.05). More than 50% of all the patients had an unknown etiology. Cryptococcal meningitis was the most common identified etiology of CAM in HIV-infected patients followed by neurosyphilis and varicella-zoster virus (VZV). Viral and bacterial etiologies were the most frequent etiologies in non-HIV-infected patients. Streptococcus pneumoniae was the most common bacterial pathogen in both groups, but it was rare overall (2%). Adverse clinical outcomes were similar in both groups (27% vs. 24%). Logistic regression identified hypoglycorrhachia and an abnormal neurological examination as independent predictor factors of worse outcome in all patients with meningitis. Our results demonstrate that the etiology, clinical presentation, and CSF findings differ between HIV-infected and HIV-uninfected adults with CAM, but clinical outcomes are similar.

Application value of procalcitonin in patients with central nervous system infection

OBJECTIVE

To study the application value of procalcitonin (PCT) in patients with central nervous system (CNS) infection.

PATIENTS AND METHODS

A total of 66 patients, including 24 patients with suppurative meningitis, 20 patients with viral meningitis and 22 patients with tuberculous meningitis, were enrolled. 20 patients admitted to the hospital due to epilepsy or headache without infection in the same period were enrolled as the control group. PCT, high-sensitivity C-reactive protein (Hs-CRP), high-sensitivity C-reactive protein (Hs-CRP), protein quantification, chloride and glucose in serum and cerebrospinal fluid, were collected.

RESULTS

The serum PCT level in suppurative meningitis group was significantly higher than that in other three groups. The dynamic monitoring of suppurative meningitis group on admission, at 72 h and 1 week after treatment showed that the serum PCT level was significantly decreased. PCT levels in cerebrospinal fluid in suppurative meningitis group, viral meningitis group and tuberculous meningitis group were decreased successively, and the differences were statistically significant. The detection of PCT in cerebrospinal fluid was more valuable than serum PCT detection in distinguishing tuberculous meningitis from viral meningitis. Continuous monitoring of changes in PCT in cerebrospinal fluid showed that there was no statistically significant difference before and after treatment. PCT level in cerebrospinal fluid was positively correlated with the serum PCT, cerebrospinal fluid white blood cell (WBC), and protein content in cerebrospinal fluid.

CONCLUSIONS

The dynamic changes of serum PCT in patients with suppurative meningitis can be used to evaluate the disease, guide the clinical medication, and monitor the prognosis.

[Clinical, epidemiological and etiological studies of adult aseptic meningitis: Report of 11 cases with varicella zoster virus meningitis]

We treated 11 cases (52.7 ± 14.9 years, all male) with varicella zoster virus (VZV) meningitis and 437 cases with adult aseptic meningitis from 2004 to 2016. The incidence rate of adult VZV meningitis in the cases with aseptic meningitis was 2.5%. Herpes zoster infections are reported to have occurred frequently in summer and autumn. VZV meningitis also occurred frequently in the similar seasons, in our patients. The diagnoses were confirmed in 9 cases with positive VZV-DNA in the cerebrospinal fluid and in 2 cases with high VZV-IgG indexes (> 2.0). For diagnosis confirmation, the former test was useful for cases within a week of disease onset, and the latter index was useful for cases after a week of disease onset. Zoster preceded the meningitis in 8 cases, while the meningitis preceded zoster in 1 case, and 2 cases did not have zoster (zoster sine herpete). Two patients were carriers of the hepatitis B virus, 1 patient was administered an influenza vaccine 4 days before the onset of meningitis, and 1 patient was orally administered prednisolone for 2 years, for treatment. Their immunological activities might have been suppressed. The neurological complications included trigeminal neuralgia, facial palsy (Ramsay Hunt syndrome), glossopharyngeal neuralgia, and Elsberg syndrome. Because the diseases in some patients can become severe, they require careful treatment.

Diagnostic value of lactate, procalcitonin, ferritin, serum-C-reactive protein, and other biomarkers in bacterial and viral meningitis: A cross-sectional study

There are many difficulties distinguishing bacterial from viral meningitis that could be reasonably solved using biomarkers. The aim of this study was to evaluate lactate, procalcitonin (PCT), ferritin, serum-CRP (C-reactive protein), and other known biomarkers in differentiating bacterial meningitis from viral meningitis in children.All children aged 28 days to 14 years with suspected meningitis who were admitted to Mofid Children's Hospital, Tehran, between October 2012 and November 2013, were enrolled in this prospective cross-sectional study. Children were divided into 2 groups of bacterial and viral meningitis, based on the results of cerebrospinal fluid (CSF) culture, polymerase chain reaction, and cytochemical profile. Diagnostic values of CSF parameters (ferritin, PCT, absolute neutrophil count [ANC], white blood cell count, and lactate) and serum parameters (PCT, ferritin, CRP, and erythrocyte sedimentation rate [ESR]) were evaluated.Among 50 patients with meningitis, 12 were diagnosed with bacterial meningitis. Concentrations of all markers were significantly different between bacterial and viral meningitis, except for serum (P = .389) and CSF (P = .136) PCT. The best rates of area under the receiver operating characteristic (ROC) curve (AUC) were achieved by lactate (AUC = 0.923) and serum-CRP (AUC = 0.889). The best negative predictive values (NPV) for bacterial meningitis were attained by ANC (100%) and lactate (97.1%).The results of our study suggest that ferritin and PCT are not strong predictive biomarkers. A combination of low CSF lactate, ANC, ESR, and serum-CRP could reasonably rule out the bacterial meningitis.

With a little help from a computer: discriminating between bacterial and viral meningitis based on dominance-based rough set approach analysis

Differential Diagnosis of bacterial and viral meningitis remains an important clinical problem. A number of methods to assist in the diagnoses of meningitis have been developed, but none of them have been found to have high specificity with 100% sensitivity.We conducted a retrospective analysis of the medical records of 148 children hospitalized in St. Joseph Children's Hospital in Poznań. In this study, we applied for the first time the original methodology of dominance-based rough set approach (DRSA) to diagnostic patterns of meningitis data and represented them by decision rules useful in discriminating between bacterial and viral meningitis. The induction algorithm is called VC-DomLEM; it has been implemented as software package called jMAF (http://www.cs.put.poznan.pl/jblaszczynski/Site/jRS.html), based on java Rough Set (jRS) library.In the studied group, there were 148 patients (78 boys and 70 girls), and the mean age was 85 months. We analyzed 14 attributes, of which only 4 were used to generate the 6 rules, with C-reactive protein (CRP) being the most valuable.Factors associated with bacterial meningitis were: CRP level ≥86 mg/L, number of leukocytes in cerebrospinal fluid (CSF) ≥4481 μL, symptoms duration no longer than 2 days, or age less than 1 month. Factors associated with viral meningitis were CRP level not higher than 19 mg/L, or CRP level not higher than 84 mg/L in a patient older than 11 months with no more than 1100 μL leukocytes in CSF.We established the minimum set of attributes significant for classification of patients with meningitis. This is new set of rules, which, although intuitively anticipated by some clinicians, has not been formally demonstrated until now.

Diagnostic accuracy of two multiplex real-time polymerase chain reaction assays for the diagnosis of meningitis in children in a resource-limited setting

INTRODUCTION

Accurate etiological diagnosis of meningitis is important, but difficult in resource-limited settings due to prior administration of antibiotics and lack of viral diagnostics. We aimed to develop and validate 2 real-time multiplex PCR (RT-PCR) assays for the detection of common causes of community-acquired bacterial and viral meningitis in South African children.

METHODS

We developed 2 multiplex RT- PCRs for detection of S. pneumoniae, N. meningitidis, H. influenzae, enteroviruses, mumps virus and herpes simplex virus. We tested residual CSF samples from children presenting to a local paediatric hospital over a one-year period, whose CSF showed an abnormal cell count. Results were compared with routine diagnostic tests and the final discharge diagnosis. We calculated accuracy of the bacterial RT-PCR assay compared to CSF culture and using World Health Organisation definitions of laboratory-confirmed bacterial meningitis.

RESULTS

From 292 samples, bacterial DNA was detected in 12 (4.1%) and viral nucleic acids in 94 (32%). Compared to CSF culture, the sensitivity and specificity of the bacterial RT-PCR was 100% and 97.2% with complete agreement in organism identification. None of the cases positive by viral RT-PCR had a bacterial cause confirmed on CSF culture. Only 9/90 (10%) of patients diagnosed clinically as bacterial meningitis or partially treated bacterial meningitis tested positive with the bacterial RT-PCR.

DISCUSSION

In this population the use of 2 multiplex RT-PCRs targeting 6 common pathogens gave promising results. If introduced into routine diagnostic testing, these multiplex RT-PCR assays would supplement other diagnostic tests, and have the potential to limit unnecessary antibiotic therapy and hospitalisation.

Age-specific application of neutrophil-to-lymphocyte ratio in meningitis: a nationwide study

Cerebrospinal fluid (CSF) neutrophil counts and neutrophil-to-lymphocyte ratio (NLR) are useful in distinguishing bacterial and viral meningitis. Given that meningitis is clinically heterogeneous with regard to age, here we investigated the validity of the CSF NLR and neutrophil assay according to age group. Data from the nationwide referral of >4,000 meningitis cases to the Hellenic Meningitis Reference Laboratory between 2006 and 2013 were examined. CSF NLR and neutrophil counts were stratified according to age, and assay performance was determined using previous cut-off values of 2 and 287 cells/μl for CSF NLR and neutrophils respectively. The distribution of bacterial versus viral meningitis was heterogenous across age groups, with a low proportion of bacterial meningitis in patients aged 5-14. CSF neutrophil count and NLR were significantly more discriminatory for bacterial meningitis in patients aged over 14 years than those aged 0-14. The odds ratio (OR), sensitivity, specificity and positive predictive value (PPV) were significantly higher in older patients for both biomarkers. When combined, the false-positive and false-negative detection of bacterial meningitis was 3.9 and 8.5% respectively, and the OR of 262.2 was 2.5-fold greater than expected from a multiplicative effect alone in patients aged >14 years. Care is required when applying diagnostic tests for meningitis in different age groups because of patient heterogeneity. This is the first description of the age distribution of meningitis cases in Greece, and knowledge of the age-related distribution of neutrophils and NLR in meningitis cases could help towards developing age-specific meningitis diagnostic assays.

The Successful Treatment of a Cord Blood Transplant Recipient with Varicella Zoster Virus Meningitis, Radiculitis and Myelitis with Foscarnet

Infections of the central nervous system (CNS) with varicella zoster virus (VZV) is a rare occurrence after allogeneic hematopoietic stem cell transplantation. We herein report a case of VZV meningitis, radiculitis and myelitis that developed 8 months after cord blood transplantation, shortly after the cessation of cyclosporine and low-dose acyclovir. Although treatment with acyclovir did not achieve a satisfactory response, the patient was successfully treated with foscarnet. Our report indicates that VZV infection should be considered in allo-hematopoietic stem cell transplantation (HSCT) patients with CNS symptoms and that foscarnet may be effective for the treatment of acyclovir-resistant VZV infections of the CNS. The development of optimal prophylactic strategies and vaccination schedules may eradicate post-transplant VZV disease.

Astrovirus MLB2, a New Gastroenteric Virus Associated with Meningitis and Disseminated Infection

This virus is an unrecognized cause of central nervous system infection, particularly among immunocompromised patients.

Next-generation sequencing has identified novel astroviruses for which a pathogenic role is not clearly defined. We identified astrovirus MLB2 infection in an immunocompetent case-patient and an immunocompromised patient who experienced diverse clinical manifestations, notably, meningitis and disseminated infection. The initial case-patient was identified by next-generation sequencing, which revealed astrovirus MLB2 RNA in cerebrospinal fluid, plasma, urine, and anal swab specimens. We then used specific real-time reverse transcription PCR to screen 943 fecal and 424 cerebrospinal fluid samples from hospitalized patients and identified a second case of meningitis, with positive results for the agent in the patient’s feces and plasma. This screening revealed 5 additional positive fecal samples: 1 from an infant with acute diarrhea and 4 from children who had received transplants. Our findings demonstrate that astrovirus MLB2, which is highly prevalent in feces, can disseminate outside the digestive tract and is an unrecognized cause of central nervous system infection.

[Evaluation of an Xpert EV (Cepheid®) molecular diagnostic technique for enteroviral meningitis]

INTRODUCTION

Polymerase chain reaction (PCR) assays have shown to be useful and quick for the diagnosis of enterovirus in aseptic meningitis. The aim of our study was to analyse the changes in clinical practice after the introduction of a real-time polymerase chain reaction (RT-PCR) technique using the Xpert EV (Cepheid^®) assay for the qualitative detection of enterovirus RNA in cerebrospinal fluid specimens from children with suspected viral meningitis.

METHODS

A retrospective study was performed in children older than 1year, diagnosed with enterovirus meningitis in a third level hospital from November 2006 to February 2013. The first period, before the availability of Xpert EV (Cepheid^®) (Group1, November 2006-August 2010) was compared with the later period (Group2, September 2010-February 2013). Clinical characteristics, the mean length of stay, and the cost per inpatient cases, were compared between the 2periods.

RESULTS

Forty-one patients (60.9% male) were included, with a median age of 64 months (interquartile range 28-96). Twenty-six patients (63.4%) were included in Group2. There were non-statistically significant differences in the epidemiological, disease severity, and laboratory characteristics between both periods of study. A significant difference was observed in the mean length of stay, with it being shorter in Group2 (48hours vs 40.5hours, P=.039), and a significant lower inpatient cost per case (€779.77 vs €656.05, P<.05).

CONCLUSION

Xpert EV (Cepheid^®) assay was useful for decreasing the length of hospital stay and the costs associated with hospitalisation in children with enterovirus meningitis.

Three cases of mumps virus and enterovirus coinfection in children with enteroviral meningitis

Several viruses are responsible for aseptic meningitis; however, in the region of Southwest Iran, the role played by each virus is still not very well known. The aim of this study is to determine the relative frequencies of mumps virus, herpes viruses, and enteroviruses, as well as coinfections among them, in patients with aseptic meningitis.In this cross-sectional study, samples of cerebrospinal fluid were collected between December 2012 and December 2013 from patients under 14 years, who were hospitalized in Abuzar Children's Hospital in Ahvaz, Southwest Iran (the only children's hospital in Khuzestan province and Southwest Iran).All 66 cerebrospinal fluid samples and corresponding clinical data were collected from patients with aseptic meningitis by specialists, and with the patients' consent. The DNA and RNA were extracted from these samples and subjected to polymerase chain reaction as well as reverse transcription polymerase chain reaction (RT-PCR) for detection of mumps virus, herpes viruses, and enteroviruses. Nine of the samples (3 mumps-positive and 6 enterovirus-positive) were sequenced. The mumps virus sequences were investigated for possible mutations in the SH and partial HN regions.Up to 39 patients (59.09%) were found to be positive for enteroviruses, 3 (4.5%) for mumps virus, and 1 (1.5%) for herpes viruses (specifically, the varicella-zoster virus). Two patients (3.03%) had a mumps virus and enterovirus coinfection. Among the 3 detected mumps virus samples, 1 belonged to genotype B, while the others belonged to genotype N. Six sequenced enteroviruses indicated the highest similarity with Echovirus 30. An amino acid substitution at position 51 (N→T) was detected in the HN region of genotype N mumps virus samples, in comparison to the reference strain.

[Epidemiology, etiology and clinical picture of enteroviral meningitis in children in South Moravia]

OBJECTIVES

Enteroviruses (EVs) are the most common cause of aseptic viral meningitis. In some cases, they can cause severe meningoencephalitis and acute flaccid paralysis - an association with some virulent serotypes. The objectives were to describe the epidemiological situation of EV meningitis in children in South Moravia, to elucidate the etiology including the incidence of virulent serotypes and to evaluate the clinical presentation.

MATERIAL AND METHODS

A total of 88 children with EV meningitis were prospectively evaluated. In case of aseptic inflammation in the cerebrospinal fluid, EV was detected using real-time PCR. Genotyping was performed in 56 samples using repeated one-step PCR and partial sequencing on a genetic analyzer in the National Reference Laboratory for Enteroviruses in Prague.

RESULTS

The patients' age range was 3-17 years; there were more boys than girls. Two epidemics occurred, one involving 17 Roma children and the other involving 8 swimming pool visitors. The most common symptoms were headache, fever and stiff neck. The most frequently (59%) detected agent was Echovirus 30 identified as the cause of the epidemics. In one boy, EV 71 (virulent serotype) was found. The clinical course did not vary from that in other serotypes. All 88 children recovered without complications.

CONCLUSIONS

EVs are an important part of the differential diagnosis of neuroinfections, although most infections are benign aseptic meningitis. The clinical presentation did not vary between infections with various serotypes. Higher incidence rates of virulent serotypes were not reported. Echovirus 30 was detected most frequently and was repeatedly identified as the cause of epidemics throughout the Czech Republic.

The role of the biochemistry department in the diagnosis of pituitary apoplexy

A 47-year-old man presented with severe clinical hypoglycaemia. He had long-standing insulin-dependent diabetes with previously good glycaemic control. Intense headaches and vomiting initiated hospitalization. A brain computed tomography (CT) scan was normal, and a lumbar puncture showed elevated cerebrospinal fluid (CSF) protein [0.67 g/L; normal range (NR) 0.15-0.45 g/L], suggesting resolving viral meningitis.

Routine thyroid function tests were abnormal (free thyroxine 10.6 pmol/L, NR 9-22.5 pmol/L; thyroid-stimulating hormone 0.16 mU/L, NR 0.35-5 mU/L). In the absence of evident thyroid therapy, the laboratory policy required an urgent cortisol assay to be added; this was very abnormal (42 nmol/L), suggesting hypopituitarism. Later analysis showed that concentrations of gonadotrophins and adrenocorticotrophin were low. An urgent pituitary magnetic resonance imaging scan revealed an unsuspected pituitary tumour with recent haemorrhage (pituitary apoplexy). The patient was given intravenous hydrocortisone and then stabilized on oral hydrocortisone, thyroxine and mesterolone. He made a full recovery and the hypoglycaemia resolved.

The normal brain CT scan was falsely reassuring and the CSF protein was not due to viral meningitis but to haemorrhage into the pituitary tumour. If laboratory policy had not required the urgent cortisol assay be added, the diagnosis of hypopituitarism would have been delayed or even missed altogether. This could have led to the death of the patient.

[Management of suspected meningitis in the emergency department]

Febrile meningeal syndrome is a medical emergency. Lumbar puncture keeps its gold-standard status as clinical findings are neither sensitive nor specific enough. Antibiotics and steroids are ideally administered within the first 30 minutes after admission when bacterial meningitis is suspected. A cerebral CT-scan before lumbar puncture is mandatory for selected patients only. PCR for viruses in the cerebrospinal fluid can inform diagnosis and treatment. Meningitis caused by enterovirus can usually be managed at home.

ASEPTIC MENINGITIS IN ADULTS CAUSING BY VIRUS, BACTERIA, DRUG WITH SPECIAL REFERENCES TO ZOONOTIC PARASITES

Diagnosis of a patient with aseptic meningitis may be so-difficult because of the large vanety of potential etiologic agents as viruses, fungi, parasites and some drugs and the overlap between self-limited viral illnesses and potentially fatal bact~nial infections.

Usefulness of blood and cerebrospinal fluid laboratory testing to predict bacterial meningitis in the emergency department

INTRODUCTION

The classic clinical presentation of bacterial meningitis (BM) is observed in less than half of the cases in adults, and symptoms are less specific in children, the elderly or immunocompromised, and other chronic patients. The usual signs and symptoms do not provide optimal sensitivity and specificity for distinguishing possible BM from viral meningitis (VM), which may lead to a delay in the appropriate antimicrobial therapy. Society therefore stands to benefit from the development of effective, objective, and rapid tools able to predict and identify patients with BM. These tools include laboratory tests for blood and cerebrospinal fluid (CSF). The aim of this review is to summarise recently published scientific evidence in order to clarify existing controversies and compare the usefulness and diagnostic ability of the different parameters used to predict BM.

DEVELOPMENT

Systematic search of the main bibliographic databases and platforms to identify articles published between January 2000 and January 2016. We selected 59 articles that meet the objectives of this review.

CONCLUSIONS

CSF lactate, proportion of polymorphonuclear leukocytes, and CSF glucose, as well as serum procalcitonin (PCT), are the independent factors most predictive of bacterial aetiology. The model that combines serum PCT and CSF lactate achieves the highest predictive power for BM, with a sensitivity and specificity exceeding 99%. We should consider BM when CSF lactate >33 md/dL and/or PCT>0.25ng/mL.

Cerebro-meningeal infections in HIV-infected patients: a study of 116 cases in Libreville, Gabon

BACKGROUND

Cerebro-meningeal pathology is common in human immunodeficiency virus (HIV) infection and the aetiology is often difficult to ascertain with certainty.

OBJECTIVE

To describe the major suspected and identified causes of meningeal or encephalitic syndromes in HIV infection in Libreville, Gabon.

METHODS

A descriptive study using clinical records of patients hospitalised in the Department of Medicine in the Military Hospital of Libreville (Gabon) between January 2006 and May 2010. Clinical features were evaluated using multivariable logistic regression to evaluate association with the outcome of a clinical improvement or death.

RESULTS

The most frequent neurological symptoms were reduced level of consciousness (54.3%), headache (55.2%), motor deficit (38.7%), and convulsions (36.2%). Cerebral toxoplasmosis represented 64.7% of diagnoses, followed by cryptococcal neuromeningitis in 12.9% of cases. Tuberculoma was diagnosed in 4 cases and lymphoma in 2 cases. In 9.5% of cases, no aetiology was determined. Toxoplasmosis treatment led to clinical improvement in 69.3% of cases with suspected cerebral toxoplasmosis. Overall mortality was 39.7%.

CONCLUSION

The diagnosis of neurological conditions in HIV positive patients is difficult, particularly in a low-resource setting. A trial of treatment for toxoplasmosis should be initiated first line with all signs of neurological pathology in a patient infected with HIV.

Calgary Experience with West Nile Virus Neurological Syndrome During the Late Summer of 2003

Background:

Between August 25 and September 25, 2003 seven patients with West Nile virus neurological manifestations were identified through the hospital neurology consultation services in Calgary, Alberta, Canada. Three of the seven patients were treated with interferon alpha-2b (IFN alpha-2b). In this report we document the clinical characteristics of these seven cases.

Methods:

Clinical and laboratory information was obtained from a retrospective review of patient hospital and clinic charts. Patients were included if they had serological evidence of West Nile virus infection and had clinical evidence of aseptic meningitis, encephalomyelitis, cerebellar syndrome or motor neuronopathy. Three patients received a treatment course of three million units IFN alpha-2b, administered by subcutaneous injection once per day for 14 days.

Results:

Four patients had cerebellar signs without change in consciousness, two had both encephalitis and neuromuscular weakness, and one patient had focal lower motor neuron arm weakness. The mean age was 52 (range 24 - 73). All patients had flu-like illness and fever as presenting symptoms and six had severe headaches. Two patients were immunocompromised prior to infection. Two patients with cerebellar signs (one with opsoclonus-myoclonus) improved spontaneously and exhibited only mild residual deficits on discharge. The other two patients with cerebellar findings developed brainstem involvement, one coinciding with and one subsequent to the cerebellar symptoms. Within one week of treatment with IFN alpha-2b these latter two patients showed marked improvement. One patient with encephalitis and neuromuscular weakness, was treated with IFN alpha-2b and subsequently recovered.

Interpretation:

In this case review of seven patients, multiple neurological symptoms occurred in each patient and the neurological presentation was varied. Four patients had predominant cerebellar findings and one patient had opsoclonus-myoclonus, not previously reported. The marked improvement in three patients who received IFN alpha-2b raises preliminary optimism towards this potential treatment.