Nosocomial ventriculitis and meningitis in neurocritical care patients. J Neurol. 2008;255:1617-1624. [PMID: 19156484 DOI: 10.1007/s00415-008-0059-8]

Complications of Intracranial Multimodal Monitoring for Neurocritical Care: A Systematic Review and Meta-Analysis

Intracranial multimodal monitoring (iMMM) is increasingly used for neurocritical care. However, concerns arise regarding iMMM invasiveness considering limited evidence in its clinical significance and safety profile. We conducted a synthesis of evidence regarding complications associated with iMMM to delineate its safety profile. We performed a systematic review and meta-analysis (PROSPERO Registration Number: CRD42021225951) according to the Preferred Reporting Items for Systematic Review and Meta-Analysis and Peer Review of Electronic Search Strategies guidelines to retrieve evidence from studies reporting iMMM use in humans that mention related complications. We assessed risk of bias using the Newcastle-Ottawa Scale and funnel plots. The primary outcomes were iMMM complications. The secondary outcomes were putative risk factors. Of the 366 screened articles, 60 met the initial criteria and were further assessed by full-text reading. We included 22 studies involving 1206 patients and 1434 iMMM placements. Most investigators used a bolt system (85.9%) and a three-lumen device (68.8%), mainly inserting iMMM into the most injured hemisphere (77.9%). A total of 54 postoperative intracranial hemorrhages (pooled rate of 4%; 95% confidence interval [CI] 0-10%; I2 86%, p < 0.01 [random-effects model]) was reported, along with 46 misplacements (pooled rate of 6%; 95% CI 1-12%; I2 78%, p < 0.01) and 16 central nervous system infections (pooled rate of 0.43%; 95% CI 0-2%; I2 64%, p < 0.01). We found 6 system breakings, 18 intracranial bone fragments, and 5 cases of pneumocephalus. Currently, iMMM systems present a similar safety profile as intracranial devices commonly used in neurocritical care. Long-term outcomes of prospective studies will complete the benefit-risk assessment of iMMM in neurocritical care. Consensus-based reporting guidelines on iMMM use are needed to bolster future collaborative efforts.

Niosomes: A Smart Drug Delivery System for Brain Targeting

Niosomes are lipid-based nanovesicles that have the potential to act as drug-delivery vehicles for a variety of agents. They are effective drug delivery systems for both ASOs and AAV vectors, with advantages such as improved stability, bioavailability, and targeted administration. In the context of brain-targeted drug delivery, niosomes have been investigated as a drug delivery system for brain targeting, but more research is needed to optimize their formulation to improve their stability and release profile and address the challenges of scale-up and commercialization. Despite these challenges, several applications of niosomes have demonstrated the potential of novel nanocarriers for targeted drug delivery to the brain. This review briefly overviews the current use of niosomes in treating brain disorders and diseases.

External ventriculostomy-associated infection reduction after updating a care bundle

BACKGROUND

Despite the clinical benefits of external ventricular drains (EVD), these devices can lead to EVD-related infections (EVDRI). The drainage insertion technique and standardized guidelines can significantly reduce the risk of infection, mainly caused by gram-positive bacteria. However, gram-negative microorganisms are the most frequent causative microorganisms of EVDRI in our hospital. We aimed to determine whether a new bundle of measures for the insertion and maintenance of a drain could reduce the incidence of EVDRI. This cohort study of consecutive patients requiring EVD from 01/01/2015 to 12/31/2018 compared the patients' characteristics before and after introducing an updated protocol (UP) for EVD insertion and maintenance in 2017.

RESULTS

From 204 consecutive patients, 198 requiring EVD insertion were included (54% females, mean age 55 ± 15 years). The before-UP protocol included 87 patients, and the after-UP protocol included 111 patients. Subarachnoid (42%) and intracerebral (24%) hemorrhage were the main diagnoses at admission. The incidence of EVDRI fell from 13.4 to 2.5 episodes per 1000 days of catheter use. Gram-negative bacteria were the most frequent causative microorganisms. Previous craniotomy remained the only independent risk factor for EVDRI. EVDRI patients had increased mechanical ventilation durations, hospital and ICU stays, and percutaneous tracheostomy requirements.

CONCLUSIONS

A care bundle focusing on fewer catheter sampling and more accurate antiseptic measures can significantly decrease the incidence of EVDRI. After implementing the management protocol, a decreased incidence of infections caused by gram-negative and gram-positive bacteria and reduced ICU and hospital lengths of stay were observed.

Plasma and Cerebrospinal Fluid Population Pharmacokinetics of Vancomycin in Patients with External Ventricular Drain

Vancomycin is a commonly used antibacterial agent in patients with primary central nervous system (CNS) infection. This study aims to examine predictors of vancomycin penetration into cerebrospinal fluid (CSF) in patients with external ventricular drainage and the feasibility of CSF sampling from the distal drainage port for therapeutic drug monitoring. Fourteen adult patients (9 with primary CNS infection) were treated with vancomycin intravenously. The vancomycin concentrations in blood and CSF (from proximal [CSF_P] and distal [CSF_D] drainage ports) were evaluated by population pharmacokinetics. Model-based simulations were conducted to compare various infusion modes. A three-compartment model with first-order elimination best described the vancomycin data. Estimated parameters included clearance (CL, 4.53 L/h), central compartment volume (Vc, 24.0 L), apparent CSF compartment volume (VCSF, 0.445 L), and clearance between central and CSF compartments (QCSF, 0.00322 L/h and 0.00135 L/h for patients with and without primary CNS infection, respectively). Creatinine clearance was a significant covariate on vancomycin CL. CSF protein was the primary covariate to explain the variability of QCSF. There was no detectable difference between the data for sampling from the proximal and the distal port. Intermittent infusion and continuous infusion with a loading dose reached the CSF target concentration faster than continuous infusion only. All infusion schedules reached similar CSF trough concentrations. Beyond adjusting doses according to renal function, starting treatment with a loading dose in patients with primary CSF infection is recommended. Occasionally, very high and possibly toxic doses would be required to achieve adequate CSF concentrations, which calls for more investigation of direct intraventricular administration of vancomycin. (This study has been registered at ClinicalTrials.gov under registration no. NCT04426383).

Heparin-binding protein as a marker of ventriculostomy related infection and central nervous system inflammation in neuro-intensive care

OBJECTIVE

Diagnosis of ventriculostomy related infections (VRI) in the neuro-intensive care unit remains challenging and current biomarkers lack adequate precision. The aim of this study was to explore the potential of Heparin-binding protein (HBP) in cerebrospinal fluid (CSF) as a diagnostic biomarker of VRI.

METHODS

All patients treated with an external ventricular drain (EVD) between January 2009 and March 2010 at Skåne university hospital in Lund, Sweden, were consecutively included. CSF samples obtained during routine care were analyzed for HBP. VRI was defined as a positive bacterial microbiology test result on a CSF sample with an erythrocyte-corrected leukocyte count of > 50 × 10⁶/l. HBP levels at VRI diagnosis was compared to peak HBP levels in non-VRI controls.

RESULTS

In total, 394 CSF samples from 103 patients were analyzed for HBP. Seven patients (6.8%) fulfilled VRI criteria. Levels of HBP were significantly higher in VRI subjects (31.7 ng/mL [IQR 26.9-40.7 ng/mL]) compared to non-VRI controls (7.7 ng/mL [IQR 4.1-24.5 ng/mL]) (p = 0.024). The AUC of the receiver operating characteristic (ROC) curve was 0.76 (95% confidence interval [CI], 0.62-0.90). Among non-VRI patients, HBP was highest in patients with acute bacterial meningitis. Patients with subarachnoid hemorrhage displayed higher HBP levels than those with traumatic brain injury or shunt dysfunction.

CONCLUSIONS

HBP levels were higher in VRI subjects and varied between patients and different diagnoses. To validate the clinical usefulness and added value of HBP as a biomarker for VRI, the results need to be confirmed in larger studies with head-to-head comparisons to current biomarkers.

Cerebrospinal fluid penetration of fosfomycin in patients with ventriculitis: an observational study

BACKGROUND

For treatment of ventriculitis, vancomycin and meropenem are frequently used as empiric treatment but cerebrospinal fluid (CSF) penetration is highly variable and may result in subtherapeutic concentrations. Fosfomycin has been suggested for combination antibiotic therapy, but data are sparse, so far. Therefore, we studied CSF penetration of fosfomycin in ventriculitis.

METHODS

Adult patients receiving a continuous infusion of fosfomycin (1 g/h) for the treatment of ventriculitis were included. Routine therapeutic drug monitoring (TDM) of fosfomycin in serum and CSF was performed with subsequent dose adaptions. Demographic and routine laboratory data including serum and CSF concentrations for fosfomycin were collected. Antibiotic CSF penetration ratio as well as basic pharmacokinetic parameters were investigated.

RESULTS

Seventeen patients with 43 CSF/serum pairs were included. Median fosfomycin serum concentration was 200 [159-289] mg/L and the CSF concentration 99 [66-144] mg/L. Considering only the first measurements in each patient before a possible dose adaption, serum and CSF concentrations were 209 [163-438] mg/L and 104 [65-269] mg/L. Median CSF penetration was 46 [36-59]% resulting in 98% of CSF levels above the susceptibility breakpoint of 32 mg/L.

CONCLUSION

Penetration of fosfomycin into the CSF is high, reliably leading to appropriate concentrations for the treatment of gram positive and negative bacteria. Moreover, continuous administration of fosfomycin appears to be a reasonable approach for antibiotic combination therapy in patients suffering from ventriculitis. Further studies are needed to evaluate the impact on outcome parameters.

Ultrasonic optic disc height combined with the optic nerve sheath diameter as a promising non-invasive marker of elevated intracranial pressure

Background/aim: Patients with elevated intracranial pressure (ICP) tend to have optic disc edema and a thicker optic nerve sheath diameter (ONSD). However, the cut-off value of the optic disc height (ODH) for evaluating elevated ICP is not clear. This study was conducted to evaluate ultrasonic ODH and to investigate the reliability of ODH and ONSD for elevated ICP.

Methods: Patients suspected of having increased ICP and who underwent a lumbar puncture were recruited. ODH and ONSD were measured before lumbar puncture. Patients were divided according to elevated and normal ICP. We analyzed the correlations between ODH, ONSD, and ICP. ODH and ONSD cut-off points for the identification of elevated ICP were determined and compared.

Results: There were a total of 107 patients recruited for this study, 55 patients with elevated ICP and 52 with normal ICP. Both ODH and ONSD in the elevated ICP group were higher than in the normal group [ODH: median 0.81 (range 0.60–1.06) mm vs. 0.40 [0–0.60] mm, p &lt; 0.001; ONSD: 5.01 ± 0.37 mm vs. 4.20 ± 0.38 mm, p &lt; 0.001]. ICP was positively correlated with ODH (r = 0.613; p &lt; 0.001) and ONSD (r = 0.792; p &lt; 0.001). The cut-off values of ODH and ONSD for evaluating elevated ICP were 0.63 mm and 4.68 mm, respectively, with 73% and 84% sensitivity and 83% and 94% specificity, respectively. ODH combined with ONSD showed the highest value under the receiver operating characteristic curve of 0.965 with a sensitivity of 93% and a specificity of 92%.

Conclusion: Ultrasonic ODH combined with ONSD may help monitor elevated ICP non-invasively.

Characteristics and outcomes of cerebrospinal fluid shunt and drain-associated infections

INTRODUCTION

Data on infections associated with cerebrospinal fluid shunt (CSF-S) or device-associated infection (CSF-SDI) are limited in adults. We performed a retrospective study to describe characteristics, management, and outcome of CSF-SDI.

METHODS

All patients with CSF-SDI and admitted to our institution from January 2013 to December 2019 were included.

RESULTS

Among 50 patients, fifty-six episodes of CSF-SDI (41 external ventricular device-associated infections (CSF-D) and 15 other shunt infections (CSF-S) were included. The incidence of CSF-SDI was 11.9 %. Fever was the most common symptom (81 %). Enterobacterales were more prevalent in CSF-S than in CSF-D (20 % vs 53 %, p = 0.02). As regards CSF-D, deceased patients (11/41, 27 %) more frequently had a Glasgow coma scale score decreasing from baseline (p < 0.01), lower glycorrhachia (p < 0.01), a higher protein level in CSF (p = 0.001) and a positive control CSF culture (p = 0.031).

CONCLUSIONS

CSF-SDIs are rare but with a high mortality rate. Mortality was more closely related to the infection than to comorbidities or underlying neurosurgical disease. A second CSF analysis significantly helped to detect patients with CSF-D with a poor prognosis.

Ultrasonic optic nerve sheath diameter could improve the prognosis of acute ischemic stroke in the intensive care unit

Objectives: Stroke patients with high intracranial pressure (ICP) may have poor prognosis. Non-invasive ultrasonic optic nerve sheath diameter (ONSD) could evaluate increased ICP. To investigate whether ONSD is valuable for prognosis of patients with acute ischemic stroke (AIS). Methods: AIS receiving intensive care were recruited with the Glasgow Coma Scale (GCS) score. Patients in group A underwent ultrasonic ONSD to assess ICP voluntarily, whereas group B without ONSD. Patients were followed up at discharge and once a week for 3 months with Glasgow Outcome Scale (GOS) score (four to five scores indicated good prognosis and one to three scores indicated poor prognosis). Results: Forty-nine patients were included. GCS scores did not differ significantly between groups A (26 patients) and B (8 ± 3 vs. 7 ± 3, p < 0.05). In group A, ONSD was 5.01 ± 0.48 mm, which correlated with GCS score (p < 0.05). At discharge, the GOS score was higher in group A than in group B (3.35 ± 1.35 vs. 2.57 ± 1.121, p = 0.034). The proportion of patients with a good prognosis was higher in group A than in group B (46.2% vs. 13.0%, p = 0.006). At discharge and after 3 months of follow-up, ONSD at admission was correlated with the GOS score in group A (r = -0.648 [p < 0.05] and -0.731 [p < 0.05], respectively). After 3 months of follow-up, the GOS score was higher in group A than group B (3.00 ± 1.673 vs. 2.04 ± 1.430, p < 0.05). The proportion of patients with a good prognosis was higher in group A than in group B (46.2% vs. 21.2%, p = 0.039). The Kaplan-Meier curve showed a higher rate of good prognosis in group A than in group B. ONSD (p < 0.05) was an independent predictor of poor prognosis. Conclusion: Non-invasive ultrasonic ONSD could be useful in improving the prognosis of patients with AIS receiving intensive care.

Cerebrospinal fluid white cell count to red cell count ratio as a predictor of ventriculitis in patients with external ventricular drains

INTRODUCTION

External ventricular drain (EVD) associated ventriculitis is a complication of EVD placement associated with significant morbidity and mortality. Gold-standard for EVD associated bacterial ventriculitis diagnosis involves cerebrospinal fluid (CSF) sampling from the EVD with microscopy, culture and sensitivity testing. The ratio of white blood cells to red blood cells has anecdotally been considered a predictive factor in diagnosing EVD associated ventriculitis, however no study has been done demonstrating this.

METHODS

A retrospective cross-sectional study was designed to assess whether the ratio of CSF white blood cells to red blood cells could be used to diagnose EVD associated ventriculitis. Data was collected for all patients undergoing EVD insertion at a major neurosurgical unit in Sydney, Australia. A receiver operator characteristics (ROC) curve was used to determine if this ratio was useful, and Youden's index was calculated to determine the appropriate cut-off point.

RESULTS

This sample of n = 157 consecutive patients a total of 29 patients were diagnosed with ventriculitis. The area under the ROC curve was significant (0.706, P <0.001), and Youden's index demonstrated an appropriate cut-off point was a ratio of 1:106.

DISCUSSION

CSF parameters have long been considered predictive of EVD associated ventriculitis. We demonstrated that using a component of routine testing it is possible to accurately predict a ventriculitis diagnosis. As the ratio is used, it enables discrimination in a raised white blood cell count due to local trauma with interventricular bleeding.

CONCLUSION

CSF white blood cell to red blood cell ratio is an appropriate diagnostic test for ventriculitis.

Ventriculosubgaleal shunting for spontaneous intraventricular haemorrhage: is it a good alternative to external ventricular drainage?

Background

Spontaneous intraventricular haemorrhage (IVH) is a life-threatening condition associated with high morbidity and mortality and is conventionally managed using external ventricular drain (EVD). However, EVD is commonly associated with a high rate of complications, which necessitates another alternative management with a comparable or better outcome. This study aims to compare the efficacy and safety of ventriculosubgaleal shunt (VSGS) compared to EVD for the management of adult patients with spontaneous IVH.

Results

A total of 48 patients were enrolled in this study. Twenty patients underwent EVD and 28 had VSGS. Postoperative complications were non-significantly more prevalent in the EVD than in the VSGS group (75 vs. 64.3%, p = 0.430), including non-CR (20 vs. 32.1%), infection (20 vs. 7.1%), blocked ventricular catheter (15 vs. 3.6%), and dislodged catheter (10 vs. 7.1%). Convulsions and CSF leaks occurred more frequently in the VSGS group (7.1 vs 5%, p = 1.000). Postoperative GCS and Graeb’s score were comparable between the groups (p > 0.05). The EVD group had a non-significantly higher rate of hydrocephalus after ventricular catheter removal (80 vs. 53.6%, p = 0.059) and a higher mean GOS 3 months postoperatively (mean score: 4 vs. 3).

Conclusions

VSGS is as effective and safe compared to EVD, with a lower rate of infection, blocked/dislodged catheters, as well as a reduced incidence of hydrocephalus. On the other hand, EVD showed better GOS at 3 months. However, these differences did not reach statistical significance.

Autologous Free Fascia Lata Can Be Used as Dura Graft in the Salvage Treatment of Recalcitrant Postcraniotomy Intracranial Infection Caused by Multidrug-Resistant Gram-Negative Bacteria

Objective

The multidrug-resistant (MDR) gram-negative bacteria-induced intracranial infections after neurosurgical procedures represent a particular therapeutic challenge. Combining the removal of infected prosthetic meninge plus an appropriate antibiotic administration appears to be the only therapeutic strategy likely to succeed when the infection is complicated by artificial dura mater. This study aimed to assess the efficacy of free fascia lata as a substitute for dura reconstruction in the salvage treatment for such recalcitrant nosocomial infections.

Methods

The retrospective, observational study was conducted at Shanghai Tenth hospital. Patients with definite intracranial infection caused by MDR Gram-Negative bacteria who underwent salvage dura reconstruction using autologous free fascia lata were included in the study. Electronic medical data on clinical characteristics, underlying condition, bacterial culture, antibiotic susceptibilities, perioperative management, surgical techniques, outcome, and follow-up were collected and analyzed.

Results

19 patients were included in the study cohort. All these patients underwent salvage surgery, including removal of infected artificial dura substitute, achievement of complete dura seal with free fascia lata, and other adjunctive procedures to drain the CSF and infuse sensitive antimicrobial agents. Intraventricular or intrathecal administration of antibiotics, including Colistin (14 case), Tigecycline (1 case), Amikacin (1 case), was employed in 16 patients. The infection was cured in 17 patients. In-hospital death occurred in 3 patients. One died from multiple system/organ failure, 1 died from massive occipital ICH, 1 died from brain stem hemorrhage after ventricular-peritoneal shunt surgery. The patients remained without clinical evidence of recurrence during the follow-up period.

Conclusion

On the basis of a comprehensive approach to achieving prompt sterilization of causative pathogens and an optimal healing environment, free fascia lata can serve as a simpler but effective option for dura reconstruction even in the setting of a severe septic area for patients who otherwise need much more complicated and demanding tissue transfer surgery.

Antibiotic Prophylaxis and Incidence of Infection with External Ventricular Drains and Intra-Cranial Pressure Monitors

Objectives: Guidelines do not recommend extended antibiotic prophylaxis for external ventricular drains (EVD) or intra-cranial pressure (ICP) monitors. The study objective was to determine if infection rates are different for patients receiving antibiotic prophylaxis for EVD or ICP monitors. Patients and Methods: This single-center retrospective cohort reviewed intensive care unit patients who had an EVD or ICP monitor placed. Patients receiving antibiotic prophylaxis were compared with those who did not receive prophylaxis. The primary end point was incidence of central nervous system (CNS) infection. Results: Overall, 228 patients were included, 120 of whom received prophylaxis and 108 who did not receive prophylaxis. The primary end point of CNS infection was not different between groups (18 [17%] vs. 23 [19%]; p = 0.6236). Conclusions: Antibiotic prophylaxis was not associated with a decreased incidence of CNS infection in patients with EVD or ICP monitors. Evaluation of antibiotic use in this patient population is warranted to prevent resistance and adverse drug effects.

Efficacy of Vancomycin and Meropenem in Central Nervous System Infections in Children and Adults: Current Update

The current antimicrobial therapy of bacterial infections of the central nervous system (CNS) in adults and pediatric patients is faced with many pitfalls as the drugs have to reach necessary levels in serum and cross the blood-brain barrier. Furthermore, several studies report that different factors such as the structure of the antimicrobial agent, the severity of disease, or the degree of inflammation play a significant role. Despite the available attempts to establish pharmacokinetic (PK) modeling to improve the required dosing regimen for adults and pediatric patients, conclusive recommendations for the best therapeutic strategies are still lacking. For instance, bacterial meningitis, the most common CNS infections, and ventriculitis, a severe complication of meningitis, are still associated with 10% and 30% mortality, respectively. Several studies report on the use of vancomycin and meropenem to manage meningitis and ventriculitis; therefore, this review aims to shed light on the current knowledge about their use in adults and pediatric patients. Consequently, studies published from 2015 until mid-July 2021 are included, and data about the study population, levels of drugs in serum and cerebrospinal fluid (CSF), and measured PK data in serum and CSF are provided. The overall aim is to provide the readers a recent reference that summarizes the pitfalls and success of the current therapy and emphasizes the importance of performing more studies to improve the clinical outcome of the current therapeutical approach.

Incidence of emergency neurosurgical TBI procedures: a population-based study

BACKGROUND

The rates of emergency neurosurgery in traumatic brain injury (TBI) patients vary between populations and trauma centers. In planning acute TBI treatment, knowledge about rates and incidence of emergency neurosurgery at the population level is of importance for organization and planning of specialized health care services. This study aimed to present incidence rates and patient characteristics for the most common TBI-related emergency neurosurgical procedures.

METHODS

Oslo University Hospital is the only trauma center with neurosurgical services in Southeast Norway, which has a population of 3 million. We extracted prospectively collected registry data from the Oslo TBI Registry - Neurosurgery over a five-year period (2015-2019). Incidence was calculated in person-pears (crude) and age-adjusted for standard population. We conducted multivariate multivariable logistic regression models to assess variables associated with emergency neurosurgical procedures.

RESULTS

A total of 2151 patients with pathological head CT scans were included. One or more emergency neurosurgical procedure was performed in 27% of patients. The crude incidence was 3.9/100,000 person-years. The age-adjusted incidences in the standard population for Europe and the world were 4.0/100,000 and 3.3/100,000, respectively. The most frequent emergency neurosurgical procedure was the insertion of an intracranial pressure monitor, followed by evacuation of the mass lesion. Male sex, road traffic accidents, severe injury (low Glasgow coma score) and CT characteristics such as midline shift and compressed/absent basal cisterns were significantly associated with an increased probability of emergency neurosurgery, while older age was associated with a decreased probability.

CONCLUSIONS

The incidence of emergency neurosurgery in the general population is low and reflects neurosurgery procedures performed in patients with severe injuries. Hence, emergency neurosurgery for TBIs should be centralized to major trauma centers.

Spontaneous and postsurgical/traumatic Klebsiella pneumoniae meningitis: two distinct clinico-microbiological entities

OBJECTIVES

To analyze and compare the characteristics and outcomes of spontaneous meningitis (SM) versus postsurgical/traumatic meningitis (PSTM) due to Klebsiella pneumoniae.

METHODS

A retrospective multicentric cohort study of all K. pneumoniae meningitis cases managed between January 2007 and May 2018 was carried out in seven university hospitals in the Paris area. The microbiological characteristics of 16 available K. pneumoniae isolates were further analyzed, and the genomes of seven of those isolated from SM were sequenced.

RESULTS

Among 35 cases, 10 were SM and 25 were PSTM. SM cases more severe than PSTM cases, with higher septic shock (p = 0.004) and in-hospital mortality rates (p = 0.004). In contrast, relapse occurred in five patients from the PSTM group versus no patients from the SM group. All K. pneumoniae strains recovered from SM but none of those recovered from PSTM displayed hypervirulent phenotypic (positive string test) and genotypic (genes corresponding to capsular serotypes K1 or K2; virulence genes rmpA and iutA) characteristics (p < 0.0001). PSTM tended to be more frequently polymicrobial (p = 0.08) and caused by an extended-spectrum β-lactamase producing strain (p = 0.08) than SM.

CONCLUSIONS

SM and PSTM are two entities differing both from a clinical and a microbiological standpoint. SM appears to be a more serious infection, induced by hypervirulent K. pneumoniae strains.

Cerebrospinal fluid cell count variability is a major confounding factor in external ventricular drain-associated infection surveillance diagnostics: a prospective observational study

Background

External ventricular drain (EVD)-related infections (EVDIs) are feared complications that are difficult to rapidly and correctly diagnose, which can lead to unnecessary treatment with broad-spectrum antibiotics. No readily available diagnostic parameters have been identified to reliably predict or identify EVDIs. Moreover, intraventricular hemorrhage is common and affect cerebrospinal fluid (CSF) cellularity. The relationship between leukocytes and erythrocytes is often used to identify suspected infection and triggers the use of antibiotics pending results of cultures, which may take days. Cell count based surveillance diagnostics assumes a homogeneous distribution of cells in the CSF. Given the intraventricular sedimentation of erythrocytes on computed tomography scans this assumption may be erroneous and could affect diagnostics.

Aims

To evaluate the consistency of cell counts in serially sampled CSF from EVDs, with and without patient repositioning, to assess the effect on infection diagnostics.

Methods

We performed a prospective single-center study where routine CSF sampling was followed by a second sample after 10 min, allocated around a standard patient repositioning, or not. Changes in absolute and pairwise cell counts and ratios were analyzed, including mixed regression models.

Results

Data from 51 patients and 162 paired samples were analyzed. We observed substantial changes in CSF cellularity as the result of both resampling and repositioning, with repositioning found to be an independent predictor of bidirectional cellular change. Glucose and lactate levels were affected, however clinically non-significant. No positive CSF cultures were seen during the study. Thirty percent (30%) of patients changed suspected EVDI status, as defined by the cell component of local and national guidelines, when resampling after repositioning.

Conclusions

CSF cell counts are not consistent and are affected by patient movement suggesting a heterogeneity in the intraventricular space. The relationship between leukocytes and erythrocytes was less affected than absolute changes. Importantly, cell changes are found to increase with increased cellularity, often leading to changes in suspected EVDI status. Faster and more precise diagnostics are needed, and methods such as emerging next generation sequencing techniques my provide tools to more timely and accurately guide antibiotic treatment.

Trial Registration NCT04736407, Clinicaltrials.gov, retrospectively registered 2nd February 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03715-1.

Development of the "Hamburg Best Practice Guidelines for ICV-Enzyme Replacement therapy (ERT) in CLN2 Disease" Based on 6 Years Treatment Experience in 48 Patients

Intracerebroventricular enzyme replacement therapy (ICV-ERT) for CLN2 disease represents the first approved treatment for neuronal ceroid lipofuscinosis (NCL) diseases. It is the first treatment where a recombinant lysosomal enzyme, cerliponase alfa, is administered into the lateral cerebral ventricles to reach the central nervous system, the organ affected in CLN2 disease. If untreated, CLN2 children show first symptoms such as epilepsy and language developmental delay at 2-4 years followed by rapid loss of motor and language function, vision loss, and early death. Treatment with cerliponase alfa has shown to slow the rapid neurologic decline. However, the mode of administration by 4 hour-long intracerebroventricular infusions every 14 days represents a potentially greater risk of infection compared to intravenous enzyme replacement therapies. The Hamburg NCL Specialty Clinic was the first site worldwide to perform intracerebroventricular enzyme replacement therapy in children with CLN2 disease. In order to ensure maximum patient safety, we analysed data from our center from more than 3000 intracerebroventricular enzyme replacement therapies in 48 patients over 6 years with regard to the occurrence of device-related adverse events and device infections. Since starting intracerebroventricular enzyme replacement therapy, we have also developed and continuously improved the "Hamburg Best Practice Guidelines for ICV-Enzyme Replacement Therapy (ERT) in CLN2 Disease." Results from this study showed low rates for device-related adverse events and infections with 0.27% and 0.33%, respectively. Therefore, following our internal procedural guidelines has shown to improve standardization and patient safety of intracerebroventricular enzyme replacement therapy for CLN2 disease.

Ventriculitis: A Severe Complication of Central Nervous System Infections

BACKGROUND

Ventriculitis, a dreaded complication of brain abscess, meningitis, and various neurosurgical procedures, has attracted limited attention in the medical literature.

METHODS

This is a retrospective, single-center study. We screened the medical files of all patients who had a brain imaging report that included the word "ventriculitis" during years 2005-2019. Only patients with clinical, microbiological, and imaging features of ventriculitis were included. Data were collected through a standardized questionnaire.

RESULTS

Ninety-eight patients fulfilled inclusion criteria: 42 women and 56 men, and the median age was 60 years (interquartile range, 48-68). The primary mechanism for ventriculitis was classified as follows: brain abscess (n = 29, 29.6%), meningitis (n = 27, 27.6%), intraventricular catheter-related (n = 17, 17.3%), post-neurosurgery (n = 13, 13.3%), and hematogenous (n = 12, 12.2%). The main neuroimaging features were intraventricular pus (n = 81, 82.7%), ependymal enhancement (n = 70, 71.4%), and intraventricular loculations (n = 15, 15.3%). The main pathogens were streptococci (n = 44, 44.9%), Gram-negative bacilli (n = 27, 27.6%), and staphylococci (n = 15, 15.3%). In-hospital and 1-year mortality rates were 30.6% (n = 30) and 38.8% (n = 38), respectively. Neurological sequelae were reported in 34 of 55 (61.8%) survivors, including cognitive impairment (n = 11), gait disturbances (n = 9), paresis (n = 7), behavior disorder (n = 6), and epilepsy (n = 5). On multivariate analysis, age >65 years, Glasgow Coma Scale score <13 at initial presentation, status epilepticus, hydrocephalus, and positive cerebrospinal fluid culture were associated with 1-year mortality. We built a scoring system to stratify patients with ventriculitis into low risk (12.5%), intermediate risk (36.5%), and high risk (71.4%) of death.

CONCLUSIONS

Ventriculitis is a severe complication of brain abscess, meningitis, or neurosurgery, with an in-hospital mortality rate of 30% and neurological sequelae in 60% of survivors.

Nursing assistance in patient care with external ventricular drain: a scoping review

OBJECTIVES

to map the available evidence about nursing care aimed at adult patients using external ventricular drain.

METHODS

this is a review using the scoping review method.

RESULTS

Initially, 965 studies were identified and, after the eligibility criteria, a sample of 54 publications was obtained. Each of them was assessed according to GRADE, resulting in three studies with high quality; 14 with moderate quality; 32 with low quality; and five with very low quality. It was highlighted 20 nursing care subdivided into nine categories, namely: drainage system; bed positioning and mobilization; catheter care; monitoring of intracranial pressure; and medication administration.

CONCLUSIONS

the scoping review made it possible to identify the main nursing care directed to adult patients undergoing placement of external ventricular drain from the evidence available to date.

Predictors of ventriculostomy infection in a large single-center cohort

OBJECTIVE

External ventricular drain (EVD) placement is a common neurosurgical procedure. While this procedure is simple and effective, infection is a major limiting factor. Factors predictive of infection reported in the literature are not conclusive. The aim of this retrospective, single-center large series was to assess the rate and independent predictors of ventriculostomy-associated infection (VAI).

METHODS

The authors performed a retrospective chart review of consecutive patients who underwent EVD placement between January 2012 and January 2018.

RESULTS

A total of 389 patients were included in the study. The infection rate was 3.1% (n = 12). Variables that were significantly associated with VAI were EVD replacement (OR 10, p = 0.001), bilateral EVDs (OR 9.2, p = 0.009), duration of EVD placement (OR 1.1, p = 0.011), increased CSF output/day (OR 1.0, p = 0.001), CSF leak (OR 12.9, p = 0.001), and increased length of hospital stay (OR 1.1, p = 0.002). Using multivariate logistic regression, independent predictors of VAI were female sex (OR 7.1, 95% CI 1.1–47.4; p = 0.043), EVD replacement (OR 8.5, 95% CI 1.44–50.72; p = 0.027), increased CSF output/day (OR 1.01, 95% CI 1.0–1.02; p = 0.023), and CSF leak (OR 15.1, 95% CI 2.6–87.1; p = 0.003).

CONCLUSIONS

The rate of VAI was 3.1%. Routine CSF collection (every other day or every 3 days) and CSF collection when needed were not associated with VAI. The authors recommend CSF collection when clinically needed rather than routinely.

Effect of a bundle approach on external ventricular drain-related infection

BACKGROUND

Emergency placement of an external ventricular drain (EVD) is one of the most frequently performed neurosurgical procedures. EVD-related infection continues to be a major challenge causing significant morbidity and costs. Bundle approaches have been shown to reduce infection rates; however, they are still not widely used, and observation periods often were rather short.

METHODS

The present study evaluated the effect of a multi-item bundle approach for EVD placement and care on the occurrence of EVD-related infection. A before/after approach was used to compare groups of consecutive patients over 5-year epochs to control for bias and secondary confounding variables.

RESULTS

The number of patients in the group before implementation of the bundle approach was 141 and 208 thereafter. There were no statistical differences in demographic and other variables. While 41/141 patients (29.1%) had an EVD-related infection before, this was the case in only 10/208 patients (4.8%) thereafter (p < 0.0001). The EVD-related infection rate was reduced from 13.7/1000 catheter days to 3.2/1000, and the 50% probability of an EVD-related infection in correlation to the mean duration of EVD placement was significantly lower (p < 0.0001). Routine EVD replacement was not helpful to reduce EVD-related infection. EVD-related infection rates remained low also over the next 8 years after the study was finished.

CONCLUSIONS

The introduction of a multi-item bundle approach for EVD insertion and care resulted in a marked reduction of EVD-related infection. Long observation periods over 5 years and beyond confirm that short-term changes are sustained with continued use of such protocols.

Metagenomic Next-Generation Sequencing of Cerebrospinal Fluid for the Diagnosis of External Ventricular and Lumbar Drainage-Associated Ventriculitis and Meningitis

Metagenomic next-generation sequencing (mNGS) has become a widely used technology that can accurately detect individual pathogens. This prospective study was performed between February 2019 and September 2019 in one of the largest clinical neurosurgery centers in China. The study aimed to evaluate the performance of mNGS on cerebrospinal fluid (CSF) from neurosurgical patients for the diagnosis of external ventricular and lumbar drainage (EVD/LD)-associated ventriculitis and meningitis (VM). We collected CSF specimens from neurosurgical patients with EVD/LD for more than 24 h to perform conventional microbiological studies and mNGS analyses in a pairwise manner. We also investigated the usefulness of mNGS of CSF for the diagnosis of EVD/LD-associated VM. In total, 102 patients were enrolled in this study and divided into three groups, including confirmed VM (cVM) (39), suspected VM (sVM) (49), and non-VM (nVM) (14) groups. Of all the patients, mNGS detected 21 Gram-positive bacteria, 20 Gram-negative bacteria, and five fungi. The three primary bacteria detected were Staphylococcus epidermidis (9), Acinetobacter baumannii (5), and Staphylococcus aureus (3). The mNGS-positive coincidence rate of confirmed EVD/LD-associated VM was 61.54% (24/39), and the negative coincidence rate of the nVM group was 100% (14/14). Of 15 VM pathogens not identified by mNGS in the cVM group, eight were negative with mNGS and seven were inconsistent with the conventional microbiological identification results. In addition, mNGS identified pathogens in 22 cases that were negative using conventional methods; of them, 10 patients received a favorable clinical treatment; thus, showing the benefit of mNGS-guided therapy.

Toll-like receptor linked cytokine profiles in cerebrospinal fluid discriminate neurological infection from sterile inflammation

Rapid determination of an infective aetiology causing neurological inflammation in the cerebrospinal fluid can be challenging in clinical practice. Post-surgical nosocomial infection is difficult to diagnose accurately, as it occurs on a background of altered cerebrospinal fluid composition due to the underlying pathologies and surgical procedures involved. There is additional diagnostic difficulty after external ventricular drain or ventriculoperitoneal shunt surgery, as infection is often caused by pathogens growing as biofilms, which may fail to elicit a significant inflammatory response and are challenging to identify by microbiological culture. Despite much research effort, a single sensitive and specific cerebrospinal fluid biomarker has yet to be defined which reliably distinguishes infective from non-infective inflammation. As a result, many patients with suspected infection are treated empirically with broad-spectrum antibiotics in the absence of definitive diagnostic criteria. To begin to address these issues, we examined cerebrospinal fluid taken at the point of clinical equipoise to diagnose cerebrospinal fluid infection in 14 consecutive neurosurgical patients showing signs of inflammatory complications. Using the guidelines of the Infectious Diseases Society of America, six cases were subsequently characterized as infected and eight as sterile inflammation. Twenty-four contemporaneous patients with idiopathic intracranial hypertension or normal pressure hydrocephalus were included as non-inflamed controls. We measured 182 immune and neurological biomarkers in each sample and used pathway analysis to elucidate the biological underpinnings of any biomarker changes. Increased levels of the inflammatory cytokine interleukin-6 and interleukin-6-related mediators such as oncostatin M were excellent indicators of inflammation. However, interleukin-6 levels alone could not distinguish between bacterially infected and uninfected patients. Within the patient cohort with neurological inflammation, a pattern of raised interleukin-17, interleukin-12p40/p70 and interleukin-23 levels delineated nosocomial bacteriological infection from background neuroinflammation. Pathway analysis showed that the observed immune signatures could be explained through a common generic inflammatory response marked by interleukin-6 in both nosocomial and non-infectious inflammation, overlaid with a toll-like receptor-associated and bacterial peptidoglycan-triggered interleukin-17 pathway response that occurred exclusively during infection. This is the first demonstration of a pathway dependent cerebrospinal fluid biomarker differentiation distinguishing nosocomial infection from background neuroinflammation. It is especially relevant to the commonly encountered pathologies in clinical practice, such as subarachnoid haemorrhage and post-cranial neurosurgery. While requiring confirmation in a larger cohort, the current data indicate the potential utility of cerebrospinal fluid biomarker strategies to identify differential initiation of a common downstream interleukin-6 pathway to diagnose nosocomial infection in this challenging clinical cohort.

The Updated Role of the Blood Brain Barrier in Subarachnoid Hemorrhage: From Basic and Clinical Studies

Subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke associated with high mortality and morbidity. The blood-brain-barrier (BBB) is a structure consisting primarily of cerebral microvascular endothelial cells, end feet of astrocytes, extracellular matrix, and pericytes. Post-SAH pathophysiology included early brain injury and delayed cerebral ischemia. BBB disruption was a critical mechanism of early brain injury and was associated with other pathophysiological events. These pathophysiological events may propel the development of secondary brain injury, known as delayed cerebral ischemia. Imaging advancements to measure BBB after SAH primarily focused on exploring innovative methods to predict clinical outcome, delayed cerebral ischemia, and delayed infarction related to delayed cerebral ischemia in acute periods. These predictions are based on detecting abnormal changes in BBB permeability. The parameters of BBB permeability are described by changes in computed tomography (CT) perfusion and magnetic resonance imaging (MRI). K_ep seems to be a stable and sensitive indicator in CT perfusion, whereas K^trans is a reliable parameter for dynamic contrast-enhanced MRI. Future prediction models that utilize both the volume of BBB disruption and stable parameters of BBB may be a promising direction to develop practical clinical tools. These tools could provide greater accuracy in predicting clinical outcome and risk of deterioration. Therapeutic interventional exploration targeting BBB disruption is also promising, considering the extended duration of post-SAH BBB disruption.

Predictors of catheter-associated meningitis in pediatric patients after brain tumor surgery: A 10-year single center experience

OBJECTIVE

To evaluate the incidence of catheter-associated meningitis (CAM) in a pediatric population receiving brain tumor surgery, and to identify the major risk factors involved.

METHODS

We retrospectively analyzed the medical and radiological records of 205 pediatric patients who received 251 external ventricular drains (EVDs) between January 2008 and December 2017. All patients less than 18 years old who underwent cerebrospinal fluid (CSF) diversion in the course of brain tumor surgery were included. Patients with central nervous system infection (CNS) at the time of EVD insertion were excluded.

RESULTS

A total of 99 patients receiving 107 EVDs met the study selection criteria. Among this population, the incidence of CAM was 19.2%. Median time-to-infection was 5 days. CAM prolonged the period of drainage in 57.9% of the cases. An extended ICU stay (>3 days) was statistically significantly associated with the occurrence of CAM. In the multivariate analysis, the presence of a high-grade CNS tumor was a predictor of an extended intensive care unit (ICU) stay. Furthermore, CSF leakage along the catheter tunnel was an independent predictor of CAM.

CONCLUSION

Our data confirms CAM as a significant complication in the acute treatment of hydrocephalus associated with pediatric brain tumors. To limit the incidence of CAM, measures must be taken to prevent CSF leakage, particularly among patients with high-grade CNS tumors that are likely to stay longer in the ICU and need prompt postoperative radiotherapy and oncological treatment.

Association of Dexamethasone with Shunt Requirement, Early Disability, and Medical Complications in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Current guidelines do not support the routine use of corticosteroids in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, corticosteroids use in aSAH has been practiced at some centers by convention. The aim of the study was to determine the incidence of hydrocephalus requiring ventriculoperitoneal shunt (VPS) placement as well as functional outcome on discharge and adverse events attributed to corticosteroids in patients with aSAH treated with different dexamethasone (DXM) treatment schemes.

METHODS

We retrospectively analyzed 206 patients with aSAH stratified to three groups based on the DXM treatment scheme: no corticosteroids, short course of DXM (S-DXM; 4 mg every 6 h for 1 day followed by a daily total dose reduction by 25% and then by 50% on last day), and long course of DXM (L-DXM; 4 mg every 6 h for 5-7 days followed by reduction by 50% every other day). The primary outcome measure was the placement of a VPS, and the secondary outcome was a good functional outcome [modified Rankin Scale (mRS) 0-3] at hospital discharge. Safety measures were the incidence of infection (pneumonia, urinary tract infection, ventriculitis, meningitis), presence of delirium, and hyperglycemia.

RESULTS

There was no difference in the rate of external ventricular drain (EVD) (p = 0.164) and VPS placement (p = 0.792), nor in the rate of good outcome (p = 0.928) among three defined treatment regimens. Moreover, the median duration of treatment with EVD did not differ between subjects treated with no corticosteroids, S-DXM, and L-DXM (p = 0.905), and the probability of EVD removal was similar when stratified according to treatment regimens (log-rank; p = 0.256). Patients who received L-DXM had significantly more complications as compared to patients, who received no corticosteroids or S-DXM (78.4% vs. 58.6%; p = 0.005). After adjustment, L-DXM remained independently associated with increased risk of combined adverse events (OR = 2.72; 95%CI, 1.30-5.72; p = 0.008), infection (OR = 3.45; 95%CI, 1.63-7.30; p = 0.001) and hyperglycemia (OR = 2.05; 95%CI, 1.04-4.04; p = 0.039).

CONCLUSIONS

DXM use among patients with aSAH did not relate to the rate of EVD and VPS placement, duration of EVD treatment, and functional disability at discharge but increased the risk of medical complications.

Antimicrobial Essential Oil Formulation: Chitosan Coated Nanoemulsions for Nose to Brain Delivery

Brain infections as meningitis and encephalitis are attracting a great interest. Challenges in the treatment of these diseases are mainly represented by the blood brain barrier (BBB) that impairs the efficient delivery of even very potent drugs to reach the brain. The nose to the brain administration route, is a non-invasive alternative for a quick onset of action, and enables the transport of numerous medicinal agents straight to the brain thus workarounding the BBB through the highly vascularized olfactory region. In this report, Thymus vulgaris and Syzygium aromaticum essential oils (EOs) were selected to be included in chitosan coated nanoemulsions (NEs). The EOs were firstly analyzed to determine their chemical composition, then used to prepare NEs, that were deeply characterized in order to evaluate their use in intranasal administration. An in vitro evaluation against a collection of clinical isolated bacterial strains was carried out for both free and nanoemulsioned EOs. Chitosan coated NEs showed to be a potential and effective intranasal formulation against multi-drug resistant Gram-negative bacteria such as methicillin-susceptible Staphylococcus aureus and multi-drug resistant Gram-negative microorganisms including carbapenem-resistant Acinetobacter baumannii and Klebsiella pneumoniae.

CSF penetration of vancomycin in critical care patients with proven or suspected ventriculitis: a prospective observational study

BACKGROUND

Vancomycin is recommended for ventriculitis. However, penetration into the CNS is relatively poor.

OBJECTIVES

To investigate the population pharmacokinetics of vancomycin in serum and CSF in critical care patients with proven or suspected CNS infections from neurosurgical procedures.

PATIENTS AND METHODS

This was an observational pharmacokinetic study in critical care patients with proven or suspected CNS infections receiving intravenous vancomycin. Multiple blood and intraventricular CSF samples were collected. Population pharmacokinetic analysis and simulation were undertaken with ADAPT5 and Pmetrics.

RESULTS

A total of 187 blood and CSF samples were collected from 21 patients. The median (range) Cmax and Cmin concentrations in serum were 25.67 (10.60-50.78) and 9.60 (4.46-23.56) mg/L, respectively, with a median daily dose of 2500 (500-4000) mg. The corresponding median concentrations in CSF were 0.65 (<0.24-3.83) mg/L and 0.58 (<0.24-3.95) mg/L, respectively. The median AUC0-24 in serum and CSF was 455.09 and 14.10 mg·h/L, respectively. A three-compartment linear population pharmacokinetic model best fitted the observed data. Vancomycin demonstrated poor penetration into CSF, with a median CSF/serum ratio of 3% and high intersubject pharmacokinetic variability of its penetration.

CONCLUSIONS

Therapeutic drug monitoring in both serum and CSF and higher daily doses may be an option to ensure adequate trough levels and to optimize patient therapy. Novel dosing strategies designed to reduce renal toxicity, such as administration by continuous infusion, should be investigated in further clinical studies to avoid antibiotic underexposure in CSF.

Daptomycin Plasma and CSF Levels in Patients with Healthcare-Associated Meningitis

BACKGROUND

There are currently few data concerning the cerebrospinal fluid (CSF) penetration of daptomycin in patients with healthcare-associated meningitis. This study aims (1) to better characterize the pharmacokinetics of daptomycin in humans during a 7-day intravenous (IV) therapy course, and (2) to study the penetration of daptomycin in the CSF after IV infusion at the dose of 10 mg/kg.

RESULTS

In this prospective observational study, we enrolled nine patients with an implanted external ventricular drainage and a diagnosis of a healthcare-associated meningitis. Daptomycin was administered at 10 mg/kg for a maximum of 7 days. The pharmacokinetic of daptomycin was studied using a two-compartment population/pharmacokinetic (POP/PK) model and by means of a nonlinear mixed effects modeling approach. A large inter-individual variability in plasma area under the curve (Range: 574.7-1366.3 h mg/L), paralleled by high-peak plasma concentration (C_max) (all values > 60 mg/L), was noted. The inter-individual variability of CSF-AUC although significant (range: 1.17-6.81 h mg/L) was narrower than previously reported and with a late occurrence of CSF-C_max (range: 6.04-9.54 h). The terminal half-life between plasma and CSF was similar. t_max values in CSF did not show a high inter-individual variability, and the fluctuations of predicted CSF concentrations were minimal. The mean value for daptomycin penetration obtained from our model was 0.45%.

CONCLUSIONS

Our POP/PK model was able to describe the pharmacokinetics of daptomycin in both plasma and CSF, showing that daptomycin (up to 7 days at 10 mg/kg) has minimal penetration into central nervous system. Furthermore, the observed variability of AUC, t_max and predicted concentration in CSF was lower than what previously reported in the literature. Based on the present findings, it is unlikely that daptomycin could reach CSF concentrations high enough to have clinical efficacy; this should be tested in future studies.

Utility of the Cell Index in Predicting External Ventricular Drain-Related Ventriculo-Meningitis

BACKGROUND/OBJECTIVE

Ventriculo-meningitis (VM) is an important complication of external ventricular drains (EVDs) in neurosurgical patients. Consequences include increased morbidity, mortality, and duration of hospital stay. Early diagnosis of EVD-associated VM allows earlier treatment intervention. The cell index (CI) may provide a simple measure that overcomes the limitations of isolated cerebrospinal fluid (CSF) parameters and other diagnostic tests, allowing earlier prediction of VM.

METHODS

All patients admitted to a tertiary hospital and requiring EVD insertion during 2015 and 2016 were assessed for inclusion in this retrospective case-control study. Patients with a known or suspected intracranial infection were excluded. Of the 186 patients who underwent EVD insertion, 95 patients were included in the final cohort. Data pertaining to patient characteristics and laboratory indices were extracted from health records and the microbiology laboratory database. The CI was calculated as the ratio of temporally related CSF leukocytes/erythrocytes to peripheral blood leukocytes/erythrocytes. Data from patients with microbiologically confirmed VM were analyzed in comparison with those not developing VM during the course of their stay. Categorical and continuous variables with skewed distributions were analyzed by Chi square and Mann-Whitney tests, respectively.

RESULTS

EVD-associated VM developed in 7.4% of patients. The highest CSF CI (within 3 days prior to diagnosis of VM or at any time for those not developing VM) differed significantly between the two groups (16; IQR 10.8-48.5 vs. 3.3; IQR 1.0-12.8, respectively; p = .046). The area under the receiver operating characteristic curve (AUROC) for the highest CI was 0.727 (95% confidence interval [CI] 0.526-0.929; p = .027). A CI of 10.4 provided a sensitivity and specificity of 80.5% and 70.5%, respectively, for the early diagnosis of VM.

CONCLUSIONS

In neurosurgical patients with an EVD, the CSF CI significantly predicted the development of VM.

Evaluation of a commercial multiplex PCR for diagnosis of central nervous system (CNS) nosocomial infections

Nosocomial Central Nervous System (CNS) infections are often serious complications of neurosurgical procedures. Their diagnosis is complex and frequently based on microbiological culture. The aim of this work was to evaluate the effectiveness of the FilmArray® Blood Culture Identification (BCID) panel, a multiplex PCR designed to identify the most common etiologic agents of sepsis involved with nosocomial CNS infections. A total of ninety samples were analyzed with the BCID panel. The sensitivity and specificity achieved were 77.4% and 100% respectively, when compared with the reference method (culture). Based on the analysis of the melting curves, another cut-off was established improving sensitivity to 83.9% whilst maintaining 98.3% specificity. The BCID panel seems to be a helpful tool for the prompt diagnosis of CNS nosocomial infections. The cut-off proposed here can increase sensitivity, but further studies are required to confirm its effectiveness and its applicability in clinical microbiology laboratories.

Ventricular Catheter Tract Hemorrhage as a Risk Factor for Ventriculostomy-Related Infection

BACKGROUND

Ventriculostomy-related infection (VRI) is a feared complication of external ventricular drain (EVD) placement. Although many contributing factors to VRI have been examined, little is known whether there is an association between ventriculostomy-related catheter tract hemorrhage (VCTH) and VRI.

OBJECTIVE

To evaluate risk factors for VRI and assess possible correlations with VCTH.

METHODS

We performed a retrospective analysis of patients with EVD placement in a neurocritical care unit between 2011 and 2015. VRI was defined as clinical signs of infection with a positive cerebrospinal fluid gram stain and isolation of cerebrospinal fluid culture. VCTH was diagnosed by computed tomography immediately after EVD insertion.

RESULTS

A total of 247 patients with EVD were identified during the 5-yr study period. An association between VCTH and gram-negative VRI was identified (P = .02). Ten percent (25 of 247 patients) developed a VRI, and 7% (18 of 247 patients) had a VCTH. Of the 25 patients with VRI, 20% (n = 5) had a VCTH, compared to 6% (n = 13) of 222 patients who had an EVD placed but did not develop VRI. There were no significant differences in demographic and clinical factors except for multiple EVD insertions (P < .00001), EVD duration (P < .001), and hospital length of stay (P < .001).

CONCLUSION

VCTH is a potentially significant risk factor for VRI. Further analysis will be needed to confirm the strength of this association, and to delineate the possible mechanisms by which tract hemorrhage may serve as a nidus for bacterial penetration into the central nervous system.

Local complications of adjunct intrathecal antibiotics for nosocomial meningitis associated with gram-negative pathogens: a meta-analysis

Direct delivery of antibiotics to the ventricular system offers an alternative for the management of nosocomial meningitis. However, the available literature frequently results in controversial findings regarding its safety. The present meta-analysis aimed at summarizing the risk of local complications after the administration of intraventricular/intrathecal (IVT/IT) antibiotics for the treatment of ventriculitis/meningitis (VM) associated with gram-negative pathogens. We systematically searched the medical literature from 1964 until July 2018, for clinical studies reporting on complications after the index treatment. The quality of the eligible studies was classified as "high," "moderated," and "low" for randomized controlled trials, observational studies, and case series, respectively. The results were summarized as pooled frequencies, estimated by the random- or fixed-effects models, according to the inter-study heterogeneity. The publication bias was visualized in trim-and-fill funnel plots. Τhe analysis included twenty-three primary studies with 229 patients. The overall complication rate was as high as 0.13 (95% CI 0.08; 0.19, I² = 9%); chemical meningitis and seizures represented the majority of the complications, with an occurrence rate of 0.11 (95% CI 0.07; 0.17, I² = 0%) and 0.07 (95% CI 0.04; 0.12; I² = 0%), respectively. The meta-analysis was based on studies of "moderate" and "low" reporting quality, while the publication bias after inspecting of the funnel plots revealed significant asymmetry. The present review denotes the absence of large, high-quality studies in the field. Nevertheless, IVT/IT was associated with moderate morbidity, mainly attributed to chemical meningitis and seizures. Further high-quality studies are still required before this therapeutic modality becomes broadly established.

Risk Factors of External Ventricular Drainage-Related Infections: A Retrospective Study of 147 Pediatric Post-tumor Resection Patients in a Single Center

Background: External ventricular drainage (EVD) is common after brain surgery. However, the incidence of EVD-related infection (ERI) is still relatively high and can increase morbidity and mortality.

Objective: The objective of this study was to analyze ERI factors in pediatric population post-brain tumor surgery.

Methods: From January 2016 to December 2017, 147 patients <18 years old underwent tumor removal at Beijing Tiantan Hospital and had postoperative EVD. We recorded basic demographic data as well as several risk factors. We then analyzed whether these factors were related to ERI.

Results: Patients with a preoperative ventriculo-peritoneal (V-P) shunt, those with longer operation time, those who received blood transfusion, those with more frequent cerebrospinal fluid (CSF) sampling, and those with longer indwelling time of EVD had higher risks of infection (p < 0.05). Logistic regression analysis confirmed that a preoperative V-P shunt, operative duration, intraoperative blood transfusion, frequency of CSF sampling, and EVD duration were correlated with postoperative ERI (p < 0.05).

Conclusion: EVD should be removed as soon as possible and any unnecessary procedures should be avoided to reduce the infection rate. However, prophylactic treatment should be given in case patients do not meet the indication for EVD removal.

Significance of cerebrospinal fluid inflammatory markers for diagnosing external ventricular drain–associated ventriculitis in patients with severe traumatic brain injury

Objective

The aim of this study was to investigate the diagnostic potential of the inflammatory markers interleukin-6 (IL-6), total leukocyte count (TLC), and protein in the CSF and IL-6, C-reactive protein, and white blood cell count in the serum for the early diagnosis of ventriculitis in patients with traumatic brain injury (TBI) and an external ventricular drain compared with patients without ventriculitis.

Methods

Retrospective data from 40 consecutive patients with TBI and an external ventricular drain treated in the authors’ intensive care unit between 2013 and 2017 were analyzed. For all markers, arithmetical means and standard deviations, area under the curve (AUC), cutoff values, sensitivity, specificity, positive likelihood ratio (LR), and negative LR were calculated and correlated with presence or absence of ventriculitis.

Results

There were 35 patients without ventriculitis and 5 patients with ventriculitis. The mean ± SD IL-6 concentration in CSF was significantly increased, with 6519 ± 4268 pg/mL at onset of ventriculitis compared with 1065 ± 1705 pg/mL in patients without ventriculitis (p = 0.04). Regarding inflammatory markers in CSF, IL-6 showed the highest diagnostic potential for differentiation between the presence and absence of ventriculitis (AUC 0.938, cutoff 4064 pg/mL, sensitivity 100%, specificity 92.3%, positive LR 13, and negative LR 0), followed by TLC (AUC 0.900, cutoff 64.5 /µL, sensitivity 100%, specificity 80%, positive LR 5.0, and negative LR 0) and protein (AUC 0.876, cutoff 31.5 mg/dL, sensitivity 100%, specificity 62.5%, positive LR 2.7, and negative LR 0).

Conclusions

The level of IL-6 in CSF has the highest diagnostic value of all investigated inflammatory markers for detecting ventriculitis in TBI patients at an early stage. In particular, CSF IL-6 levels higher than the threshold of 4064 pg/mL were significantly associated with the probability of ventriculitis.

Intracranial pressure monitoring: Gold standard and recent innovations

Intracranial pressure monitoring (ICP) is based on the doctrine proposed by Monroe and Kellie centuries ago. With the advancement of technology and science, various invasive and non-invasive modalities of monitoring ICP continue to be developed. An ideal monitor to track ICP should be easy to use, accurate, reliable, reproducible, inexpensive and should not be associated with infection or haemorrhagic complications. Although the transducers connected to the extra ventricular drainage continue to be Gold Standard, its association with the likelihood of infection and haemorrhage have led to the search for alternate non-invasive methods of monitoring ICP. While Camino transducers, Strain gauge micro transducer based ICP monitoring devices and the Spiegelberg ICP monitor are the emerging technology in invasive ICP monitoring, optic nerve sheath diameter measurement, venous opthalmodynamometry, tympanic membrane displacement, tissue resonance analysis, tonometry, acoustoelasticity, distortion-product oto-acoustic emissions, trans cranial doppler, electro encephalogram, near infra-red spectroscopy, pupillometry, anterior fontanelle pressure monitoring, skull elasticity, jugular bulb monitoring, visual evoked response and radiological based assessment of ICP are the non-invasive methods which are assessed against the gold standard.

Peripheral white blood cell count as a screening tool for ventriculostomy-related infections

One of the most common complications following external ventricular drain (EVD) placement is infection. Routine cultures of cerebrospinal fluid (CSF) are often used to screen for infection, however several days may pass before infection is discovered. In this study, we compared the predictive value of daily recorded vital sign parameters and peripheral white blood count (WBC) in identifying ventriculostomy-related infections. Patients with EVDs who had CSF cultures for microorganisms performed between January 2011 and July 2017 were assigned to either an infected and/or uninfected study group. Clinical parameters were then compared using t-test, chi squared and multiple logistic regression analyses. Patients of any age and gender were included. One hundred seventy uninfected and 10 infected subjects were included in the study. Nine of the 10 infected patients had an elevated WBC (>10.4 × 10³/μL), with a significantly greater WBC (15.9 × 10³/μL) than the uninfected group (10.4 × 10³/μL) (p-value ≤ 0.0001). Using logistic regression, we found no association between patient vital signs and CSF infection except for WBC (p = .003). As a diagnostic marker for CSF infection, the sensitivity and specificity of WBC elevation greater than 15 × 10³/μL was 70% (7/10) and 90.2% (147/163), respectively. This study serves as a 'proof of concept' that WBC could be useful as potential screening tool for early detection of CSF infection post-EVD placement. Future investigation using a large, multicenter prospective study is needed to further assess the applicability of this parameter.

Cost of hospitalization for aneurysmal subarachnoid hemorrhage in the United States

OBJECTIVE

Recent large-scale studies describing hospitalization cost trends secondary to aneurysmal subarachnoid hemorrhage (aSAH) in the United States are lacking. We sought to discover the impact of aSAH-related factors upon its hospitalization cost.

PATIENTS AND METHODS

Patients with a primary diagnosis of aSAH were selected utilizing the National Inpatient Sample. Regression analyses were used to evaluate the impact of aSAH-related factors on hospitalization costs.

RESULTS

From 2002-2014, 22,831 cases of aSAH were identified. The inflation-adjusted mean cost of hospitalization was $82,514 (standard deviation ± $54,983). The proportion of males was lower (31%), but a higher cost of $3385 (± $685; p < .001) remained compared to females. Median length of hospitalization was 16 days (interquartile range 11-23) and each day increase in hospitalization was associated with a cost increase of $3228 (± $19; p < .001). There was no difference in cost between patients undergoing aneurysmal coiling or clipping. When compared to patients < 40 years old, the increase in cost for patients 40-59 years old was $3829 (± $914; p < .001), and $4573 (± $1033; p < .001) for patients 60-79 years old; however, for patients ≥ 80 years old, there was a decrease in cost of $8124 (± $1722; p < .001). Several central nervous system complications were also associated with increased cost.

CONCLUSION

aSAH is a significant financial burden on the United States healthcare system. We were able to identify many important factors associated with higher costs, and these results may help us understand resource utilization and develop future cost-reduction strategies.

Neutrophil CD64 index in cerebrospinal fluid as a marker of bacterial ventriculitis in children with external ventricular drainage

Background

Bacterial ventriculitis is a common complication in children with temporary external ventricular drains (EVD) and the diagnosis is challenging. The present study compared the diagnostic accuracy of novel cerebrospinal fluid (CSF) marker - CD64 expression on neutrophils measured as neutrophil CD64 index (CD64in) to routine laboratory CSF and blood markers for bacterial ventriculitis in children with EVD.

Methods

We conducted a prospective, observational study, enrolling children with EVD. CD64in in CSF together with CSF markers (leukocyte count, percentage of neutrophils, glucose, and proteins) and blood markers (leukocyte and differential count, C-reactive protein (CRP), and procalcitonin (PCT)) were studied at the time of suspected bacterial ventriculitis. CD64in was measured by flow cytometry. Diagnostic accuracy determined by the area under the receiver–operating characteristic (ROC) curves (AUC) was defined for each marker.

Results

Thirty-three episodes of clinically suspected ventriculitis in twenty-one children were observed during a 26-month period. Episodes were classified into those with microbiologically proven ventriculitis (13 episodes) and into those with microbiologically negative CSF (20 episodes). CD64in and leukocyte count were the only CSF markers that could differentiate between groups with diagnostic accuracy of 0.875 and 0.694, respectively. Among blood markers only CRP and band neutrophils differentiated between groups with diagnostic accuracy of 0.792 and 0.721, respectively.

Conclusions

CD64in in CSF is a promising diagnostic marker of bacterial ventriculitis in children with EVD as it has higher diagnostic accuracy than routine blood and CSF markers for diagnosing bacterial ventriculitis at the time of clinical suspicion.

Tumor necrosis factor alpha and interleukin-1 beta levels in cerebrospinal fluid examination for the diagnosis of ventriculoperitoneal shunt-related ventriculitis

PURPOSE

Ventriculitis is known to develop after chronic inflammation and bacterial invasion of the ventricular surface with a recurrence of shunt infections. The aim of this study is to evaluate the diagnostic value of elevation in cerebrospinal fluid (CSF) interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) together with CSF culture and laboratory test results in the diagnosis of ventriculoperitoneal (VP) shunt-related ventriculitis, which is known to be more problematic than conventional shunt infection.

METHODS

The study included a total of 34 patients with a VP shunt due to hydrocephalus, who presented with a headache, fever, and shunt infection at the Emergency Department and had a pre-diagnosis of ventriculitis. Nineteen patients were diagnosed with shunt-related infection or ventriculitis using the CSF obtained from the shunt pump. The IL-1β and TNF-α levels from the CSF samples of all patients were measured using the Micro ELISA immunoassay method.

RESULTS

CSF direct microscopic observation revealed that the mean cell count, IL-1β level, CRP level, and blood leukocyte level were higher in patients with ventriculitis compared to those diagnosed with shunt infection (p = 0.02, p = 0.009, p = 0.004, and p = 0.009, respectively). The probability of predicting positive culture outcome was 92.7% with 90.9% sensitivity and 82.6% specificity when IL-1β values exceeded 4.0 pg/ml. TNF-α values did not show a significant, reliable pattern compared to IL-1β.

CONCLUSIONS

IL-1β is a reliable parameter which shall be used in the diagnosis of ventriculitis by predicting positive culture outcome with high sensitivity and specificity.

Risk Factors of External Ventricular Drain Infection: Proposing a Model for Future Studies

Background: External ventricular drain (EVD) has a major role in the management and monitoring of intracranial pressure (ICP) and its major complication is EVD infection. The risk factors for EVD infection are still a major topic of controversy, hence the need for further research.

Objective: The objective of this review was to identify risk factors that affect the incidence of EVD infection and create a model, which can be used in future studies in order to contribute to elaborations on guideline for EVD.

Methods: A PubMed and Google Scholar literature search was performed and data were extracted from studies published from 1966 through 2017. The search of the databases generated 604 articles and 28 articles of these were found to be relevant. A manual search of the 28 relevant papers generated 4 new articles. Of the 32 relevant articles, 20 articles that performed a multivariate analysis of the suspected risk factors of EVD infection and had a positive culture as a mandatory component in diagnosis were selected for data collection and analysis.

Results: Because reviewed papers investigated only a few influencing factors, and could not determine convincingly the real risk factors of EVD infection and their real strengths. A total of 15 supposed influencing factors which includes: age, age & sex interactions, coinfection, catheter insertion outside the hospital, catheter type, CSF leakage, CSF sampling frequency, diagnosis, duration of catheterization, ICP > 20 mmHg, irrigation, multiple catheter, neurosurgical operation, reduced CSF glucose at catheter insertion and sex were identified.

Conclusion: This review summarizes a set of variables which have to be covered by future clinical epidemiological investigations in order to describe the etiological background of EVD infection.

Neurosurgical complications: what the radiologist needs to know

Visits to the emergency department by patients who have recently undergone neurosurgery are a common occurrence, and these patients frequently receive emergent cross-sectional head imaging in order to evaluate for complications. Different neurosurgical approaches may have typical postoperative imaging findings that can be confused with pathology. Furthermore, particular abnormal postoperative imaging findings may signal an evolving complication. It is essential for the radiologist to understand common neurosurgical procedures and their potential complications in order to provide proper diagnostic evaluation of the postoperative neurosurgical patient. The purpose of this review is to assist radiologists in the evaluation of the postoperative neurosurgical patient and educate them on associated complications. Familiarity with common neurosurgical techniques and postoperative complications will help radiologists make the correct diagnosis, communicate effectively with the neurosurgeon, and expedite patient care.

Impact of Antibiotic Therapy in the Microbiological Yield of Healthcare-Associated Ventriculitis and Meningitis

The impact of antibiotic therapy on the diagnosis of healthcare-associated ventriculitis and meningitis (HCAVM) is unknown. Antibiotics were administered before obtaining cerebrospinal fluid (CSF) in 217 out of 326 (66%) patients with HCAVM, and they impacted the sensitivity of the cerebrospinal fluid Gram stain and culture (P ≤ .004).

High-Dosage Cefazolin Achieves Sufficient Cerebrospinal Diffusion To Treat an External Ventricular Drainage-Related Staphylococcus aureus Ventriculitis

A patient received continuous infusion of cefazolin 10 g then 8 g daily for an external ventricular drainage-related methicillin-susceptible Staphylococcus aureus (MSSA) ventriculitis. Median free concentrations in the cerebrospinal fluid were 11.9 and 6.1 mg/liter after 10- and 8-g doses, respectively. Free concentrations in the cerebrospinal fluid were always above the MIC usually displayed by methicillin-susceptible Staphylococcus aureus (MSSA) isolates. These results support the use of high-dose cefazolin to achieve sufficient meningeal concentrations.