Comparison of Lumbar and Ventricular Cerebrospinal Fluid for Diagnosis and Monitoring of Meningitis.

Severe meningitis, especially basilar meningitis, can lead to hydrocephalus requiring external ventricular drain (EVD) placement. There are differences in cerebrospinal fluid (CSF) obtained from an EVD compared to a lumbar puncture (LP). Hence, it becomes difficult to compare LP and EVD samples for diagnosis and monitoring of meningitis. Recognizing these differences is important to properly treat and discontinue antibiotics. We report a case series of 6 patients with meningitis comparing EVD and LP CSF study analysis. In all 6 patients, CSF from LP was obtained before EVD placement by 1.7 days on average. Although corrected white blood cell (WBC) counts were elevated in CSF obtained from LP and EVD, the counts were significantly higher in LP CSF. Protein concentration in LP CSF was also significantly higher than EVD CSF. Glucose and red blood cells varied in both LP and EVD samples. Even though EVD CSF was obtained later in the clinical course than LP, slower circulation of CSF in lumbar space as compared to ventricles is likely the reason for a more sterile appearance of EVD CSF for the diagnosis of meningitis. It is important to recognize these differences as EVD CSF analysis for diagnosis of meningitis may lead to a missed diagnosis and false perception of significant improvement when monitoring response to treatment. One can consider repeating LP prior to discontinuation of antibiotics to properly determine the extent of improvement given EVD CSF sample appears more sterile in comparison. Larger studies are needed to confirm the above findings.

Nilotinib-Associated Atherosclerosis Presenting as Multifocal Intracranial Stenosis and Acute Stroke.

Nilotinib, a BCR-ABL tyrosine kinase inhibitor (TKI), has been associated with vascular events and accelerated arterial stenosis, presumably of atherosclerotic etiology. Studies of nilotinib-associated atherosclerosis are mainly associated with progressive peripheral artery occlusive disease (PAOD), and only a few cases of coronary artery disease (CAD), and cerebrovascular disease (CVD) have been reported. The mechanisms by which nilotinib promotes atherosclerosis are poorly understood but endothelial and perivascular factors, mast cell depletion, and metabolic factors such as promotion of dyslipidemia and impaired glucose metabolism are thought to play a role. We present a case of a patient with chronic myelogenous leukemia (CML) treated with nilotinib who developed intracranial atherosclerosis leading to acute onset of stroke. Our patient had no cardiovascular risk factors prior to treatment with nilotinib and developed accelerated atheromatous cerebrovascular disease with severe left middle cerebral artery (MCA) stenosis. These findings suggest that nilotinib may be associated with the development of intracranial atherosclerotic disease (ICAD) independently of any preexisting vascular risk factors leading to acute stroke. Clinicians should have increased awareness of the association between nilotinib and the development of progressive atheromatous disease and vascular adverse events including PAOD, CAD, and CVD. In certain patients, these events can be severe and life threatening. Thus, screening for vascular risk factors including CVD prior to starting nilotinib and close follow up during treatment is crucial.

Real-world experience with implantable loop recorder monitoring to detect subclinical atrial fibrillation in patients with cryptogenic stroke: The value of p wave dispersion in predicting arrhythmia occurrence.

PURPOSE: We hypothesized patients implanted with ILRs for cryptogenic stroke in "real life" clinical practice will show an AF detection rate comparable to prior clinical studies, and that clinical or imaging features may help to identify those at higher risk of AF detection. METHODS: A retrospective chart review was conducted of all patients who presented with cryptogenic stroke and received an ILR at an academic medical center from 2015 to 2017 with an active inpatient stroke service. The electronic health record and remote monitoring were used to identify occurrence of AF. RESULTS: A total of 178 patients who received ILRs for cryptogenic stroke were included. Overall, after a thorough evaluation for other etiologies of stroke, 35 (19.6%) were found to have AF detected. Mean follow-up was 365 days with a median time to detection of 131 days. Advanced age (p = 0.001), diastolic dysfunction on echo (p = 0.03), as well as ECG findings of premature atrial contractions (PACs) and p wave dispersion (PWD) > 40 ms were found to be predictive of AF detection (p = 0.04, p < 0.001, respectively). On multiple regression analysis, the only independent predictor of AF detection was PWD > 40 ms. CONCLUSION: After a thorough evaluation to exclude other etiologies for stroke, approximately 20% of patients of our cryptogenic stroke population were found to have AF with ILR surveillance. Advanced age, diastolic dysfunction, as well as ECG findings of PACs and increased PWD may help to predict those at higher risk of AF detection, while PWD was the only independent predictor. This has important clinical implications, as better prediction of AF may help identify those at highest risk and might subsequently aid in guiding therapy.

Would you use novel oral anticoagulants (NOACs) for thromboprophylaxis in patients with an underlying hypercoagulable state? A literature review through a case report.

Antiphospholipid syndrome (APLS) is an autoimmune condition that predisposes to venous and arterial thrombosis. Warfarin is the agent of choice for anticoagulation. However, a need for routine international normalised ratio (INR) checks and multiple drug interactions are some of the difficulties with warfarin. Currently, there is mixed evidence for and against the use of novel oral anticoagulants (NOACs) for thromboprophylaxis. We present a case report of a patient with APLS on a NOAC for secondary thromboprophylaxis who developed a stroke and discuss current evidence regarding the use of NOACs in patients with APLS. The patient was switched to warfarin for secondary thromboprophylaxis with an INR goal of 2-3. Literature review revealed mixed case reports for and against NOACs for secondary prevention of thrombotic events in patients with APLS. There needs to be further randomised controlled trials to evaluate the efficacy of NOACs for thromboprophylaxis in patients with APLS.

Mild encephalopathy with reversible splenium lesion (MERS) in a patient with COVID-19.

Neurological complications of coronavirus 2019 (COVID-19) are common, and novel manifestations are increasingly being recognized. Mild encephalopathy with reversible splenium lesion (MERS) is a syndrome that has been associated with viral infections, but not previously with COVID-19. In this report, we describe the case of a 69 year-old man who presented with fever and encephalopathy in the setting of a diffusion-restricting splenium lesion, initially mimicking an ischemic stroke. A comprehensive infectious workup revealed positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies, and a pro-inflammatory laboratory profile characteristic of COVID-19 infection. His symptoms resolved and the brain MRI findings completely normalized on repeat imaging, consistent with MERS. This case suggests that MERS may manifest as an autoimmune response to SARS-CoV-2 infection and should be considered in a patient with evidence of recent COVID-19 infection and the characteristic MERS clinico-radiological syndrome.

Inter-predictability of Neuroprognostic Modalities After Cardiac Arrest.

Introduction At present, there is an emphasis on a multi-modal approach to neuro-prognostication after cardiac arrest using clinical examination, neurophysiologic testing, laboratory biomarkers, and radiological studies. However, this necessitates significant resource utilization and can be challenging in under-resourced clinical settings. Hence, we sought to determine the inter-predictability and correlation of prognostic tests performed in patients after cardiac arrest. Methods Fifty patients were included through neurophysiology laboratory data for this retrospective study. Clinical, radiological and neurophysiological data were collected. Neurophysiological data were re-evaluated by a board-certified neurophysiologist for the purpose of the study. Chi-square testing was used to evaluate the correlation between different diagnostic modalities. Results We found that a non-reactive electroencephalogram (EEG) had a predictive value of 79% for absent bilateral cortical responses (N20) with somatosensory evoked potentials (SSEP). On the other hand, absent bilateral cortical responses N20 had 87% predictive value for a non-reactive EEG. Also, absent cortical responses and non-reactive EEG had predictive values of 78% and 72% for anoxic injury on magnetic resonance imaging (MRI) brain respectively with a non-significant difference on chi-square testing. Individually, absent bilateral N20 SSEP, a non-reactive EEG and anoxic brain injury on MRI studies were highly predictive of poor outcome [modified Rankin scale (mRS) > 4] at hospital discharge. Conclusion Neuroprognostication in a post-cardiac arrest setting is often limited by self-fulfilling prophecy. Given the lack of absolute correlation between different modalities used in post-cardiac arrest patients, the value of the multi-modal approach to neuro-prognostication is highlighted by this study.

Variations in retrieval monitoring during action memory judgments: evidence from event-related potentials (ERPs).

The present study investigated the neuroscience of memory for actions using event-related potentials (ERPs). Actions were performed, initiated but not completed (i.e., interrupted), or watched while the experimenter performed the action during encoding. Memory was assessed in a reality monitoring (RM) test (performed vs. watched actions), as well as in an internal source monitoring (ISM) test (performed vs. interrupted) while ERPs were recorded. Behavioral measures provided evidence of robust old/new recognition for all actions, but the analysis of source errors revealed that interrupted actions were often confused with performed actions. The ERP correlate of recollection, the parietal "old/new" effect (700-900ms), was observed for all actions. The right frontal "old/new" effect (1500-1800ms) that correlates with general memory monitoring was observed in RM but not in ISM. Instead, ISM was associated with the late posterior negativity (LPN) that has been connected to more specific memory monitoring. This pattern of ERP findings suggest that, in this context, general monitoring was used to discriminate self- versus other-performed actions, whereas more specific monitoring was required to support the discrimination of completed and interrupted actions. We argue that the mix of general/specific monitoring processes is shaped by the global retrieval context, which includes the number of memory features that overlap and the combination of sources being considered among other factors.