17Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has now spread across the 18 globe. As part of the worldwide response, many molecular diagnostic platforms have been granted 19Emergency Use Authorization (EUA) by the Food and Drug Administration (FDA) to identify SARS-CoV-2 20 positive patients. Our objective was to evaluate three sample-to-answer molecular diagnostic platforms 21 (Cepheid Xpert® Xpress SARS-CoV-2 [Xpert Xpress], Abbott ID NOW™ COVID-19 [ID NOW], GenMark 22 ePlex® SARS-CoV-2 Test [ePlex]) to determine analytical sensitivity, clinical performance, and workflow 23 for the detection of SARS-CoV-2 in nasopharyngeal swabs from 108 symptomatic patients. We found 24 that the Xpert Xpress had the lowest limit of detection (100% detection at 100 copies/mL), followed by 25 the ePlex (100% detection at 1,000 copies/mL), and the ID NOW (20,000 copies/mL). The Xpert Xpress 26 also had highest positive percent agreement (PPA) when compared to our reference standard (98.3%) 27 followed by the ePlex (91.4%) and ID now (87.7%). All three assays showed 100% negative percent 28 agreement (NPA). In the workflow analysis, the ID NOW produced the most rapid time to result per 29 specimen (~17 minutes) as compared to the Xpert Xpress (~46 minutes) and the ePlex (~1.5 hours), but 30 what the ID NOW gained in rapid results, it lost in analytical and clinical performance. The ePlex had the 31 longest time to results and showed a slight improvement in PPA over the ID NOW. Information about 32 the clinical and analytical performance of these assays, as well as workflow, will be critical in making 33 informed and timely decisions on testing platform. 34 35

SUMMARY Forty-three patients with multiple sclerosis showed disturbances in short-term memory, learning, and delayed recall which were associated with years of active disease (average was 4.5 years), age, presence of flareup, but not steroid/ACTH treatment. Unrecognised memory loss might be prevalent early in the natural history of multiple sclerosis and deserves neuropsychological assessment.Cognitive decline commonly occurs in the later stages of multiple sclerosis.' In the past three decades some of the qualitative and quantitative features of cognitive change have been delineated through neuropsychological inquiry. Many investigations of intelligence in multiple sclerosis have concluded that patients with demyelination show disproportionate drops in peformance IQ while maintaining relatively good verbal skills.2 More comprehensive neuropsychological studies, utilising procedures such as the Halstead-Reitan Battery revealed patients with multiple sclerosis to have marked motor and perceptual-motor integrative deficits, generally intact verbal-language skills, and variable decrements in abstracting ability.3'0 A century has passed since Charcot first observed "enfeeblement of memory" in his patients" and " 12Gowers wrote of their "failure of memory".Despite this, the neuropsychological research reviewed above has been singularly lacking in systematic assessment of memory. Surridge'3 noted from structured psychiatric examination that approximately two-thirds of his patients showed intellectual decline, with amnesia being a central problem. Jambor's'4 related psychometric study found deficits in sentence learning and delayed recall of nonverbal information. These observations Address for reprint requests: Professor I Grant, Psychiatry Service (116). V.A.

With the approach of respiratory virus season in the Northern Hemisphere, clinical microbiology and public health laboratories will need rapid diagnostic assays to distinguish SARS-CoV-2 from influenza and respiratory syncytial virus (RSV) infections for diagnosis and surveillance. In this study, the clinical performance of the Xpert® Xpress SARS-CoV-2/Flu/RSV test (Cepheid, Sunnyvale, CA, USA) for nasopharyngeal swab specimens was evaluated in four centers: Johns Hopkins Medical Microbiology Laboratory, Northwell Health Laboratories, NYC Public Health Laboratory, and Los Angeles County/University of Southern California (LAC+USC) Medical Center. A total of 319 nasopharyngeal swab specimens, positive for SARS-CoV-2 (n = 75), influenza A (n = 65), influenza B (n = 50), RSV (n = 38), or negative (n = 91) by the standard of care nucleic acid amplification tests at each site were tested using the Cepheid panel test. The overall positive percent agreement for the SARS-CoV-2 target was 98.7% (n= 74/75) and the negative agreement was 100% (n= 91) with all other analytes showing 100% total agreement (n= 153). Standard of care tests to which the Cepheid panel was compared included the Cepheid Xpert Xpress SARS-CoV-2, Cepheid Xpert Xpress Flu/RSV, the GenMark ePlex respiratory panel, the BioFire Respiratory panels 2.1 and v1.7, the DiaSorin Simplexa COVID-19 Direct, and the Hologic Panther Fusion SARS-CoV-2 assays. The Xpert Xpress SARS-CoV-2/Flu/RSV test showed high sensitivity and accuracy for all analytes included in the test. This test will provide a valuable clinical diagnostic and public health solution for detecting and differentiating SARS-CoV-2, influenza A and B, and RSV infections during the current respiratory virus season.

The results of a prospective study comparing ultrasound, intra-arterial digital subtraction angiography, and magnetic resonance angiography in the assessment of the degree of extracranial internal carotid artery stenosis are reported in patients with symptoms of recent carotid territory ischaemia. A total of 70 patients and 137 vessels were examined by all three techniques. The results obtained by each technique were reported blind. The mean difference (SD) for the comparison of magnetic resonance angiography and digital subtraction angiography was -0-7 (14)%, for ultrasound and digital subtraction angiography 3-1 (15)%, and for magnetic resonance angiography and ultrasound -3-8 (15)

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was first identified in December 2019 and has quickly become a worldwide pandemic. In response, many diagnostic manufacturers have developed molecular assays for SARS-CoV-2 under the Food and Drug Administration (FDA) Emergency Use Authorization (EUA) pathway. This study compared 3 of these assays: the Hologic Panther Fusion SARS-CoV-2 assay (Fusion), the Hologic Aptima SARS-CoV-2 assay (Aptima) and the BioFire Defense COVID-19 test (BioFire), to determine analytical and clinical performance, as well as workflow. All 3 assays showed a similar limit of detection (LOD) using inactivated virus, with 100% detection ranging from 500-1,000 genome equivalents/ml, whereas use of a quantified RNA transcript standard showed the same trend, but had values ranging from 62.5 to 125 copies/ml, confirming variability in absolute quantification of reference standards. The clinical correlation found that the Fusion and BioFire assays had a positive percent agreement (PPA) of 98.7%, followed by the Aptima assay at 94.7% when compared to the consensus result. All three assays exhibited 100% negative percent agreement (NPA). Analysis of discordant results revealed that all 4 samples missed by the Aptima assay had Ct values >37 on the Fusion assay. In conclusion, while all three assays showed similar relative LODs, we showed differences in absolute LODs depending on which standard was employed. In addition, the Fusion and BioFire assays showed better clinical performance, while the Aptima assay showed a modest decrease in overall PPA. These findings should be kept in mind when making platform testing decisions.

Prolonged hemiparetic migraine aura can cause diagnostic confusion and be mistaken for ischaemic stroke occurring during the course of a migraine--'migrainous infarction'. We report a case of prolonged hemiparesis occurring during the course of a migraine attack. Though initially confused with migrainous infarction, we suggest with sequential magnetic resonance imaging, magnetic resonance angiography, diffusion, perfusion images and magnetic resonance spectroscopy that the hemiplegia was not of vascular origin and that the patient had sporadic hemiplegic migraine. We hypothesize that the mechanisms of sporadic hemiplegic migraine probably lie at a cellular level, similiar to familial hemiplegic migraine.

Trigeminal neuralgia and sensory disturbance is common in multiple sclerosis (MS). Recent literature suggests that signal abnormalities in the cisternal trigeminal nerve and pontine root entry zone are seen in approximately 3% of MS patients, using conventional diagnostic MRI. The objective of this study was to determine the prevalence of trigeminal lesions using high-resolution MRI at 3T. Forty-seven patients with clinically definite MS, chosen at random from the outpatient population of a neuroscience centre underwent MRI on a Siemens 3T Trio machine. Three 3D sequences of T2 TSE (turbo spin echo), T2 FLAIR (fluid attenuated inversion recovery) and T1 IR (inversion recovery) were acquired in the coronal plane. The sequences were of contiguous 1 mm slices with in-plane resolution of up to 0.5 mm by 0.5 mm. Images were read by both a neurologist and a neuroradiologist. Any clinical history of trigeminal symptoms was determined for all subjects. The results showed that 11 patients (23%) had high signal in the trigeminal root entry zone and either the trans-cisternal nerve or pontine nucleus; example images are given. MRI changes did not correspond to clinical symptoms (chi square probability 1.000). The study concludes that high-resolution MRI at 3T yielded a high prevalence of detectable trigeminal abnormality in the MS sample studied. MRI involvement did not correspond to trigeminal symptoms.

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