Clinical features of COVID-19-related encephalitis: comparison with the features of herpes virus encephalitis and autoimmune encephalitis.

INTRODUCTION: Identifying coronavirus disease 2019 (COVID-19)-related encephalitis without clear etiological evidence is clinically challenging. The distinctions between this condition and other prevalent encephalitis types remain unknown. Therefore, we aimed to explore the similarities and differences in the clinical characteristics of COVID-19-related encephalitis and other encephalitis types. METHODS: Adult patients with encephalitis admitted to the neurology department at Xuanwu Hospital were enrolled and categorized into the following six groups based on the results of metagenomic next-generation sequencing and autoimmune antibody detection in cerebrospinal fluid (CSF): COVID-19-related encephalitis (n = 36), herpes simplex virus type 1 encephalitis (HSV-1 encephalitis; n = 28), human herpesvirus 3 encephalitis (HHV-3 encephalitis; n = 10), NMDAR-antibody encephalitis (n = 18), LGI1-antibody encephalitis (n = 12), and GABAB-antibody encephalitis (n = 8). RESULTS: The predominant characteristics of COVID-19-related encephalitis include a low incidence of seizures (38.9%), cognitive defects (30.6%), and meningeal irritation signs (8.3%). Compared with HSV-1 and HHV-3 encephalitis, COVID-19-related encephalitis exhibited lower white blood cell count (2.5 count/mm3), protein (32.2 mg/dL), and immunoglobulin M, G, and A levels (0.09, 3.2, and 0.46 mg/dL, respectively) in the CSF tests. Abnormal imaging findings were present in only 36.1% of COVID-19-related encephalitis cases, mostly showing diffuse inflammation scattered in various parts, which differed from HSV-1 encephalitis. Additionally, COVID-19-related encephalitis exhibited significant differences in clinical symptoms and CSF white blood cell counts compared with NMDAR-antibody encephalitis; however, it showed limited differences compared with LGI1-antibody and GABAB-antibody encephalitis. DISCUSSION: COVID-19-related encephalitis and herpes virus or autoimmune encephalitis differ clinically. Symptoms and auxiliary examinations can be used as distinguishing tools.

[Sporadic Creutzfeldt-Jakob Disease With Slow Progression:Report of One Case].

Sporadic Creutzfeldt-Jakob disease(sCJD)is a prion-caused degenerative disease of the central nervous system,with the typical clinical manifestation of rapidly progressive dementia.The course of disease is less than 1 year in most patients and more than 2 years in only 2% to 3% patients.We reported a case of sCJD with expressive language disorder and slow progression in this paper.By summarizing the clinical manifestations and the electroencephalograhpy,MRI,and pathological features,we aimed to enrich the knowledge about the sCJD with slow progression.

Effect of P-glycoprotein Inhibition on the Penetration of Ceftriaxone Across the Blood-Brain Barrier.

Recent studies indicate that inhibition of the efflux transporter P-glycoprotein (P-gp) at the blood-brain barrier (BBB) may represent a putative strategy to increase the BBB penetration of several antibiotics. Therefore, the present study aimed to investigate the effect of P-gp inhibition on the transport of ceftriaxone (CFX) across the BBB. Blood and brain microdialysis in rats was used to monitor blood and brain unbound CFX concentrations following intravenous administration (50 mg/kg), with or without pretreatment with one of the P-gp inhibitors, cyclosporin A (6.25, 12.5, 25 mg/kg) or verapamil (5, 10, 20 mg/kg). An inhibitory effect was demonstrated by an increase in the ratio of unbound brain to unbound blood concentration (Kp.uu.brain) of CFX. The concentrations of CFX in blood and brain from 0 to 180 min after intravenous administration (CFX, 50 mg/kg) ranged from 3 to 40 µg/ml and 1 to 10 µg/ml, respectively. The Kp.uu.brain of CFX was 24.74 ± 1.34%. Pretreatment with cyclosporin A increased the brain concentration and the Kp.uu.brain of CFX in a dose-dependent manner. However, pretreatment with verapamil increased the brain concentration of CFX but not the Kp.uu.brain. The present data shows that CFX might be a substrate of P-gp efflux transporter at the BBB and P-gp inhibition might enhance the brain concentration of CFX. Future studies involving more selective P-gp inhibitors or knockout mouse models should be conducted to specifically elucidate the impact of P-gp inhibition on penetration of CFX across the BBB.

The relationship of leukoaraiosis, haemorrhagic transformation and prognosis at 3 months after intravenous thrombolysis in elderly patients aged ≥ 60 years with acute cerebral infarction.

BACKGROUD: As the elderly stroke population continues to increase, we will have to confront greater challenges regarding how to choose suitable patients to reduce thrombolysis-related bleeding events and accurately judge their prognosis. Therefore, we evaluated the relationship among leukoaraiosis (LA), haemorrhagic transformation (HT) and the prognosis at 3 months after intravenous (IV) thrombolysis in elderly patients aged ≥ 60 years with acute cerebral infarction (ACI). METHODS: We prospectively and consecutively chose 125 elderly patients aged ≥ 60 years with ACI who could accept and be suitable for IV recombinant tissue plasminogen activator (rtPA) after excluding 6 cases. Brain computed tomography(CT) was used to assess LA by using the modified Van Swieten scale (mVSS) before treatment and the modified Rankin scale (mRS) to appraise prognosis at 3 months after IV rtPA. Binary logistic regression was used to analyse the predictors of HT and the prognosis of ACI. RESULTS: Our data indicated that by brain CT, 26.4% of all patients showed severe LA, and the rate of HT and symptomatic intracranial haemorrhage (sICH) were 12.0% and 9.6%, respectively. Severe LA was evidently associated with HT (odds ratio [OR] 3.272, 95% confidence interval [CI] 1.010-10.598, P = 0.048) rather sICH (P > 0.05). Moreover, we also found that severe LA was associated with poor functional prognosis (OR 5.266, 95% CI 1.592-17.419, P = 0.006). CONCLUSION: Our results showed that LA was associated with HT and adverse clinical prognosis rather sICH after IV rtPA in elderly patients aged ≥60 years with ACI. Although LA may increase the risk of bleeding but not fatal haemorrhage after IV thrombolysis, therefore, we should actively select an appropriate elderly population for thrombolytic treatment and have reasonable judgments on the outcomes.

Sporadic Creutzfeldt-Jakob Disease: A Retrospective Analysis of 104 Cases.

BACKGROUND: Sporadic Creutzfeldt-Jakob disease (sCJD) is an extremely rare fatal and infectious neurodegenerative brain disorder characterized by rapidly progressive dementia, cerebellar ataxia, and visual disturbances. This article summarizes the retrospective analysis of 104 sCJD patients in the First Medical Center of Chinese PLA General Hospital from 2003 to 2019. METHODS: A retrospective analysis of the medical records of the 104 patients diagnosed with sCJD was performed from the aspects of demographic data, clinical manifestations, laboratory examinations, cerebrospinal fluid analysis, electroencephalograms (EEGs), diffusion-weighted imaging (DWI) scans, positron emission tomography (PET) scans, and prion protein gene mutations. RESULTS: In the 104 sCJD patients, pathological evidence of a spongiform change was found in 11 patients, while the remaining 93 patients were probable sCJD. The 104 patients included 57 males and 47 females, with the age of onset ranging from 29 to 82 (mean: 58, median: 60) years. The time from disease onset to death ranged from 1 to 36 months. Most of the patients died 7-12 months after the onset of sCJD. In most patients, rapidly progressive dementia appeared as the initial symptom, followed by cerebellar ataxia, visual disturbances, and neurobehavioral disorders. Most patients' DWI images showed symmetric or asymmetric hyperintensity in the cortex. In terms of EEGs, 38.2% of the patients had periodic sharp wave complexes. The sensitivity of 14-3-3 protein detection was 34.1%. The brain PET scans of 50 patients with sCJD presented 96% sensitivity for the diagnosis of sCJD. CONCLUSIONS: This study indicated that sCJD occurred at an early age in patients in China. The sensitivity of 14-3-3 protein detection was significantly low, but brain PET was highly sensitive in the diagnosis of sCJD.

Evaluation of Next-Generation Sequencing for the Diagnosis of Infections of the Central Nervous System Caused by the Neurotropic Herpes Viruses: A Pilot Study.

BACKGROUND: There are sparse and limited studies on small sample size reporting the application of next-generation sequencing (NGS) in the detection of central nervous system (CNS) viral infections. We assessed the diagnostic performance of NGS of cerebrospinal fluid (CSF) for predicting viral infections of the CNS caused by the neurotropic herpes viruses in a pilot population. MATERIALS AND METHODS: We prospectively collected CSF samples from 24 patients with CNS viral infection from April 2017 to October 2018. Of the 24 patients, 19 patients were infected with herpes simplex virus 1 (HSV-1), 1 patient with HSV-2, and 4 patients with varicella-zoster virus (VZV). All CSF samples were screened for viral DNA using NGS technologies to detect viral CNS infections. RESULTS: Of the 24 patients with confirmed viral CNS infection caused by the neurotropic herpes viruses, 10 (10/24, 41.67%) patients exhibited positive NGS results. With the help of NGS, HSV-1 DNA was detected in the CSF of 6 patients (6/19; 31.58%). HSV-2 DNA was detected in 1 patient (1/1; 100%) and VZV DNA was detected in 3 patients (3/4; 75%). The positive rate of virus detected by NGS decreased with time. The positive rates of NGS of CSF in the first, second, and third weeks were 54.5% (6/11), 44.4% (4/9), and 0% (0/4), respectively. CONCLUSIONS: NGS method is a promising pathogen detection tool for identifying viral CNS infections. It should be recommended to sequence viral DNA of CSF in the early stage of CNS viral infections.

Neurobrucellosis.

PURPOSE: Neurobrucellosis (NB) is a rare complication of brucellosis. NB presents with avariety of clinical manifestations, and the symptoms are always atypical. Our aim was to analyze the demographic characteristics, clinical manifestations, laboratory findings, imaging findings, treatments and outcomes of patients with NB. MATERIAL AND METHOD: We retrospectively reviewed the data from 17 patients with NB hospitalized at the Chinese People's Liberation Army General Hospital between 1 January 2005 and 31 October 2016. RESULTS: The following symptoms were recorded: 10/17 (59%) patients had fever, and 9/17 (53%) patients had a disorder affecting urination and defecation. Involvement of the cranial nerves was documented in 12/17 (71%) patients. The positivity rates of the tests were as follows: serum standard tube agglutination (STA), 15/17 (88.2%); cerebrospinal fluid STA, 10/17 (59%). The radiologic findings were categorized into four types: normal, white matter changes, vascular insult and inflammatory changes. Patients were treated with different combinations of rifampicin, doxycycline, ceftriaxone sodium and sulphamethoxazole for a total of six months. Two (12%) patients deteriorated, and two (12%) patients were lost to follow-up. The remaining patients (76%) were cured, but sequelae occurred in six patients. CONCLUSIONS: NB should be kept in mind in patients with autonomic dysfunction, especially disorders of urination and defecation. Hearing loss due to vestibulocochlear nerve injury seems to be typical for NB. The high incidence of sequelae may be related to a long disease course and the involvement of the central nervous system. Early detection, diagnosis and treatment could decrease mortality and sequelae.

Effect of Efflux Transporter Inhibition on the Distribution of Fluconazole in the Rat Brain.

Multidrug resistance-associated proteins (MRPs) and organic anion transporters (OATs) are expressed on the blood-brain barrier (BBB) and blood-cerebrospinal fluid barrier (BCSFB), preventing the entry of or the pumping out of numerous molecules. Fluconazole is widely used to treat fungal meningoencephalitis. The effect of these transporters on the distribution of fluconazole in the brain is unclear. We used microdialysis to compare the distribution of fluconazole in the rat brain with and without co-administration of probenecid, a MRP and OAT inhibitor. Additionally, we also observed the difference in fluconazole distribution between the two barriers. The results showed that probenecid increased the penetration of fluconazole into the BBB but did not alter the penetration of fluconazole into the BCSFB of rats. The penetration of the BBB and BCSFB by fluconazole did not statistically differ according to physiological condition. These results demonstrate that transporters that can be inhibited by probenecid may be involved in fluconazole resistance at the BBB and provide a laboratory basis for predicting brain extracellular fluid (ECF) concentration using the cerebrospinal fluid (CSF) concentration of fluconazole.

Cerebral aspergillosis: a retrospective analysis of eight cases.

PURPOSE: Aspergillosis of the central nervous system is very rare. However with recent increases in the use of immunosuppressive agents and antibiotics, its incidence is increasing. We evaluated the demographics, clinical manifestations, laboratory findings, diagnosis, underlying conditions, treatment regimens and outcomes of patients with cerebral aspergillosis (CA). METHODS: We retrospectively reviewed data from eight patients with CA hospitalized at a Chinese general hospital from 1 January 2005 to 30 September 2015. RESULTS: Common clinical manifestations included headache and cranial nerve involvement. Four patients underwent biopsy and were pathologically diagnosed with Aspergillus hyphae. One patient was proved to have Aspergillus infection via autopsy. One patient had positive cerebrospinal fluid fungal cultures. The lesion locations were: the cavernous sinus (n = 5, 62.5%), frontal lobe (n = 1, 12.5%), temporosphenoid lobe (n = 1, 12.5%) and cerebellum (n = 1, 12.5%). At the end of follow-up, three patients were cured and five patients had died (mortality rate, 62.5%). CONCLUSIONS: Most patients with CA had no significant immunosuppression-related conditions in our study. Aspergillus spp. can infect the central nervous system through several pathways and CA has an atypical clinical manifestation. The use of local tissue puncture, surgery or other invasive means to obtain diseased tissue containing higher levels of Aspergillus, followed by culture or histological examination, can contribute to an early diagnosis of CA and timely therapeutic intervention. The prognosis of CA is poor, but early and adequate use of antifungal drugs with high transfer across the blood-brain barrier and radical surgery to remove lesions can improve the survival rate.

Incidence and risk factors of pleural effusions in patients with POEMS syndrome.

Information regarding the characteristics of pleural effusions in patients with POEMS syndrome is limited. The aim of this study was to describe the incidence and risk factors of pleural effusions in patients with POEMS syndrome and characterize the pleural fluid biochemistry in those patients. A retrospective review of 96 patients with POEMS syndrome was conducted. The patients were divided into groups with and without pleural effusions. The clinical data were obtained from medical charts. Risk factors were studied with univariate and multivariate analysis. The median age at the time of diagnosis of POEMS syndrome was 45.1 years, and the median disease duration was 30.4 months. Pleural effusions were detected in 41 (42.7%) of the 96 patients. Increased serum vascular endothelial growth factor (VEGF), complement component 3 (C3), Lambda light chain, tumour necrosis factor (TNF)-α, interleukin (IL)-6 levels and low albumin as well as cardiac disease were found to be significantly correlated with pleural effusions. By multivariate logistic regression, independent risk factors for pleural effusions in POEMS syndrome were VEGF [odds ratio (OR): 2.46, 95% confidence interval (CI): 1.720-3.414, p = 0.01], TNF-α (OR: 3.64, 95% CI: 1.073-4.338, p = 0.04) and C3 (OR: 3.77, 95% CI: 1.225-3.591, p = 0.02) levels. Pleural effusions are the most common thoracic involvement findings in patients with POEMS syndrome, and all the pleural fluids are exudates. Serum VEGF, TNF-α and C3 levels are identified as important risk factors for presence of pleural effusions in POEMS syndrome.

Characteristics of CADASIL in Chinese mainland patients.

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) has been reported in many geographical regions. However, relatively few reports about CADASIL in Chinese were reported. MATERIALS AND METHODS: We retrospectively collected and analyzed clinical characteristics, magnetic resonance (MRI) features and genetic data of 52 Chinese mainland CADASIL patients. RESULTS: Mean age of onset was 42.43 years. The primary clinical manifestations included: Ischemic stroke/transient ischemic attack (62.5%), primary intracerebral hemorrhage (25%), vertigo (25%), migraine (39.58%), dementia (18.75%) and emotional disturbance (20.83%). The most frequently observed MRI abnormalities were hyperintensity in the cerebral white matter on T2-weighted images and multiple infarcts, high-signal lesions on T2 images in anterior temporal lobes and external capsule were uncommon. The highest mutation frequency was in exon regions, 4 and 3, followed by exon 11. Granular osmiophilic material (GOM) was identified in 66.67% of the cases examined with biopsy. CONCLUSIONS: Most characteristics of Chinese mainland CADASIL patients are similar to those of CADASIL patients living in other regions. However, the prevalence of primary intracerebral hemorrhage and vertigo is much higher in Chinese mainland CADASIL patients. Significant leukoaraiosis in anterior temporal poles on T2-weighted image are uncommon. Exons 3 and 4 are the mutation hotspots.

The ATP-Binding Cassette Transporter-Mediated Efflux Transport of Ganciclovir at the Blood-Brain Barrier.

BACKGROUND AND OBJECTIVE: Recent studies have highlighted the key role of the ATP-binding cassette (ABC) transporters, including the P-glycoprotein (P-gp), the breast cancer resistance protein (BCRP), and the multi-drug resistance protein 4 (MRP4) in limiting the brain distribution of several antiviral agents. In this study, we investigated whether the inhibition of these transporters increases the permeability of the blood-brain barrier (BBB) to ganciclovir. METHODS: A microdialysis and high-performance liquid chromatographic method was developed to monitor the concentrations of unbound ganciclovir in the brain interstitial fluid and plasma, with and without the administration of ABC transporter inhibitors. Pharmacokinetic parameters, including the area under the plasma concentration-time curve from time 0 to time of the last measurable analyte concentration (AUC0-t,plasma), the area under the brain interstitial fluid concentration-time curve from time 0 to time of the last measurable analyte concentration (AUC0-t,brain), and the unbound brain-to-plasma concentration ratio (Kp,uu,brain) were calculated. RESULTS: The mean AUC0-t,plasma, AUC0-t,brain, and Kp,uu,brain in rats who received ganciclovir (30 mg/kg, intraperitoneal) alone were 1090 min·µg/mL, 150 min·µg/mL, and 14%, respectively. After the administration of tariquidar (inhibitor of P-gp), Ko143 (inhibitor of BCRP), or MK-571 (inhibitor of MRP4), the Kp,uu,brain of ganciclovir increased to 31 ± 2.1%, 26 ± 1.3%, and 32 ± 2.0%, respectively. CONCLUSIONS: The findings of this study suggest that ABC transporters P-gp, BCRP, and MRP4 mediate the efflux of ganciclovir at the BBB and that the inhibition of these transporters facilitates the penetration of the BBB by ganciclovir.

Evaluation of metagenomic and pathogen-targeted next-generation sequencing for diagnosis of meningitis and encephalitis in adults: A multicenter prospective observational cohort study in China.

BACKGROUND: Next-generation sequencing (NGS) might aid in the identification of causal pathogens. However, the optimal approaches applied to cerebrospinal fluid (CSF) for detection are unclear, and studies evaluating the application of different NGS workflows for the diagnosis of intracranial infections are limited. METHODS: In this multicenter, prospective observational cohort study, we described the diagnostic efficacy of pathogen-targeted NGS (ptNGS) and metagenomic NGS (mNGS) compared to that of composite microbiologic assays, for infectious meningitis/encephalitis (M/E). RESULTS: In total, 152 patients diagnosed with clinically suspected M/E at four tertiary hospitals were enrolled; ptNGS and mNGS were used in parallel for pathogen detection in CSF. Among the 89 patients who were diagnosed with definite infectious M/E, 57 and 39 patients had causal microbial detection via ptNGS and mNGS, respectively. The overall accuracy of ptNGS was 65.1%, with a positive percent agreement (PPA) of 64% and a negative percent agreement (NPA) of 66.7%; and the overall accuracy of mNGS was 47.4%, with a PPA of 43.8% and an NPA of 52.4% after discrepancy analysis. There was a significant difference in the detection efficiency between these two methods both for PPA (sensitivity) and overall accuracy for pathogen detection (P < 0.05). CONCLUSIONS: NGS tests have provided new information in addition to conventional microbiologic tests. ptNGS seems to have superior performance over mNGS for common causative pathogen detection in CSF for infectious M/E.

Multiple drug transporters contribute to the brain transfer of levofloxacin.

AIMS: The aim of this study was to assess the influence of the major transporters at blood-brain barrier and blood-cerebrospinal fluid barrier on levofloxacin (LVFX) pharmacokinetics in rat. To explore the different effects of transporters on drug concentrations in cerebrospinal fluid (CSF) and brain extracellular fluid (ECF). METHODS: High-performance liquid chromatography coupled with microdialysis was used to continuously and synchronously measure unbound concentrations of LVFX in rat blood, hippocampal ECF, and lateral ventricle CSF for comprehensive characterization of brain pharmacokinetics. The role of transporters in the brain efflux mechanism of LVFX was analyzed in the absence and presence of various transporter inhibitors. RESULTS: Following LVFX (50 mg/kg) administration, the unbound partition coefficient of LVFX in brain ECF and CSF (Kp,uu,ECF and Kp,uu,CSF ) were 34.0 ± 1.7% and 41.2 ± 2.4%, respectively. When probenecid was coadministered with LVFX, the AUC and the mean residence time (MRT) in rat blood increased significantly (p < 0.05). After MK571 intervention, 1.35-fold and 1.16-fold increases in Kp,uu,ECF and Kp,uu,CSF were observed, respectively (p < 0.05). Treatment with Ko143 increased the levels of LVFX in brain ECF. The difference in LVFX concentration in brain ECF and CSF was <3-fold with or without treatment with transporter inhibitors. CONCLUSION: Efflux of LVFX from the central nervous system (CNS) involves multidrug resistance-associated proteins (MRPs), breast cancer resistance protein (BCRP), and organic anion transporters (OATs). MRPs play an important role in mediating the brain/CSF-to-blood efflux of LVFX. LVFX concentrations in CSF can be used as a surrogate to predict the concentrations inside brain parenchyma.

Clinical Characteristics and Treatment of Listeria monocytogenes Infections in the Central Nervous System.

Purpose: Listeria monocytogenes infections are rare in the central nervous system (CNS) and frequently difficult-to-diagnose. Our goal is to assess CNS listeriosis patients' clinical characteristics, diagnosis, treatment, and prognosis. Patients and Methods: Patients with CNS listeriosis admitted to the Department of neurology, the first medical center of the Chinese PLA general hospital, were enrolled in this study from March 2018 to August 2022. Results: This study analyzed eight adults, including five males and three females. The average age of onset was (50.25 ± 11.52) years. The clinical manifestations included fever, headache, altered mental status, vomiting, seizures, neck rigidity, hemiplegia and cranial nerve palsies. Cerebrospinal fluid (CSF) tests revealed intracranial hypertension, elevated cell count and protein concentration, and decreased glucose levels. The positive rates of blood and CSF culture were 40% and 28.57%, respectively. All patients underwent CSF metagenomic next-generation sequencing (mNGS), with a 100% positive rate and the specific read number 12-20394. Magnetic resonance imaging (MRI) exhibited leptomeningitis, meningoencephalitis, and brain abscess, and no specific changes were discovered in two patients. All patients received antibiotic treatment, seven were cured, and one died. Conclusion: Monitoring the proportion of monocytes in blood and mNGS results of CSF can play a crucial role in diagnosing pathogens. Early and sufficient application of two to three sensitive antibiotics with a BBB permeability of 20-30% for at least 2-3 months can significantly improve CNS listeriosis prognosis.

Acyclovir Brain Disposition: Interactions with P-gp, Bcrp, Mrp2, and Oat3 at the Blood-Brain Barrier.

BACKGROUND AND OBJECTIVE: Acyclovir is effective in treating herpes simplex virus infections of the central nervous system. The purpose of this study was to investigate the interactions between acyclovir and the efflux pumps P-glycoprotein (P-gp), breast cancer resistance protein (Bcrp), multidrug resistance protein 2 (Mrp2), and organic anion transporter 3 (Oat3) at the blood-brain barrier (BBB). METHODS: Acyclovir concentrations in the blood and brain were evaluated by microdialysis and high-performance liquid chromatography. Acyclovir pharmacokinetic parameters, including the area under the unbound blood concentration-time curve (AUCu,blood), the area under the unbound brain concentration-time curve (AUCu,brain), and the ratio of AUCu,brain to AUCu,blood (Kp.uu.brain), were evaluated in the presence and absence of elacridar (P-gp/Bcrp inhibitor, 7.5 mg/kg), tariquidar (P-gp/Bcrp inhibitor, 7.5 mg/kg), MK571 (Mrp2 inhibitor, 7.5 mg/kg), cyclosporine (P-gp/Bcrp/Mrp2 inhibitor, 25 mg/kg), and probenecid (Oat3 inhibitor, 50 mg/kg). RESULTS: The average AUCu,blood, AUCu,brain, and Kp.uu.brain in rats who received acyclovir (25 mg/kg, intravenous) alone were 1377.7 min · µg/ml, 435.4 min · µg/ml, and 31.6%, respectively. Probenecid drastically increased the AUCu,blood of acyclovir 1.73-fold, whereas coadministration with elacridar, tariquidar, MK571, and cyclosporine did not alter the blood pharmacokinetic parameters of acyclovir. Elacridar, tariquidar, MK571, cyclosporine, and probenecid significantly increased the AUCu,brain of acyclovir 1.51-, 1.54-, 1.47-, 1.95-, and 2.34-fold, respectively. Additionally, the Kp.uu.brain of acyclovir markedly increased 1.48-, 1.63-, 1.39-, 1.90-, and 1.35-fold following elacridar, tariquidar, MK571, cyclosporine, and probenecid administration, respectively. CONCLUSION: The present study demonstrated that P-gp, Bcrp, Mrp2, and Oat3 inhibition increased the penetration of acyclovir across the BBB, supporting the hypothesis that these efflux pumps restrict the distribution of acyclovir in the brain.

Creutzfeldt-Jakob disease associated with a T188K homozygous mutation in the prion protein gene: a case report and review of the literature.

Genetic Creutzfeldt-Jakob disease (gCJD) is a prion disease caused by mutations in the prion protein gene (PRNP). It has an autosomal dominant inheritance, so gCJD with homozygous mutations is extremely rare, and the influence of homozygous mutations on the gCJD phenotype is unknown. We describe the clinical and laboratory features of a patient with a PRNP T188K homozygous mutation and perform a literature review of gCJD cases with PRNP homozygous mutations. The patient was presented with cerebellum symptoms, cognitive decline and visual disturbances. Auxiliary examinations revealed restricted diffusion in magnetic resonance imaging and glucose hypometabolism on 18Fluorodeoxyglucose-positron emission tomography. No periodic sharp wave complexes were detected in electroencephalography, and the cerebrospinal fluid 14-3-3 protein was negative. PRNP sequencing revealed the presence of a homozygous T188K variant. The patient died 15 months after disease onset. A literature review revealed PRNP V203I, E200K and E200D as the only three mutations reported as homozygous in gCJD. To the best of our knowledge, this is the first report of a gCJD patient with a PRNP T188K homozygous mutation. Although the clinical manifestations of our patient were similar to those with PRNP T188K heterozygous mutations, she presented with a slightly earlier onset and had a longer survival time. This is consistent with previous observations from patients with PRNP V203I and E200K homozygous mutations. Further studies are essential to clarify the influence of homozygous mutations on the gCJD phenotype.

Lower motor neuron involvement in patients with neuromyelitis optica spectrum disorders.

BACKGROUND: Involvement of the central gray matter of spinal cord is a characteristic magnetic resonance imaging (MRI) feature of aquaporin-4-immunoglobulin G antibodies (AQP4-IgG) positive neuromyelitis optica spectrum disorders (NMOSD). However, there has been no systemic electrophysiological study investigating the frequency of lower motor neuron involvement in NMOSD patients. METHODS: We retrospectively reviewed a cohort of 59 NMOSD patients with results of concentric needle electromyography (EMG) and nerve conduction studies (NCS) that were admitted to the Department of Neurology of Chinese PLA General Hospital between January 2016 and December 2019. RESULTS: Acute and/or chronic denervation was found in 22.0% (13/59) of the NMOSD patients by EMG. Peripheral or cranial neuropathy indicated by abnormal NCS changes was found in 11.9% (7/59) of the NMOSD patients. Denervation indicated by EMG that can be accounted for by abnormal NCS was found in 6.8% (4/59) of the NMOSD patients, while 3.4% (2/59) of the NMOSD patients had NCS abnormality without denervation indicated by EMG. Accordingly, 9 of the 59 NMOSD patients (15.3%) had lower motor neuron involvement, and moreover, 6.8% (4/59) of the NMOSD patients had corresponding spinal cord or brainstem lesions on MRI. CONCLUSION: Not uncommon lower motor neuron involvement exists in NMOSD patients, so needle EMG and NCS studies should be performed in NMOSD patients with suspected lower motor neuron involvement.

Proposal of new diagnostic criteria for fatal familial insomnia.

BACKGROUND: The understanding of fatal familial insomnia (FFI), a rare neurodegenerative autosomal dominant prion disease, has improved in recent years as more cases were reported. This work aimed to propose new diagnostic criteria for FFI with optimal sensitivity, specificity, and likelihood ratio. METHODS: An international group of experts was established and 128 genetically confirmed FFI cases and 281 non-FFI prion disease controls are enrolled in the validation process. The new criteria were proposed based on the following steps with two-round expert consultation: (1) Validation of the 2018 FFI criteria. (2) Diagnostic item selection according to statistical analysis and expert consensus. (3) Validation of the new criteria. RESULTS: The 2018 criteria for possible FFI had a sensitivity of 90.6%, a specificity of 83.3%, with a positive likelihood ratio (PLR) of 5.43, and a negative likelihood ratio (NLR) of 0.11; and the probable FFI criteria had a sensitivity of 83.6%, specificity of 92.9%, with a PLR of 11.77, and a NLR of 0.18. The new criteria included more specific and/or common clinical features, two exclusion items, and summarized a precise and flexible diagnostic hierarchy. The new criteria for possible FFI had therefore reached a better sensitivity and specificity (92.2% and 96.1%, respectively), a PLR of 23.64 and a NLR of 0.08, whereas the probable FFI criteria showed a sensitivity of 90.6%, a specificity of 98.2%, with a PLR of 50.33 and a NLR of 0.095. CONCLUSIONS: We propose new clinical diagnostic criteria for FFI, for a better refining of the clinical hallmarks of the disease that ultimately would help an early recognition of FFI and a better differentiation from other prion diseases.

CSF and serum hCG in patients without gestational and neoplastic hCG-secretion.

BACKGROUND: The measurement of human chorionic gonadotropin (hCG) in cerebrospinal fluid (CSF) is important for the diagnosis of intracranial or intraspinal trophoblastic tumours. The current study was performed to establish reference values for hCG in CSF and to explore the relationship of CSF hCG and serum hCG in patients who are not pregnant or do not have trophoblastic tumours. MATERIAL AND METHODS: CSF samples were obtained from 369 inpatients admitted because of various neurological diseases, excluding pregnancy, trophoblastic tumours and other malignant tumours. In 271 of the 369 patients, paired samples of CSF and serum were obtained. Both CSF hCG and serum hCG were measured. The 97.5th percentile and maximum value of CSF hCG were obtained. The CSF hCG and serum hCG concentrations in each of the 271 paired samples were compared. RESULTS: The 97.5th percentile and maximum value of CSF hCG concentration for overall participants were 1.00 and 5.00 IU/L, respectively. The CSF hCG concentration was found to be higher than the simultaneous serum hCG concentration in 81.9% (222/271) of the participants. CONCLUSIONS: The reference value determined in this study of CSF hCG in men is significantly lower than that usually used in clinical practice. A CSF hCG concentration higher than the simultaneous serum hCG concentration but lower than the upper reference limit does not necessarily suggest abnormal intrathecal hCG-secretion.