An unexpected case of acute intermittent porphyria

Acute Intermittent Porphyria (AIP) can be a challenging diagnosis to make, due to its rarity in actual practice and presenting symptoms often being attributed to more common conditions. This is particularly the case, since many patients will likely present to acute and general hospitals where the diagnosis may often not be considered. However, it remains pivotal to diagnose the condition as early as possible to prevent significant morbidity and even death. Here we present an unexpected case of AIP, illustrating the diagnostic delay that is commonly seen with the condition and yet emphasise the importance of its detection to commence urgent treatment.

LGI1 Encephalitis and IgG4-Related Disease: Rare Conditions Collide

OBJECTIVES

Leucine-rich glioma-inactivated 1 (LGI1) encephalitis and IgG4-related disease (IgG4RD) have traditionally been regarded as 2 distinct disease entities.

METHODS

We detail the presentation, investigations, and management of a patient who showed typical signs and symptoms of LGI1 encephalitis and also found to possess pancreatic changes and a serum profile in keeping with IgG4RD.

RESULTS

Serum and CSF analyses at presentation showed a significant hyponatraemia (117 mmol/L), elevated IgG4 concentration (1.73 g/L), and the presence of LGI1 antibodies. MRI revealed symmetrical diffuse T2-weighted hyperintensity and mild swelling throughout both medial temporal lobes. CT of the chest, abdomen and pelvis revealed an edematous, bulky pancreas with loss of lobulation, typical for IgG4RD. A glucocorticoid weaning regimen was commenced, facilitated by 2 rituximab infusions, with the patient showing an effective treatment response. HLA testing confirmed the presence of HLA DRB1 and HLA DQB1 risk alleles.

DISCUSSION

This case suggests that there may be shared mechanisms between LGI1 encephalitis and IgG4RD, supported by common risk HLA associations and treatment strategies/responses. To our knowledge, this represents the first instance that LGI1 encephalitis and IgG4RD have been reported in the same patient and emphasizes the continued development of our understanding of the wide range of IgG4-mediated conditions.

Phenotypic effect of GBA1 variants in individuals with and without Parkinson's disease: The RAPSODI study

BACKGROUND

Variants in the GBA1 gene cause the lysosomal storage disorder Gaucher disease (GD). They are also risk factors for Parkinson's disease (PD), and modify the expression of the PD phenotype. The penetrance of GBA1 variants in PD is incomplete, and the ability to determine who among GBA1 variant carriers are at higher risk of developing PD, would represent an advantage for prognostic and trial design purposes.

OBJECTIVES

To compare the motor and non-motor phenotype of GBA1 carriers and non-carriers.

METHODS

We present the cross-sectional results of the baseline assessment from the RAPSODI study, an online assessment tool for PD patients and GBA1 variant carriers. The assessment includes clinically validated questionnaires, a tap-test, the University of Pennsyllvania Smell Identification Test and cognitive tests. Additional, homogeneous data from the PREDICT-PD cohort were included.

RESULTS

A total of 379 participants completed all parts of the RAPSODI assessment (89 GBA1-negative controls, 169 GBA1-negative PD, 47 GBA1-positive PD, 47 non-affected GBA1 carriers, 27 GD). Eighty-six participants were recruited through PREDICT-PD (43 non-affected GBA1 carriers and 43 GBA1-negative controls). GBA1-positive PD patients showed worse performance in visual cognitive tasks and olfaction compared to GBA1-negative PD patients. No differences were detected between non-affected GBA1 carriers carriers and GBA1-negative controls. No phenotypic differences were observed between any of the non-PD groups.

CONCLUSIONS

Our results support previous evidence that GBA1-positive PD has a specific phenotype with more severe non-motor symptoms. However, we did not reproduce previous findings of more frequent prodromal PD signs in non-affected GBA1 carriers.

Mapping a network for tics in Tourette syndrome using causal lesions and structural alterations

Tics are sudden stereotyped movements or vocalizations. Cases of lesion-induced tics are invaluable, allowing for causal links between symptoms and brain structures. While a lesion network for tics has recently been identified, the degree to which this network translates to Tourette syndrome has not been fully elucidated. This is important given that patients with Tourette syndrome make up a large portion of tic cases; therefore, existing and future treatments should apply to these patients. The aim of this study was to first localize a causal network for tics from lesion-induced cases and then refine and validate this network in patients with Tourette syndrome. We independently performed 'lesion network mapping' using a large normative functional connectome (n = 1000) to isolate a brain network commonly connected to lesions causing tics (n = 19) identified through a systematic search. The specificity of this network to tics was assessed through comparison to lesions causing other movement disorders. Using structural brain coordinates from prior neuroimaging studies (n = 7), we then derived a neural network for Tourette syndrome. This was done using standard anatomical likelihood estimation meta-analysis and a novel method termed 'coordinate network mapping', which uses the same coordinates, yet maps their connectivity using the aforementioned functional connectome. Conjunction analysis was used to refine the network for lesion-induced tics to Tourette syndrome by identifying regions common to both lesion and structural networks. We then tested whether connectivity from this common network is abnormal in a separate resting-state functional connectivity MRI data set from idiopathic Tourette syndrome patients (n = 21) and healthy controls (n = 25). Results showed that lesions causing tics were distributed throughout the brain; however, consistent with a recent study, these were part of a common network with predominant basal ganglia connectivity. Using conjunction analysis, coordinate network mapping findings refined the lesion network to the posterior putamen, caudate nucleus, globus pallidus externus (positive connectivity) and precuneus (negative connectivity). Functional connectivity from this positive network to frontal and cingulate regions was abnormal in patients with idiopathic Tourette syndrome. These findings identify a network derived from lesion-induced and idiopathic data, providing insight into the pathophysiology of tics in Tourette syndrome. Connectivity to our cortical cluster in the precuneus offers an exciting opportunity for non-invasive brain stimulation protocols.

Biopsy-proven fungal pyelonephritis complicating delayed graft function in a renal transplant patient

Delayed graft function (DGF) is a common phenomenon following renal transplantation, which can be due to several factors. A rare cause includes invasive fungal infections, which can often be a challenge to diagnose. Nonetheless, prompt identification of such infections particularly within transplant patients is essential as they can lead to severe downstream sequelae, including graft loss and even death. We describe here a challenging case of fungal pyelonephritis complicating and potentially leading to DGF and further dialysis dependence within a renal transplant patient. Notably, we highlight the importance and clinical utility of biopsy to confirm the diagnosis, as investigations may be largely normal otherwise. Furthermore, we emphasise that with early identification of these infections, effective antifungal treatment can be commenced in a timely fashion leading to better patient outcomes and good graft function.

Cerebral small vessel disease and intracranial bleeding risk: Prognostic and practical significance

Balancing the risks of recurrent ischemia and antithrombotic-associated bleeding, particularly intracranial hemorrhage (ICH), is a key challenge in the secondary prevention of ischemic stroke and transient ischemic attack. In hyperacute ischemic stroke, the use of acute reperfusion therapies is determined by the balance of anticipated benefit and the risk of ICH. Cerebral small vessel disease (CSVD) causes most spontaneous ICH. Here, we review the evidence linking neuroimaging markers of CSVD to antithrombotic and thrombolytic-associated ICH, with emphasis on cerebral microbleeds (CMB). We discuss their role in the prediction of ICH, and practical implications for clinical decision making. Although current observational data suggest CMB presence should not preclude antithrombotic therapy in patients with ischemic stroke or TIA, they are useful for improving ICH risk prediction with potential relevance for determining the optimal secondary prevention strategy, including the use of left atrial appendage occlusion. Following ICH, recommencing antiplatelets is probably safe in most patients, while the inconclusive results of recent randomized controlled trials of anticoagulant use makes recruitment to ongoing trials (including those testing left atrial appendage occlusion) in this area a high priority. Concern regarding CSVD and ICH risk after hyperacute stroke treatment appears to be unjustified in most patients, though some uncertainty remains regarding patients with very high CMB burden and other risk factors for ICH. We encourage careful phenotyping for underlying CSVD in future trials, with the potential to enhance precision medicine in stroke.

245 Cognitive function in patients with a long-standing diagnosis of SWEDD

Introduction

Patients with clinical features of Parkinson’s Disease (PD), but scans without evidence of dopaminergic deficit are termed SWEDDs. Only a portion of these patients retain their SWEDDs diagnosis later in life and are here regarded as ‘true SWEDDs’. Cognitive symptoms of ‘true SWEDDs’ remain unclear yet important to optimise their management. We used data from the Parkinson’s Progression Markers Initiative to investigate these further.

Methodology

Baseline cognitive data of 25 SWEDDs, who retained diagnoses after 2 years of follow up (confirmed by normal 123I-FP-CIT SPECT scans), were compared with that of 62 de novo PD and 195 healthy control (HC) subjects. Data was analysed using SPSS Statistics.

Results

No significant difference was found when comparing ‘true SWEDDs’ to de novo PD patients and HCs in tests of global cognition, visuospatial function, executive function and attention. However, Hopkins Verbal Learning Test-Revised (HVLT-R) showed a significant difference between the three groups (P=0.004), maintained when specifically analysing ‘true SWEDDs’ versus HCs (P=0.009).

Conclusion

Our data suggest a significant difference in memory function between ‘true SWEDDs’ and HCs, as demonstrated by the HVLT-R test. This suggests memory-stimulating therapies are important for managing ‘true SWEDDs’, however further work is required to validate these findings.

aaronjesuthasan@gmail.com

Sex differences in intraorgan fat levels and hepatic lipid metabolism: implications for cardiovascular health and remission of type 2 diabetes after dietary weight loss

AIMS/HYPOTHESIS

Type 2 diabetes confers a greater relative increase in CVD risk in women compared with men. We examined sex differences in intraorgan fat and hepatic VLDL1-triacylglycerol (VLDL1-TG) export before and after major dietary weight loss.

METHODS

A group with type 2 diabetes (n = 64, 30 male/34 female) and a group of healthy individuals (n = 25, 13 male/12 female) were studied. Intraorgan and visceral fat were quantified by magnetic resonance and VLDL1-TG export by intralipid infusion techniques.

RESULTS

Triacylglycerol content of the liver and pancreas was elevated in people with diabetes with no sex differences (liver 16.4% [9.3-25.0%] in women vs 11.9% [7.0-23.1%] in men, p = 0.57, and pancreas 8.3 ± 0.5% vs 8.5 ± 0.4%, p = 0.83, respectively). In the absence of diabetes, fat levels in both organs were lower in women than men (1.0% [0.9-1.7%] vs 4.5% [1.9-8.0%], p = 0.005, and 4.7 ± 0.4% vs 7.6 ± 0.5%, p< 0.0001, respectively). Women with diabetes had higher hepatic VLDL1-TG production rate and plasma VLDL1-TG than healthy women (559.3 ± 32.9 vs 403.2 ± 45.7 mg kg-1 day-1, p = 0.01, and 0.45 [0.26-0.77] vs 0.25 [0.13-0.33] mmol/l, p = 0.02), whereas there were no differences in men (548.8 ± 39.8 vs 506.7 ± 29.2 mg kg-1 day-1, p = 0.34, and 0.72 [0.53-1.15] vs 0.50 [0.32-0.68] mmol/l, p = 0.26). Weight loss decreased intraorgan fat and VLDL1-TG production rates regardless of sex, and these changes were accompanied by similar rates of diabetes remission (65.4% vs 71.0%) and CVD risk reduction (59.8% vs 41.5%) in women and men, respectively.

CONCLUSIONS/INTERPRETATION

In type 2 diabetes, women have liver and pancreas fat levels as high as those of men, associated with raised hepatic VLDL1-TG production rates. Dynamics of triacylglycerol turnover differ between sexes in type 2 diabetes and following weight loss. These changes may contribute to the disproportionately raised cardiovascular risk of women with diabetes.

Assessing initial MRI reports for suspected CJD patients

BACKGROUND

MRI is invaluable for the pre-mortem diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD), demonstrating characteristic diffusion abnormalities. Previous work showed these changes were often not reported (low sensitivity), leading to eventual diagnosis at a more advanced state. Here, we reviewed the situation a decade later, on the presumption of improved access and awareness over time.

METHODS

We reviewed initial MRI scans of 102 consecutive suspected sCJD patients recruited to the National Prion Monitoring Cohort study between 2015 and 2019, assessing for characteristic signal changes in the striatum, thalamus and cortical ribbon. We compared our findings to formal reports from referring centres. Requesting indications were studied to assess if they were suggestive of CJD. Patients were examined and their MRC Prion Disease Rating Scale scores recorded.

RESULTS

We identified characteristic MRI abnormalities in 101 cases (99% sensitivity), whilst referring centres reported changes in 70 cases (69% sensitivity), which was a significant improvement in reporting sensitivity from 2012. Reporting sensitivity was associated with signal change in the cerebral cortex, and with the number of regions involved, but not significantly affected by clinical information on request forms, or referring centres being regional neuroscience/non-neuroscience centres. Similar to a previous study, patients with missed abnormalities on initial reporting possessed lower MRC Scale scores when referred to the NPC than those correctly identified.

CONCLUSIONS

Whilst local MRI reporting of sCJD has improved with time, characteristic abnormalities remain significantly under detected on initial scans. Sensitivity is better when the cerebral cortex and multiple regions are involved. We re-emphasize the utility of MRI and encourage further efforts to improve awareness and sensitivity in the assessment of patients with rapidly progressive dementia.

Emerging potential mechanisms and predispositions to the neurological manifestations of COVID-19

A spectrum of neurological disease associated with COVID-19 is becoming increasingly apparent. However, the mechanisms behind these manifestations remain poorly understood, significantly hindering their management. The present review subsequently attempts to address the evolving molecular, cellular and systemic mechanisms of NeuroCOVID, which we have classified as the acute and long-term neurological effects of COVID-19. We place particular emphasis on cerebrovascular, demyelinating and encephalitic presentations, which have been reported. Several mechanisms are presented, especially the involvement of a "cytokine storm". We explore the genetic and demographic factors that may predispose individuals to NeuroCOVID. The increasingly evident long-term neurological effects are also presented, including the impact of the virus on cognition, autonomic function and mental wellbeing, which represent an impending burden on already stretched healthcare services. We subsequently reinforce the need for cautious surveillance, especially for those with predisposing factors, with effective clinical phenotyping, appropriate investigation and, if possible, prompt treatment. This will be imperative to prevent downstream neurological sequelae, including those related to the long COVID phenotypes that are being increasingly recognised.

Management of Secondary Poor Response to Botulinum Toxin in Cervical Dystonia: A Multicenter Audit

Background

Botulinum toxin A (BoNT‐A) is an effective treatment for cervical dystonia. Nevertheless, up to 30% to 40% patients discontinue treatment, often because of poor response. The British Neurotoxin Network (BNN) recently published guidelines on the management of poor response to BoNT‐A in cervical dystonia, but adherence to these guidelines has not yet been assessed.

Objectives

To assess adherence to and usefulness of BNN guidelines in clinical practice.

Methods

We undertook a retrospective medical notes audit of adherence to the BNN guidelines in 3 United Kingdom tertiary neurosciences centers.

Results

Of 76 patients identified with poor response, 42 (55%) had a suboptimal response and, following BNN recommendations, 25 of them (60%) responded to adjustments in BoNT dose, muscle selection or injection technique. Of the remaining 34 (45%) patients with no BoNT response, 20 (59%) were tested for immune resistance, 8 (40%) of whom showed resistance. Fourteen (18%) of all patients were switched to BoNT‐B, and 27 (36%) were referred for deep brain stimulation surgery. In those not immune to BoNT‐A, clinical improvement was seen in 5 (41%) after adjusting their dose and injection technique.

Conclusion

Our audit shows that optimizing BoNT dose or injection strategy largely led to improvements in those with suboptimal response and in those reporting no response without resistance. It would be helpful to standardize investigations of potential resistance in those with no therapeutic response.

Acute ischemic stroke management: concepts and controversies.A narrative review

INTRODUCTION

Amongst the 25.7 million survivors and 6.5 million deaths from stroke between 1990 and 2013, ischemic strokes accounted for approximately 70% and 50% of the cases, respectively. With patients still suffering from complications and stroke recurrence, more questions have been raised as to how we can better improve patient management.

AREAS COVERED

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and Newcastle-Ottawa Scale (NOS) were adopted to ensure a comprehensive inclusion of quality literature from various sources. PubMed and Embase were searched for evidence on thrombolysis, mechanical thrombectomy, artificial intelligence (AI), antiplatelet therapy, anticoagulation and hypertension management.

EXPERT OPINION

The directions of future research in these areas are dependent on the current level of validation. Endovascular therapy and applications of AI are relatively new compared to the other areas discussed in this review. As such, future studies need to focus on validating their efficacy. As for thrombolysis, antiplatelet and anticoagulation therapy, their efficacy has been well-established and future research efforts should be directed toward adjusting its use according to patient-specific factors, starting with factors with the most clinical relevance and prevalence.

Hepatic Lipoprotein Export and Remission of Human Type 2 Diabetes after Weight Loss

The role of hepatic lipoprotein metabolism in diet-induced remission of type 2 diabetes is currently unclear. Here, we determined the contributions of hepatic VLDL1-triglyceride production rate and VLDL1-palmitic acid content to changes in intra-pancreatic fat and return of first phase insulin response in a subgroup of the Diabetes Remission Clinical Trial. Liver fat, VLDL1-triglyceride production, and intra-pancreatic fat decreased after weight loss and remained normalized after 24 months of remission. First-phase insulin response remained increased only in those maintaining diabetes remission. Compared with those in remission at 24 months, individuals who relapsed after initial remission had a greater rise in the content of VLDL1-triglyceride and VLDL1-palmitic acid, re-accumulated intra-pancreatic fat, and lost first-phase response by 24 months. Thus, we observed temporal relationships between VLDL1-triglyceride production, hepatic palmitic acid flux, intra-pancreatic fat, and β-cell function. Weight-related disordered fat metabolism appears to drive development and reversal of type 2 diabetes.

Anaesthesia use in catheter ablation for atrial fibrillation: a systematic review and meta-analysis of observational studies

Objectives

This meta-analysis and systematic review seeks to compare both characteristic parameters and procedural outcomes of atrial fibrillation (AF) catheter ablation in patients under general anaesthesia (GA)/deep sedation and mild/moderate sedation.

Background

Catheter ablation has become a widely applied intervention for treating symptomatic AF and arrhythmias that are refractory to medical therapy. It can be conducted through from mild sedation to GA.

Methods

PubMed and Embase were searched up to July 2018 for randomised controlled trials, cohort and observational studies that assessed the outcomes of catheter ablation under GA/deep sedation or mild/moderate sedation. Nine studies were included in this meta-analysis after screening with the inclusion and exclusion criteria. Heterogeneity between studies and publication bias was evaluated by I² index and Egger's regression, respectively.

Results

Our meta-analysis found catheter AF ablation with GA/deep sedation to be associated with reduced risk of recurrence (RR: 0.79, 95% CI 0.56 to 1.13, p=0.20) and complications (RR: 0.95, 95% CI 0.64 to 1.42, p=0.82), though statistically insignificant. In terms of procedural parameters, there was no significant difference between the two groups for both procedural time (SMD: -0.13, 95% CI -0.90 to 0.63, p=0.74) and fluoroscopy time (SMD: -0.41, 95% CI -1.40 to 0.58, p=0.41). Univariate meta-regression did not reveal any covariates as a moderating factor for complication and recurrence risk.

Conclusion

Apart from an increased likelihood of procedural success, ablation by GA/deep sedation was found to be non-significantly different from the mild/moderate sedation approach in both procedural parameters and outcome measures.

P65 Implementing a pain scale to improve botulinum toxin practice for cervical dystonia

Objectives

To evaluate the effectiveness of introducing a pain scale to improve cervical dystonia (CD) patient satisfaction rates in the National Hospital for Neurology and Neurosurgery (NHNN) Botox clinic.

Design

Case control study.

Subjects

Subjects included CD patients attending the NHNN Botox clinic to receive injections.

Methods

Injectors were educated about the Toronto Western Spasmodic Torticollis Rating pain subscale (TWSTRS) and subsequently incorporated it into their standard assessment of CD patients prior to injections. Surveys were created and disseminated to patients immediately following their appointment to assess their opinions of the clinical team. Information was entered into Microsoft Excel and analysed using appropriate statistical methods. Results were compared with a previous NHNN Botox clinic audit.

Results

42 surveys were collected in total from CD patients over a 4 week period. 36 patients (85.7%) reported pain associated with the condition. In comparison to an audit conducted in 2016, involving a similar sample size (n=40, with 28 reporting pain), a higher proportion of CD patients felt their pain was well understood by the clinical team (89.3% vs 94.4%). Furthermore, a higher proportion felt the team were competent in managing their pain (67.9% vs 94.4%).

Conclusions

Our study supports the use of a TWSTRS pain subscale to improve CD patient satisfaction rates in the Botox clinic. Further studies are encouraged to validate these findings and determine other suitable pain scales for implementation.

The Current State of Mobile Phone Apps for Monitoring Heart Rate, Heart Rate Variability, and Atrial Fibrillation: Narrative Review

Background

Mobile phone apps capable of monitoring arrhythmias and heart rate (HR) are increasingly used for screening, diagnosis, and monitoring of HR and rhythm disorders such as atrial fibrillation (AF). These apps involve either the use of (1) photoplethysmographic recording or (2) a handheld external electrocardiographic recording device attached to the mobile phone or wristband.

Objective

This review seeks to explore the current state of mobile phone apps in cardiac rhythmology while highlighting shortcomings for further research.

Methods

We conducted a narrative review of the use of mobile phone devices by searching PubMed and EMBASE from their inception to October 2018. Potentially relevant papers were then compared against a checklist for relevance and reviewed independently for inclusion, with focus on 4 allocated topics of (1) mobile phone monitoring, (2) AF, (3) HR, and (4) HR variability (HRV).

Results

The findings of this narrative review suggest that there is a role for mobile phone apps in the diagnosis, monitoring, and screening for arrhythmias and HR. Photoplethysmography and handheld electrocardiograph recorders are the 2 main techniques adopted in monitoring HR, HRV, and AF.

Conclusions

A number of studies have demonstrated high accuracy of a number of different mobile devices for the detection of AF. However, further studies are warranted to validate their use for large scale AF screening.

Cervical Dystonia Following Injury to the Cerebellar Pontine Angle: An Instructive Case

A 38-year-old woman presented with cervical dystonia in the context of a recent surgery to remove a vestibular schwannoma. She initially presented to neurology with pain in the right arm, and MRI of the brain showed an incidental right-sided vestibular schwannoma (Video 1, Segment 1). An elective gamma-knife procedure was performed, which failed. Hydrocephalus requiring ventriculoperitoneal shunt insertion developed, and 3 years following the initial procedure the lesion was surgically excised. Surgery was further complicated by right middle cerebellar peduncle injury, extending to the cerebellopontine angle and marginally to the right pontine tegmentum, with subsequent mass effect on cerebellum displayed on follow-up MRI (Video 1, Segment 2). Six months later, the patient experienced forced head deviation to the right, with difficulty moving from this position. Examination revealed clear right-sided torticollis, with hypertrophy of the left sternocleidomastoid muscle. Cervical dystonia worsened with action and nearly resolved with the patient lying down. A clear geste antagoniste, where symptoms improved with the patient touching the side of her head, was present (Video 1, Segment 3). Findings consistent with injury to the cerebellar pathways were additionally exhibited. She demonstrated clear dysarthria, bilateral dysmetria, dysdiadochokinesia (worse on the right), and prominent gait ataxia (Video 1, Segment 4). Although a possible role of the schwannoma itself in the cervical dystonia pathogenesis cannot be entirely ruled out, the timing of signs, occurring soon after the postsurgical injury, suggest a prominent involvement of structures lying within the cerebellar pontine angle.

Cancer antigen-125 and outcomes in acute heart failure: a systematic review and meta-analysis

Background

Carbohydrate antigen-125 (CA125) is an ovarian cancer marker, but recent work has examined its role in risk stratification in heart failure. A recent meta-analysis examined its prognostic value in heart failure generally. However, there has been no systematic evaluation of its role specifically in acute heart failure (AHF).

Methods

PubMed and EMBASE databases were searched until 11 May 2018 for studies that evaluated the prognostic value of CA125 in AHF.

Results

A total of 129 and 179 entries were retrieved from PubMed and EMBASE. Sixteen studies (15 cohort studies, 1 randomised trial) including 8401 subjects with AHF (mean age 71 years old, 52% male, mean follow-up 13 months, range of patients 525.1±598.2) were included. High CA125 levels were associated with a 68% increase in all-cause mortality (8 studies, HRs: 1.68, 95% CI 1.36 to 2.07; p<0.0001; I²: 74%) and 77% increase in heart failure-related readmissions (5 studies, HRs: 1.77, 95% CI 1.22 to 2.59; p<0.01; I²: 73%). CA125 levels were higher in patients with fluid overload symptoms and signs compared with those without them, with a mean difference of 54.8 U/mL (5 studies, SE: 13.2 U/mL; p<0.0001; I²: 78%).

Conclusion

Our meta-analysis found that high CA125 levels are associated with AHF symptoms, heart failure-related hospital readmissions and all-cause mortality. Therefore, CA125 emerges as a useful risk stratification tool for identifying high-risk patients with more severe fluid overload, as well as for monitoring following an AHF episode.

274 Exome analysis to investigate autosomal dominant vasovagal syncope

Introduction

Vasovagal syncope (VVS) is the most common cause of syncope in children and adults. Previous studies suggest a genetic component accounts for approximately 20% of cases, although the genes responsible are often unidentified. I studied the DNA of two distantly related individuals with VVS enrolled into the 100,000 Genomes Project to identify causal mutations.

Method

DNA was extracted from the patients, and analysed using an Ingenuity Variant Analysis program to detect the presence of mutations. The severity of each detected mutation was subsequently examined using two programs: Sorting Intolerant from Tolerant (SIFT) and Polymorphing Phenotyping v2 (PolyPhen-2).

Results

Using Ingenuity Variant Analysis, a mutation in the ACE (Angiotensin Converting Enzyme), EPAS1 (Endothelial PAS Domain Protein 1) and PLCG2 (Phospholipase C Gamma 2) genes of the VVS patients were identified. Further analysis using SIFT and PolyPhen-2 indicated the ACE mutation was likely to produce a defective protein whilst the EPAS1 and PLCG2 mutations were unlikely to have any effect on protein function.

Conclusion

My results support the involvement of the ACE mutation in the cause of VVS within the two studied patients. This may point towards a novel target for therapy within the individuals, should the findings be successfully validated.