How to avoid a misdiagnosis in patients presenting with transient loss of consciousness

Paroxysmal Nonepileptic Events in Children: A Video Gallery and a Guide for Differential Diagnosis

Purpose

of review Paroxysmal Non-Epileptic Events (PNEEs) are a heterogeneous group of time-limited events, characterized by changes in motor or behavioral activity beginning abruptly and ending in a short time. Due to their manifestation, these conditions can clinically simulate seizures.

Recent findings:

These episodes belong to different categories including syncopal events, psychiatric disorders, movement disorders, and many others. PNEEs are a common cause of diagnostic mistakes and families’ concerns and the risk of useless and sometimes even injurious treatment is considerable. The high frequency of these manifestations in clinical practice makes PNEEs a diagnostic challenge for clinicians.

Aortic stenosis: An important cause of collapse to be considered in a polytrauma patient

Undiagnosed and underlying medical co-morbidities are known to have a role in the causation of or contribution to injuries sustained in cases of polytrauma. Syncope provoked by valvular heart disease is one such example. Thorough clinical assessment is needed to ensure such diagnoses are detected and treated, whilst ensuring a patient’s ongoing rehabilitation needs are met. Here, the authors report a case of polytrauma, most likely secondary to severe aortic stenosis, causing syncope which was diagnosed at a later stage due to ongoing symptomatology. Delay in picking up such diagnoses can contribute to mortality in these patients or affect morbidity by having a detrimental impact on a patient’s functional recovery.

Can Assessment of the Tongue on Brain MRI Aid Differentiation of Seizure from Alternative Causes of Transient Loss of Consciousness?

BACKGROUND AND PURPOSE

Transient loss of consciousness is commonly evaluated in the emergency department. Although typically caused by epileptic seizure, syncope, or psychogenic nonepileptic seizure, the underlying etiology is frequently misdiagnosed. Lateral tongue bites are reportedly a specific clinical finding of seizure. We have observed tongue signal abnormality suggesting bite injury on brain MR imaging after seizures. We hypothesized an association between tongue signal abnormality and seizure diagnosis among patients in the emergency department imaged for transient loss of consciousness. Our purposes were to determine the prevalence of tongue signal abnormality among this population and the predictive performance for seizure diagnosis.

MATERIALS AND METHODS

For this retrospective study including 82 brain MR imaging examinations, 2 readers independently assessed tongue signal abnormality on T2-weighted and T2-weighted FLAIR images. Discrepancies were resolved by consensus, and interrater reliability (Cohen κ) was calculated. The final diagnosis was recorded. Proportions were compared using the Fisher exact test.

RESULTS

Tongue signal abnormality was present on 19/82 (23%) MR imaging examinations. Interrater reliability was "substantial" (κ = 0.77). Seizure was diagnosed among 18/19 (95%) patients with tongue signal abnormality and 29/63 (46%) patients without it (P < .001). In our cohort, tongue signal abnormality conveyed 97% specificity, 95% positive predictive value, and 63% accuracy for seizure diagnosis.

CONCLUSIONS

Tongue signal abnormality was observed in 23% of the study cohort and conveyed 97% specificity and 95% positive predictive value for seizure diagnosis. By assessing and reporting tongue signal abnormality, radiologists may facilitate a timely and accurate diagnosis of seizure among patients imaged for transient loss of consciousness.

Adverse Events Among Emergency Department Patients With Cardiovascular Conditions: A Multicenter Study

STUDY OBJECTIVE

We aim to determine incidence and type of adverse events (adverse outcomes related to emergency care) among emergency department (ED) patients discharged with recent-onset atrial fibrillation, acute heart failure, and syncope.

METHODS

This 5-year prospective cohort study included high-acuity adult patients discharged with the 3 sentinel diagnoses from 6 tertiary care Canadian EDs. We screened all ED visits for eligibility and performed telephone interviews 14 days postdischarge to identify flagged outcomes: death, hospital admission, return ED visit, health care provider visit, and new or worsening symptoms. We created case summaries describing index ED visit and flagged outcomes, and trained emergency physicians reviewed case summaries to identify adverse events. We reported adverse event incidence and rates with 95% confidence intervals and contributing factor themes.

RESULTS

Among 4,741 subjects (mean age 70.2 years; 51.2% men), we observed 170 adverse events (3.6 per 100 patients; 95% confidence interval 3.1 to 4.2). Patients discharged with acute heart failure were most likely to experience adverse events (5.3%), followed by those with atrial fibrillation (2.0%) and syncope (0.8%). We noted variation in absolute adverse event rates across sites from 0.7 to 6.0 per 100 patients. The most common adverse event types were management issues, diagnostic issues, and unsafe disposition decisions. Frequent contributing factor themes included failure to recognize underlying causes and inappropriate management of dual diagnoses.

CONCLUSION

Among adverse events after ED discharge for patients with these 3 sentinel cardiovascular diagnoses, we identified quality improvement opportunities such as strengthening dual diagnosis detection and evidence-based clinical practice guideline adherence.

Syncopal attacks in children: Is it cardiac or epilepsy related?

BACKGROUND

Transient loss of consciousness (TLOC) may be mistaken for other disorders like epilepsy. Our objectives were to identify symptoms that could help differentiate epilepsy from syncope among children with TLOC and to validate previously suggested criteria.

METHODS

We retrospectively reviewed the charts of patients aged 18 years or younger who presented with TLOC attacks from January 2008 to December 2018 at King Saud University Medical City, Riyadh, Saudi Arabia. Symptoms from which epilepsy and syncope could be predicted with high accuracy were included in the previously suggested criteria. The discriminative abilities of current and previous criteria were examined in receiver-operating characteristic analyses.

RESULTS

Data from 46 patients, 32 with confirmed epilepsy and 14 with syncope, were included in this analysis. The mean age was 12.1 years (S.D., 4.3 years), and 60.9% of the patients were girls. According to our proposed criteria, the sensitivity, specificity, and accuracy of symptoms in predicting epilepsy were 68.8%, 85.7%, and 73.9%, respectively, and the area under the curve was 0.814 (confidence interval 0.686 to 0.941, P = 0.001). According to previously suggested criteria, the sensitivity, specificity, and accuracy of symptoms in predicting epilepsy were 63.2%, 62.5%, and 63.0%, respectively, and the area under the curve was 0.730 (confidence interval 0.541 to 0.92, P = 0.063).

CONCLUSIONS

A number of self-reported/observed symptoms can be used to distinguish epilepsy from syncope with high discriminative ability. The current findings still need to be validated in larger, preferably multiple populations before they can be safely relied upon.

Dispatch of a helicopter emergency medicine service to patients with a sudden, unexplained loss of consciousness of medical origin

Background

Sudden loss of consciousness (LOC) in the prehospital setting in the absence of cardiac arrest and seizure activity may be a challenge from a dispatcher’s perspective: The aetiology is varied, with many causes being transient and mostly self-limiting, whereas other causes are potentially life threatening. In this study we aim to evaluate the dispatch of HEMS to patients with LOC of medical origin, by exploring to which patients with a LOC HEMS is dispatched, which interventions HEMS teams perform in these patients, and whether HEMS interventions can be predicted by patient characteristics.

Methods

We performed retrospective cohort study of all patients with a reported unexplained LOC (e.g. not attributable to a circulatory arrest or seizures) attended by the Air Ambulance Kent, Surrey & Sussex (AAKSS), over a 4-year period (July 2013–December 2017). Primary outcome was defined as the number of HEMS-specific interventions performed in patients with unexplained LOC. Secondary outcome was the relation of clinical- and dispatch criteria with HEMS interventions being performed.

Results

During the study period, 127 patients with unexplained LOC were attended by HEMS. HEMS was dispatched directly to 25.2% of the patients, but mostly (74.8%) on request of the ground ambulance crews. HEMS interventions were performed in 65% of the patients (Prehospital Emergency Anaesthesia 56%, hyperosmolar therapy 21%, antibiotic/antiviral therapy 8%, vasopressor therapy 6%) and HEMS conveyed most patients (77%) to hospital. Acute neurological pathology was a prevalent underlying cause of unexplained LOC: 38% had gross pathology on their CT-scan upon arrival in hospital. Both GCS (r = − 0.60, p < .001) and SBP (r = 0.31, p < .001) were related to HEMS interventions being performed on scene. A GCS < 13 predicted the need for HEMS interventions in our population with a sensitivity of 94.9% and a specificity 75% (AUC 0.85).

Conclusion

HEMS dispatchers and ambulance personnel are able to identify a cohort of patients with unexplained LOC of medical origin who suffer from potentially life threatening (mainly neurological) pathology, in whom HEMS specific intervention are frequently required. Presenting GCS can be used to inform the triage process of patients with LOC at an early stage.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-020-00388-x.

Orthostatic hypotension: clinical review and case study

Transient loss of consciousness (TLOC) accounts for 3% of all attendance in emergency departments within the UK. More than 90% of TLOC presentations are due to epileptic seizures, psychogenic seizures or syncope. However, in England and Wales in 2002, it was estimated that 92 000 patients were incorrectly diagnosed with epilepsy, at an additional annual cost to the NHS of up to £189 million. This article will reflect on the case study of a 54-year-old female patient who presented with a possible TLOC, and had a background of long-term depression. Differential diagnoses will be discussed, but the article will focus on orthostatic hypotension. Being diagnosed with this condition is independently associated with an increased risk of all-cause mortality. Causes of orthostatic hypotension and the pathophysiology behind the condition will be discussed, highlighting the importance of obtaining an accurate clinical history. This is extremely pertinent if a patient collapses in an NHS setting and this is witnessed by nurses because they can contribute to the history of the type of collapse, to aid diagnosis and correct treatment. In addition, nurses have a valuable role to play in highlighting polypharmacy to doctors, and non-medical prescribers, as a contributing factor to orthostatic hypotension is polypharmacy. It is therefore important to accurately distinguish TLOC aetiology, not only to provide appropriate management, but to also identify patients at risk of morbidity/mortality related to underlying disease.

Seizures as the first clinical manifestation of acute pulmonary embolism: an underestimate issue in neurocritical care

BACKGROUND

The aim of the present review is to analyze the clinical characteristics of patients with acute pulmonary embolism (PE) which seizures were the first clinical manifestation of the disease.

METHODS

After screening 258 articles in PubMed, Scopus, Cochrane Library, and Google Scholar databases, we identified 16 case reports meeting the inclusion criteria.

RESULTS

The mean age of the population was 48.4 ± 19.8 years (9 males and 7 females). About three of four patients (68.7%) were hemodynamically stable at admission, having a systolic blood pressure > 90 mmHg. Intriguingly, the doubt of acute PE was based on clinical suspicion or on instrumental findings in 62.5% and 18.7% of patients, respectively. In 3 subjects (18.7%), the acute cardiovascular disease was not suspected. Half of patients had an unremarkable previous medical history while neurological comorbidities were present in 4 patients (25.0%). During seizures, a transient loss of consciousness (TLOC) was reported in 6 cases. Seizures were retrospectively classified according to the 2017 ILAE classification, whenever possible. A focal and generalized onset was reported in 37.5% and 50% of cases, respectively, in 12.5% of patient's data that were insufficient to classify the events. The mean number of seizure episodes in the population enrolled was 2.0 ± 1.1. Mortality rate was 54.5% but one investigation did not report the patient's outcome.

CONCLUSIONS

The relationship between seizures and acute PE is probably underrecognized. Identifying patients that have a high probability of acute PE is fundamental to avoid any treatment delay and ameliorate their outcomes.

Machine learning as a diagnostic decision aid for patients with transient loss of consciousness

Background

Transient loss of consciousness (TLOC) is a common reason for presentation to primary/emergency care; over 90% are because of epilepsy, syncope, or psychogenic non-epileptic seizures (PNES). Misdiagnoses are common, and there are currently no validated decision rules to aid diagnosis and management. We seek to explore the utility of machine-learning techniques to develop a short diagnostic instrument by extracting features with optimal discriminatory values from responses to detailed questionnaires about TLOC manifestations and comorbidities (86 questions to patients, 31 to TLOC witnesses).

Methods

Multi-center retrospective self- and witness-report questionnaire study in secondary care settings. Feature selection was performed by an iterative algorithm based on random forest analysis. Data were randomly divided in a 2:1 ratio into training and validation sets (163:86 for all data; 208:92 for analysis excluding witness reports).

Results

Three hundred patients with proven diagnoses (100 each: epilepsy, syncope and PNES) were recruited from epilepsy and syncope services. Two hundred forty-nine completed patient and witness questionnaires: 86 epilepsy (64 female), 84 PNES (61 female), and 79 syncope (59 female). Responses to 36 questions optimally predicted diagnoses. A classifier trained on these features classified 74/86 (86.0% [95% confidence interval 76.9%-92.6%]) of patients correctly in validation (100 [86.7%-100%] syncope, 85.7 [67.3%-96.0%] epilepsy, 75.0 [56.6%-88.5%] PNES). Excluding witness reports, 34 features provided optimal prediction (classifier accuracy of 72/92 [78.3 (68.4%-86.2%)] in validation, 83.8 [68.0%-93.8%] syncope, 81.5 [61.9%-93.7%] epilepsy, 67.9 [47.7%-84.1%] PNES).

Conclusions

A tool based on patient symptoms/comorbidities and witness reports separates well between syncope and other common causes of TLOC. It can help to differentiate epilepsy and PNES. Validated decision rules may improve diagnostic processes and reduce misdiagnosis rates.

Classification of evidence

This study provides Class III evidence that for patients with TLOC, patient and witness questionnaires discriminate between syncope, epilepsy and PNES.

Diagnostic criteria to aid the differential diagnosis of patients presenting with transient loss of consciousness: A systematic review

BACKGROUND

Transient loss of consciousness (TLOC) is a common presentation in primary care. Over 90% of these are due to epileptic seizures (ES), syncope, or psychogenic non-epileptic seizures (PNES). Misdiagnosis rates are as high as 30%.

METHODS

Systematic review of inter-ictal clinical criteria to aid differential diagnosis of TLOC. We searched Medline, EMBASE, CINAHL and PsycInfo databases, as well as relevant grey literature depositories and citations of relevant reviews and guidelines for studies giving sensitivity and specificity of inter-ictal clinical characteristics used to differentiate between causes of TLOC. Two independent reviewers selected studies for inclusion and performed critical appraisal of included articles. We performed a narrative synthesis of included studies.

RESULTS

Of 1023 results, 16 papers were included. Two compared syncope, ES, and PNES; all others compared ES and PNES. All were at significant risk of bias in at least one domain. 6 studied patient symptoms, 6 medical and social history, 3 witness reports and 1 examination findings. No individual criterion differentiated between diagnoses with high sensitivity and specificity.

CONCLUSIONS

There is a lack of validated diagnostic criteria to help clinicians assessing patients in primary or emergency care settings to discriminate between common causes of TLOC. Performance may be improved by combining sets of criteria in a clinical decision rule, but no such rule has been validated prospectively against gold-standard diagnostic criteria.

Does baseline depression increase the risk of unexplained and accidental falls in a cohort of community-dwelling older people? Data from The Irish Longitudinal Study on Ageing (TILDA)

BACKGROUND

Depression independently increases the risk of falls in older people, but the mechanism for this relationship, as well as the specific falls type involved, remains unclear. Accidental falls (AFs) are due to slips or trips, while the cause of unexplained falls (UFs) is not immediately apparent and can include unrecognised syncope.

METHOD

This longitudinal study examines the relationship between baseline depression and subsequent falls, both accidental and unexplained, at 2-year follow-up in a cohort of community dwelling adults aged ≥50 years. Baseline depression was defined as a score ≥16 on The Centre for Epidemiological Studies Depression Scale. At follow-up, participants were assessed regarding falls since last interview.

RESULTS

One-third (228/647) of the depressed group had fallen at follow-up, compared with 22% (1388/6243) of the nondepressed group (P < .001). Multiple logistic regression models demonstrated that depression was associated with an odds ratio of 1.58 (1.31-1.89) P < .001; 1.24 (1.00-1.52), P = .046; and 1.89 (1.45-2.46), P < .001 for total falls, AFs and UFs, respectively, after controlling for relevant covariates. Participants with depression who fell were more likely to have prior falls, functional impairment and slower gait when compared with depressed participants who did not fall.

DISCUSSION

The risk of falls associated with depression in older adults is more marked for UFs, with the association for AFs approaching borderline significance only. This finding is important because UFs require focused clinical assessment with attention to potential causes such as cardiac arrhythmia or orthostatic hypotension.

The +Gz recovery of consciousness curve

Background

The limiting physiological envelope to extreme gravitational stress is defined by neurologic symptoms and signs that result from exceeding neurologic tolerance. The edge of the limiting envelope is defined by the complete incapacitation associated with acceleration (+Gz) induced loss of consciousness. Should + Gz-induced loss of consciousness occur in-flight, brisk recovery of conscious function is essential for aircraft recovery. If recovery does not occur, accident investigation aimed at preventing such accidents is enhanced by understanding the temporal aspects of the resulting incapacitation. The mechanistic basis of neurological reintegration leading to consciousness recovery is of broad medical and scientific interest.

Methods

Recovery of consciousness episodes from a prospectively developed +Gz-induced loss of consciousness repository of healthy individuals was analyzed to define variables influencing recovery of consciousness. The time from loss to recovery of consciousness as measured by observable signs, is defined as the absolute incapacitation period. The absolute incapacitation period from 760 episodes of loss and recovery of consciousness in healthy humans was analyzed to define +Gz-profile variables that determine the duration of functional neurologic compromise.

Results

Mean time from loss to return of consciousness for 760 episodes of consciousness recovery was 10.4 ± 5.1 s; minimum 1 s; maximum 38 s. Offset rate for the +Gz-exposure deceleration profiles varied from a minimum of 0.17 Gs⁻¹ to a maximum of 7.93 Gs⁻¹.The curve produced by plotting +G_z-offset rate (Gs⁻¹; y) versus absolute incapacitation period (s; x) described a hyperbolic relationship. The hyperbolic relationship indicates there is a minimum time (mean 8.29 ± 3.84 s) required for recovery of consciousness when complete loss of consciousness occurs.

Conclusions

Mean recovery time from +Gz-induced unconsciousness is dependent on the deceleration profile's offset rate from the point of loss of consciousness. This relationship is described by a curve plotting offset rate and time for recovery of consciousness. This curve predicts when conscious function should return following exposure to +Gz stress sufficient to cause unconsciousness. The maximum +Gz level of the recovery exposure profile was found to be inadequate for predicting variations in the time for recovery of consciousness.

Clinical evaluation and risk stratification in patients with syncope

Syncope accounts for approximately 1 % of visits to emergency departments. The first diagnostic step is to rule out nonsyncopal conditions as a cause of the transient loss of consciousness. Next, the basic clinical evaluation should identify patients at high risk for potentially life-threatening events. These patients should be admitted and monitored until a diagnosis is made and definitive treatment can be offered. Guided by the basic evaluation findings, specific tests should be performed to prove or rule out the suspected diagnosis. In low-risk patients, this should preferably be done in an outpatient setting. To date, there is no consensus on a structured algorithm for the evaluation of patients with syncope. Therefore, it seems beneficial to formulate an algorithm based on the current guidelines for the management of syncope for use in the clinical setting.

Avoiding misdiagnosis in patients with neurological emergencies

Approximately 5% of patients presenting to emergency departments have neurological symptoms. The most common symptoms or diagnoses include headache, dizziness, back pain, weakness, and seizure disorder. Little is known about the actual misdiagnosis of these patients, which can have disastrous consequences for both the patients and the physicians. This paper reviews the existing literature about the misdiagnosis of neurological emergencies and analyzes the reason behind the misdiagnosis by specific presenting complaint. Our goal is to help emergency physicians and other providers reduce diagnostic error, understand how these errors are made, and improve patient care.

Epilepsy in later life

Epilepsy is most likely to develop in later life. The burden of this disorder on health-care resources will rise further as the world's population continues to age. Making a secure diagnosis can be challenging because the clinical manifestations of seizures and the differential diagnoses and causes of epilepsy can be different in older individuals compared with younger individuals. Obtaining a reliable account of the events for accurate assessment is particularly important in guiding the appropriate choice and interpretation of investigations to arrive at the correct diagnosis. In older age, unique pharmacokinetic and pharmacodynamic changes occur. The use and selection of antiepileptic drugs is often further complicated by the presence of comorbidities, polypharmacy, and concomitant functional impairment, but there is a paucity of high-level clinical evidence on the effects of these factors as well as on the choice of treatment in the elderly. A comprehensive model of care should combine expertise in the diagnosis and treatment of epilepsy with effective assessment and management of the psychosocial effects to improve the prognosis in this vulnerable and poorly studied group of patients.

Blackout? Cause: misdiagnosis of cardiac arrest

Patients with syncope or epilepsy commonly present to primary or secondary care physicians. This lesson presents two patients, both known to have cardiac disease, with implanted cardiac devices, who presented with loss of consciousness, who were initially investigated for epilepsy, but were subsequently shown to have had a cardiac arrhythmia, diagnosed following device interrogation.

Mendelian-inherited heart disease: a gateway to understanding mechanisms in heart disease Update on work done at the University of Stellenbosch

The presence of founder effects in South Africa for many single-gene diseases, which include heart diseases such as progressive familial heart block types I and II, hypertrophic cardiomyopathy and the long QT syndromes, afforded us the opportunity to identify causal genes and associated mutations through genetic mapping and positional cloning. From finding the genes, the emphasis has shifted to elucidating how primary defects cause disease and recognising factors that could explain the often pronounced phenotypic variability seen in persons carrying the same inherited defect. In some of these diseases, sudden unexpected death has been a frequent occurrence in young, apparently healthy individuals who had not been aware that they had inherited an underlying risk. Herein, we review progress in identifying genes, mutations and risk factors associated with the diseases mentioned.