Interictal Neurological Examination Research Articles

Phenotypic Findings in Patients With KCNJ2-Related Anderson-Tawil Syndrome.

A 47-year-old woman presented with transient episodes of generalized weakness. Interictal neurologic examination was normal. Long exercise testing (Figure 1) demonstrated a delayed decrement in compound motor action potential amplitude, supporting the diagnosis of periodic paralysis.

Primary Cutibacterium Acnes Leptomeningeal Abscess Causing Focal Seizures

A previously well 71-year-old male presented with recurrent stereotyped episodes of right hemisensory disturbance, weakness, and expressive dysphasia lasting 10-20 minutes. Cognitive decline had been noted over the preceding 6-months. He was otherwise in good health with no history of infective symptoms or prior neurosurgical procedures. Interictal neurological examination was unremarkable.

Diagnostic utility of cerebrospinal fluid analysis in dogs with suspected idiopathic epilepsy.

Idiopathic epilepsy (IE) is the most common cause of repeated seizures in dogs. The International Veterinary Epilepsy Task Force consensus guidelines recommend performing magnetic resonance imaging (MRI) of the brain and cerebrospinal fluid (CSF) analysis as part of a tier II diagnosis of IE, and these procedures have documented risks. The aim of this retrospective study was to identify how often dogs with suspected IE have abnormalities on CSF analysis. Dogs aged between 6 months and 6 years that were presented with a history of two or more seizures with at least 24 h between seizure episodes, a normal neurologic examination, no evidence of toxic or metabolic causes, a normal MRI scan (including contrast administration) and CSF analysis were included. Eighty-two dogs were included. Of these, nine dogs (10.9%) had abnormalities on CSF analysis: five of nine dogs (55.5%) had albuminocytologic dissociation, three of nine dogs (33.3%) had mild increases in total nucleated cell count (TNCC), and one of nine dogs (11.1%) had mild increase in both total protein and TNCC. Cytology in dogs with elevated TNCC revealed a mononuclear pleocytosis. One of the nine dogs with abnormal CSF had a seizure within the 24 h before investigations, and six of nine dogs had a seizure within 1 month before investigation. CSF analysis can play an important role in the diagnostic investigation of the underlying causes of repeated seizures. However, in dogs with a normal inter-ictal neurological examination and MRI scan, it rarely reveals significant abnormalities, and the risk of performing a CSF tap may outweigh the potential diagnostic gain.

Diagnostic value of cerebrospinal fluid analysis in a population of dogs with suspected idiopathic epilepsy

Cerebrospinal fluid (CSF) analysis is commonly used in the diagnostic investigation of seizure disorders in order to exclude possible inflammatory underlying aetiology. The medical records were searched for dogs presenting...

First‐ever convulsive seizures in children presenting to the emergency department: risk factors for seizure recurrence and diagnosis of epilepsy

Aetiologies of first-ever convulsive seizures may be diverse, not all leading to recurrence or epilepsy diagnosis. We aimed to describe the epidemiology of first-ever convulsive seizures in children, investigating risk factors for recurrence and epilepsy diagnosis. This was a retrospective study of children presenting with a first-ever convulsive seizure to a tertiary-care paediatric emergency department (PED) in Italy, in a 12-month period (2011-2012). One hundred and eight children (57 males, 51 females) presented to the PED for a first-ever convulsive seizure; 90.7% were 6months to 6years old (median age 1y 10mo, mean 2y 7mo, range 0mo-14y 4mo). Seizure duration was less than 5minutes in 76.8%. Seizures were 'unprovoked' in 19.4% and 'provoked' in 80.6%. At 4-year follow-up, 37.9% of patients experienced recurrence and 13.6% received a diagnosis of epilepsy. Factors significantly associated with recurrence were the 'unprovoked' nature of the first seizure, multiple seizures in the first 24hours, positive family history of febrile seizures or epilepsy, and pre-existing neurological conditions/problems. Factors significantly associated with a diagnosis of epilepsy were the 'unprovoked' nature of the first seizure, age older than 6years, pre-existing neurological conditions/problems, and focal onset of first seizure. Children presenting to the PED with first-ever convulsive seizures represent a heterogeneous group. The identification of prognostic factors for recurrence and epilepsy diagnosis may help provide tailored counselling and follow-up. Seizures were 'unprovoked' in 19.4% and 'provoked' in 80.6% of children presenting to the emergency department. At 4-year follow-up, 37.9% relapsed, and 13.6% received a diagnosis of epilepsy. 'Unprovoked' first seizure, family history of febrile seizures, and pre-existing neurological conditions were associated with recurrence. 'Unprovoked' first seizure, age younger than 6years, and pre-existing neurological conditions were associated with epilepsy diagnosis.

Differentiating structural from idiopathic epilepsy in cats

IN 2015, the International Veterinary Epilepsy Task Force (IVETF) (www.ivetf.org) (Volk 2016) published several consensus reports, including one regarding the definition and classification of canine and feline epilepsy (Berendt and...

Status epilepticus in dogs and cats, part 1: etiopathogenesis, epidemiology, and diagnosis.

To review current knowledge of the etiopathogenesis, diagnosis, and consequences of status epilepticus (SE) in veterinary patients. Human and veterinary literature, including clinical and laboratory research and reviews. Status epilepticus is a common emergency in dogs and cats, and may be the first manifestation of a seizure disorder. It results from the failure of termination of an isolated seizure. Multiple factors are involved in SE, including initiation and maintenance of neuronal excitability, neuronal network synchronization, and brain microenvironmental contributions to ictogenesis. Underlying etiologies of epilepsy and SE in dogs and cats are generally classified as genetic (idiopathic), structural-metabolic, or unknown. Diagnosis of convulsive SE is usually made based on historical information and the nature of the seizures. Patient specific variables, such as the history, age of seizure onset, and physical and interictal neurological examination findings can help hone the rule out list, and are used to guide selection and prioritization of diagnostic tests. Electroencephalographic monitoring is routinely used in people to diagnose SE and guide patient care decisions, but is infrequently performed in veterinary medicine. Nonconvulsive status epilepticus has been recognized in veterinary patients; routine electroencephalography would aid in the diagnosis of this phenomenon in dogs and cats. Status epilepticus is a medical emergency that can result in life-threatening complications involving the brain and systemic organs. Status epilepticus often requires comprehensive diagnostic testing, treatment with multiple anticonvulsant agents, and intensive supportive care.

Magnetic resonance imaging findings in epileptic cats with a normal interictal neurological examination: 188 cases

Epilepsy is a common neurological condition in dogs and cats. Although an increased likelihood of significant brain lesions with age has been identified in neurologically normal dogs with epileptic seizures,...

Proline-rich Transmembrane Protein 2 Gene Mutation in a Sporadic Paroxysmal Kinesigenic Dyskinesia.

Dear Sir, A 12-year-old boy presented with paroxysmal events for the last 3 months. He had no adverse perinatal events and was developmentally normal. He experienced brief episodes of abnormal posturing of upper and lower limbs, usually on the right side. These episodes were triggered by sudden movements like sudden rise from sitting or lying position and sometimes by startle. There was absent premonitory sensation, preserved consciousness during the events, and no “postictal” drowsiness. The frequency was variable from 3 to 5 episodes/day to once in 2–3 days. There were no other body movements, myoclonus, dance-like movements, neuroregression, and hearing or vision impairment. There was no history of headaches or seizures in infancy. The family history was unremarkable for any seizures, movement disorder, or migraine. Examination was normal. Magnetic resonance imaging of his brain and his “interictal” electroencephalogram (EEG) were normal. He had poor response to oral valproate, started by a local practitioner. A possibility of paroxysmal kinesigenic dyskinesia (PKD) was considered in view of sudden movement/startle-induced paroxysmal dyskinesia. He had complete resolution of symptoms on oxcarbazepine. By direct sequencing of the entire coding region and exon-intron boundaries of the proline-rich transmembrane protein 2 (PRRT2) gene, the heterozygous mutation, c. 649dupC p. Arg217Profs*8 mutation, was identified in the patient. This mutation has been previously reported in patients with PKD from several parts of the world. PKD or DYT10, a rare movement disorder, may be sporadic or familial (autosomal dominant with incomplete penetrance). PRRT2 is the major gene responsible for PKD. The encoded protein, PRRT2, has presynaptic localization and appears to be involved in exocytosis and neurotransmitter release. The classical PKD phenotype is characterized by onset in childhood or adolescence; frequent brief attacks of dystonia, choreoathetosis, and/or ballismus with preserved consciousness; precipitation by sudden voluntary movements or startle; frequent aura; normal interictal neurological examination; and excellent response to anticonvulsants. The most effective drugs in PKD are voltage-gated sodium channel blockers (carbamazepine, oxcarbazepine, phenytoin, lacosamide). The common misdiagnosis is epilepsy, but preserved consciousness during the attacks, absence of postictal state, and absence of “ictal” EEG abnormalities favor PKD. The spectrum of PRRT2-associated diseases also includes benign familial infantile seizures, infantile convulsions with choreoathetosis, episodic ataxia, hemiplegic migraine, and benign paroxysmal torticollis of infancy.

The Evidence Behind the Diagnostic Investigation of Canine Idiopathic Epilepsy

Clinical bottom line
 There remains until recently an overall lack of clarity for the practical criteria for the diagnosis of canine idiopathic epilepsy. Signalment and an interictal neurological examination are vital for the diagnosis of idiopathic epilepsy. Despite the current insufficient evidence, the emerge of new diagnostic methods, such as cerebrospinal fluid and/or serum biomarkers, advanced functional neuroimaging techniques and electroencephalography, is likely to change the diagnostic approach in canine epilepsy in the near future.

International veterinary epilepsy task force consensus proposal: diagnostic approach to epilepsy in dogs.

This article outlines the consensus proposal on diagnosis of epilepsy in dogs by the International Veterinary Epilepsy Task Force. The aim of this consensus proposal is to improve consistency in the diagnosis of epilepsy in the clinical and research settings. The diagnostic approach to the patient presenting with a history of suspected epileptic seizures incorporates two fundamental steps: to establish if the events the animal is demonstrating truly represent epileptic seizures and if so, to identify their underlying cause. Differentiation of epileptic seizures from other non-epileptic episodic paroxysmal events can be challenging. Criteria that can be used to make this differentiation are presented in detail and discussed. Criteria for the diagnosis of idiopathic epilepsy (IE) are described in a three-tier system. Tier I confidence level for the diagnosis of IE is based on a history of two or more unprovoked epileptic seizures occurring at least 24 h apart, age at epileptic seizure onset of between six months and six years, unremarkable inter-ictal physical and neurological examination, and no significant abnormalities on minimum data base blood tests and urinalysis. Tier II confidence level for the diagnosis of IE is based on the factors listed in tier I and unremarkable fasting and post-prandial bile acids, magnetic resonance imaging (MRI) of the brain (based on an epilepsy-specific brain MRI protocol) and cerebrospinal fluid (CSF) analysis. Tier III confidence level for the diagnosis of IE is based on the factors listed in tier I and II and identification of electroencephalographic abnormalities characteristic for seizure disorders. The authors recommend performing MRI of the brain and routine CSF analysis, after exclusion of reactive seizures, in dogs with age at epileptic seizure onset <6 months or >6 years, inter-ictal neurological abnormalities consistent with intracranial neurolocalisation, status epilepticus or cluster seizure at epileptic seizure onset, or a previous presumptive diagnosis of IE and drug-resistance with a single antiepileptic drug titrated to the highest tolerable dose.This consensus article represents the basis for a more standardised diagnostic approach to the seizure patient. These recommendations will evolve over time with advances in neuroimaging, electroencephalography, and molecular genetics of canine epilepsy.Electronic supplementary materialThe online version of this article (doi:10.1186/s12917-015-0462-1) contains supplementary material, which is available to authorized users.

Discinesia paroxística cinesigénica familiar: descripción de una familia

Paroxysmal dyskinesias are movement disorders characterized by sudden episodes of involuntary movements. They are divided into kinesigenic, non-kinesigenic, and exercise-induced dyskinesias. Emphasis is made on the importance of the clinical history and fully describing the episodes in the differential diagnosis.The case is presented of a twelve year-old female with paroxysmal episodes of tongue torsion and dystonic postures of the upper limbs when start running or descending stairs and in the beginning of physical exercise, which ceased spontaneously seconds later. Some episodes were triggered by stress. In family history her father, paternal uncle, and sister also had paroxysmal movements. Interictal neurological examination was normal. Laboratory tests revealed a mutation in PRRT2 gene, which is related to neurological disorders such as paroxysmal kinesigenic dyskinesia, infantile convulsions and choreoathetosis migraine, episodic ataxia, paroxysmal torticollis, and intellectual disability. Treatment with carbamazepine was effective.

An exploratory study using a statistical approach as a platform for clinical reasoning in canine epilepsy

Links between deficits identified on neurological examination, age of seizure onset and the presence of structural forebrain disease have often been postulated in dogs presenting with a history of seizures. The purpose of this study was to assess the influence of such factors on the likelihood of structural or functional brain disease, via a thorough history taking process and interictal neurological examination. Four hundred and four dogs with seizures due to intracranial causes were included. Data including age, sex, neuter status, time until diagnosis, age of seizure onset in years, type of seizure, seizure symmetry, seizure severity, interictal neurological deficits, MRI changes and side effects associated with antiepileptic drugs were extracted from medical files.Two hundred and fifty-eight dogs were diagnosed with epilepsy of unknown origin (EUO), 11 with symmetrical structural lesions and 135 with asymmetrical structural lesions. Multinomial analysis demonstrated that dogs that were older at seizure onset were significantly more likely to have an asymmetrical structural lesion than EUO (OR 95% CI: 1.4–1.8). Dogs that had single seizures rather than cluster seizures were less likely to have asymmetrical structural lesions than dogs with EUO (OR 95% CI: 0.2–0.7). Dogs with abnormal neurological examinations were 16.5 times more likely to have asymmetrical structural lesions (OR 95% CI: 8.5–32.1) and 12.5 times more likely to have symmetrical structural lesions (OR 95% CI: 3.0–52.3) than EUO. These findings support the importance of considering interictal neurological deficits and seizure history in clinical reasoning.

De Novo Cluster Attacks after Intravenous Nitroglycerin Therapy (P03.215)

Objective: To describe a unique patient who experienced attacks of cluster headache (CH) after the administration of intravenous nitroglycerin (NTG) for Prinzmetal9s angina. Background NTG is widely utilized in the treatment of angina, and headache is a well-known side effect of this medication in both patients with and without a history of a primary headache disorder, including CH, which likely is from vasodilatory mechanisms. Patients with a prior history of primary headache disorders including CH may experience a delayed attack, characteristic of their typical headache, occurring up to 8 hours after stopping NTG infusion, likely secondary to direct neuronal and inflammatory mechanisms. To our knowledge, no patient has been described to have first onset CH attacks after NTG administration. Design/Methods: Case report from a tertiary medical center. Results: A 43 year old woman who previously only experienced infrequent episodic tension-type headache presented to our hospital with recurrent episodes of severe chest pain over 2 days, and was thought to have an ST-elevation myocardial infraction. Emergent cardiac catheterization revealed severe coronary vasospasm, consistent with Prinzmetal9s angina, and was treated successfully with an intravenous NTG infusion and subsequently verapamil. She subsequently experienced her first ever CH attacks, both within minutes after NTG initiation and 16 hours after its discontinuation. Both attacks were identical and characterized by 60 minutes of excruciating left orbital pain associated with moderate ptosis. Her interictal neurological examination, MRI and MRA of the brain were normal, and she experienced no subsequent attacks. Conclusions: This patient experienced de novo CH attacks from intravenous NTG. The delayed onset of CH attacks strongly suggests a direct neuronal or inflammatory mechanism rather than attacks occurring from intracranial vasodilation. Perhaps a brief cluster period itself was brought on by NTG, which was rapidly suppressed by both withdrawal of the agent and institution of verapamil. Disclosure: Dr. Agopian has nothing to disclose. Dr. Robbins has nothing to disclose.

Seizure‐Like Episodes in 3 Cats with Intermittent High‐Grade Atrioventricular Dysfunction

Reliance on history and description of episodes of collapse to differentiate seizures from syncope can be misleading. Syncope can have features of seizures or can be the cause of seizures. Clinical and neurologic examinations can also be misleading. High-grade atrioventricular (AV) block can be intermittent in cats and interictal neurologic examination can be normal in patients with epilepsy. In this report we describe highgrade AV dysfunction that mimicked epilepsy in 3 cats.

Juvenile Idiopathic Epilepsy in Egyptian Arabian Foals: 22 Cases (1985–2005)

Background:Epilepsy is relatively uncommon in horses compared with other species and limited information is available.Hypothesis:The objectives of the study were to describe the age of onset, clinical signs, clinicopathologic data, electroencephalographic findings, treatment, and outcome, including long‐term prognosis in Arabian foals with idiopathic epilepsy.Animals:Twenty‐two foals were included in the study.Materials and Methods: Medical records from 1985 to 2005 were reviewed.Results:The age of onset of affected foals ranged from 2 days to 6 months. Seizures were characterized by generalized tonic and clonic motor activity, staring, and loss of consciousness. The most common postictal signs were transient blindness and abnormal mental status. The interictal neurologic examination was otherwise normal. Clinicopathologic data and imaging diagnostics were normal except in 4 foals that developed complications. Electroencephalography revealed epileptiform activity in 9 of 13 foals. Foals were treated with benzodiazepines for the short‐term; whereas phenobarbital was used over the long‐term. Potassium bromide was added in 3 foals in which seizures were multiple, frequent, and difficult to control. The long‐term prognosis was favorable with cessation of seizures by 1 year of age. The most common complication was head trauma. The most common concurrent disease was pneumonia.Conclusions and Clinical Importance: Juvenile idiopathic epilepsy of Egyptian Arabian foals has an early clinical onset but appears to be self‐limiting. Information obtained from this study strongly suggests a heritable condition that merits further investigation.

Juvenile Idiopathic Epilepsy in Egyptian Arabian Foals: 22 Cases (1985–2005)

Epilepsy is relatively uncommon in horses compared with other species and limited information is available. The objectives of the study were to describe the age of onset, clinical signs, clinicopathologic data, electroeticephalographic findings, treatment, and outcome, including long-term prognosis in Arabian foals with idiopathic epilepsy. Twenty-two foals were included in the study. Medical records from 1985 to 2005 were reviewed. The age of onset of affected foals ranged from 2 days to 6 months. Seizures were characterized by generalized tonic and clonic motor activity, staring, and loss of consciousness. The most common postictal signs were transient blindness and abnormal mental status. The interictal neurologic examination was otherwise normal. Clinicopathologic data and imaging diagnostics were normal except in 4 foals that developed complications. Electroencephalography revealed epileptiform activity in 9 of 13 foals. Foals were treated with benzodiazepines for the short-term; whereas phenobarbital was used over the long-term. Potassium bromide was added in 3 foals in which seizures were multiple, frequent, and difficult to control. The long-term prognosis was favorable with cessation of seizures by 1 year of age. The most common complication was head trauma. The most common concurrent disease was pneumonia. Juvenile idiopathic epilepsy of Egyptian Arabian foals has an early clinical onset but appears to be self-limiting. Information obtained from this study strongly suggests a heritable condition that merits further investigation.

Transient global amnesia occurring as migraine aura

We describe a case of transient global amnesia (TGA) occurring as migraine aura. TGA prevalence is higher among migraineurs and has been ascribed to spreading depression in the hippocampus. Our patient, a 38-year-old physician, developed migraine without aura in early adolescence and from age 20 years, had experienced rare attacks of migraine with aura,. At ages 36 and 38 years, he suffered two attacks of sudden-onset anterograde amnesia, which lasted 5 hours and were immediately followed by unilateral right-sided pounding headaches. Ictal neurological examination was normal except for fixation amnesia. Interictal brain magnetic resonance imaging (MRI) and neurological examination were normal. Thus, in our patient affected with migraine with and without aura, TGA occurred as the aura phase of two migraine attacks. Our case report suggests that TGA shares common mechanisms with migraine.

Recurrent pure sensory transient ischemic attacks: In vivo demonstration of associated thalamic infarction

We present a case study and literature review to clarify the pathoanatomic substrate of recurrent pure sensory transient ischemic attacks (TIAs). A 60-year-old woman had had over 50 transient episodes of left hemibody hypoesthesia over the previous 15 years. Interictal neurologic examination was normal. Magnetic resonance imaging (MRI) showed a small infarct in the ventroposterolateral (VPL) nucleus of the right thalamus. Symptoms resolved with warfarin therapy. Ischemia-related pure sensory symptoms present as one of two clinical syndromes: (a) sudden onset of persistent unilateral face, arm, and/or leg hypoesthesia/paresthesias, preceded by no or few TIAs, or (b) frequent espisodes of transient unilateral hypoesthesia/paresthesias not progressing to permanent deficit. The first is widely recognized; recent computed tomography/MRI series have reported 105 cases associated with thalamic, brainstem, or thalamocortical projection sensory pathway infarction. Although equally common, the syndrome of recurrent transient hemihypoesthesia is under-recognized and has a less well-described pathologic substrate. One previous case with postmortem documentation of a VPL thalamic infarction has been reported. We believe this is the first reported case of recurrent transient hemihypoesthesia associated with VPL thalamic infarction imaged in vivo.

New-onset seizures associated with human immunodeficiency virus infection: causation and clinical features in 100 cases

We attempt to define the significance and most common causes of new-onset seizures in patients with human immunodeficiency virus (HIV) infection. In addition, we review the seizure type, neurologic examination, and other clinical features to better address diagnostic and management issues in these patients. We reviewed 100 cases of new-onset seizures in HIV-infected patients who underwent complete evaluations at the University of California, San Francisco, hospitals. Seizures were the presenting symptom of HIV-related illness in 18 patients, six of whom developed no other HIV-related illness until at least four months after the first seizure. Common causes in the 100 patients included mass lesions, HIV encephalopathy, and meningitis. No cause for the seizures was found in 23 patients despite a complete evaluation. An underlying cause was found in all patients with focal neurologic deficits but in only two of 24 who had normal results on an interictal neurologic examination. Focal ictal features were not predictive of cause. A cause was found in all 12 patients with status epilepticus or medically refractory seizures. A total of 12 of the 87 (14%) patients who received phenytoin developed a hypersensitivity reaction. Despite the brevity of follow-up in some patients, many patients, including those with no definable cause, had multiple seizures prior to the administration of anticonvulsants. The direct effects of HIV on the brain may be the single most common cause of seizures in this population. We favor treatment of a single seizure in patients with HIV infection.