Continuum Questions Flashcards
A 24-year-old man presents with medically intractable seizures since the age of 16. He has a combination of complex partial seizures, characterized by staring and “smelling burning rubber,” and generalized tonic-clonic seizures. He has failed treatment with four anticonvulsants: carbamazepine, phenytoin, lamotrigine, and levetiracetam. An MRI of his brain demonstrates atrophy of the right hippocampal formation. Video-EEG records three of his typical seizures, all of which originate from the anterior right temporal lobe. What is the likelihood that this patient would achieve excellent seizure control (ie, be seizure free, have auras only, or have marked reduction in seizures) with epilepsy surgery?
75%
A 65-year-old woman with a history of partial seizures that had been well controlled on phenytoin is evaluated for recurrent seizures. She developed postherpetic neuralgia in the right V2 distribution following a herpes zoster infection 3 months ago. Her MRI shows an old right frontal lobe infarct. Attempts to increase the dose of phenytoin result in drowsiness. Which of the following would be the most appropriate adjunct therapy in this patient?
Pregabalin
In patients with chronic neuropathic pain, pregabalin, gabapentin, oxcarbazepine, and lacosamide are possible options for adjunct treatment of seizures. Topiramate, lamotrigine, and levetiracetam have not yet been proven effective in this setting. Carbamazepine could be helpful but has the risk of drug interactions at the level of hepatic metabolism. F
A 30-year-old woman presents with new-onset partial epilepsy and is discovered to have a low-grade glioma. Her seizures persist despite resection of the tumor. In considering anticonvulsant therapy for this patient, which of the following medications is least likely to interact with her oral contraceptive medication?
LVT
Any hepatic enzyme-inducing antiepileptic drug (AED) can accelerate the metabolism of oral contraceptive pills (OCPs)
and render them less effective. Therefore, phenytoin, carbamazepine, and oxcarbazepine should be avoided. Lamotrigine is not metabolized by the hepatic enzymes, but OCPs may significantly reduce the level of lamotrigine. The dose of lamotrigine may need to be adjusted if OCPs are started or stopped during the course of AED treatment. Levetiracetam should be safe to use with OCPs and should not significantly affect drug effectiveness.
A 22 year-old-woman with idiopathic generalized epilepsy with generalized tonic-clonic seizures continues to have breakthrough seizures despite use of lamotrigine. Valproate is added to the regimen. Which of the following effects may result from interaction between these drugs?
Lamotrigine toxicity due to inhibition of its glucuronidation.
Valproate inhibits uridine glucosyl transferase, the enzyme that metabolizes lamotrigine. Initiation of valproate therapy may require immediate reduction of the dose of lamotrigine by 50%.
A 6-month-old previously healthy boy is evaluated for recurrent bouts of status epilepticus. The first episode occurred 3 months ago during an upper respiratory tract infection and consisted of twitching of the right side of his face and arm that progressed to a generalized tonic-clonic seizure; the whole event lasted approximately 40 minutes. The second, a similar episode lasting approximately 60 minutes, occurred 2 months ago within 24 hours of his routine immunization. A third episode occurred while he was being given a hot bath. It started with left arm twitching and progressed to a generalized tonic-clonic seizure, with a total duration of approximately 70 minutes. Since then, the patient has continued to have episodes of status epilepticus every 2 to 3 weeks. The EEG shows postictal slowing. The MRI of the head and laboratory studies are normal. The episodes decrease in frequency after stiripentol is added to a previously ineffective regime of valproate and clonazepam. This disorder has been linked to a mutation of which of the following genes?
SCN1A, encoding the sodium channel alpha1 subunit.
The history of recurrent, focal-onset, prolonged seizures starting in the first year of life and triggered by fever or other causes of increased body temperature suggests the diagnosis of
Dravet syndrome. Approximately 80% of cases have mutations of the SCN1A gene.
A 30-year-old woman presents to the emergency department in convulsive status epilepticus. She has been previously healthy, takes no medications, and uses no recreational drugs. Her spouse reports that she had stayed home from work the previous day because of a flulike illness with headache and mild fever. On examination, her vital signs are temperature 38°C, blood pressure 140/90 mm Hg, and heart rate 100 beats/min. She is given supplemental oxygen, and IV access is secured. The convulsions stop after 4-mg IV lorazepam is administered. She remains unconscious after the convulsions stop, with a nonfocal examination. The brainstem reflexes are intact. No meningismus is present. Serum glucose, electrolytes, aspartate aminotransferase, creatinine, and calcium levels are normal. A noncontrast
CT of the head is negative, and an urgent EEG shows left temporal periodic lateralized epileptiform discharges. Which of the following is the most appropriate next step in management?
Lumbar puncture
he development of status epilepticus in a patient with fever raises immediate concern for encephalitis. In the setting of temporal periodic lateralized epileptiform discharges, the most likely organism is herpes simplex. A patient with this presentation would likely be started on empiric therapy with acyclovir even before proceeding with additional testing. If additional anticonvulsant treatment is required, fosphenytoin would be a better choice than phenobarbital. Neither neuron-specific enolase nor MR angiography would be useful in this setting. IV ceftriaxone is active against bacterial causes of meningitis (eg, pneumococcus and Neisseria meningitidis) and may be started in conjunction with acyclovir in the less likely event of bacterial meningoencephalitis.
A 6-year-old boy is evaluated for episodes of sudden-onset behavioral arrest, unresponsiveness, and a blank stare. Which of the following additional
features would most likely argue against the diagnosis of absence seizure and support that of complex partial seizure in this child?
Postictal confusion.
Absence seizures are characterized by sudden behavioral arrest, unresponsiveness, and a blank stare, typically lasting for a few seconds to half a minute. This is referred to as simple absence. Absence seizures may be associated with clonic, tonic, or atonic components, automatisms, and autonomic features, in isolation or in combination (complex absence). The ictal EEG pattern is classically a 3-Hz generalized monomorphic spike and wave with abrupt onset and termination. Unlike the case of complex partial seizures, little or no postictal confusion follows absence seizures.
A 12-year-old boy with Lennox-Gastaut syndrome has had medically intractable generalized seizures since the age of 5. Seizure types include atypical absence, tonic, atonic, and tonic-clonic. He currently takes felbamate and rufinamide and has failed multiple other anticonvulsants in the past, including valproic acid, clonazepam, lamotrigine, and topiramate. Because he has fallen frequently as a result of his seizures, he must wear a protective helmet and use a wheelchair for ambulation. Which of the following is most likely to be helpful in reducing the severity of this patient’s seizures?
Corpus callosotomy.
Surgery for symptomatic generalized epilepsy is confined to corpus callosotomy. This procedure will reduce the frequency of epileptic drop attacks and other generalized seizure types. Although a complete callosotomy is the most effective procedure, it carries more operative risk than an anterior two-thirds corpus callosotomy. Potential complications include urinary incontinence, abulia, speech disorder, and difficulty walking. Additional anticonvulsants are unlikely to be helpful given this patient’s history. Focal cortical resection, as with amygdalohippocampectomy, would not be useful in a patient with primary generalized epilepsy. The role of thalamic stimulation remains a subject
of ongoing investigation but has not been proven to be helpful in Lennox-Gastaut syndrome. Vagal nerve stimulation may be useful in reducing seizure frequency in patients with Lennox-Gastaut syndrome but would not be expected to be as useful as corpus callosotomy.
A 32-year-old man with temporal lobe seizures and a history of depression and irritability is evaluated for poorly controlled seizures despite maximal tolerated doses of oxcarbazepine. Which of the following would be considered the preferred adjunctive drug for treatment of seizures in this patient?
Lamotrigine
Lamotrigine has demonstrated beneficial efficacy for treatment of depression in epilepsy. Levetiracetam should probably be avoided in patients with a history of irritability. Phenytoin would not be a good choice because of the risk of cumulative side effects. Zonisamide does not have known antidepressant effects. Felbamate has risk of aplastic anemia and hepatitis, so it should only be used when other appropriate medications fail.
A 33-year-old previously healthy man is evaluated for recent onset of spells characterized by abrupt onset of pallor, sweating, and palpitations lasting 60 to 90 seconds and recurring 5 to 6 times a day. During the episodes, he remains aware of his environment. He feels lightheaded when the episodes occur in a standing position. The episodes tend to occur early during the morning hours and sometimes awaken him from sleep. Neurologic and general medical examination is normal between the spells. Routine EKG, EEG, MRI of the head, and general laboratory studies are normal. Which of the following tests is most likely to provide a diagnosis of these events?
Video-EEG monitoring.
The stereotyped nature of the spells, their short duration (less than 2 minutes), and the fact that many of them arise from sleep strongly suggest seizures, most likely from the mesial temporal lobe. A normal interictal EEG, particularly if performed without sleep deprivation, does not exclude seizures as a cause of the events. In these cases, long-term video-EEG monitoring may be helpful. Some disorders associated with temporal lobe seizures, such as limbic encephalitis due to potassium channel antibodies, may show no abnormalities on routine MRI. The characteristics of the spells are not typical of orthostatic intolerance, cardiac arrhythmia, pheochromocytoma, or hypoglycemia.
A 35-year-old woman presents to the emergency department for evaluation of a 1-minute generalized tonic-clonic seizure occurring during sleep. Her past medical history is remarkable for hypertension, migraine, and a recent urinary tract infection. She has no prior history of seizure or head injury. Her medications include atenolol, lisinopril, sulfamethoxazole, and tramadol, each of which she has been taking daily and at maximal doses. Vital signs are normal. Her general and neurologic examinations are normal. Blood work, including glucose, aspartate aminotransferase, creatinine, electrolytes, and toxicology screen, is normal. An MRI of the brain shows no structural abnormality, and EEG is normal. Which of the following is the most appropriate next step in the management of this patient?
Discontinue tramadol.
his patient has had an acute, apparently unprovoked, generalized seizure. While the seizure may be idiopathic, it is important to consider symptomatic causes. In this patient, neither an obvious structural lesion nor an obvious metabolic abnormality is present. Tramadol has been associated with seizures, particularly in patients who have recently started taking the medication and/or are taking large doses. Tramadol should be discontinued. No clear indication for anticonvulsant medications exists if an acute reversible cause can be identified.
A 25-year-old woman presents with several episodes of speech and motor arrest associated with olfactory hallucinations. Her neurologic examination is normal. MRI shows mild left hippocampal atrophy. EEG demonstrates left temporal spike-wave discharges. She has a long history of obesity and bipolar affective disorder with mania and major depression, which has been moderately well controlled on lithium. Which of the following anticonvulsants would be the most appropriate medication for this patient?
Lamotrigine.
This patient has the coexistence of localization epilepsy and psychiatric disease, suggesting that she would benefit most from an anticonvulsant with mood-stabilizing effects and one that would not be likely to worsen her major depression. Valproic acid might be equally useful in this setting, but her obesity problem is more likely to be aggravated by valproic acid than by lamotrigine. Valproic acid, carbamazepine, and lamotrigine all have proven efficacy for the treatment and prevention of manic symptoms. Phenytoin, levetiracetam, and phenobarbital could all worsen her mood disturbance.
A 2-week-old girl is evaluated in the emergency department for frequent seizures characterized by brief multifocal jerks, sometimes associated with apnea, occurring 20 to 30 times daily. In between the episodes, she is alert and interactive. Screen for sepsis and metabolic disorder, MRI, and interictal EEG are normal. Her father and paternal aunt had similar episodes that resolved after several months and had no further problems. This disorder has been linked to mutations of which of the following genes?
KCNQ2, encoding a voltage-gated potassium channel.
he clinical picture is that of benign familial neonatal seizures, which have been linked to mutations of the KCNQ2 or KCNQ3 gene, encoding for a voltage-gated potassium channel that has a major role in regulating neuronal excitability.
70-year-old woman with a history of osteoporosis presents with newly diagnosed partial epilepsy believed to have resulted from an old right middle cerebral artery infarct. She was started on phenytoin in the emergency department 1 month ago. She is otherwise healthy and takes no medications other than aspirin, simvastatin, and a bisphosphonate. Which of the following anticonvulsants is most appropriate for long-term seizure control in this patient?
Lamotrigine.
ntiepileptic drugs that are inducers of the hepatic cytochrome P450 enzyme system (including phenytoin, phenobarbital, primidone, carbamazepine) increase the metabolism of vitamin D. Valproic acid is an inhibitor of the cytochrome P450 system but is also associated with altered bone metabolism and decreased bone mass. Lamotrigine has not been associated with bone loss and may be a better choice in this patient.
A 22-year-old woman with migraine and idiopathic generalized epilepsy well controlled on topiramate 150 mg 2 times a day is prescribed an oral contraceptive agent. Which of the following potential consequences of an interaction between these two drugs should be discussed with the patient?
Contraceptive failure caused by cytochrome (CYP) 3A4 induction by topiramate.
Topiramate at doses higher than 200 mg may induce CYP 3A4 isoenzymes and result in increased metabolism of steroid hormones with consequently reduced contraceptive efficacy.
A 33-year-old right-handed man is evaluated for spells characterized by a warm ascending sensation in the epigastrium associated with a sensation
of fear followed by loss of contact with the environment and oromandibular automatisms. During a recorded seizure, his right hand continually rubs his leg and his left arm remains immobile and stiff. The spells last 1 to 2 minutes. He is able to follow commands toward the end of the seizure. Which of the following is the most likely location of the ictal discharge?
Right mesial temporal.
The presence of epigastric aura, ipsilateral hand automatisms, contralateral dystonic posturing, and ictal preservation of speech and responsiveness and absence of postictal dysphasia are typical of nondominant mesial temporal lobe seizures.
A 45-year-old man with a long history of localization-related epilepsy develops major depression with suicidal ideation. He has had moderately good seizure control with carbamazepine, with his last seizure occurring 6 months ago. He has a flat affect with depressed mood. The remainder of his neurologic examination is normal. His carbamazepine level is therapeutic at 6 mg/dL. Which of the following antidepressants would be least likely to aggravate his seizures?
Sertraline.
ecause of concerns for interaction with hepatically metabolized antiepileptic drugs, first-line therapy using a selective serotonin reuptake inhibitor with minimal effects on the cytochrome P450 isoenzymes (eg, citalopram, escitalopram, sertraline) is preferred. The other drugs listed have been reported to increase the risk of seizure, particularly at higher doses.
A 70-year-old woman has a witnessed cardiac arrest at a shopping center. Cardiopulmonary resuscitation is initiated. When the ambulance arrives
5 minutes later, the rhythm is ventricular fibrillation. After 10 minutes of resuscitation, a pulse is restored. On admission to the intensive care unit (ICU), the patient is comatose with no response to pain. The pupils are 3 mm and sluggishly reactive. Corneal reflexes and oculocephalic responses are reduced. Respiratory and cardiac support is maintained. Twenty-four hours after admission to the ICU, she develops generalized repetitive jerking of muscles
of the face and limbs. An EEG performed at this time is most likely to show which of the following findings?
Burst suppression.
This patient most likely has postanoxic myoclonic status epilepticus (SE), which is usually associated with the EEG finding of burst suppression, characterized by high-voltage bursts of slow, sharp, and spiking activity alternating with a suppressed background. This EEG pattern portends a poor prognosis in postanoxic cerebral injury. The other EEG patterns listed would not be expected to be associated with myoclonic SE.
A 30-year-old woman develops complex partial seizures. An EEG demonstrates left temporal sharp waves, and MRI of the brain shows mild atrophy of the left hippocampal formation. She initially takes levetiracetam but fails to achieve good seizure control. Carbamazepine is added and titrated to a maximum dosage with therapeutic drug levels. Despite this, the patient continues to have disabling seizures. What is the likelihood that addition of a third anticonvulsant will provide adequate seizure control?
10%
This patient has medically refractory epilepsy. Most patients who respond to medical therapy do so with the initial anticonvulsant. In a patient who has failed to achieve good seizure control with monotherapy of two appropriate antiepileptic drugs or a combination of two drugs, the likelihood of response to a third drug is only 5% to 10%. This patient should be evaluated for alternative forms of therapy, including epilepsy surgery.
A 26-year-old businessman presents with a witnessed generalized tonic-clonic seizure in sleep lasting 1 minute, followed by a 20-minute period of confusion. His past medical history is unremarkable. He has no prior history of seizure or head injury. He uses no medications and denies recreational drug use, including alcohol. The patient’s sister had childhood epilepsy. The patient’s neurologic examination is normal. An MRI of the brain with contrast is normal. An awake EEG recording shows no abnormalities. Blood work, including toxicology screen, is normal. Which of the following is the most accurate estimate of this patient’s risk of seizure recurrence in the next 2 years?
40%
atients with a single unprovoked seizure have a recurrence rate of 31% to 56% over 2 to 5 years of follow-up. Factors that increase recurrence risk include the presence of a remote symptomatic etiology, abnormalities on neurologic examination, and the onset of the first seizure during wakefulness. The risk of subsequent seizures is higher after a second seizure (73%) and a third seizure (76%). In this patient, a good argument could be made for not starting anticonvulsants given what is probably a relatively low risk of recurrence. On the other hand, early treatment may be considered in cases where seizure recurrence would have significant consequences related to driving and work.
An 18-year-old college student is evaluated for recurrent episodes of unusual behavior at night. These episodes occur almost weekly, particularly after sleep deprivation or alcohol intake. They occur within 2 to 3 hours of sleep onset. During these episodes he may walk through the dormitory, crawl into someone else’s bed, or be found sitting quietly in the break room. Witnesses report that, during the events, he appears confused and clumsy, his eyes are open, and his speech is soft and slow. He is amnestic from these events upon wakening the next morning. The EEG demonstrates diffuse slowing of the background during the episode. Which of the following is the most likely diagnosis?
Confusional arousal disorder.
The history of nonstereotypic behavior, long duration of the episodes, occurrence during the first half of the night, and amnesia of the events is suggestive of confusional arousal disorder. EEG recording during the event shows exaggerated slowing of background activity. The clinical picture is less likely to be due to nonconvulsive status epilepticus or complex partial seizures and is not consistent with REM sleep behavior disorders or frontal lobe seizures.
A 22-year-old man is evaluated for transient episodes during which he adopts a posture characterized by abduction, elevation, and external rotation of the right arm and deviation of the head toward the right. What is the most likely location of the lesion responsible for these episodes?
Left SMA.
Tonic seizures originating from the supplementary motor area involve abrupt bilateral or asymmetric posturing usually of the contralateral arm, including abduction, elevation, and external rotation associated with contralateral deviation of the head (fencing posture or M2e sign).
A 24-year-old thin woman with temporal lobe seizures due to mesial temporal sclerosis is evaluated for frequent episodes of unresponsiveness despite maximally tolerated doses of carbamazepine. Video-EEG monitoring shows that the episodes of unresponsiveness are associated with ictal discharges in the left temporal region. Which of the following is the preferred drug for adjunctive treatment of seizures in this patient?
LVT
Levetiracetam is the most appropriate choice in this patient. All of the second-generation drugs are indicated for adjunctive therapy of partial seizures and could be considered in this patient, but levetiracetam is the easiest to use in this situation since it is well-tolerated and can be increased quickly. Lamotrigine has a long dose escalation phase to avoid rash. Topiramate has risk of weight loss and a moderately long dose escalation phase. Valproate should be avoided in women of child-bearing potential. Vigabatrin has risk of visual field defects so it is only indicated for partial seizures that have not responded to other appropriate medications.
A 22-year-old woman with medically refractory complex partial seizures who is not a suitable surgical candidate is prescribed vigabatrin. Which of the following adverse effects of the drug should be discussed with the patient?
Irreversible visual field loss.
Vigabatrin is approved by the US Food and Drug Administration for treatment of adults with medically refractory complex partial seizures. The drug may increase the risk of permanent loss of peripheral vision, and patients should be advised to report any vision changes immediately and maintain regular appointments for monitoring visual examinations.
A 6-year-old girl is evaluated at the request of her teacher for possible attention deficit disorder. She was observed by her parents to have transient episodes of abrupt onset of unresponsiveness to external stimuli and behavioral arrest lasting approximately 10 seconds, followed by immediate recovery. She experiences at least 30 such episodes per day. Her neurologic examination is normal. Hyperventilation reproduces the spells. The EEG reveals a generalized 3-Hz spike-and-wave discharge. Which of the following is a feature of this syndrome?
The disorder involves abnormal activation of T-type calcium channels.
The clinical and EEG pictures are typical of childhood absence epilepsy (CAE). Seizures result from activation of T-type calcium channels, leading to abnormally synchronized rhythmic activity in thalamocortical circuits. Calcium channel blockers such as ethosuximide, valproate, and lamotrigine are effective for treatment of absence seizures. In contrast, carbamazepine, oxcarbazepine, and phenytoin should be avoided as they may precipitate absence status epilepticus. Children with early-onset CAE have the best prognosis, with remission of epilepsy 2 to 6 years after onset. Only 3% of children with typical CAE will experience a generalized tonic-clonic seizure during the period of active absences, although up to one-third may develop generalized tonic-clonic seizures in their adolescent or young adult years. CAE may precede juvenile myoclonic epilepsy in 11% to 18% of patients.
A 25-year-old woman with complex partial seizures notes that her seizures occur exclusively at the time of menstruation. She takes carbamazepine and is fully compliant with that medication. Her neurologic examination is normal. MRI of the brain demonstrates left hippocampal atrophy, and EEG shows rare left temporal spikes. Which of the following is most likely responsible for the perimenstrual exacerbation of her seizures?
Decreased progesterone
This patient has catamenial epilepsy, which in her case is most likely a result of progesterone withdrawal with a subsequent increase in estrogen relative to progesterone that occurs at the time of menstruation. Estrogen has proconvulsant properties whereas progesterone and its metabolite allopregnanolone have anticonvulsant properties. Allopregnanolone acts as a positive allosteric modulator of γ-aminobutyric acid A receptors, the main modulators of inhibition in the CNS
A 14-year-old girl has a history of absence seizures beginning at age 6. These are characterized by staring, motor arrest, and fluttering eyelids without loss of postural tone. No other seizure types have been recognized by the family on careful questioning. An EEG shows a 3-Hz spike-and-wave discharge, and an MRI of the head is normal. She has been seizure free on valproic acid for the past 4 years. If the anticonvulsant is tapered, what is the approximate likelihood that she will remain seizure free?
60%
Absence seizures of childhood with the associated 3-Hz spike-and-wave pattern have a high rate of clinical remission in the absence of associated generalized tonic-clonic and myoclonic seizures. The remission rate is up to 60%
A 40-year-old man with a history of generalized convulsive seizures is found dead in his bed by his spouse. His seizures have been suboptimally controlled on monotherapy levetiracetam, a medication with which he was not fully compliant, according to his wife. She reports that he had had three seizures over the past month, but she noted no seizure activity the night of his death. He had not been ill in the days preceding his death. He took no other medications and had consumed two beers the evening preceding his death. His postmortem examination of the brain and other viscera showed no abnormalities other than mild right hippocampal atrophy. Postmortem blood work demonstrated a low levetiracetam level. Which of the following factors placed this patient at highest risk for sudden death?
Uncontrolled convulsive seizures
his patient suffered sudden unexplained death in epilepsy (SUDEP). The cause of SUDEP remains a mystery but is far more common in patients with medically intractable generalized convulsive seizures. Polypharmacy also appears to increase the risk of SUDEP. Poor compliance with antiepileptic drugs (AEDs) and low drug levels have been suspected risk factors, although they have not been consistently shown to increase SUDEP risk. Moreover, the determination of AED levels in postmortem blood samples has been known to be inaccurate. The most important measure to reduce SUDEP risk is optimal control of generalized convulsive seizures with the least number of AEDs possible
A 16-year-old student is evaluated for recurrent spells of lightheadedness followed in many cases by loss of consciousness. The spells tend to occur after prolonged standing or shortly after exercise, particularly in a hot environment. Whereas, in general, she recovers rapidly after hitting the ground, on occasion the loss of consciousness is associated with
generalized stiffening and mild jerking of both upper extremities. The spells may be preceded by excessive sweating, palpitations, nausea, generalized fatigue, and occasionally blurred vision. Which of the following tests is most likely to be abnormal in this patient?
Tilt table test.
The clinical picture is highly suggestive of neurally mediated (reflex, vasovagal, or neurocardiogenic) syncope. The presence of prodromes would be atypical for cardiogenic syncope. Tonic or clonic events (convulsive syncope) reflect brainstem hypoxia rather than seizures. The lack of postictal confusion would be atypical of temporal lobe seizures, although syncope may sometimes be caused by ictal bradycardia. The presence of symptoms of excessive sympathoexcitation (eg, pallor, sweating, palpitations) prior to syncope would be atypical for orthostatic hypotension caused by autonomic failure, and thus plasma catecholamines are not helpful. The short duration of the events and spontaneous recovery would also be atypical for hypoglycemia.
A 55-year-old-man with a history of chronic obstructive pulmonary disease (COPD), hypertension, and complex partial seizures controlled on carbamazepine (CBZ) is evaluated for acute confusion following a respiratory tract infection. Two days ago, he experienced an accidental fall and injured his right elbow. He was prescribed ampicillin, terbutaline, and prednisone to treat the exacerbation of COPD. Propoxyphene was prescribed for elbow pain and eszopiclone for sleep. On examination, he is disoriented and has diplopia, vomiting, and gait ataxia. A plasma carbamazepine level is 15 mg/dL (therapeutic range is 6 mg/dL to 10 mg/dL). Which of the following drugs would be expected to interact and promote acute CBZ toxicity?
Propoxyphene
Propoxyphene inhibits carbamazepine hepatic metabolism through the cytochrome (CYP) 450 isoenzymes and often
results in increasing plasma carbamazepine levels and risk of clinical toxicity.
Other common drug interactions with CYP 3A4 or CYP 2C19 hepatic metabolism that may be relevant include macrolide antibiotics, calcium channel blockers (diltiazem, verapamil), antifungals (fluconazole, ketoconazole), antivirals (indinavir, ritonavir), antidepressants (fluvoxamine, nefazodone), and grapefruit juice
A patient with medically intractable epilepsy is being considered for placement of a vagal nerve stimulator. In counseling the patient, which of the following adverse effects is most likely to result from this device?
Hoarseness
Vagal nerve stimulators (VNS) may be used in the treatment of refractory clinical depression as well as in the treatment of seizure disorders. Vomiting and increased gastric acid secretion are not common side effects of VNS. Hoarseness, throat pain, cough, dyspnea, and paresthesias are relatively common side effects. The VNS is always placed on the left vagal nerve to avoid cardiac complications, which could occur if the right vagal nerve were stimulated
A 70-year-old woman presents to the emergency department after she was found having a generalized tonic-clonic seizure at home. She has no prior history of seizure, and her past medical history is remarkable only for hypertension and hypercholesterolemia. On arrival in the emergency department, she continues to have generalized tonic-clonic seizure activity. Vital signs are heart rate 100 beats/min, blood pressure 160/80 mm Hg, and temperature 37°C. Finger-stick blood glucose level is 85 mg/dL. Which of the following is the most likely cause of status epilepticus in this patient?
Stroke
Cerebrovascular disease (including remote and acute hemorrhagic and ischemic events) accounts for 60% of all cases of status epilepticus in older adults. In this vignette, there is no additional history to suggest neoplasm, and the degree of hypertension is not sufficient to produce seizures. Nothing in the history suggests encephalitis or hypoglycemia