Neuro-Oncology
Anti-LGI1 encephalitis
Oct. 03, 2024
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US Number: +1-619-640-4660
Support: service@medlink.com
Editor: editor@medlink.com
ISSN: 2831-9125
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Alcohol withdrawal seizures are frequently encountered in the emergency room as a severe manifestation of alcohol withdrawal syndrome. Such seizures comprise acute and serious complications to chronic alcohol abuse that need immediate attention. Alcohol withdrawal has been found to be the most common cause of acute symptomatic seizures (74.1%) in one study (52). However, alcohol withdrawal is often neglected as a possible cause of seizures, and the consequences of misdiagnosis include significant morbidity and mortality as well as missing other potentially catastrophic neurologic complications of chronic alcohol dependence such as Wernicke encephalopathy and Korsakoff psychosis. Thus, in addition to benzodiazepines as the first choice in the pharmacological management of such seizures, all such patients should be given thiamine during hospitalization, regardless of nutritional state. In this article, the authors explain the clinical presentation, pathophysiology, diagnostic work-up, and management of alcohol withdrawal seizures and provide clues to the differentiation of withdrawal seizures from seizures due to epilepsy.
• Alcohol withdrawal is a major seizure-precipitating factor. All adult patients arriving to the emergency room with a seizure should be questioned about alcohol intake history. | |
• Drinking history is essential; biomarkers such as GGT and CDT may be useful ancillary aids to diagnosis. | |
• A history of epilepsy prior to alcohol abuse is suggestive of seizures triggered by alcohol abuse instead of alcohol withdrawal seizures and management may vary accordingly. | |
• Existing alcohol-related liver damage is an important consideration in choice of antiepileptic drug treatment. | |
• Benzodiazepines are safe and effective in alleviating both seizures and general withdrawal symptoms as well as preventing further seizures. High initial doses may be necessary, but treatment should be discontinued within a week. Barbiturates have been shown to be effective in acute severe withdrawal syndrome. | |
• Parenteral thiamine should be given before any carbohydrate-containing fluids or food. | |
• The recommended initial preventive thiamine dose is 200 mg; if Wernicke encephalopathy is suspected, give 200 mg three times daily for at least 2 days. | |
• Investigation of first seizures must include neuroimaging. |
The relationship between alcohol and seizures was first mentioned by Hippocrates (39), as well as by the Romans, who even put a name to it, morbus convivialis, or “disorder related to partying” (35). Centuries later, Magnus Huss introduced the term “alcoholismus chronicus” in 1851 and showed that after prolonged intoxication, alcoholics may have seizures (25). He also established that patients with epilepsy who drink must be differentiated from alcohol abusing patients having epileptic seizures during withdrawal (26). In 1953 the first systematic article describing alcohol withdrawal syndrome appeared (76), and later an article exploring the nature of alcohol withdrawal seizures (77). These have remained landmark articles, forming a basis for our current knowledge.
“Alcohol-related seizures” describes all types of interrelationships between seizures and chronic alcohol abuse in adults (50). The occurrence of alcohol-related seizures among individuals admitted with alcohol withdrawal syndrome is about 10% (28). Acute intoxication with alcohol is not a proven cause of seizures (34). On the other hand, situations that are consequent to alcohol abuse and acute withdrawal are where seizures are most often encountered. Alcohol withdrawal seizures are caused by abrupt cessation of heavy alcohol consumption (50). For a comprehensive discussion of seizure types related to alcohol, see McMicken and Liss (42). This article deals only with seizures occurring during alcohol withdrawal in adults.
• Alcohol withdrawal seizures occur 6 to 48 hours after alcohol cessation. | |
• It is characterized by being generalized tonic-clonic, and patients have a nonfocal neurologic examination. |
Alcohol withdrawal seizures are a symptom of early and severe alcohol withdrawal syndrome, usually occurring within 6 to 48 hours of cessation of drinking (76; 77; 27), during which period seizure threshold is reduced (72). Alcohol withdrawal seizures and delirium tremens together complicate about 2.2% of cases of alcohol withdrawal syndrome (28). Alcohol withdrawal seizures typically occur as blood alcohol reaches zero, up to 24 hours after alcohol cessation or with abrupt reduction in intake (42). Although seizures occur in the context of alcohol withdrawal, frequently other signs of alcohol withdrawal syndrome are not present because they develop gradually (27). The seizure type is predominantly the generalized tonic-clonic, occurring singly in about 50% of cases or occurring as a series of seizures within a 6-hour period (77). In principle, patients have a nonfocal neurologic examination and alcohol blood levels must be close to zero g/dL. Other causes of acute symptomatic seizures must be ruled out (see Differential diagnosis), especially if seizures are focal or if status epilepticus develops (51).
Alcohol-related status epilepticus. Status epilepticus is a relatively rare manifestation of alcohol withdrawal seizures, occurring in 4% of these patients (77). Although status epilepticus probably has a better prognosis when alcohol-related compared to many other etiologies (01), it possibly increases the risk for subsequent epilepsy (18). A study that followed a cohort of 257 patients with a first episode of status epilepticus reported that 6.2% of these events were secondary to acute-toxic causes such as drug or alcohol intoxication or withdrawal (33). Acute-toxic causes of status epilepticus had a very low probability of unprovoked seizure recurrence when compared to acute primary central nervous system pathology (ie, stroke, trauma). The estimated risk of seizure recurrence at 1, 2, and 5 years was 0%, 9.1%, and 9.1%, respectively (33). The presence of both status epilepticus and focal seizures should prompt a careful evaluation for structural brain lesions and underlying epilepsy (07).
Delirium tremens. Alcohol withdrawal seizures are a strong risk factor for progression into a severe withdrawal state, with subsequent development of delirium tremens in up to 30% of cases if untreated (77). This is the most severe manifestation of alcohol withdrawal syndrome and progresses 48 to 72 hours after consumption cessation, lasting up to 14 days, with a mortality of 1% (44; 27).
A 62-year-old male with a past medical history of hypertension and alcoholism was brought to the emergency department on a Monday morning with a suspicion of epilepsy. The patient was seen to have a tonic-clonic seizure lasting 3 minutes with lateral tongue trauma after which he was confused and sleepy. According to the patient’s wife, he did not have a known seizure disorder. The patient gradually became responsive in the ER with disorientation in time and place and but had no other focal neurologic abnormalities. Brain CT showed no acute or chronic intracranial lesions, biochemistry panel showed a mild hyponatremia, and toxicological panel was negative, including alcohol levels that were undetectable. The patient was discharged but returned 6 hours later because of two further tonic-clonic seizures that occurred 20 minutes apart. The patient was now tremulous and agitated. The treating physician inquired further into his alcoholism in order to clarify the origin of his seizures, as severe head trauma and metabolic derangements were ruled out and there was no known past medical history of epilepsy. The wife clarified that that he was a heavy drinker and that during the weekend the patient had been drinking continuously for 3 days. He had stopped drinking the night before the seizure occurred. The patient’s Clinical Institute Withdrawal Assessment for Alcohol-Revised (CIWA-Ar [see below]) scale was 14 (71). A diagnosis of alcohol withdrawal seizures was suspected and treated with lorazepam 4 mg as needed, according to the CIWA-Ar. An EEG was performed and interpreted as normal. He was later admitted to a rehabilitation clinic for detoxification. No subsequent seizures were reported at 6-month follow-up appointment.
Alcohol withdrawal seizures develop after chronic alcohol abuse. Case-control studies convincingly demonstrate the association of first seizures to alcohol use in a dose-dependent manner. For example, the risk was 3-fold for people drinking 51 to 100 g alcohol/day and steadily increased to 8-fold and more than 16-fold for people drinking 101 to 200 g/day and more than 200 g/day (47; 36).
Occasionally, seizures are observed after short binges or even single drinking episodes. In such cases, underlying seizure susceptibility is often present, ie, cortical brain damage from trauma, tumors, or epilepsy, and it may be concluded that the alcohol withdrawal state lowered seizure threshold.
Potential mechanisms of alcohol withdrawal seizures have been researched in animals and humans (23). Four mechanisms summarized by Tan and Weaver have been proposed (73):
(1) Chronic intake of ethanol alters fluidity of lipid cell membranes in the brain, affecting interactions between proteins and membrane phospholipids. These changes perturb physiologic function and signal transduction of NMDA, GABA-A, and L-type calcium receptors. It is hypothesized that these changes explain tolerance to alcohol and predispose to a hyperexcitable state when alcohol is withdrawn.
(2) Acute alcohol intake inhibits N-methyl-D-aspartate (NMDA) receptors in a tonic fashion, reducing excitatory glutamatergic synaptic transmission and inhibiting calcium flux through the ion-gated NMDA receptor in a concentration-dependent manner (40; 23). Chronic exposure to alcohol leads to upregulation of NMDA receptor function, increasing NR1, NR2A, and NR2B subunits in hippocampus, cortex, and cerebellum in mice (73). The signs and symptoms of alcohol withdrawal syndrome are thought to reflect this upregulation (14; 23).
(3) Ethanol potentiates GABA-A receptor transmission, increasing chloride influx, similar to benzodiazepines. However, chronic use decreases the number and affinity of GABA-A receptors, altering alpha and delta subunits leading to tolerance (23).
(4) Chronic ethanol intake increases the number of L-type calcium channels in different brain regions. Upregulation of these receptors may explain alcohol dependence and hyperexcitability.
Chronic adaptations in these receptors induce tolerance and dependence during active ethanol abuse. The combination of these mechanisms leads to a hyperexcitable neuronal state during withdrawal episodes because upregulation of NMDA receptors and L-type Ca++ receptors increases influx of calcium in neurons, concurrently leading to membrane depolarization and excitotoxicity. As GABA-A receptors are downregulated, a hyperexcitable state develops, leading to lowered seizure threshold and to acute withdrawal seizures when the patient abruptly ceases alcohol intake. Of note, repeated episodes of alcohol withdrawal seizures may lead to a kindling-like phenomenon (34). Other mechanisms proposed include: homocysteine increase (through stimulation of NMDA receptors), acting as an excitatory neurotransmitter and possible biomarker in active drinking patients; polymorphisms in dopamine transporter gene, with changes in these gene related to greater susceptibility to severe alcohol withdrawal syndrome and seizures; and apolipoprotein E allele 3 possibly associated with a history of alcohol withdrawal seizures (23).
It is estimated that 50% of persons with alcohol-use disorders experience symptoms of alcohol withdrawal when they reduce or discontinue their alcohol consumption (67). Up to 15% of individuals with alcohol-use disorder at some stage will suffer a seizure (10), and alcohol withdrawal is a common cause of adult-onset seizures (42). Of all alcohol-related seizures, 30% to 39.3% are related to alcohol withdrawal (51). Severe alcohol withdrawal syndrome accounts for 8% of inpatients with alcohol abuse disorders, with seizures and delirium tremens doubling inpatient stay and frequently requiring admission to the ICU (27). The history of previous alcohol-related seizures increases the odds of experiencing seizures in individuals hospitalized with alcohol withdrawal syndrome (28). However, there is no clear causal relationship between alcohol consumption and epilepsy (80). In addition, the presence of alcohol withdrawal seizures increases the probability of delirium tremens (28). Interestingly, an increase in the proportion of hospital visits due to alcohol withdrawal seizures during the first year of COVID-19 pandemic was observed in New York City, relative to a decrease in the total visits for alcohol use (66).
Primary seizure prevention. When a patient is hospitalized for symptoms of alcohol withdrawal, the question arises as to whether treatment aims should include prevention of seizures. Patients with mild-to-moderate alcohol withdrawal symptoms (CIWA scale < 10) and no history of alcohol withdrawal seizures can successfully be detoxified with supportive care only (78). Supportive treatment includes a calm, reassuring atmosphere, coffee restriction, daylight views, and hydration.
Patients with severe alcohol withdrawal symptoms and all those with seizures during previous alcohol withdrawal episodes have higher risk for alcohol withdrawal seizures and may benefit from seizure preventive treatment (20). When pharmacological treatment is necessary, benzodiazepines should be chosen for the primary prevention of seizures in a person with alcohol withdrawal. The drugs of choice are lorazepam and diazepam.
Secondary seizure prevention. Following an alcohol withdrawal seizure, the recurrence risk within the same withdrawal episode is 13% to 24% (20). In addition, history of an alcohol withdrawal seizure and a seizure during the concurrent withdrawal episode are associated with increased risk of complications and progression to alcohol withdrawal delirium and should be treated as an inpatient (79). Consequently, there is good rationale for treating these patients as soon as possible in order to prevent subsequent seizures. It is a common mistake to attribute repeated withdrawal seizures to epilepsy and start treatment with antiepileptic drugs. In fact, a Cochrane review of 56 studies (n= 4076) found no convincing evidence in favor of using antiseizure medications in patients with alcohol withdrawal (43). Additionally, poor compliance, no treatment effect, and risk of drug interaction problems can be expected in such cases (19).
Differential diagnosis. Potential alternative diagnoses should be ruled out in an adult with a first episode of alcohol-related seizures (51; 42):
• Withdrawal seizures from chronic drug abuse (benzodiazepines, barbiturates) | |
• Uncontrolled epilepsy, including noncompliance to antiseizure medication and pharmaco-resistance | |
• Acute intoxication with drugs such as amphetamines, anticholinergics, cocaine, isoniazid, organophosphates, tricyclic antidepressants, or salicylates | |
• Life-threatening metabolic disorders (hypoglycemia, hyponatremia, hypernatremia, hypocalcemia, hypomagnesemia) | |
• Infections (meningitis, encephalitis, systemic) | |
• Significant head trauma, past or current | |
• Intracranial hemorrhage (subarachnoid, intraparenchymal, subdural hematoma, epidural hematoma) | |
• Acute ischemic stroke | |
• Nontraumatic intracranial lesions (tumors, gliosis) | |
• Convulsive syncope | |
• Psychogenic nonepileptic events |
The first consideration in a patient with possible alcohol withdrawal seizures is the exclusion of life-threatening causes of seizures, as described in the differential diagnoses above (42). At the same time, a history of chronic alcohol abuse must be sought and the patient should be classified as having one of the categories of alcohol-related seizures (42). As more than 90% of alcohol withdrawal seizures occur soon after the cessation of sustained drinking, whereas other withdrawal symptoms develop gradually, withdrawal may not be readily evident in the beginning (27).
Physical examination. The patient should be checked for other signs of alcohol withdrawal such as tachycardia, tachypnea, mydriasis, elevated blood pressure, hyperthermia, diaphoresis, and tremor, among others (27). In addition, perform a neurologic examination to determine possible etiology (79). Clinical features distinctive of either epilepsy or alcohol withdrawal seizures should be delimited (05). In case of epilepsy, postictal symptoms may prevail. Most patients with epilepsy will be drowsy or in postictal coma. In contrast, patients in a withdrawal state frequently manifest other symptoms like tremor, anxiety, irritability, delirium, and agitation. In most cases, clinical signs and symptoms distinctive of alcohol withdrawal syndrome will develop shortly and evolve gradually (within 24 hours) after the seizure and the patient should be observed for such symptoms. The length of time required for observation is not recommended in the current literature and should be determined on an individual basis.
Electrocardiogram. Alcohol withdrawal may increase risk of sudden death because it may prolong QT interval, the reason why EKG should be performed in patients presenting with alcohol withdrawal seizures or alcohol-related seizures (34).
Biomarkers. For detection of alcohol overuse, questionnaire-based interviews are reported to be more sensitive than any biomarker (04). However, in cases where information on recent alcohol consumption is unavailable or considered unreliable, markers of alcohol consumption can increase accuracy of clinical diagnosis (06; 08). Carbohydrate-deficient transferrin (CDT) and gammaglutamyl transferase (GGT) are sensitive markers for alcohol overuse; systematic literature reviews have been inconclusive as to which marker is better (59; 68). No biomarker can be recommended for screening of unselected seizure populations (06; 08).
As the current intoxication level is important information with potential treatment consequences, blood alcohol concentration should be measured in patients with suspected alcohol-related seizures (64). Urinary ethyl glucuronide and ethyl sulfate have been reported to have high sensitivity and specificity for recent drinking (11; 70).
Neuroimaging. It is recommended to rule out structural causes of seizures in patients with a first seizure, status epilepticus, or in patients where head trauma is suspected (27). A CT scan of the brain suffices in the acute setting, although an MRI is preferable if there is a question of an underlying epilepsy. Seizures that occur later than 48 hours after intake of the last drink may indicate other potential etiologies than simple alcohol withdrawal, such as subdural hematoma, brain contusion, or mixed drug and alcohol overuse (19). When patients present repeatedly with typical alcohol withdrawal seizures, imaging is not necessary unless changes in seizure type and frequency, seizure occurrence more than 48 hours after cessation of drinking, or other unusual features are present.
Electroencephalography (EEG). Inpatient EEG should be recorded after a first seizure, if status epilepticus is suspected, or if a new seizure pattern emerges (27). Yet the value of EEG in the setting of alcohol withdrawal seizures is limited and findings such as epileptiform activity should prompt the evaluation of an underlying epilepsy (23). In addition, where repeated withdrawal seizures are a pattern, EEG is considered necessary only if an alternative etiology is suspected. The incidence of EEG abnormalities (focal slowing or epileptiform activity) is lower among patients with alcohol withdrawal seizures than in those with seizures of other etiologies. Therefore, an abnormal EEG suggests that the seizure may not have been caused exclusively by alcohol withdrawal (60).
Monitoring. Because a patient is at risk of seizure recurrence and progression to delirium after an alcohol withdrawal seizure, patients should be admitted for close monitoring with a frequency of 1 to 2 hours for the first 6 to 24 hours. Those experiencing moderate to severe withdrawal should be monitored every 1 to 4 hours or as clinically indicated with a validated withdrawal severity scale (79). In addition, “patient’s vital signs, hydration, orientation, sleep, and emotional status including suicidal thoughts” should be regularly monitored (79). If patient’s symptoms are controlled (CIWA-AR scores < 10) for 24 hours, monitoring intervals can increase to every 4 to 8 hours. Patients receiving benzodiazepines and other forms of pharmacotherapy should be monitored for respiratory depression and over sedation (79). Nonpharmacological measures like reorientation and reassurance should be frequently provided.
Acute drug treatment. Because alcohol withdrawal seizures are a symptom of severe acute withdrawal syndrome, they should be treated as such. Patients should be admitted and close monitoring should be available, assessing the patient every 1 to 2 hours for up to 6 to 24 hours (79). As mentioned above, the revised CIWA-Ar scale can be applied to grade the severity of alcohol withdrawal (71). It has prognostic value, as patients with scores less than 10 generally do not need pharmacological treatment. However, symptom-triggered therapy based on the CIWA-Ar protocol depends on correct application of the inventory (17). A metaanalysis of 30 randomized controlled trials compared benzodiazepines versus non-benzodiazepines treatment for alcohol withdrawal syndrome (15). Results from this analysis on tapering methods favored antiseizure medications (gabapentin and carbamazepine) over benzodiazepines (chlordiazepoxide, lorazepam, and oxazepam) for reducing CIWA-Ar scale scores.
Benzodiazepines. Benzodiazepines have been the preferred drug class and are standard of care (02; 46). Guidelines recommend benzodiazepines as first line of treatment (79). They should be given parenterally following a withdrawal seizure to prevent another seizure and the occurrence of delirium (79). In comparison to other medications, this group of GABA-ergic medications has been shown to reduce severity of withdrawal symptoms, prevent appearance of delirium tremens, status epilepticus, and recurrent seizures, and at the same time provide safety and low abuse potential (13; 20; 02). In fact, an overview of systematic reviews in Cochrane provides moderate evidence that benzodiazepines perform better than any other treatment, compared to placebo, in preventing alcohol withdrawal seizures (RR 0.16 [95%CI 0.004-0.69]) (02). A network metaanalysis comparing different pharmacotherapies in 10,692 patients reported a reduction of incident alcohol withdrawal seizures with fixed schedule diazepam, lorazepam, and chlordiazepoxide when compared to placebo (03). In addition, it concluded that benzodiazepines were the most extensively studied and “the only agents showing consistent efficacy across efficacy, safety, acceptability, and secondary outcome measures” (03). Although a metaanalysis of alternative options for management concluded that non-benzodiazepine medications are superior or equally effective as benzodiazepines in managing alcohol withdrawal syndrome, the prevalence of seizures as a side effect was higher in the non-benzodiazepine group (gabapentin, propranolol) compared to the benzodiazepine group (15).
In a meta-analysis of controlled trials for prevention of alcohol withdrawal seizures, a highly significant risk reduction for seizures with benzodiazepines compared to placebo was demonstrated (20). For the purpose of reducing risk of seizures and rebound withdrawal symptoms after discontinuation, long-acting drugs should be preferred to short-acting ones (41; 20). However, short-acting benzodiazepines may have advantages for patients with respiratory insufficiency. Symptom-triggered treatment has been reported to be as effective as fixed-dose or loading therapy, resulting in lower doses and shorter treatment time (58). Yet, treatment strategies and doses vary from center to center and consensus is lacking (46).
Lorazepam has some advantages over diazepam. Despite a shorter half-life it has longer duration of action because it is distribution is slower and less extensive (13). However, its onset of action is slightly slower than that of diazepam. In a study that compared lorazepam versus diazepam, no differences were seen in seizure recurrence and other parameters such as readmission, CIWA-Ar score, or length of stay (65).
When loading with a benzodiazepine, it is important to monitor the patient for signs of over-sedation and respiratory depression (79).
Barbiturates. Phenobarbital has a longer half-life than benzodiazepines and has the pharmacodynamic advantage of acting on both GABA and glutamate (24). Studies have assessed use of barbiturates in the treatment of alcohol withdrawal syndrome. There has been a general concern that phenobarbital may have an increased risk of sedation prompting invasive mechanical ventilation (49). A metaanalysis compared phenobarbital versus benzodiazepines for alcohol withdrawal syndrome in the emergency department and/or intensive care unit (49). Twelve studies were included (1934 subjects) concluding that phenobarbital did not increase the risk of intubation, and the frequency of seizures was similar between both groups. A systematic review of clinical trials considered seven studies using barbiturates versus benzodiazepines for the treatment of acute withdrawal syndrome (44). In their analysis, the authors concluded that for patients with severe alcohol withdrawal syndrome, benzodiazepines with barbiturates may control symptoms in an additive fashion. They also indicated that barbiturates have the potential of treating patients who become refractory to benzodiazepines. An observational cohort study compared a fixed-dose phenobarbital protocol versus as-needed benzodiazepine regimen in subjects with high-risk alcohol withdrawal in one institution (24). Although end points were not significantly different between both cohorts, no seizures were reported in the phenobarbital cohort even though this group had a higher proportion of subjects with history of complicated withdrawal (seizures and delirium tremens). The protocol of phenobarbital was composed of a load tailored according to the patient’s risk of sedation followed by down-titration of PO doses. The combination of benzodiazepines with phenobarbital (single intravenous dose of 10 mg/kg) may also prevent ICU admission and ventilation, with a similar safety profile in comparison to benzodiazepines alone (56). Similar to benzodiazepines, dose regimens vary from study to study with phenobarbital (44). A retrospective cohort study comparing use of CIWA-Ar-guided benzodiazepine protocol versus scheduled intramuscular phenobarbital in patients with severe alcohol withdrawal reported significant decrease in length of stay (30). Parenteral phenobarbital should be used with caution and in a setting with frequent supervision due to the risk of sedation and respiratory depression (79). Phenobarbital has not been approved by the Food and Drug Administration for alcohol withdrawal. Further research with large randomized clinical trials with standardized phenobarbital protocols are needed because evidence for treatment comes mainly from observational studies (49). Studies focusing on alcohol withdrawal seizures as the main outcome are lacking (62).
Antiseizure medication and other drugs. Historically, antiseizure medications have been used in the treatment and prevention of seizures in alcohol withdrawal syndrome. Some antiseizure drugs and drug combinations are used, including phenytoin, carbamazepine, oxcarbazepine, gabapentin, chlormethiazole, sodium valproate, gamma-hydroxybutyrate, and clonidine, for all of which evidence is generally poor (54; 58; 21; 20; 43). Recently, three published metaanalyses have evaluated the prevention and treatment of alcohol withdrawal seizures with antiseizure medications in comparison with placebo or with benzodiazepines and/or phenobarbital. A 2021 metaanalysis including 24 studies and 2223 subjects reported no improvement in prevention of seizures or delirium tremens with antiseizure medications as first-line agents, even when compared to placebo (31). Moreover, subjects who received antiseizure medications had three-fold increased odds of requiring rescue medication when compared to benzodiazepines and tolerability was similar in both groups (31). A network metaanalysis reported that sodium valproate was superior to placebo in decreasing incident alcohol withdrawal seizures (03). This study indicated an improvement in CIWA-AR scores with oxcarbazepine and carbamazepine when compared to placebo yet no significant differences in the prevention of seizures (03). However, carbamazepine was associated with greater dropouts due to adverse events. Another metaanalysis, including 1709 subjects from 26 studies of small sample size, originating mainly from specialized, nonacute settings reported that the incidence or recurrence of alcohol withdrawal seizures did not differ significantly between treatment with antiseizure medication and placebo or usual treatment (benzodiazepine or phenobarbital) (55). These three metaanalyses, which are based on low quality evidence, suggest that the clinical use of antiseizure medications as first-line treatment in alcohol withdrawal syndrome and related seizures cannot be supported, and these medications should not replace benzodiazepines as first-line treatment. In addition, there is no evidence that antiseizure medications can prevent delirium tremens, an important complication of alcohol withdrawal (03).
Alpha2-adrenergic agonists like clonidine and dexmedetomidine should not be used alone to prevent alcohol withdrawal seizures or delirium as they “do not treat the underlying pathophysiology” (79). These medications may be used as adjunctive therapy with benzodiazepines in the treatment of anxiety or autonomic hyperactivity that persist in spite of benzodiazepine use, as a benzodiazepine-sparing treatment for alcohol withdrawal syndrome in the ICU (79). A metaanalysis based on low- to very low-quality evidence evaluating cohort studies and randomized trials in the ICU concluded that adjunctive dexmedetomidine showed no significant difference in ICU length of stay or total benzodiazepine requirements, with an increase in adverse effects like bradycardia and hypotension, when compared to benzodiazepines alone (48). Paradoxically, length of stay in the meta-analysis favored standard benzodiazepine therapy when analyzing cohort studies, but dexmedetomidine adjunctive therapy was significantly favored when randomized controlled trials were analyzed. Data on dexmedetomidine use are limited in alcohol withdrawal syndrome, and conflicting results require further investigation with randomized controlled trials. A Cochrane review of studies using baclofen for acute withdrawal syndrome found very low-quality evidence and no greater efficacy when compared to placebo, diazepam, and chlordiazepoxide (38). Seizure risk and delirium were not assessed as outcomes, and the reviewers concluded that there was insufficient and very low-quality evidence to draw any conclusions (38). In addition, alpha 2-adrenergic agonists (clonidine), beta-blockers, or dexmedetomidine should not be used in the prevention or treatment of alcohol-withdrawal seizures (79).
Seizures. Acute seizure treatment should follow standard protocol, ie, repeated doses of a benzodiazepine (preferably lorazepam or diazepam) until seizures stop. If ineffective (alcohol-related status epilepticus), sodium valproate should be considered before fosphenytoin/phenytoin, as phenytoin has been shown to be ineffective in preventing recurrent seizures in three controlled studies (20).
Thiamine therapy. Due to risk of developing Wernicke-Korsakoff syndrome, which is often underdiagnosed and may lead to permanent brain damage, patients presenting with known or suspected alcohol overuse should be given thiamine parenterally in the emergency room, before starting any carbohydrate-containing fluids or food. The optimal dose is not settled, but because parenteral thiamine administration is generally safe, diagnosis of thiamine deficiency is difficult, and potential consequences of not treating are devastating; erring on the side of caution with liberal dosing is to be recommended. Prophylactic therapy is recommended in all patients with known or suspected alcoholism, malnutrition, or frequent vomiting. According to a Cochrane review, there is insufficient evidence to guide the selection of dose, frequency, route, or duration of thiamine for prophylaxis or treatment of Wernicke-Korsakoff syndrome (12). Parenteral administration of 250 mg thiamine should be given in the emergency room before any carbohydrates are started to prevent Wernicke-Korsakoff syndrome, and this dose should be continued daily for 3 to 5 consecutive days (69). Oral administration is insufficient, as the intestinal thiamine absorption is too low and may be severely impaired in alcohol abuse (22).
When Wernicke encephalopathy is suspected or manifests, parenteral administration of 500 mg thiamine three times daily should be started with no delay, as recommended by British guidelines (category D) (37). Intravenous infusion of thiamine diluted with 100 ml saline or 5% glucose, given over 30 minutes is recommended (16). The treatment should continue for at least 3 to 5 days. Then a dose of 250 mg of thiamine should be continued once daily for 3 to 5 days depending on response (37). Patients with manifest Wernicke-Korsakoff syndrome may benefit from a treatment period of up to 2 weeks. It has been speculated that patients who are in a catabolic state or under the influence of alcohol have reduced ability to store thiamine because enzymes depending on thiamine are downregulated or protein binding is altered by the influence of alcohol (16). In such cases, early reinstitution of a normal diet may be important.
Electrolyte disturbances. Hyponatremia in alcohol abusers generally shows a benign clinical course, and usually corrects with cessation of alcohol intake and re-institution of a normal diet (29). The serious disorder of central pontine myelinolysis is thought to be triggered by osmotic gradients in the pons, a situation that might result from attempts to correct electrolyte disturbances too rapidly (32). If parenteral treatment is considered necessary, according to a retrospective study, the rate of serum sodium correction should not exceed 10 mmol/l per day (57).
Hypomagnesemia and respiratory alkalosis seem to be associated with alcohol withdrawal, and correction of hypomagnesemia may raise the seizure threshold in the initial phase of alcohol withdrawal (75). It has been speculated that unresponsiveness to parenteral thiamine therapy may result from hypomagnesemia (74). Despite the theoretical benefit, there is not sufficient evidence to recommend magnesium supplement, as demonstrated by a Cochrane systematic review (63).
Alcohol withdrawal syndrome is associated with poor clinical outcomes and with an in-hospital mortality that ranges from 2% to 7% (45; 09). Severe alcohol withdrawal syndrome (including seizures) increases 12 times the risk of long-term mortality when compared to a control population (adjusted hazard ratio of 12.7; 95% CI 8.9-17.5) (09). A retrospective single-center study conducted in the emergency department evaluated the risk factors for recurrence of alcohol withdrawal seizures after an event of alcohol withdrawal seizure (62). Eleven percent of the patients had recurrence of seizures after index event with a median follow-up of almost 5 years and a median time from index event to relapse of 1.3 years. The following were risk factors for relapses: history of previous alcohol withdrawal seizures, skull fractures at the index event, and epileptiform EEG abnormalities. Treatment with benzodiazepines or antiseizure medication was not associated with decrease in recurrence risk. In addition, mortality after an index event of alcohol withdrawal seizures was 13 times higher compared to the general population (2.9% per year of follow-up) (62). A history of alcohol withdrawal seizures prior to index event increased the mortality risk (hazard ratio of 4). Obtaining a CT scan of the brain and an EEG is suggested by the authors of this study to evaluate for risk of recurrence.
Alcohol is teratogenic. Fetal alcohol spectrum disorders are more prevalent than previously recognized and cause a wide range of birth defects and neurodevelopmental disorders (53). There is no current evidence that alcohol-related seizures confer additional maternal or fetal risk, over and above those of alcohol abuse and seizures independently. A pregnancy test should be performed in all women of childbearing age with alcohol withdrawal (79). However, results should not delay the appropriate treatment. Pregnant patients should be admitted to the inpatient setting if they require withdrawal management, and an obstetrician should be consulted (79). The CIWA-Ar scale is appropriate for monitoring, and benzodiazepines and barbiturates are the treatment of choice in these patients (79).
Newborns whose mothers are intoxicated prior to or during delivery can experience withdrawal symptoms, such as tremors and even seizures. It is likely that withdrawal also can occur during fetal development. Thus, repeated withdrawals during pregnancy may pose an additional risk to the fetus from that of alcohol exposure in itself. Pregnant women should refrain from drinking alcohol.
During alcohol withdrawal, patients may require higher than normal doses of GABAergic substances (benzodiazepines).
Concurrent mental health conditions. A primary mental health disorder should not be diagnosed during the acute withdrawal period, as signs and symptoms may overlap (anxiety, sleeping disturbance, agitation) (79). However, screening questionnaires such as the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder (GAD-7) may help orient a diagnosis when feasible and are recommended in the guidelines (79). Always review the patient’s medical record and past medical history for mental health diagnosis. It is important to evaluate for suicide risk in every patient during the initial assessment (79).
Concomitant substance abuse should be identified as substances such as sedatives may modify symptom presentation and affect response to treatment of alcohol withdrawal. The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), developed by the World Health Organization is recommended for the identification of polysubstance abuse (79).
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