The levels of evidence (class I-IV) supporting the recommendations and ratings of recommendations (A-C, Good Practice Point [GPP]) are defined at the end of the "Major Recommendations" field.
Diagnosis of Alcohol-Related Seizures
History Taking
A good drinking history includes both the quantity and frequency of alcohol intake and changes in drinking pattern, at least during the previous five days, as well as the time of the last alcohol intake (GPP).
Questionnaires
Questionnaires offer high diagnostic accuracy for alcohol overuse (level A recommendation). To identify patients with alcohol-related seizures and binge drinking, brief versions of the Alcohol Use Disorders Identification Test (AUDIT) are recommended as they are accurate and easy to use in busy clinical settings (level A recommendation).
Biomarkers
Carbohydrate-deficient transferrin (CDT) and gammaglutamyl transferase (GGT) have a potential to support a clinical suspicion of alcohol overuse when the drinking history is inconclusive (level A recommendation). Due to poor accuracy in unselected populations, biomarkers should not be applied as general screening instruments (level C recommendation).
As the current intoxication level is important information with potential treatment consequences blood alcohol should be measured in patients with suspected alcohol-related seizures (GPP).
Patient Examination and Observation
More than 90% of alcohol withdrawal seizures occur within 48 hours of cessation of a prolonged drinking bout. Patients should be observed in hospital for at least 24 hours, after which a clinical risk assessment should be made with respect to development of symptoms of alcohol withdrawal (GPP).
The Clinical Institute Withdrawal Assessment (CIWA) questionnaire can be applied to grade the severity of withdrawal symptoms and give support to the decision on whether to keep or discharge the patient (level A recommendation).
Neuroimaging
Although it may seem obvious that a given seizure is alcohol-related, if it is a first known seizure, the patient should have brain imaging (computed tomography [CT] or magnetic resonance imaging [MRI]) without and with contrast (level C recommendation).
When patients present repeatedly with clinically typical alcohol-related seizures, re-imaging is not necessary, but changes in seizure type and frequency, seizure occurrence more than 48 hours after cessation of drinking, or other unusual features should prompt repeat neuroimaging (GPP).
Electroencephalography (EEG)
EEG should be recorded after a first seizure. Subsequent to repeated alcohol withdrawal seizures (AWS), EEG is considered necessary only if an alternative aetiology is suspected (level C recommendation).
Patient Management
Thiamine Therapy
Before starting any carbohydrate containing fluids or food, patients presenting with known or suspected alcohol overuse should be given prophylactic thiamine in the emergency room (level B recommendation).
For the treatment of imminent or manifest Wernicke's encephalopathy, uncontrolled trials and empirical clinical practice suggest a daily dose of at least 200 mg thiamine parenterally for minimum 3 to 5 days. In the guideline developers' experience, patients with Wernicke's encephalopathy may benefit from continued treatment for more than two weeks (GPP).
Should All Patients with Symptoms of Alcohol Withdrawal Be Offered Seizure Prophylactic Treatment?
For patients with no history of withdrawal seizures and mild to moderate withdrawal symptoms, routine seizure preventive treatment is not recommended (level B recommendation). Patients with severe alcohol withdrawal symptoms, regardless of seizure occurrence, should be treated pharmacologically (level C recommendation).
Drug Options for Primary Prevention of Alcohol Withdrawal Seizures
When pharmacological treatment is necessary, benzodiazepines should be chosen for the primary prevention of seizures in a person with alcohol withdrawal, as well as for treatment of the alcohol withdrawal syndrome. The drugs of choice are lorazepam and diazepam. Although lorazepam has some pharmacological advantages to diazepam, the differences are minor and, as intravenous (i.v.) lorazepam is largely unavailable in Europe, diazepam is recommended. Other drugs for detoxification should only be considered as add-ons (level A recommendation).
Secondary Prevention of Withdrawal Seizures
Benzodiazepines should be used for the secondary prevention of AWS (level A recommendation). Phenytoin is not recommended for prevention of AWS recurrence (level A recommendation). The efficacy of other antiepileptics for secondary prevention of AWS is undocumented.
Alcohol-Related Status Epilepticus
For the initial treatment of alcohol-related status epilepticus, i.v. lorazepam is safe and efficacious. When unavailable, i.v. diazepam is a good alternative (level A recommendation).
How Much Alcohol Can a Patient with Epilepsy Safely Consume?
For the majority of patients with partial epilepsy and controlled seizures, and in the absence of any history of alcohol overuse, an intake of 1 to 3 standard alcohol units, 1 to 3 times a week, is safe (level B recommendation).
Definitions:
Evidence Classification Scheme for a Diagnostic Measure
Class I: A prospective study in a broad spectrum of persons with the suspected condition, using a "gold standard" for case definition, where the test is applied in a blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy
Class II: A prospective study of a narrow spectrum of persons with the suspected condition, or a well-designed retrospective study of a broad spectrum of persons with an established condition (by "gold standard") compared to a broad spectrum of controls, where test is applied in a blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy
Class III: Evidence provided by a retrospective study where either persons with the established condition or controls are of a narrow spectrum, and where test is applied in a blinded evaluation
Class IV: Any design where test is not applied in blinded evaluation OR evidence provided by expert opinion alone or in descriptive case series (without controls)
Evidence Classification Scheme for a Therapeutic Intervention
Class I: An adequately powered prospective, randomized, controlled clinical trial with masked outcome assessment in a representative population or an adequately powered systematic review of prospective randomized controlled clinical trials with masked outcome assessment in representative populations. The following are required:
- Randomization concealment
- Primary outcome(s) is/are clearly defined
- Exclusion/inclusion criteria are clearly defined
- Adequate accounting for dropouts and crossovers with numbers sufficiently low to have minimal potential for bias
- Relevant baseline characteristics are presented and substantially equivalent among treatment groups or there is appropriate statistical adjustment for differences
Class II: Prospective matched-group cohort study in a representative population with masked outcome assessment that meets a–e above or a randomized, controlled trial in a representative population that lacks one criteria a–e
Class III: All other controlled trials (including well-defined natural history controls or patients serving as own controls) in a representative population, where outcome assessment is independent of patient treatment
Class IV: Evidence from uncontrolled studies, case series, case reports, or expert opinion
Rating of Recommendations for a Diagnostic Measure
Level A rating (established as useful/predictive or not useful/predictive) requires at least one convincing class I study or at least two consistent, convincing class II studies.
Level B rating (established as probably useful/predictive or not useful/predictive) requires at least one convincing class II study or overwhelming class III evidence.
Level C rating (established as possibly useful/predictive or not useful/predictive) requires at least two convincing class III studies.
Rating of Recommendations for a Therapeutic Intervention
Level A rating (established as effective, ineffective, or harmful) requires at least one convincing class I study or at least two consistent, convincing class II studies.
Level B rating (probably effective, ineffective, or harmful) requires at least one convincing class II study or overwhelming class III evidence.
Level C rating (possibly effective, ineffective, or harmful) requires at least two convincing class III studies.
Good Practice Points (GPPs) Important aspects of patient management lacking the evidence required for making a recommendation were marked good practice points.