A 52-year-old man with a 20-year history of alcohol dependence presents to the emergency department with tremors, diaphoresis, tachycardia, and agitation 36 hours after his last drink. He is confused and has visual hallucinations. Which investigation is most appropriate to confirm the diagnosis of alcohol withdrawal and assess severity?

Explanation

## Investigation of Choice in Alcohol Withdrawal **Key Point:** The Clinical Institute Withdrawal Assessment for Alcohol Scale (CIWA-Ar) is the gold-standard validated tool for diagnosing and quantifying the severity of alcohol withdrawal syndrome. It does not require laboratory confirmation and can be administered at the bedside. ### Why CIWA-Ar is the Best Choice The CIWA-Ar is a 10-item scale that assesses: - Tremor - Sweating - Anxiety - Agitation - Tactile, auditory, and visual disturbances - Headache - Orientation **High-Yield:** Scores ≥15 indicate severe withdrawal and risk of seizures or delirium tremens; scores <10 suggest mild withdrawal. This guides intensity of pharmacological intervention (benzodiazepine dosing). **Clinical Pearl:** The presence of visual hallucinations in this patient (36 hours post-cessation) is consistent with alcoholic hallucinosis, a form of alcohol withdrawal that falls on the spectrum of withdrawal severity. CIWA-Ar quantifies this severity objectively. ### Why Other Investigations Are Not First-Line | Investigation | Role | Limitation in Withdrawal Diagnosis | |---|---|---| | Liver function tests & PT | Assess hepatic synthetic function and complications | Detects liver disease but NOT withdrawal syndrome; non-specific | | Serum ethanol level | Confirms recent alcohol use | Ethanol level does NOT correlate with withdrawal severity; withdrawal occurs as level *falls*, not when high | | EEG with photic stimulation | Detects seizure activity or abnormalities | Used if seizures occur; not diagnostic for withdrawal; not routine | **Warning:** Do not confuse the need to check LFTs (which is important in chronic alcohol use to rule out cirrhosis) with the need to diagnose withdrawal. LFTs are supportive investigations, not diagnostic. **Mnemonic:** **CIWA-Ar** = **C**linical **I**nstitute **W**ithdrawal **A**ssessment for **A**lcohol scale—**r**evised. It is the bedside clinical tool of choice.