Table 2.
Differential Diagnosis of Catatonia.
| Diagnosis | Similarities to catatonia | How it differs from catatonia |
|---|---|---|
| Neuroleptic malignant syndrome | Vital sign instability | Requires exposure to newly started dopaminergic agent, or recent change in dose |
| Altered mental status | ||
| Low serum iron | ||
| Elevated CPK | ||
| Serotonin syndrome | Altered mental status | GI distress |
| Rigidity | Hyperreflexia | |
| Vital sign instability | Clonus | |
| Delirium | Hypoactive and hyperactive types | Worsened by benzodiazepines |
| Decreased attention | ||
| Withdrawal from environment | Other psychomotor abnormalities (echolalia, echopraxia, rigidity, etc.) not present | |
| Coma | Hypoactivity | Reflexes lost in coma |
| Mutism | Parakinetic symptoms not present | |
| Incontinence | No response to benzodiazepine challenge | |
| Extrapyramidal side-effects (EPS) | Akathisia | No altered mental status |
| Dystonia (may look like rigidity or posturing) | No other motor symptoms present; no impaired volition | |
| No negativism | ||
| Hypoactivity not present | ||
| Parkinsonism | Rigidity | No other motor symptoms present |
| Motor freezing | Tremor present in Parkinsonism | |
| Staring | Patients generally interactive | |
| Status epilepticus | Immobility | Specific EEG findings |
| Withdrawal |