Which clinical feature best distinguishes Major Depressive Disorder (MDD) with psychotic features from MDD without psychotic features?

Explanation

## Distinguishing Feature: Psychotic Symptoms **Key Point:** The hallmark discriminator between MDD with psychotic features and MDD without psychotic features is the presence of delusions or hallucinations that occur exclusively during the depressive episode. ### Defining Characteristics of MDD with Psychotic Features **High-Yield:** In MDD with psychotic features, the psychotic symptoms are **mood-congruent** — they align thematically with the depressive mood state. Common examples include: - Delusions of guilt, worthlessness, or poverty - Delusions of deserved punishment - Nihilistic delusions (e.g., body rotting, being dead) - Hallucinations with depressive content (voices accusing or condemning) **Clinical Pearl:** Mood-congruent psychosis in depression carries a worse prognosis and typically requires combination treatment (antidepressant + antipsychotic), whereas non-psychotic MDD may respond to antidepressant monotherapy. ### Comparison Table: MDD vs. MDD with Psychotic Features | Feature | MDD without Psychosis | MDD with Psychotic Features | | --- | --- | --- | | **Delusions/Hallucinations** | Absent | Present (mood-congruent) | | **Mood Severity** | Mild to severe | Usually severe | | **Vegetative Symptoms** | Present | Present | | **Duration Criterion** | ≥2 weeks | ≥2 weeks | | **Treatment** | Antidepressant monotherapy often sufficient | Antidepressant + antipsychotic required | **Warning:** Do not confuse mood-congruent psychosis in depression with mood-incongruent psychosis (seen in schizophrenia or bipolar disorder), where delusions are unrelated to mood themes. **Mnemonic:** **MCP** = **Mood-Congruent Psychosis** is the defining feature that separates MDD with psychotic features from non-psychotic MDD.