Differential Diagnosis for a Patient Not Meeting Full DSM 5TR Criteria for Major Depressive Disorder (MDD)

Single Most Likely Diagnosis

• Persistent Depressive Disorder (Dysthymia): This diagnosis is considered when a patient experiences a depressed mood for most of the day, more days than not, for at least two years, but the symptoms do not meet the full criteria for a major depressive episode.
• Subthreshold Depression: This condition is characterized by depressive symptoms that do not meet the full diagnostic criteria for MDD but still cause significant distress or impairment.

Other Likely Diagnoses

• Adjustment Disorder with Depressed Mood: This diagnosis applies when a patient experiences depressive symptoms in response to a specific stressor, and the symptoms or behavior are clinically significant but do not meet the criteria for MDD.
• Bipolar Disorder (Hypomanic or Cyclothymic Specifier): Although the patient may not meet the full criteria for MDD, they might experience periods of hypomania or cyclical mood swings that do not reach the threshold for a manic episode.
• Anxiety Disorders: Many anxiety disorders, such as generalized anxiety disorder or panic disorder, can present with depressive symptoms that do not meet the full criteria for MDD.

Do Not Miss Diagnoses

• Bipolar Disorder with Mixed Features: It's crucial to assess for manic or hypomanic symptoms, even if they are not immediately apparent, as missing this diagnosis can lead to inappropriate treatment with antidepressants, potentially inducing mania.
• Postpartum Depression: In postpartum women, depressive symptoms might not fully align with MDD criteria but still require urgent attention due to the risk of severe consequences for both mother and child.
• Psychotic Depression: Although less common, psychotic symptoms can occur in the context of depressive disorders. Missing this diagnosis can lead to inadequate treatment and increased risk of harm to self or others.

Rare Diagnoses

• Depressive Disorder Due to Another Medical Condition: Certain medical conditions can cause depressive symptoms that do not meet the full criteria for MDD. Identifying the underlying condition is crucial for appropriate management.
• Substance-Induced Depressive Disorder: This diagnosis is considered when depressive symptoms are directly related to the use of a substance. It's essential to differentiate this from independent depressive disorders.
• Premenstrual Dysphoric Disorder: Characterized by depressive symptoms that are specifically linked to the menstrual cycle, this condition requires a detailed history to diagnose accurately.