Differential Diagnosis for a Sad Person

• Single most likely diagnosis
  • Major Depressive Disorder (MDD): This is the most likely diagnosis for a sad person, as it is characterized by persistent feelings of sadness, loss of interest in activities, and other symptoms that significantly impair daily functioning.
• Other Likely diagnoses
  • Adjustment Disorder with Depressed Mood: This condition involves a maladaptive reaction to a clearly identifiable stressful event or change in a person's life, leading to symptoms of depression.
  • Dysthymia (Persistent Depressive Disorder): A chronic form of depression where the symptoms last for years but are less severe than in MDD.
  • Bipolar Disorder (depressed phase): While mania or hypomania is a key feature of bipolar disorder, during the depressed phase, the primary symptoms can resemble those of MDD.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Suicidal Ideation: Regardless of the underlying diagnosis, assessing for suicidal thoughts or intentions is crucial, as it can be a feature of several psychiatric conditions and requires immediate intervention.
  • Hypothyroidism: Although less common, hypothyroidism can cause symptoms of depression and, if left untreated, can lead to more severe health issues.
  • Substance-Induced Mood Disorder: Certain substances can induce depressive symptoms, and identifying the substance is critical for appropriate management.
• Rare diagnoses
  • Postpartum Depression: While not rare in the postpartum period, it is specific to new mothers and can have severe consequences if not addressed.
  • Seasonal Affective Disorder: A type of depression related to seasonal changes, typically occurring during the winter months.
  • Grief/Bereavement: Complicated grief can present similarly to depression but is a response to loss, requiring a sensitive and supportive approach.
  • Neurodegenerative diseases (e.g., early stages of Alzheimer's disease, Huntington's disease): In rare cases, depressive symptoms can be an early manifestation of a neurodegenerative disorder.