A 33-year-old woman is brought to the physician by her husband because of persistent sadness for the past 2 months. During this period, she also has had difficulty sleeping and an increased appetite. She had similar episodes that occurred 2 years ago and 9 months ago that each lasted for 4 months. Between these episodes, she reported feeling very energetic and rested after 3 hours of sleep. She often went for long periods of time without eating. She works as a stock market trader and received a promotion 5 months ago. She regularly attends yoga classes on the weekends with her friends. On mental status examination, she has a blunted affect. She denies suicidal thoughts and illicit drug use. Which of the following is the most likely diagnosis?

Major depressive disorder with seasonal pattern

Major depressive disorder with atypical features

A 38-year-old woman comes to the physician for a follow-up visit. She has a 2-year history of depressed mood and fatigue accompanied by early morning awakening. One week ago, she started feeling a decrease in her need for sleep and now feels rested after about 5 hours of sleep per night. She had two similar episodes that occurred 6 months ago and a year ago, respectively. She reports increased energy and libido. She has a 4-kg (8.8-lb) weight loss over the past month. She does not feel the need to eat and says she derives her energy ""from the universe"". She enjoys her work as a librarian. She started taking fluoxetine 3 months ago. On mental exam, she is alert and oriented to time and place; she is irritable. She does not have auditory or visual hallucinations. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?

Medication-induced bipolar disorder

A 38-year-old man comes to the physician because of persistent sadness and difficulty concentrating for the past 6 weeks. During this period, he has also had difficulty sleeping. He adds that he has been “feeling down” most of the time since his girlfriend broke up with him 4 years ago. Since then, he has only had a few periods of time when he did not feel that way, but none of these lasted for more than a month. He reports having no problems with appetite, weight, or energy. He does not use illicit drugs or alcohol. Mental status examination shows a depressed mood and constricted affect. Which of the following is the most likely diagnosis?

Adjustment disorder with depressed mood

A 32-year-old woman is brought to the physician by her husband, who is concerned about her ability to care for herself. Three weeks ago, she quit her marketing job to start a clothing company. Since then, she has not slept more than 4 hours per night because she has been working on her business plans. She used a significant portion of their savings to fund business trips to Switzerland in order to buy “only the best quality fabrics in the world.” She has not showered and has eaten little during the past 3 days. She has had 2 similar episodes a few years back that required hospitalization and treatment in a psychiatry unit. She has also suffered from periods of depression. She is currently not taking any medications. She appears unkempt and agitated, pacing up and down the room. She speaks very fast without interruption about her business ideas. She has no suicidal ideation or ideas of self-harm. Toxicology screening is negative. Which of the following is the most appropriate pharmacotherapy for the management of this patient?

Clonazepam therapy for one year

Sertraline therapy for one year

A 24-year-old woman is brought to the emergency department by her roommate because of bizarre behavior and incoherent talkativeness for the past week. Her roommate reports that the patient has been rearranging the furniture in her room at night and has ordered a variety of expensive clothes online. The patient says she feels “better than ever” and has a lot of energy. She had absence seizures as a child and remembers that valproate had to be discontinued because it damaged her liver. She has been otherwise healthy and is not taking any medication. She is sexually active with her boyfriend. She does not smoke, drink alcohol, or use illicit drugs. Physical and neurologic examinations show no abnormalities. Her pulse is 78/min, respirations are 13/min, and blood pressure is 122/60 mm Hg. Mental status examination shows pressured and disorganized speech, flight of ideas, lack of insight, and affective lability. Which of the following is the best initial step before deciding on a therapy for this patient's condition?

Obtain TSH, β-hCG, and serum creatinine concentration

Obtain CBC, liver function studies, and beta-HCG

Obtain BMI, HbA1c, lipid levels, and prolactin levels

Perform urine drug testing and begin cognitive behavior therapy

Assess for suicidal ideation and obtain echocardiography

A 24-year-old woman presents to her primary care physician for a wellness exam. She currently has no acute concerns but has been feeling hopeless, has a poor appetite, difficulty with concentration, and trouble with sleep. She says that she has poor self-esteem and that her symptoms have been occurring for the past 3 years. She has had moments where she felt better, but it lasted a few weeks out of the year. She currently lives alone and does not pursue romantic relationships because she feels she is not attractive. She has a past medical history of asthma. Her mother is alive and healthy. Her father committed suicide and suffered from major depressive disorder. On physical exam, the patient has a gloomy demeanor and appears restless and anxious. Which of the following is the most likely diagnosis?

Disruptive mood dysregulation disorder

A 26-year-old female college student is brought back into the university clinic for acting uncharacteristically. The patient presented to the same clinic 6 weeks ago with complaints of depressed mood, insomnia, and weightloss. She had been feeling guilty for wasting her parent’s money by doing so poorly at the university. She felt drained for at least 2 weeks before presenting to the clinic for the first time. She was placed on an antidepressant and was improving but now presents with elevated mood. She is more talkative with a flight of ideas and is easily distractible. Which of the following statements is most likely true regarding this patient’s condition?

Her diagnosis of unipolar depression is incorrect.

The patient may have psychotic features.

The patient may have a history of mania.

Antidepressants are inappropriate.

Her new symptoms need to last at least 7 days.

Cyclothymic disorder for USMLE Step 2 CK: High-Yield Psychiatry Lessons

Cyclothymia - The Moody Blues

Mood fluctuations in unipolar, bipolar, and cyclothymia

A chronic, fluctuating mood disturbance considered a milder form of bipolar disorder.
Clinical Criteria (DSM-5):
- Numerous periods with hypomanic and depressive symptoms for at least 2 years in adults (1 year in children/adolescents).
- Symptoms do not meet the full criteria for a hypomanic or major depressive episode.
- Symptomatic periods are present for at least half the time.
- The patient is not symptom-free for more than 2 months at a time.

⭐ High-Yield: Up to 15-50% of individuals with cyclothymia will eventually be diagnosed with Bipolar I or Bipolar II disorder.

Management:
- Psychotherapy (CBT, DBT) is the cornerstone of treatment.
- Mood stabilizers (e.g., lithium, valproate) may be considered if there is significant functional impairment.

Diagnosis - The 2-Year Rule

Core Duration (The "2s"): For ≥ 2 years (adults) or ≥ 1 year (children/adolescents), patient experiences numerous periods of mood disturbance.
Symptom Persistence:
- Hypomanic & depressive symptoms are present for at least half the time during this period.
- Any symptom-free intervals last no longer than 2 consecutive months.
Sub-threshold Nature: The symptoms cause clinically significant distress or impairment but have never met the full criteria for a major depressive, manic, or hypomanic episode.

⭐ High-Yield: A significant portion (15-50%) of patients with cyclothymia will eventually progress to a full Bipolar I or Bipolar II disorder diagnosis. Early recognition is key.

Mood chart: Bipolar vs. Cyclothymic disorder features

Differential Dx - The Lineup

Bipolar I & II: Defined by at least one full manic (BPI) or hypomanic/major depressive (BPII) episode. Cyclothymia's highs and lows are less severe.
Borderline Personality Disorder (BPD): Mood shifts are typically more rapid and reactive to interpersonal stressors, part of a pervasive pattern of instability.

⭐ In cyclothymia, symptoms are chronic but sub-threshold. They must be present for at least 2 years (1 year in children/adolescents), with symptoms present for at least half the time and never absent for more than 2 months at a time.

Management - Taming the Swings

Psychotherapy is the cornerstone of treatment, focusing on education and coping skills.
- Cognitive Behavioral Therapy (CBT) helps identify and modify thought patterns.
- Psychoeducation and establishing regular routines (sleep, diet) are crucial.
Pharmacotherapy is considered if functional impairment is severe or psychotherapy is insufficient.

⭐ Antidepressant monotherapy is generally avoided due to the risk of inducing hypomania or rapid cycling. If necessary, they should be used cautiously with a primary mood stabilizer.

High‑Yield Points - ⚡ Biggest Takeaways

A chronic, fluctuating mood disturbance for at least 2 years (1 year in children/adolescents).

Numerous periods with hypomanic symptoms and periods with depressive symptoms that do not meet full criteria for an episode.

The patient is not symptom-free for more than 2 months at a time.

Considered a milder form of bipolar disorder; high risk of progressing to Bipolar I or II.

Must cause clinically significant distress or impairment.

Continue reading on Oncourse

CONTINUE READING — FREE

or get the app

App Store|Google Play