Presenting Complaints

The patient, a 43-year-old male from Malaysia, presents with a chief complaint of mood swings over the past 3 months.

History of Presenting Complaint

The patient reports that he has been experiencing significant changes in his mood, ranging from periods of irritability and restlessness to episodes of lethargy and low mood. He states that these mood swings occur seemingly without any clear triggers and can last for several days at a time. He also notes that his energy levels have been fluctuating, with some days where he feels fatigued and has difficulty concentrating, while on other days he feels unusually energetic.

Significant Positives & Negatives For Differentials

Hypothyroidism

Positives:

• Family history of hypothyroidism
• Symptoms of fatigue, changes in appetite, constipation
• Fluctuating energy levels

Negatives:

• Lack of other typical hypothyroid symptoms (cold intolerance, dry skin, hair loss)
• No reported changes in temperature regulation

Hyperthyroidism

Positives:

• Mood swings and irritability can be associated with hyperthyroidism
• Fluctuating energy levels

Negatives:

• Lack of other typical hyperthyroid symptoms (weight loss, tremors, palpitations)
• No reported changes in temperature regulation

Bipolar Disorder

Positives:

• Mood swings between irritability/restlessness and lethargy/low mood
• No clear triggers for mood changes

Negatives:

• Lack of clear manic episodes with increased goal-directed activity, decreased need for sleep
• No reported changes in speech, thought patterns, or psychosis

Major Depressive Disorder

Positives:

• Periods of low mood and lethargy

Negatives:

• Lack of persistent low mood, anhedonia, and other typical depressive symptoms
• Presence of irritability and restlessness, which are less common in unipolar depression

Chronic Stress/Burnout

Positives:

• Demanding work schedule with long hours and frequent travel
• Fluctuating energy levels and mood changes

Negatives:

• Lack of other typical burnout symptoms like emotional exhaustion, depersonalization
• Mood changes seem more severe and persistent than expected with burnout

Past Medical History

The patient has a history of hypertension, which has been well-controlled with medication. He also had a bout of pneumonia 2 years ago that required hospitalization. Otherwise, his medical history is unremarkable.

Drug/Medication History

The patient is currently taking hydrochlorothiazide for his hypertension. He denies any other regular medication use.

Social History

The patient is married and works as an accountant. He reports that his work schedule has been quite demanding over the past few months, with long hours and frequent travel. He also enjoys playing soccer on the weekends with his friends.

Family History

The patient's mother has a history of hypothyroidism, for which she takes levothyroxine. There is no other significant family history of endocrine disorders or mood disorders.

Systems Review

• General: The patient reports fluctuating energy levels and changes in appetite, with some days of increased hunger and other days of decreased appetite.
• Cardiovascular: Denies chest pain, palpitations, or shortness of breath.
• Respiratory: Denies any respiratory symptoms.
• Gastrointestinal: Occasional constipation, but no significant changes in bowel habits.
• Genitourinary: Denies any urinary symptoms.
• Neurological: Denies any headaches, dizziness, or changes in vision.
• Psychiatric: As mentioned, the patient reports significant mood swings, ranging from irritability to lethargy.
• Endocrine: Denies any changes in hair, skin, or temperature regulation.

Ideas, Concerns & Expectations

The patient is concerned that his mood swings may be related to an underlying medical condition, as he has not experienced anything like this before. He is hoping the doctor can help identify the cause and provide appropriate treatment.

Case Presentation

Based on the patient's presentation, the most likely diagnosis is hypothyroidism. The patient's mood swings, fluctuating energy levels, changes in appetite, and family history of thyroid disorder are all consistent with an underactive thyroid. While other differential diagnoses like hyperthyroidism, bipolar disorder, and major depressive disorder should be considered, the overall clinical picture points more strongly towards hypothyroidism as the primary driver of the patient's symptoms. To confirm the diagnosis, the next steps would be to order thyroid function tests (TSH, free T4) and potentially other laboratory tests to rule out other underlying conditions. A comprehensive physical exam, including an assessment of the thyroid gland, would also be important. Depending on the results, the appropriate treatment plan, which may include medication or lifestyle modifications, can be determined.