A 43-year-old man comes to the emergency room complaining of chest discomfort. He describes the feeling as "tightness," and also reports weakness and palpitations for the past hour. He denies shortness of breath, diaphoresis, or lightheadedness. He has no significant past medical history, and does not smoke, drink, or use illicit drugs. His father had a myocardial infarction at age 72. He is afebrile, heart rate is 125 bpm, and his blood pressure is 120/76. He is alert and oriented to person, place, and time. His electrocardiogram is shown below. Which of the following tests should be ordered in the initial work-up of this patient's condition?

Thyroid stimulating hormone level (TSH)

A 43-year-old male with a history of thyroid cancer status post total thyroidectomy presents to his primary care physician after repeated bouts of headaches. His headaches are preceded by periods of anxiety, palpitations, and sweating. The patient says he is unable to pinpoint any precipitating factors and instead says the events occur without warning. Of note, the patient's father and uncle also have a history of thyroid cancer. On exam his vitals are: T 36.8 HR 87, BP 135/93, RR 14, and O2 Sat 100% on room air. The patient's TSH is within normal limits, and he reports taking his levothyroxine as prescribed. What is the next best step in diagnosing this patient's chief complaint?

Plasma fractionated metanephrines

Abdominal CT scan with and without IV contrast

High dose dexamethasone suppression test

Every time your neighbor in the adjacent apartment flushes the toilet, the water in your shower becomes very hot, causing you to jump out of the way of the water stream. After this has occurred for several months, you note that you reflexively jump back from the water directly after the sound of the flushing toilet but before the water temperature changes. Which of the following situations is the most similar to the conditioning process detailed above?

White coat syndrome (patient anxiety evoked at the sight of a white lab coat)

You consistently check the slots of pay telephones as you have previously found change left there

A young child elects to not throw a temper tantrum to avoid being grounded by his parents

A mouse repeatedly presses a red button to avoid receiving an electric shock

You now sleep through the noise of the train running past your apartment that kept you up 1 year ago

Anxiety in medical conditions for USMLE Step 3: High-Yield Psychiatry Lessons

Anxiety in Medical Conditions - Medically-Induced Jitters

Key Principle: Always rule out underlying medical or substance-related causes before diagnosing a primary anxiety disorder. The temporal link is crucial-symptoms manifest after the onset of the condition or substance use.
Common Medical Culprits:
- Endocrine: Hyperthyroidism, pheochromocytoma, hypoglycemia.
- Cardiopulmonary: Myocardial infarction, pulmonary embolism, SVT.
- Neurologic: Seizure disorders, vestibular dysfunction.
Substance/Medication-Induced:
- Intoxication: Caffeine, stimulants (cocaine, amphetamines).
- Withdrawal: Alcohol, benzodiazepines, opioids.
- Medications: Corticosteroids, albuterol, theophylline.

⭐ A patient presenting with paroxysmal spells of anxiety, palpitations, headache, and sweating should be evaluated for pheochromocytoma.

Pheochromocytoma on Adrenal Gland

Common Medical Causes - The Body's False Alarms

Anxiety symptoms can be mimicked by various medical conditions, crucial to rule out in diagnosis.

System	Condition	Key Clues
Endocrine	Hyperthyroidism	Heat intolerance, weight loss, tremor, tachycardia
	Pheochromocytoma	📌 PHEO: Palpitations, Headache, Episodic sweating
	Hypoglycemia	Tremor, diaphoresis, confusion, often in diabetics
Cardio	MI, PE, Arrhythmia	Chest pain, sudden dyspnea, palpitations
Neuro	Seizures (esp. partial)	Aura, automatisms, post-ictal confusion
Respiratory	COPD, Asthma	Dyspnea, wheezing, history of lung disease

Diagnostic Workup - Playing Medical Detective

Initial screening is crucial to differentiate anxiety from underlying medical conditions. The goal is to rule out organic causes before diagnosing a primary psychiatric disorder.

Core Labs: TSH/T4, CBC, CMP, Urine toxicology screen.
Cardiac: ECG to rule out arrhythmias or ischemia.
Pulmonary: Consider ABG/D-dimer if Pulmonary Embolism (PE) is suspected (sudden onset dyspnea).

⭐ Always consider pheochromocytoma in patients with episodic anxiety, headaches, palpitations, and hypertension. A 24-hour urine metanephrine and catecholamine measurement is a key diagnostic step.

Management - Calming the Storm

Primary Directive: The first step is always to treat the underlying medical condition causing the anxiety.
Symptomatic Relief:
- - Long-term: SSRIs or SNRIs are the first-line agents for sustained management.
- - Short-term Bridge: Benzodiazepines can provide rapid relief but should be used cautiously for brief periods.
- - Somatic Symptoms: Beta-blockers (e.g., propranolol) are effective for controlling palpitations and tremors.
Psychotherapy: Cognitive Behavioral Therapy (CBT) is crucial for addressing maladaptive thought patterns.

⭐ When anxiety is due to pheochromocytoma, never give beta-blockers alone. Always initiate alpha-blockade first to prevent unopposed alpha-agonism and hypertensive crisis.

Always rule out a medical cause for new-onset anxiety, especially in patients with no prior psychiatric history.

Key mimics include hyperthyroidism, pheochromocytoma, hypoglycemia, and cardiopulmonary conditions like MI or PE.

Consider substance/medication-induced anxiety (e.g., caffeine, stimulants, corticosteroids, withdrawal).

A thorough physical exam and initial labs (TSH, glucose, EKG, urine toxicology) are crucial.

Treatment should primarily target the underlying medical condition first.

Continue reading on Oncourse

CONTINUE READING — FREE

or get the app

App Store|Google Play