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What is the most likely cause of this symptom?

What is the most likely cause of this symptom?

Dr. Shoaib Ahmad Baig
December 17, 2024

🔍 Question

A 56-year-old man presents to the clinic with a recent onset of headache and shortness of breath. He reports facial puffiness for the past two weeks along with a persistent, dry cough. He denies any shoulder or neck pain and has no known medical history. On examination, there is symmetrical swelling of the face and conjunctival edema. The pupils are equal, round, and reactive to light. Prominent veins are visible on the neck and upper chest. Heart and lung auscultation reveal normal findings, and the patient’s peripheral strength and sensation are intact.

What is the most likely cause of these symptoms?

• A. Airway obstruction

• B. Autoimmune disease

• C. Excessive hormone secretion

• D. Mediastinal mass

• E. Pericardial effusion

• F. Pleural effusion

• G. Superior sulcus tumor

Correct Answer: Mediastinal Mass (D)

⚙️Compression of Superior Vena Cava (SVC) by a Mediastinal Mass (D. Mediastinal Mass)

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🧠 SVC Syndrome

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⚙️

1. Venous Outflow Obstruction in SVC

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↑ Venous pressure in head, neck, and upper trunk

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Symptoms:

• Facial swelling (due to venous stasis)

• Conjunctival edema (↑ venous pressure in ocular region)

• Dilated neck veins (backflow of venous blood)

• Dyspnea & Cough (tracheal compression or venous congestion in lungs)

🧠 SVC Syndrome = Dam Blocking a River

• Obstruction (Mediastinal Mass) = Dam (Compression)

• ↑ Pressure behind the dam = Swelling & congestion in head/neck.

⚖️ Explanation of Other Differentials

Differential	Mechanism
Airway Obstruction	Airway narrowing → Dyspnea, wheezing, stridor No stridor or localized airway symptoms.
Autoimmune Disease	Autoimmune inflammation → Systemic signs (rash, arthralgia) Absence of such symptoms
Excessive Hormone Secretion	Paraneoplastic syndromes (e.g., ACTH, ADH secretion) No evidence of hypercortisolism, hyponatremia, or related endocrine abnormalities.
Pericardial Effusion	Fluid compressing the heart → Cardiac tamponade (↓ cardiac output) No pulsus paradoxus, hypotension, or muffled heart sounds.
Pleural Effusion	Fluid in pleural space → Dyspnea, dullness to percussion Normal lung sounds, no pleural findings.
Superior Sulcus Tumor	Apical lung tumor compressing brachial plexus or nearby structures → Shoulder pain, arm weakness, Horner syndrome No shoulder pain, Horner’s syndrome, or upper limb weakness.

📝 Flashcards

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Stay Hungry, Stay Curious!

Your Brother In This Struggle

Dr. Shoaib Ahmad

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