What type of esophageal diverticulum is most likely associated with mediastinal granulomas?

Esophageal Traction Diverticulum is Associated with Mediastinal Granulomas

The correct answer is (c) esophageal traction diverticulum, which develops as a direct mechanical consequence of granulomatous mediastinal inflammation pulling on the esophageal wall.

Pathophysiologic Mechanism

Traction diverticula form when mediastinal granulomas—typically from histoplasmosis or tuberculosis—cause desmoplastic reactions in paraesophageal tissue that create full-thickness traction on the esophageal wall, producing a conical, broad-mouthed true diverticulum 1. This differs fundamentally from pulsion diverticula, which lack a muscular coat and result from increased intraluminal pressure rather than external traction 1.

Location and Characteristics

• Traction diverticula occur in the middle third of the thoracic esophagus in a peribronchial location 1
• They often project to the right side because subcarinal lymph nodes are closely associated with the right anterior esophageal wall 1
• These are true diverticula containing all layers of the esophageal wall, unlike false pulsion diverticula 1

Underlying Etiology

Mediastinal granulomas result from:

• Histoplasmosis (most common in endemic areas) 2, 3, 4
• Tuberculosis 1, 5
• Sarcoidosis (rare) 5

The granulomatous inflammation causes abnormal enlargement of mediastinal lymph nodes, which can compress the esophagus and create traction forces 3, 6.

Clinical Presentation

Traction diverticula typically present with:

• Dysphagia 1
• Postural regurgitation 1
• Retrosternal pain and heartburn 1
• Pulmonary symptoms ranging from nocturnal cough to aspiration 1
• Upper GI bleeding (rare but documented) 1, 4

Why Other Options Are Incorrect

• (a) Epiphrenic diverticulum: Located in the distal esophagus near the diaphragm, associated with motility disorders rather than mediastinal inflammation 1
• (b) Zenker's diverticulum: Located at the cricopharyngeus muscle in the cervical esophagus, caused by increased intraluminal pressure (pulsion mechanism), not mediastinal pathology 1
• (d) Achalasia: A primary esophageal motility disorder unrelated to mediastinal granulomas, though mediastinal fibrosis can cause esophageal compression 3

Diagnostic Approach

• Chest X-ray may show mediastinal abnormalities 1
• Barium esophagogram demonstrates the diverticulum and its relationship to mediastinal structures 1
• CT chest can identify mediastinal granulomas and fibrosis 3, 6
• Esophageal manometry evaluates for associated motility disorders 1

Management Considerations

• Most traction diverticula are asymptomatic and require no treatment 3, 6
• Treat underlying granulomatous disease when active infection is present 2, 3
• Surgical resection with esophageal myotomy is reserved for symptomatic patients with complications 1, 3
• Antifungal therapy (itraconazole 200 mg once or twice daily for 6-12 weeks) may be indicated if clinical findings suggest active mediastinal granuloma rather than chronic fibrosis 2

Critical Pitfall

Do not confuse mediastinal granuloma with chronic fibrosing mediastinitis—the former is typically benign and self-resolving, while the latter involves extensive fibrosis causing serious compression of mediastinal structures and carries a worse prognosis 3, 6. If clinical differentiation is unclear, a trial of itraconazole may be warranted 2.