What causes substernal pressure in patients with Coccidioidomycosis (Coccidioides pneumonia)?

Common Causes of Substernal Pressure in Coccidioidomycosis

Substernal pressure in coccidioidomycosis is most commonly caused by chronic fibrocavitary pneumonia, which requires treatment with oral azole antifungal agents such as fluconazole or itraconazole for at least one year. 1

Pathophysiological Mechanisms

Substernal pressure in coccidioidomycosis can result from several disease processes:

1. Chronic Fibrocavitary Pneumonia

   • Characterized by fibrosis and cavitation in the lungs
   • Causes chronic inflammation and chest discomfort
   • Often presents with sputum production and substernal pressure 1
   • Symptoms typically wax and wane over time

2. Pulmonary Cavities

   • Occurs in approximately 5% of coccidioidomycosis cases 1
   • Cavities can range from small to very large
   • When located near the sternum, can cause substernal pressure
   • May be associated with chronic inflammation of surrounding tissue

3. Complications of Cavitary Disease

   • Fungal Ball (Mycetoma) - Can develop within cavities, causing pressure symptoms 2
   • Bacterial or Fungal Superinfection - Secondary infections within cavities 1
   • Pleural Involvement - When cavities are adjacent to the pleura 1

4. Mediastinal Lymphadenopathy

   • Prominent hilar adenopathy can cause substernal pressure 1
   • More common in severe primary infections

Management Approach

Assessment

1. Determine Severity and Chronicity

   • Evaluate duration of symptoms (acute vs. chronic)
   • Assess for weight loss, night sweats, hemoptysis
   • Check for signs of dissemination

2. Imaging Studies

   • Chest radiography to identify cavities, infiltrates, or adenopathy
   • CT scan for better characterization of lesions
   • Follow-up imaging to monitor progression

Treatment Algorithm

1. For Asymptomatic Cavities:

   • Observation without antifungal therapy is recommended 1
   • Periodic follow-up with chest radiographs

2. For Symptomatic Chronic Cavitary Disease:

   • First-line: Oral azole therapy (fluconazole 400 mg daily or itraconazole 200 mg twice daily) 1
   • Continue treatment for at least 1 year
   • Monitor for symptom improvement and radiographic changes

3. For Severe or Progressive Disease:

   • Consider amphotericin B for patients not responding to azoles 1
   • Reserve for patients with severe illness requiring intensive care

4. For Persistent Symptomatic Cavities:

   • Consider surgical options when:
     • Cavities persist for >2 years
     • Symptoms recur when antifungal treatment is stopped
     • VATS approach is preferred when feasible 1

Special Considerations

Complications Requiring Urgent Attention

1. Cavity Rupture

   • Presents with sudden chest pain and respiratory distress
   • Requires prompt surgical intervention (decortication and resection) 1
   • Continue antifungal therapy post-surgery

2. Hemoptysis

   • May occur with erosion into blood vessels 2
   • Can be life-threatening if severe
   • May require surgical intervention

Monitoring

• Follow patients with symptomatic disease at 1-3 month intervals 1
• Monitor with serologic tests and radiographic examinations
• Assess for resolution of pulmonary infiltrates
• Watch for signs of extrapulmonary dissemination

Pitfalls and Caveats

1. Recurrence Risk

   • Even with prolonged treatment, symptoms recur in approximately 30% of patients after discontinuation 1
   • May require extended or indefinite therapy in some cases

2. Diagnostic Challenges

   • Coccidioidomycosis often mimics bacterial pneumonia 3
   • Consider coccidioidomycosis in patients with pneumonia who have traveled to endemic areas 4

3. Treatment Duration

   • Premature discontinuation of therapy can lead to relapse
   • Insufficient treatment may allow progression to disseminated disease

4. Superinfection

   • Always consider bacterial or other fungal superinfection in patients who do not respond to antifungal therapy 1
   • May require additional antimicrobial treatment

By addressing the underlying cause of substernal pressure in coccidioidomycosis and following appropriate treatment guidelines, most patients can achieve symptom control and prevent serious complications.