Pulmonary Aspergilloma: A Post-Tuberculosis Complication with Life-Threatening Consequences

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Pulmonary Aspergilloma: A Post-Tuberculosis Complication with Life-Threatening Consequences

Introduction

Pulmonary aspergilloma, also known as an aspergillus fungus ball, is a saprophytic form of Aspergillus colonization that typically occurs in pre-existing pulmonary cavities, especially in individuals with a history of pulmonary tuberculosis (TB). The clinical presentation can range from asymptomatic to life-threatening hemoptysis. This article delves into a detailed case study and expands on the cause, etiology, pathophysiology, imaging findings, and treatment strategies for pulmonary aspergilloma, along with a discussion of its prognosis and relevance in global healthcare.

Case Presentation

A 48-year-old man presented with mild hemoptysis for one week. He had a known history of treated pulmonary tuberculosis. A chest CT scan revealed a thick-walled cavity in the right upper lobe and a newly appeared intracavitary mass.

Figure 1. Axial chest CT showing a thick-walled cavitary lesion in the right upper lobe with a dependent soft-tissue mass consistent with a fungus ball.

On repeat CT, taken 16 months after the initial scan, thickening of the cavity wall and the presence of a new fungal ball were evident. The radiological findings were consistent with pulmonary aspergilloma. No evidence of recurrent tuberculosis was found. The diagnosis was confirmed with sputum culture and histopathology, which showed characteristic dichotomously branching septate hyphae.

Discussion

1. Cause and Etiology

Pulmonary aspergilloma is caused by the colonization of the Aspergillus species—most commonly Aspergillus fumigatus—within a pre-existing pulmonary cavity. These cavities usually arise from:

  • Healed pulmonary tuberculosis

  • Sarcoidosis

  • Bronchiectasis

  • Bullous emphysema

  • Neoplasms

Spores are inhaled and deposited into the cavity, where the local immune defenses are unable to clear the fungus due to the absence of a vascular supply in the necrotic cavity wall.

2. Pathophysiology

Aspergillus spores germinate in the cavity, forming a mass composed of fungal hyphae, inflammatory cells, fibrin, and cellular debris. The fungus ball remains mobile within the cavity and may erode adjacent blood vessels, particularly bronchial arteries, leading to hemoptysis. In rare cases, erosion into the pulmonary artery may lead to fatal bleeding.

3. Epidemiology

Pulmonary aspergilloma is more prevalent in regions with a high burden of tuberculosis. Globally, the estimated prevalence is about:

  • 1.2 million cases per year are associated with post-TB cavities

  • Up to 22% of patients with cavitary TB may develop an aspergilloma
    It is most commonly seen in middle-aged to older males with a previous history of pulmonary infections or immunocompromised states.

4. Clinical Presentation

Most patients with aspergilloma are asymptomatic; however, the classic symptoms include:

  • Chronic cough

  • Hemoptysis (intermittent to massive)

  • Fatigue

  • Weight loss

  • Fever (rare, unless co-infection occurs)

Massive hemoptysis can be fatal and is the most feared complication. The risk increases with the size and location of the fungus ball.

5. Imaging Features

Figure 2. Repeat CT after 16 months shows progression: thickened wall and dependent intracavitary soft tissue mass within the right upper lobe. The air crescent sign is visible—a hallmark of aspergilloma.

Key radiological features include:

  • Thick-walled cavitary lesions

  • Mobile intracavitary mass

  • The "air crescent sign" (space between mass and cavity wall)

  • Positional mobility of the mass on prone vs. supine scans

CT is superior to X-ray in detecting these features and distinguishing fungal balls from other cavitary contents.

6. Diagnosis

Diagnosis is based on:

  • Imaging findings

  • Sputum culture and microscopy (septate hyphae, dichotomous branching)

  • Serological testing (Aspergillus IgG)

  • Histopathology (in some surgical specimens)

In the present case, microscopy confirmed the presence of septate hyphae, and culture identified Aspergillus fumigatus via MALDI-TOF mass spectrometry.

7. Treatment

Treatment options vary depending on the severity of symptoms and risk of hemorrhage:

a. Observation

  • For asymptomatic, stable aspergillomas

b. Medical therapy

  • Voriconazole is the antifungal of choice

  • Itraconazole as an alternative

  • Amphotericin B (less commonly used due to toxicity)

c. Interventional therapy

  • Bronchial artery embolization (BAE): For controlling hemoptysis

  • Surgical resection (lobectomy): Reserved for massive or persistent hemoptysis and localized disease

In this case, voriconazole was initiated. However, the patient was lost to follow-up and returned 14 months later with massive hemoptysis requiring emergency pulmonary artery embolization.

8. Prognosis

Prognosis depends on:

  • Size and location of the aspergilloma

  • Immune status

  • Timely medical or surgical intervention

Overall mortality is low for asymptomatic cases but significantly higher in those with massive hemoptysis. Recurrent bleeding is a common concern, often requiring multiple interventions.

Quiz

1. Which of the following drugs is appropriate for treating pulmonary aspergilloma?

(1) Azithromycin
(2) Rifampin
(3) Rituximab
(4) Trimethoprim-sulfamethoxazole
(5) Voriconazole

2. What is the hallmark imaging sign of a pulmonary aspergilloma?

(1) Tree-in-bud pattern
(2) Air crescent sign
(3) Crazy paving
(4) Ground-glass opacity
(5) Pleural effusion

3. What is the most serious complication of pulmonary aspergilloma?

(1) Dyspnea
(2) Cavitary expansion
(3) Massive hemoptysis
(4) Bronchiectasis
(5) Pneumothorax

4. Which of the following conditions is most likely to predispose to pulmonary aspergilloma?

(1) Asthma
(2) Silicosis
(3) Pulmonary tuberculosis
(4) Interstitial lung disease
(5) Lung cancer

Answer & Explanation

1. Answer: (5)
Explanation: Voriconazole is the antifungal of choice for invasive and saprophytic forms of aspergillosis. The others are inappropriate for this fungal infection.

2. Answer: (2)
Explanation: The air crescent sign indicates a fungus ball within a cavity surrounded by air, typically seen in aspergilloma.

3. Answer: (3)
Explanation: Erosion into blood vessels by the fungal mass can cause a life-threatening hemorrhage.

4. Answer: (3)
Explanation: Pre-existing cavities from prior TB infections are the most common sites for aspergilloma development.

Conclusion

Pulmonary aspergilloma represents a classic example of opportunistic fungal colonization in a structurally compromised lung. Although often indolent, it poses serious hemorrhagic risks. Early recognition, appropriate imaging, microbiological confirmation, and timely therapeutic intervention—especially in post-tuberculosis patients—are key to improving outcomes.

References

[1] A. Patterson, D. Thompson, and J. Denning, "Aspergilloma: Diagnosis and Management," Clin. Infect. Dis., vol. 62, no. 7, pp. 760–768, Apr. 2016.

[2] D. Kosmidis and D. W. Denning, "The clinical spectrum of pulmonary aspergillosis," Thorax, vol. 70, no. 3, pp. 270–277, Mar. 2015.

[3] G. Cadranel et al., "Fungal infections in patients with preexisting lung diseases," Eur. Respir. J., vol. 47, no. 3, pp. 947–963, Mar. 2016.

[4] R. Smith and S. Nguyen, "Pulmonary Aspergilloma after Tuberculosis," Chest, vol. 145, no. 2, pp. 289–293, Feb. 2014.

[5] B. Kousha, R. Tadi, and A. Soubani, "Pulmonary aspergillosis: a clinical review," Eur. Respir. Rev.., vol. 20, no. 121, pp. 156–174, Sep. 2011.

[6] J. Hope et al., "The diagnosis and management of aspergillosis," J. Infect., vol. 72, no. 2, pp. S15–S20, Feb. 2016.

[7] World Health Organization, “Tuberculosis and pulmonary fungal co-infections,” WHO Fungal Priority Pathogens List, 2023.

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