The Battle of the "New Lung" and the "Old Lung": After a Single-Lung Transplant, Beware the "Fungal Bomb" Lurking in the Native Lung

Introduction: A New Chapter of Life and a Latent Crisis

For patients with end-stage lung disease, a lung transplant is a hope for a new life. However, when donor lungs are scarce, doctors sometimes opt to transplant only one lung, a procedure known as a "single-lung transplant." As a result, the patient's body contains both a healthy "new lung" and a diseased "native lung." A recent study published in the Journal of Thoracic Disease has revealed a significant risk in this situation: a fungal mass called an "aspergilloma" can quietly grow in the native lung, like a lurking "bomb" that could trigger life-threatening massive hemoptysis at any moment. However, the study also brings good news: surgery may no longer be the only option for dealing with this "bomb."

Research Background: What is an Aspergilloma?

Aspergillus is a fungus that is ubiquitous in the environment. We may inhale its spores every day, but for people with a healthy immune system, it usually doesn't cause any problems. However, for patients with pre-existing cavities or lesions in their lungs, the situation is different. Aspergillus spores can "settle down" in these lung cavities, multiply continuously, and mix with mucus, cell debris, and other materials, eventually forming a ball-shaped fungal mass—this is a pulmonary aspergilloma. This "fungal ball" usually does not invade the lung tissue, but it can erode the blood vessels in the cavity walls, leading to recurrent hemoptysis, which can be fatal in severe cases. For patients who have undergone a single-lung transplant, they need to take immunosuppressants for life to prevent rejection of the new lung, which leads to a weakened immune system. On the other hand, the native lung they retain often has structural lesions such as fibrosis and cavities, creating a "perfect" breeding ground for the formation of aspergillomas. Therefore, they are a high-risk group for this complication.

Key Findings: Conservative Treatment May "Defuse the Bomb"

A research team from the Rabin Medical Center in Israel reviewed the medical records of 465 patients who underwent single-lung transplantation at the center from 1997 to 2023. They found 5 cases of aspergilloma in the native lung. The primary disease in all these patients was interstitial lung disease (ILD).

The study results showed that:

1. One patient underwent surgery: This patient, due to recurrent hemoptysis, underwent a native lung resection after antifungal drug therapy and vascular embolization for hemostasis were ineffective. The surgery was very successful, and the patient had no recurrence of hemoptysis for 8 years after the surgery, with a good quality of life.
2. Four patients received conservative treatment: The other four patients only received conservative treatment such as oral antifungal drugs. Encouragingly, three of them remained stable during long-term follow-up (median follow-up of 62 months) and are still alive today.
3. One patient unfortunately passed away: One patient who received conservative treatment died within 6 months of diagnosis, and the cause of death may have been related to the aspergillus infection.

The most important finding of this study is that even in the high-risk group of immunosuppressed single-lung transplant patients, for non-invasive aspergilloma in the native lung, simple antifungal drug therapy can achieve long-term survival, challenging the traditional concept of "operate as soon as it is found."

Brief Description of Research Methods

This was a single-center, retrospective case series study. The researchers systematically reviewed medical records to identify patients who were diagnosed with aspergilloma in the native lung after undergoing a single-lung transplant within a specific time frame. They collected detailed information on these patients' demographic characteristics, primary disease, post-transplant medications, the diagnosis and treatment of the aspergilloma, and the final clinical outcomes, and then summarized and analyzed the data.

Limitations of the Study

The authors acknowledged that this study has some limitations. First, the number of cases is very small, only 5, which limits the generalizability of the study's conclusions. Second, all cases were from the same medical center, so there may be regional or clinical practice biases. Therefore, the results of this study are an important reminder and a new line of thought, but larger, multi-center studies are needed for further confirmation.

Application Prospects and Implications

This study provides valuable insights for clinicians. It emphasizes the importance of long-term imaging surveillance for single-lung transplant patients to detect potential lesions in the native lung early. More importantly, it proposes a more individualized and flexible treatment strategy:

• For asymptomatic or mildly symptomatic patients with a stable condition, conservative treatment with antifungal drugs can be considered first, with close observation, to avoid high-risk surgery.
• For patients with severe hemoptysis, ineffective drug therapy, or continued disease progression, after careful evaluation, surgical resection of the native lung is still an effective and potentially curative option.

In short, treatment decisions should be "tailor-made" to the patient's specific situation, rather than a "one-size-fits-all" approach.

Summary

A single-lung transplant brings new life to many lung disease patients, but the retained native lung can also be a source of complications. This study, through a small number of cases, systematically presents for the first time the experience of diagnosing and treating aspergilloma in the native lung in this special patient population. It tells us that although the risk exists, by increasing vigilance, early detection, and adopting a more individualized treatment strategy—whether it is conservative drug therapy or decisive surgical "bomb disposal"—it is possible to help these patients live safely and for a long time. This study points to a new direction for future clinical practice and related research.

References

1. Tsviban, L., Kramer, M. R., Fridel, L., Shostak, Y., Shitenberg, D., Rosengarten, D., Heching, M., Pesachovich, Y., Barac, Y. D., & Shtraichman, O. (2025). Native lung aspergilloma after single lung transplantation—a case series. Journal of Thoracic Disease.