High frequency of infection of lung cancer patients with the parasite Toxoplasma gondii

Bajnok, J; Tarabulsi, M; Carlin, HV; Bown, K; Southworth, T; Dungwa, J; Singh, D; Lun, Z-R; Smyth, LJC; Hide, G

Abstract

Toxoplasma gondii is an intracellular protozoan parasite that can cause a wide range of clinical conditions, including miscarriage and pneumonia. The global prevalence is 30% in humans but varies locally (e.g. UK is typically 10%). The association between lung cancer and Toxoplasma gondii infection was investigated by direct detection in lung tissue samples. Lung tissue samples were taken from patients undergoing lung resection surgery (n=72) for suspected lung cancer (infection prevalence 100% (95% CI: 93.9% - 100)). All 72 participants were confirmed as having lung cancer following subsequent diagnostic tests. Additionally, bronchial biopsy samples were collected from non-lung cancer healthy control subjects (n=10). Samples were tested for T. gondii using PCR amplification of T. gondii specific gene markers and T. gondii specific immunohistochemistry. All 72 lung cancer patients were infected with T. gondii (prevalence 100% (95% CI: 93.9% - 100%)). Of which, 95.8% (n=69) of patients showed evidence of active parasite stages. Infection prevalence in the controls (10%) was significantly lower (P<0.0001). Clinicians treating lung cancer patients should be aware of the potential presence of the parasite, the potential for induction of symptomatic complications and interference with treatment success.

Keywords: Toxoplasma; lung cancer; PCR; Immunohistochemistry; infectious disease; COPD

Citation

Bajnok, J., Tarabulsi, M., Carlin, H., Bown, K., Southworth, T., Dungwa, J., …Hide, G. (2019). High frequency of infection of lung cancer patients with the parasite Toxoplasma gondii. ERJ Open Research, 5(2), 1-10. https://doi.org/10.1183/23120541.00143-2018

• Journal Article Type: Article
• Acceptance Date: Mar 23, 2019
• Online Publication Date: May 28, 2019
• Publication Date: May 28, 2019
• Deposit Date: May 23, 2019
• Publicly Available Date: May 29, 2019
• Journal: ERJ Open Research
• Publisher: European Respiratory Society
• Volume: 5
• Issue: 2
• Pages: 1-10
• DOI: https://doi.org/10.1183/23120541.00143-2018
• Publisher URL: https://doi.org/10.1183/23120541.00143-2018
• Related Public URLs: https://openres.ersjournals.com/; https://www.salford.ac.uk/environment-life-sciences/our-staff/els-academics/geoff-hide