A new research study reports on the correlation between infection with Coxiella burnetii, the bacterium that causes Q fever, and an increased risk of lymphoma development. The study, entitled “B-cell non-Hodgkin lymphoma linked to Coxiella burnetii“, was published online in Blood, the Journal of the American Society of Hematology (ASH).
Previously, lymphoma was believed to be a risk factor for Coxiella burnetii infection, since patients diagnosed with this type of cancer also suffered from Q fever. However, researchers questioned this causality hypothesis after identifying one patient that presented a lymphoma tumor containing in its microenvironment Coxiella burnetii, close to the location of the previous infection. This discovery prompted researchers to investigate the reverse theory, that infection with the bacterium may favor lymphoma development.
Researchers screened 1,468 patients, from the French National Referral Center for Q fever database, in the time period between 2004 and 2014. Sample tissues from these patients were analyzed with imaging techniques to identify patients who developed lymphoma after Coxiella burnetii infection.
Seven patients presented mature B-cell lymphoma, specifically 6 with diffuse large B-cell lymphoma and 1 folicullar lymphoma. The risk of developing these conditions for Q fever patients was determined and compared to France’s general population, 25.4% and 6.7%, respectively. Furthermore, researchers concluded that Q fever patients with persistent and localized infections were in greater risk of developing lymphoma when compared to other Q fever patients. Overproduction of IL-10 was also observed in Q fever patients developing lymphoma, suggesting that suppression of the immune system may be involved in the onset of this malignancy.
This study sheds light on a new possible promoter of human B-cell non-Hodgkin lymphoma. senior study author Dr. Didier Raoult, MD, of Aix-Marseille University in Marseille, France, highlighted the importance of these results, “As we continue to learn more about the association between C. burnetii and lymphoma, these results should encourage clinicians to survey high-risk patients as early as possible for potential cancer. Ultimately, this early diagnosis and treatment would improve outcomes for Q fever patients who subsequently develop lymphoma, particularly those with B-cell non-Hodgkin lymphoma.”