Study: Cytomegalovirus May Play a Role in Cystic Fibrosis Progression

Patients with cystic fibrosis (CF) who have cytomegalovirus (CMV), a common type of herpes virus, may have faster disease progression than those who do not have the virus, according to a new study published in European Respiratory Journal.

CMV is often contracted during late adolescence and early adulthood and typically does not cause symptoms in otherwise healthy individuals. However, the virus has been previously linked to the development of chronic conditions such as Alzheimer disease, heart disease, and cancers. CMV has also been shown to increase the risk of organ rejection in patients with CF who have had a lung transplant, but no studies have examined how the virus affects pre-transplant patients with CF.

For the study, the researchers analyzed 56 patients with CF who were referred for lung transplant at Calgary Adult Cystic Fibrosis Clinic. They aimed to determine whether CMV serostatus was associated with patient pre-transplant outcomes. Of the patients in the study, 54.6% tested positive for CMV. The researchers also looked at patients’ sex, body mass index, education, and presence of other infections and genetic traits.

Overall, the analysis revealed that infection with CMV was the most important contributor to disease progression for these patients. In CF, signs of faster disease progression include earlier times to lung transplant referral and reaching the final stages of the disease. According to the study, patients with CMV were referred for lung transplants 8 years earlier on average than patients without CMV. In addition, patients with the virus also died 10 years earlier on average, compared with those without the virus.

The researchers suggested that since patients with CF are more likely to develop lung infections, repeated cycles of activation of the virus may exacerbate damage to their lungs and contribute to faster disease progression.

“The association we found does not necessarily mean that cytomegalovirus directly causes more rapid disease progression—further studies are needed before such a bold statement could be made,” lead study author Michael Parkins, MD, associate professor of medicine, microbiology, and infectious diseases at the University of Calgary, Canada, said in a press release. “However, our findings provide the first indication that this virus may have an impact on progression of cystic fibrosis, potentially leading to earlier transplant referral and even death.”

Dr Parkins indicated that providers can focus on several interventions to manage CMV in patients with CF, including treatment that may slow the spread of the virus or treatment given only during times of reactivation.

Despite these findings, the researchers noted that the study is limited by the small number of patients included who all came from 1 clinic and by the lack of information about the direct cause of death or transplantation among patients. Further studies are warranted to confirm the role of CMV in CF progression, they concluded.

References

Parkins M, Ramos KJ, Goss CH, et al. Cytomegalovirus — an unrecognized potential contributor to cystic fibrosis disease progression? European Respiratory Journal. 2019. Doi: 10.1183/13993003.01727-2018

Common virus linked to faster disease progression in cystic fibrosis [news release]. European Respiratory Society. https://www.ersnet.org/the-society/news/common-virus-linked-to-faster-disease-progression-in-cystic-fibrosis. Accessed April 8, 2019.