Cytomegalovirus (CMV) may have an impact on disease progression in cystic fibrosis (CF) leading to earlier lung transplant and increased mortality.

A Canadian study, published in the European Respiratory Journal, found that CMV seropositive patients with CF who received a lung transplant or died on a wait-list were about eight years younger than seronegative patients who were also referred for transplant.

The retrospective study comprised 56 patients who were referred for lung transplant at the Calgary Adult Cystic Fibrosis Clinic. Just over half (54.6%) tested positive for CMV.

The study found the composite primary outcome of age at death or bilateral lung transplantation was significantly different between patients seropositive for CMV and those who were not (27.17 v 35.11 years; p<0.001).

Assessed separately, CMV seropositivity was associated with a lower mean age of death (difference 9.35 years, p=0.03) or transplant (difference 7.36 years; p=0.003).

While the findings were limited by relatively small numbers of patients from a single centre, the researchers said it appeared that CMV infection may accelerate disease progression.

One of the lead researchers Associate Professor Michael Parkins, from the University of Calgary, said CMV was normally dormant in people but could become reactivated after co-infection with bacteria.

“We already know that the cytomegalovirus can harm the health of cystic fibrosis patients who have had a lung transplant, as it can increase the risk of organ rejection, but we know very little about how this virus affects pre-transplant cystic fibrosis patients.”

“We know that cystic fibrosis patients are more likely to develop lung infections, so it’s possible that repeated cycles of activation of the virus exaggerates the damage to patients’ lungs, contributing to faster disease progression.”

The researchers said, however, that more evidence was required from larger national and international transplant registries.

“If this association is confirmed in larger multi-centre studies, strategies exploring the use of pre-emptive and prophylactic anti-viral treatments, including acyclovir (while not having significant CMV activity can reduce reactivation potential) or valganciclvoir, in specific populations may be in order.”