Late stage sepsis, which is the leading cause of death in hospitals, could be linked to prolonged episodes of infection with reactivation of otherwise-dormant viruses in the body, a new study has found. The research, published June 11 in the open access journal PLOS ONE by Richard S. Hotchkiss and colleagues from the Washington University School of Medicine in St. Louis, suggests that drugs that "rev up" the immune system could be incorporated into the treatment of late-stage sepsis.
In healthy people, latent viruses are kept in check by the immune system. Sepsis develops when the body mounts a massive immune response to infection, triggering excessive inflammation that can lead quickly to organ failure. This study provides strong evidence that when sepsis lingers for more than a few days, as is common, viruses re-emerge and enter the bloodstream, signaling that the immune system has become suppressed, and leaving patients unable to fight off secondary infections.
In the current study, the authors used polymerase chain reaction (PCR) testing to detect a range of viruses in blood and urine samples from critically ill patients with sepsis. As a comparison, they performed the same test on critically ill patients in the hospital who did not have sepsis and healthy patients who were having outpatient surgery.
Researchers noted that 43 percent of sepsis patients who were tested for some viruses had two or more viruses detected in their blood or urine during their hospital stays, and in a subgroup of patients tested for all viruses, 54 percent were positive for two or more. The authors also found that septic patients with higher levels of viruses in their blood were more likely to have severe illnesses, secondary fungal and bacterial infections, and longer stays in the intensive care unit.
"We stumbled onto more viruses than we expected, and we don't know yet whether some of these viruses are causing problems in their own right," co-author Gregory Storch, MD, said. "We think this paper will stimulate others to carry out further investigations of the role of latent viruses in sepsis."
The authors hope that, in addition to using powerful antibiotics to fight off infections in patients with sepsis, immunotherapy drugs that boost the immune system may be an effective therapy.