Pediatric vaccine may offer hemodialysis patients better protection against infections

People undergoing treatment for kidney failure may be able to avoid further complications with doses of vaccines intended for children, suggests the findings of a project being conducted by Lakehead University and researchers at the Northern Ontario School of Medicine.

The five-year study involving patients with severe chronic kidney disease found that the risk of infections was decreased if they received vaccinations normally prescribed for infants.

“We see that a pediatric pneumococcal vaccine works nicely in these people,” says Dr. Marina Ulanova, the principal investigator. “It will be the best way to prevent infection, to use a pediatric vaccine rather than the one that is given to them routinely.”

Dr. William McCready says the purpose of these trials was to understand how best to protect patients with severe kidney disease from developing other serious health issues.

“Patients with kidney failure are more susceptible to infection because their immune systems are impaired by their kidney failure,” says McCready, who has worked as a nephrologist and internist across the Northwest for more than 30 years.

A Lakehead professor and researcher with NOSM, Ulanova’s background is in immunology and pediatrics. She is leading several projects related to infection and disease, particularly in Indigenous populations. Chronic kidney disease is a significant issue in Northern Ontario, which already suffers from high rates of diabetes.

“Chronic kidney disease is a huge issue in northern communities,” she says. “We know their immune system is weakened because of diabetes and kidney disease, and they need better protection against infection.”

The trials began in 2015 and include a mixed group of patients undergoing regular hemodialysis treatment at Thunder Bay Regional Health Sciences Centre. As a result of their compromised immune system, these patients are more likely to develop other problems such as pneumonia and blood stream infections, which can be fatal.

A total of 132 people were enrolled in the program. All received the second-generation pneumococcal vaccine, Prevnar13, and were followed for one year. One group was already immunized with the adult Pneumovax23 vaccine; the other was not. Assessment included immunological response, vaccine safety and longevity of protection.

“Pneumovax23 has some weaknesses,” Ulanova says. “It’s not very strong in inducing immune response. For this reason it was suggested to use the pediatric vaccine for immunization of adult people with weakened immune system. Indeed, we found Prevnar13 worked well in both groups and, moreover, people who have not been previously vaccinated with Pneumovax23 have even stronger immune response to Prevnar13.”

Gabrielle Gaultier, a PhD student, is assisting Ulanova on this project. Her role is to collect blood samples from patients, isolate cells from the blood, and quantify the results.

“We hope our research will contribute to determining an optimal pneumococcal immunization schedule to better protect patients with severe chronic kidney disease against serious pneumococcal infections,” she says.

Gaultier hopes to use this experience to pursue a post-doctoral position in the fields of immunology and microbiology.

The last participants were immunized in February 2019. Ulanova and her group are now into the laboratory phase of the work, analyzing this data. She hopes results can be published within the year.

McCready — who has held numerous positions with NOSM and the Regional hospital — was the physician supervisor for these trials.

“These studies are an example of the synergies that can be achieved when clinicians collaborate with scientists and we are both motivated by trying to help patients from Northern Ontario,” he says.

This study was supported by Pfizer and the Northern Ontario Academic Medicine Association’s Innovation fund.

 

Story and photo by Julio Heleno Gomes, originally published in The Chronicle Journal Research in Action Series, April 7, 2020.

Photo:

Dr. Marina Ulanova and Lakehead University graduate student Gabrielle Gaultier have been studying the immune response of patients with severe chronic kidney disease to a certain type of vaccine.