This article was originally published in the May 2023 edition of Héma-Québec’s Magazine. All issues of the Magazine are available here.

Rare blood bank: the compatibility challenge

Rare blood runs through the veins of very few people. In fact, an individual’s blood type is considered rare when it is detected in less than 0.1% of the population, which indicates compatibility with 1 in 1,000 people.

How do you find out that you have rare blood? “For example, when you have a blood test at a hospital, as part of a pregnancy follow-up, for instance,” explains Jessica Constanzo Yanez, senior erythrocyte immunology specialist at Héma-Québec. “When these patients are identified at the hospital, they are referred to Héma-Québec to confirm their status. And we also do testing among our blood donors.”

It is the antigens on the surface of the red blood cells that determine the blood type. In addition to the ABO and Rh blood type systems, which are well known within the population, there are over 600 lesser known antigens, some of which are very rare. Therefore, not surprisingly, the great challenge with rare blood transfusion is compatibility. However, when the need arises, finding a blood donor can prove to be a global race against time. If someone with rare blood receives a unit of regular blood, even from blood group 0 negative, an immediate or delayed reaction can occur. For some of these patients, depending on the rarity of the blood, worldwide searches must be conducted to find compatible blood, which can sometimes take weeks. Unfortunately, there isn’t always that much time...

This is why Héma-Québec, whose rare blood bank has about 2,000 frozen pellets of a number of rare blood types, would like to diversify that. The barrier to growing the bank is that Héma-Québec does not have the right to contact patients whose blood is known to be rare to ask them to donate blood or do a family study with their siblings. From this perspective, in January 2022 the organization launched its rare blood program as a pilot project in a few hospitals. The objective of this program is to create a partnership with hospital clinicians to raise awareness among patients with rare blood and to encourage them to contact Héma-Québec to donate blood and conduct a family study. By optimizing its bank, Héma-Québec wants to respond faster to requests for units of rare blood, most often from blood collected at its own donation centres.

“Often, when people learn that they have rare blood, they see it as a disease,” explains Constanzo Yanez. “But it’s not a health problem. These people are different from others and can help other people who have the same rare blood as they do.”

It is this spirit of mutual assistance, central to Héma-Québec’s mission, that motivated the 2022 launch of the rare blood program, which aims to make the province’s physicians and patients aware of the existence of rare blood and facilitate the recruiting of new donors.

As part of this partnership, Héma-Québec, when confirming the patient’s blood type after analysis in its labs, asks the physician who must meet with him/her to take the opportunity to give the patient an explanatory brochure. By signing a consent form, the patient authorizes Héma-Québec to contact him/her. It’s that simple!

As such, people with rare blood can help each other… and even save each other’s lives!