Researchers want to interview donors about their medical history to examine what they say is probably a previously unknown "auto-immune response" linked to the lung condition.
Citing privacy concerns, however, the Sundsvall District Court earlier this year denied researchers access to the names of the donors, stifling efforts to prevent further deaths.
Researchers have since appealed the decision, arguing that no donors would be put at risk as Karolinska itself strictly safeguards privacy.
The researchers believe about 1,000 donors should be interviewed, as each one could statistically be linked to about 14 cases of illness.
"You have to assume that a blood donor, who has done a good deed for society and for other people, would find it very odd that we, out of respect to the donor, would put our heads in the sand and let this continue,” Karolinska wrote in its appeal.
“They would without doubt be very upset if the blood donation centres (Blodcentralen) do not do anything to stop this from happening again.”