Flinders University researchers have played a key role in identifying the underlying cause of a novel, chronic blood clotting disorder.
A new blood clotting disorder has been identified, with Australian researchers playing a vital part in determining the underlying mechanism.
The research, published in the New England Journal of Medicine, describes five patients who displayed unusual and persistent blood clotting after receiving high doses of blood thinners while being treated in New Zealand, Germany, Spain, France and Canada.
All patients displayed low serum levels of antiplatelet factor 4 antibodies similar to those seen in cases of vaccine-induced immune thrombocytopenia and thrombosis (VITT) – which had previously been linked to the AstraZeneca covid vaccine – for over a year.
The ongoing presence of the antibodies suggested there was an underlying pathological process involved, rather than these patients experiencing a short-term reaction to a vaccine or adenovirus infection.
Dr Jing Jing Wang (PhD), a senior research fellow from the Flinders Health and Medical Research Institute and co-first author on the new publication, led efforts to examine the antibodies to determine how the new clotting disorder was different from “classic” VITT cases.
“By using our proteomic approach developed at Flinders Proteomics Facility, we [proved] that the monoclonal (M) proteins are the pathological VITT-like antibodies,” Dr Wang told media.
“Low-level serum M (monoclonal) protein are often identified in patients who have VITT-like MGTS [monoclonal gammopathy of thrombotic significance]. Despite these M proteins being in relatively low concentrations, they are highly pathological VITT-like proteins, which explain the patients’ severe symptoms.”
“We all remember those difficult times during the pandemic when the vaccine was linked to the rare, sometimes lethal clotting complication called VITT,” said SA Pathology’s Professor Tom Gordon, a clinical immunologist, rheumatologist and immunopathologist.
“This was initially thought to be self-limiting over days and weeks. [But] the major jump in knowledge coming from this new study is that a highly similar chronic condition – over months and years – can occur with patients presenting with intermittent clotting episodes,” he said.
While thrilled by their discovery, the team are already looking forward to what happens next.
“By understanding how to diagnose VITT-like MGTS, we can develop more effective treatment strategies that go beyond traditional anticoagulation,” said co-first author Emeritus Professor Theodore Warkentin, from McMaster University in Canada.
Researchers anticipate these findings will change how doctors test and treat patients who present with unusual or recurrent blood clotting, which may lead to improved outcomes.
“We propose that diagnostic testing for unexplained chronic prothrombotic disorders be expanded to include testing for anti-PF4 antibodies, as well as testing for M proteins,” the researchers wrote in the conclusion of the manuscript.
“[The anti-PF4 monoclonal paraproteins] are usually detectable on standard, commercially available PF4-dependent ELISAs, but they cannot be identified on rapid assays for heparin-induced thrombocytopenia antibodies.”
