April 27, 2021- 11:31 a.m.
The rare clotting disorder seen after the Johnson & Johnson vaccine might not only be a problem for women.
UC San Francisco said that a healthy and athletic Bay Area man in his early 30s developed this unusual syndrome – called vaccine-induced thrombotic thrombocytopenia – after being inoculated with the J&J COVID-19 vaccine on April 8.
This is the first reported male case of the syndrome, called VITT, since the vaccine began widespread public distribution. One similar case was identified in a 25-year-old man who had received J&J’s vaccine during the company’s clinical trials, but evidence was insufficient to attribute his symptoms to the vaccine.
“This is not a ‘women’s club,’ only,” said UCSF’s Dr. Andrew Leavitt, who treated the patient. “As a provider, when you see a patient, you need to make sure you’re not limiting your thinking.”
The Johnson & Johnson vaccine remains extraordinarily safe, add experts. Nearly eight million Americans have received it, without incident, and are now protected from the far more dangerous coronavirus. There’s only a 0.008% risk of developing this dangerous side effect.
But the new case deepens the mystery of the syndrome’s demographic pattern. Scientists ask: Is there truly a gender difference, due to underlying biological differences, or were the cases in women just a statistical fluke?
Before this, all 15 cases of the deadly blood clots have been in women. Of those, 13 occurred in women between the ages of 18 and 49 years. The other two cases were in women ages 50 to 59.
Cases of the syndrome linked to the AstraZeneca vaccine, which contains comparable ingredients, are also predominantly female.
“Right now, there’s a predominance” in women, said Leavitt, director of UCSF’s program for noncancerous blood disorders. “But these are very small numbers. I don’t think that people who really know statistics would say: ‘It doesn’t affect men.’ ”
Prematurely linking the vaccine to women could mean that men aren’t alerted to the potential problem, and, if they sicken, doctors may misdiagnosis it.
The U.S. Centers for Disease Control and Prevention has been cautious in making the gender link. After long deliberation on Friday, a CDC committee voted to recommend revised labeling on the J&J vaccine that cautions: “Most cases of thrombosis with thrombocytopenia reported following the (J&J) COVID-19 vaccine have occurred in females ages 18 through 49 years; some have been fatal.”
Federal health officials then lifted their suspension of the vaccine, clearing the way for immediate resumption of one-shot inoculations.
The UCSF patient developed escalating pain in his lower back and leg on April 16, went the UCSF’s emergency room and was hospitalized on April 21. He received the recommended therapy — intravenous immune globulin, the anticoagulant argatroban and prednisone — and is now recovering. He is expected to be discharged within a few days.
His case did not fit the textbook clinical criteria seen in the other cases.
While his blood work showed signature low levels of platelets and fibrinogen seen in other patients with this syndrome, there was no identifiable clot. But he had very high levels of a protein called D-dimer. D-dimer is left over when your body breaks down blood clots; it’s like the wood dust that floats in the air after sawing lumber. Elevated D-dimer levels told his doctors that he had developed clots, but that his body had successfully dissolved them.
The link between VITT and vaccines is perplexing scientists. Unlike traditional blood clots, the syndrome is combined with a low platelet count. While this unusual aggregation is sometimes seen in patients who get the blood thinner called heparin, these patients aren’t on that medication.
Scientists are racing to identify what’s causing the problem. So far, they’ve identified a major clue: So-called “autoantibodies” formed in response to a protein called Platelet Factor 4, according to Leavitt.
So now the question is what’s causing these new antibodies to be generated? Does the vaccine trigger a misguided response by the immune system?
Other autoimmune disorders — characterized as conditions in which the host’s immune system mistakenly attacks itself, such as rheumatoid arthritis and lupus — are known to be nearly twice as common in women. The exact mechanism of such autoimmune conditions is not well understood, but they appear to be linked to hormonal changes. Many autoimmune disorders tend to affect women during periods of extensive stress, such as pregnancy, or during a great hormonal shift. Researchers are now attempting to identify the underlying factors.
But the condition, while less common, is no less serious for men.
“This guy did all the right things,” said Leavitt. “First he thought it was just a cramp, but it got out of hand. So he showed up for care.”