Dr. Lipman said that as the team had studied her blood samples, the pieces began to fall into place, and they realized that she appeared to have the same problem that they knew had been occurring in Britain and Europe after patients received the AstraZeneca vaccine, mostly in young women. They switched from heparin to another blood-thinner and began following guidance provided by doctors in Britain who had treated AstraZeneca recipients with a similar disorder.
Hoping for more information about the condition and any possible connection to the Johnson & Johnson vaccine, Dr. Lipman called an emergency number at the Food and Drug Administration. It was a weekend, and he said the person who answered told him that no one was available to help and that the line had to be kept open for emergencies.
“I thought this was an emergency,” Dr. Lipman said. “She hung up on me.”
He called back, to ask how to reach Janssen, which makes the Johnson & Johnson vaccine. That information was not available, and he said the person who answered had also told him that the F.D.A. could not provide advice on patient care.
An F.D.A. spokeswoman, Stephanie Caccomo, said in an email, “We’ll look into this further to ensure physicians calling F.D.A. for assistance receive the help they are seeking.”
Dr. Lipman said that the pharmacist at his hospital had submitted a report online to the Centers for Disease Control and Prevention in early April but that the agency had not contacted him to ask about the case until this week. The agency declined to comment on whether it had communicated with Dr. Lipman, a spokeswoman, Kristen Nordlund, said by email.
At a meeting on Wednesday of a C.D.C. advisory panel, Johnson & Johnson and Dr. Tom Shimabukuro, a safety expert at the agency, both presented data about the young woman in Nevada. After the meeting, Nevada officials issued a statement saying the meeting was the first time they had learned of a case in their state — they had previously told the public that no cases had been reported — and they were asking “federal partners” why the state had not been informed.
At the Nevada hospital, an interventional radiologist passed a tube through blood vessels and on into the young woman’s brain and used a device to suction out the blood clots. More clots formed later, and he performed the procedure again.