In the early 1990s, Dr. Neil Spector began experiencing odd symptoms.

At times, his heart would beat 200 times a minute. He also suffered crippling fatigue and had “brain fog” so intense he once gave a lecture and had no recollection of it.

Blood tests showed his body was producing high levels of antibodies, but specialists couldn’t determine what was triggering his immune system’s response.

“It said my body was mounting a defense against something,” Spector told Healthline. “They just kept chalking it up to stress.”

More symptoms began appearing — slow heartbeat, arthritis pain, and burning in his heels — but experts dismissed Spector’s theory that they could be signs of Lyme disease, the most common vector-borne infection in humans.

Spector’s symptoms began right after he moved from Boston to Miami, but Lyme disease is uncommon in Florida. Spector said he doesn’t remember ever having the trademark bulls-eye rash of Lyme disease.

Spector, an associate professor of oncology at the Duke University School of Medicine, had no formal training in Lyme disease, but that changed as he searched for an explanation for his symptoms.

“Unfortunately, I had to learn more about the disease than I ever cared to know,” he said. “I could have dropped dead at any moment. During that time, I developed two cancer drugs and traveled the world.”

Initial tests gave false-positive results, but later tests confirmed that Spector’s symptoms were caused by Lyme disease. He was given an aggressive course of intravenous antibiotics for three months.

“I don’t think I have Lyme disease anymore, but the damage to my heart was already done by the time I was diagnosed,” he said.

By 2009, only 10 percent of Spector’s heart was functioning and he underwent a life-saving heart transplant. He recently completed his second half marathon in six months, and detailed his story in the book, “Gone in a Heartbeat: a Physician’s Search for True Healing.”

Spector urges patients to be their own best advocates, just as he did as a medical insider.

“I just don’t think we understand chronic Lyme disease, and the only people suffering are the patients. Nothing in medicine is black and white,” he said. “There’s a significant portion of patients who fall through the cracks of the medical system.”

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