Dave Tierney never suspected that tick-borne illness might be responsible for the intermittent fatigue, pain, itching, cramping, balance problems and other issues that bothered him for years. Nor did it occur to any of the more than 20 Triangle-area doctors Tierney sought help from. Tierney, a former Marine, had at least two tick bites while stationed at Marine Corps Air Station Cherry Point in the early 1990s. He is originally from Connecticut, where Lyme is prevalent.

Tierney's symptoms worsened in 2002. He was working in a ground position for Delta Air Lines at the time, having lost his pilot's job in layoffs that followed the terrorist attacks of Sept. 11, 2001. At times he was so exhausted he could hardly move.

"It was devastating," said his wife, Dotsy Tierney. "He's always done everything -- he's run the family. And he would just sit and stare."

Tierney's doctors settled on a diagnosis of multiple sclerosis starting in December 2006. They based it on imaging scans that showed lesions in his brain. Tierney consulted six neurologists. Half said he had MS, half said he didn't.

Sitting at home on disability, Tierney kept searching for answers. In July, just a month after Tierney left his job, his search led him to Beth Jordan and the N.C. Lyme Disease Foundation. The more he learned, the more a diagnosis of chronic Lyme seemed to fit. Brain lesions, he learned, are sometimes caused by Lyme bacteria.

At Jordan's recommendation, Tierney contacted Dr. Joseph Jemsek of Huntersville, near Charlotte, a Lyme doctor who was disciplined by the N.C. Medical Board over his treatment of patients with chronic Lyme. Tierney said Jemsek spent about two hours going over his medical records and listening to his story. At the end of that visit, Tierney said, Jemsek seemed convinced he had Lyme.

Tierney took out a low-interest loan for $20,000 to pay for treatment, including three months of intravenous antibiotics. Since then, Tierney has successfully appealed to his health insurer, which he expects to reimburse him for most of the cost.

Tierney suspects his recent claims history helped his case. His medical bills for MS treatments in 2007 exceeded $120,000. Tierney expects to take oral antibiotics for at least another six months, but, he said, it'll be cheaper than MS drugs.

"I feel better," Tierney said. "And I feel vindicated."