HARTFORD, Conn. - Patients who believe they suffer long-term problems from Lyme disease are claiming victory over a national doctors group. The Infectious Diseases Society of America has agreed to review its guidelines, which say there's no evidence long-term antibiotics can cure "chronic Lyme" disease - or even that such a condition exists.

The agreement settles an unprecedented antitrust investigation by Connecticut's attorney general over the matter. The doctors group makes clear that current guidance for treating Lyme disease remains in place.

But that didn't stop claims of success by the attorney general and people who believe they suffer long-term effects of the tick-borne disease.

"It's a great victory for patients," said Pat Smith, president of the Lyme Disease Association, a national nonprofit group based in New Jersey. "It's time that Lyme patients got the respect they deserve."

The agreement, announced Thursday, calls for the doctors group to form a new panel of experts to review standards for treating Lyme disease. The Infectious Diseases Society says it agreed to the deal in part because the panel must be made up of doctors and scientists.

Lyme disease can be hard to diagnose with its vague, flu-like symptoms; the most obvious sign is its trademark round red rash. Usually, it's easily cured with a few weeks of antibiotics. Those not promptly treated can develop arthritis, meningitis and other serious illnesses.

About 20,000 new cases of Lyme disease are reported every year, but experts believe the annual total may be five times higher.

Connecticut leads the nation in reported cases and has been a battleground in the national debate over treatment. Lyme disease is named after the Connecticut town of Lyme, where the illness was first discovered in 1975. And the state is home to a number of people who claim they suffer long-term problems from Lyme disease - problems that many doctors are unable to confirm or treat.

The Infectious Diseases Society says it's never been proven whether these patients still have Lyme disease or something else. The group continues to defend its standards, which say short-term antibiotics are effective for nearly all patients. Long-term antibiotics are unproven and potentially dangerous, because overuse of the drugs can lead to drug-resistant infections, the society says.

"We are confident that our guidelines for the diagnosis and treatment of Lyme disease represent the best advice that medicine currently has to offer ... and we look forward to the opportunity to put to rest any questions about them," said Dr. Donald Poretz, the society's president.

The society will consider a variety of scientific evidence and determine whether the 2006 guidelines are justified or need revision.

The guidelines are important because they discourage adequate treatment, advocates of chronic Lyme sufferers say. Perhaps just as significant is that insurance companies refuse to pay for long-term antibiotics to treat chronic Lyme.

"We are delighted with this settlement," said Diane Blanchard of Greenwich, who said she was sick with Lyme disease for 10 years before a long-term antibiotic treatment relieved her symptoms in the late 1990s.

"The IDSA guidelines are now clouded by this decision. My greatest hope is that patients will regain their right to treatment," said Blanchard, now co-president of the advocacy group Time for Lyme.

Philadelphia-based health insurer Cigna Corp. said it is reviewing the agreement to see if any changes in policies are needed. Cigna covers up to 28 days of intravenous antibiotic therapy for Lyme disease and, like many insurers, cites the Infectious Diseases Society's guidelines in its coverage plan.

Cigna does not pay for "repeated or prolonged" courses of antibiotics, saying they are "experimental, investigational or unproven."

Connecticut Attorney General Richard Blumenthal and advocates say the agreement is the first time the medical establishment has bowed to the pressure of a potential court fight and agreed to re-evaluate care standards.

"My main goal all along has been a process that is fair, open and free of conflicts of interest," Blumenthal said.

Blumenthal said his investigation found that some of the 14 experts who approved the 2006 guidelines got consulting fees, research grants and stock ownership from drug companies and other businesses that have a stake in the treatment and diagnosis of Lyme disease.

He would not name the panel members or the companies. He said the backgrounds of the new experts looking at the guidelines will be checked for any potential conflicts.

The issue involves antitrust law, Blumenthal said, because the panel excluded some opinions and evidence that may have supported other treatments in development, including vaccines.

Blumenthal's office did not take a position on the proper treatment of the disease or whether chronic Lyme disease exists.

The Infectious Diseases Society denied any conflict of interest.

"Panel members do not stand to profit from any recommendation in the guidelines," the group said in statement. "In fact, the panel members denied themselves and their colleagues an opportunity to generate a significant amount of revenue when they recommended against expensive, repeated, long-term antibiotic therapy."