Lyme-disease lookalike baffles CDC

St. Petersburg Times - St. Petersburg,FL,USA
Dr. John Sinnott, an infectious disease expert from Tampa, was vacationing in Key West when a man asked him to take a look at a strange rash.

The man's rash looked like the red "bull's eye" rash found in Lyme disease. But why would a disease most common in the Northeast turn up in a man who hadn't left Key West in months and couldn't remember getting bitten by a tick?

Lyme disease is rare, although not unknown, in Florida. But Sinnott decided the man probably had another disease, one doctors know less about: Southern Tick-Associated Rash Illness, or STARI.

Doctors think that, like Lyme disease, STARI is caused by a bacterium spread by tick bites. It causes a rash and is treated with antibiotics.

The bacterium, Borrelia lonestari , has been found in lone star ticks. It's related to Borrelia burgdorferi , which causes Lyme disease and is found in deer ticks. But they have been unable to grow the bacterium in a lab, aren't positive it causes STARI, and still have many questions about the disease. The federal Centers for Disease Control and Prevention wants to learn more about STARI, and is asking doctors across the Southeast to provide specimens for study.

"I don't think anyone knows how much STARI there is and how much Lyme," said Sinnott, director of the Florida Infectious Disease Institute at the University of South Florida. "We may have more STARI than Lyme."

Anywhere from 15 to 72 cases of Lyme disease have been reported in Florida annually over the decade ending in 2003, according to state health department statistics. But nobody is sure how many cases of STARI there are. Doctors aren't required to report it.

"I believe most things called Lyme disease in Florida are this separate disease," said Dr. N. Lawrence Edwards, vice chairman of the medicine department at the University of Florida College of Medicine. "I have seen Lyme ... but it's almost always in patients who summer in Connecticut or Maryland, and shortly after leaving come down with the symptoms."

That doesn't mean Lyme disease doesn't happen in Florida. Some doctors think the cases reported to the state are only a fraction of the real number. And the disease made the news recently when Florida State University officials said FSU quarterback Wyatt Sexton had been diagnosed with Lyme. That news followed Sexton's hospitalization under the Baker Act after he was found lying in the road, claiming to be God.

Such neurological symptoms as part of Lyme disease are unusual.

"Delusional activity is not something I've seen described," Edwards said, but cautioned that he doesn't know details of Sexton's case.

Lyme can cause cognitive disorders, the CDC says. Two years ago, novelist Amy Tan reported repeatedly hallucinating that a naked man was approaching her bed, as well as memory loss and other cognitive problems before she was diagnosed with Lyme.

Meanwhile, scientists at the federal Centers for Disease Control and Prevention last year started a new study of STARI. They're asking doctors across the Southeast to do skin biopsies of patients with tick bites and rashes that appear to be STARI and send them specimens.

In 2001, doctors found the lonestari bacterium in a skin biopsy of a patient with a STARI rash. The patient, who was treated with antibiotics, had been exposed to ticks in North Carolina and Maryland.

If doctors can isolate more samples of the bacterium from patients with the STARI rash, that would prove a more definite link, said Larissa Minicucci, a CDC epidemiologist in Colorado.

The bacterium "has been isolated from some lone star ticks, but we don't have a good correlation with that and the illness," Minicucci said.

Doctors think STARI doesn't cause the same complications as Lyme, but that's not certain, either.

Lyme disease cases in Florida often exhibit strange symptoms, said Carina Blackmore, the acting state public health veterinarian. Sometimes patients don't seem to have the classic rash. Often they're sick enough to be hospitalized, generally because they're diagnosed late.

"We want to understand Lyme better than we do in this state," Blackmore said. "We know it's here, but for some reason it's not behaving the same way it is in Connecticut and other states, and we don't quite understand why."

STARI might be a piece of the puzzle, she said.

"Maybe that's why we have a hard time diagnosing Lyme - that is it's not Lyme, it's Lyme-like disease," she said.