Dallas ? Franklin D. Roosevelt may not have had polio at all, but a paralyzing disease called Guillain-Barre syndrome, Texas researchers say in a study that calls into question all the history books and presidential biographies.

“We feel from the clinical evidence, which is all that exists, that it’s more likely that he had Guillain-Barre syndrome,” said Dr. Armond S. Goldman, emeritus professor of pediatrics at the University of Texas Medical Branch in Galveston.

But Goldman added: “There is no way we can rule out the possibility of poliomyelitis. We felt it was unlikely, but we weren’t there. We did not examine him. He had very fine physicians who were experts in their field who did.”

Goldman was the lead author of the study, published in today’s Journal of Medical Biography.

Roosevelt was diagnosed with polio at age 39 in 1921 after swimming at Campobello Island in Canada.

The researchers acknowledge that Roosevelt’s vigorous exercise preceding the illness, fever during the initial phase and permanent paralysis were consistent with polio.

But they say that Roosevelt’s age, the pattern of his paralysis and the pain he experienced all point toward Guillain-Barre syndrome.

Historians and others were skeptical.

“I think it’s a significant stretch,” said Dr. Marinos Dalakas, chief of the neuromuscular diseases section at the National Institute of Neurological Disorders and Stroke. Dalakas said Roosevelt’s fever and other factors would strongly indicate polio, and contracting polio at his age would be “unusual but not unique.”

“It is pretty amazing when people try to rewrite history,” said Martin Harmon, spokesman for the Roosevelt Warm Springs Institute for Rehabilitation in Warm Springs, Ga., where a polio-stricken Roosevelt used to bathe in the soothing waters.

“Obviously, the diagnosis at the time was in the middle of the polio epidemic. It would be hard for me to believe that the doctors could not recognize the same symptoms that he had among the rest of our population.”

Goldman stressed that the point of the study was not to criticize the doctors back then, and he admitted a different diagnosis “would not have changed a thing.”

“The treatments for Guillain-Barre syndrome did not come about until the latter part of the 20th century,” he said. “There’s no way for physicians to have known what to do even if they diagnosed it as Guillain-Barre syndrome.”