PITTSBURGH (AP) _ Philippines President Ferdinand Marcos had two kidney transplants during periods of speculation that he was gravely ill, according to prominent Filipino physicians quoted in a report published Sunday.

The transplants were performed in August 1983 and November 1984 in the Philippines National Kidney Foundation in Manila, The Pittsburgh Press quoted Dr. Enrique Ona and Dr. Potenciano Baccay as saying in a copyright story.

In August 1983 and November 1984, there were rumors that Marcos was gravely ill. After the 1983 rumor died down, Marcos said he suffered only allergies.

Marcos, 68, who celebrated his 20th anniversary Saturday as ruler of the Phillipines, has called presidential elections for Jan. 17. He has insisted for the last three years that his health is good.

Baccay, one of Marcos' personal physicians and vice president of the National Kidney Foundation, was found stabbed to death Nov. 2, shortly after he spoke to the newspaper. Police said he was kidnapped and murdered by Communist rebels.

Ona is director of transplantation at the Philippine National Kidney Center.

Dr. G. Baird Helfrich, director of renal transplants for Georgetown University Medical Center in Washington, D.C., and Dr. Barry Kahan, director of transplantation at Houston's Hermann Hospital, performed the surgery in Manila, Baccay told the newspaper.

Helfrich said he was in the Philippines in August 1983, and Kahan said he was in Manila in the fall of 1984 and ''did a number of transplants on Filipino patients.''

In an Oct. 19 interview on the CBS-TV program ''Nightline,'' Marcos said he had shrapnel in some organs from war wounds.

''One of them was the kidney,'' he said. ''But they worked out on this. Your doctors are so good that now I am better than a normal person with two kidneys.''

When asked by the Press if Marcos was one of his patients, Kahan said: ''I have no comment. Is this really news at this stage?''

Helfrich also refused to comment, citing patient confidentiality, said the Press.

''If the first family chooses to release anything it's their decision, otherwise it's a patient confidentiality issue I will respect,'' he said. ''This is not a subject I'll discuss,''

Marcos rejected the first kidney transplanted by Helfrich and Kahan performed the second transplant, the Filipino doctors told The Press.