The Kerrys in 2010. (Evan Agostini / AP)

It remains unclear what caused Teresa Heinz Kerry to fall ill this weekend — but her condition is improving, and doctors have ruled out some of the scarier possibilities.

A spokesman for Secretary of State John Kerry said Tuesday that while his wife, 74, remains at Boston’s Massachusetts General Hospital after falling ill with seizure-like symptoms, physicians have ruled out a brain tumor, stroke or heart attack as the underlying cause.

Otherwise, the family is not planning to release anymore information until she leaves the hospital, spokesman Glen Johnson said in a statement to reporters. With his wife in stable condition, Kerry was headed to D.C. to kick off Wednesday’s U.S.-China Strategic & Economic Dialogue; other relatives remain at the hospital with her.

Earlier: Teresa Heinz Kerry: The quiet presence behind the secretary of state, 7/8/13

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