"I am requesting support and prayers be offered me and my sister, and my only immediate family @denisedowse," her sister wrote in an Instagram post made to Dowse's official account. "She is currently in the hospital in a coma brought on by a virulent form of meningitis. Her doctors do not know when she will come out of the coma as it was not medically induced."
"She is a vibrant actor and director that should have many years ahead of her. Thoughts, prayers and support are greatly appreciated," she added.
Her "90210" co-star, Ian Ziering wrote in the comments, "Sending prayers and hopes for better days ahead."
CNN has reached out to a representative for Dowse for comment.
Dowse is best known for her role as Mrs. Yvonne Teasley on "90210" from 1991 to 2000. Her credits also include roles on the CBS series "The Guardian" and in the HBO series "Insecure."
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