Monica Lewis, the 5-year-old Silver Spring girl who is waiting for a liver donor so that she may undergo a transplant, took a turn for the worse over the weekend and yesterday was flown to Children's Hospital of Pittsburgh where she will wait to be matched with a liver donor.

In a telephone conversation yesterday, Monica's father, Mike Lewis, said his daughter had undergone several blood transfusions at Holy Cross Hospital in Silver Spring over the weekend. Doctors advised Lewis and his wife Pat that their only child needed to be in a major medical center. The couple rented a private plane and flew Monica to Pittsburgh yesterday afternoon.

"Our intention is to stay here until she gets a transplant," said Lewis, who is publisher of a U.S. Chamber of Commerce newspaper. Children's Hospital spokesman Dick Riebling said yesterday that a donor has not yet been found for Monica.

Another area child also at Children's, 18-month-old Candi Thomas of Accokeek, Md., underwent a liver transplant last month. She is recovering and yesterday was reported in fair condition.

Monica Lewis suffers from a hereditary disorder called Alpha-1-Antitrypsin, which causes severe scarring of the liver, rendering it almost useless in aiding digestion and cleansing the blood of poisons. Dangerous internal bleeding is another complication.

Last spring Monica was evaluated by liver transplant specialists at Children's and by July was at the top of the hospital's list of children in critical need of a new organ.

Mike Lewis said his daughter is still able to walk and move about, but her speech has become incoherent. Yesterday he said, "She doesn't have much time."