CHICAGO (AP) — Doctors say Chicago Police Superintendent Eddie Johnson’s kidney transplant was a success and he is expected to leave the hospital this weekend.

At a Thursday news conference at Rush University Medical Center, doctors said Johnson’s 25-year-old son, who donated his kidney to his father, is expected to leave the hospital Thursday afternoon. Both Johnson and his son are listed in good condition.

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Dr. Martin Hertl said Johnson was sitting up in bed and had started answering emails Wednesday night. Hertl and fellow transplant surgeon, Dr. Edward Hollonger Jr., said they expect Johnson to make a full recovery.

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And Mayor Rahm Emanuel was spotted paying the top cop a visit on Thursday following his surgery. He did not speak to reporters.

Mayor Emanuel visited Police Supt. Eddie Johnson following his kidney transplant operation. (CBS)

Johnson disclosed in January that he has had kidney inflammation and was on a transplant list. On Thursday, doctors said Johnson’s kidney function had been at 10 percent it wouldn’t have been long before he needed a transplant or dialysis.

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