CHICAGO — Chicago Police Superintendent Eddie Johnson has told officers he will have a kidney transplant next week.

Department spokesman Frank Giancamilli says Johnson sent a letter to officers telling them that he’ll have the surgery Aug. 30 and that First Deputy Superintendent Kevin Navarro will lead the department in his absence. The department has said Johnson expects to be out of the office three to five weeks, but that he will be working from home and be in regular contact with his staff long before his return.

Johnson has battled for decades a potentially life-threatening inflammation of the kidneys and in January announced he was on a waiting list for a transplant. On Wednesday he told reporters that his 25-year-old son, Daniel Johnson, will be the donor of the kidney.