Former prime minister Ariel Sharon's condition at Sheba Medical Center has taken a turn for the worse in the past two days, the hospital announced on Sunday night. His kidney function has declined, causing serious edema (swelling due to accumulation of liquids) in his body. In addition, "changes in his brain tissue" have been noted and are being monitored, the hospital said. The 78-year-old Sharon, who suffered a major hemorrhagic stroke on January 4, was hospitalized at Jerusalem's Hadassah University Medical Center for five months and then transferred - in a deep coma and attached to a respirator - to Sheba's respiratory rehabilitation unit at Tel Hashomer. Doctors there had hoped to wean him from his respirator, but they have not succeeded in advancing his condition. His further decline is worrisome. Doctors who were familiar with Sharon's case at Hadassah but who have not been informed about his condition since he was transferred said that a decline in kidney function could be treated with diuretics, but if not reversed, it would require hemodialysis to remove the toxins from his body. His condition, they said, could lead to multiple organ failure if it continues to decline. Sharon's son and other family members are updated on an ongoing basis about his condition, the hospital said and are at his bedside on a permanent basis.