Usually conditions of heart, kidney, liver or low protein or severe anemia, which cause ankle
and leg swelling cause both ankles to swell. Hence if both ankles
and leg are
swelling then you will need to get heart function assessed by ECHO and EKG, TMT, get kidney and liver function tests done and get a complete blood picture for anemia. Low sodium in blood, hypothyroidism and malabsorption syndromes causing low protein in blood have to be looked into.
Hope this helps.