Treatment for petechiae on the legs and ankles depends on the underlying cause. If petechiae are due to a low blood platelet level or clotting, a transfusion is necessary, according to the Virtual Medical Center. If they are due to leukemia or cancer, treatment involves radiotherapy, chemotherapy or hormone treatment.
A patient with petechiae due to injury needs no treatment, and the petechiae resolve on their own. Applying cold packs to the injury prevents development of additional petechiae, claims the Virtual Medical Center.
Petechiae are red, brown or purple spots that appear on the skin due to internal skin bleeding. They commonly appear in a cluster and may look like a rash, explains Mayo Clinic. Causes of bleeding into skin include injury, allergic reactions, blood infections and autoimmune disorders, says Healthline.