Antiphospholipid syndrome is a condition in which the immune system mistakenly creates antibodies that attack tissues in the body. These antibodies can cause blood clots to form in arteries and veins. Blood clots can form in the legs, lungs and other organs, such as the kidneys and spleen. By: https://www.instagram.com/tv/Cb_54eLDw9K/?igshid=YmMyMTA2M2Y=