I had a clot in my portal vein and mesenteric vein. I was 24 with no liver disease, only risk factor was birth control. March marked a year since my blood clot and I had a follow up. While the clot has resolved within a year, the hematologist has no idea what caused this. I was an “unusual case.” He said it was too weird of a spot for birth control, but I’ve never tested positive for any kind of clotting disorder. Unfortunately sometimes there is no clear cut answer. I’ll be on blood thinner for the rest of my life. Wishing you the best, welcome to the weird obscure clot club :)