Transcript for Selena Gomez reveals she underwent kidney transplant
The latest on Selena Gomez. We learned why she took time off,he was getting a kidney transplant from one of her close friends and Deborah Roberts has the details. This is a big surprise for her fans. Solving the mystery about why the singer has kept such a low profile lately. The story first broke on the celebrity news site the blast last night and the support for Gomez is flooding in on social media this morning after she revealed the deeply personal news about her battle with lupus. Just hours ago, Selena Gomez posting the surprising news to her Instagram page. I needed to get a kidney transplant due to my lupus. The pop sensation also posting these two close-up views of the scar from her surgery. Her kidney donor one of her closest friends Francia Raisa pictured holding hands with her in the hospital. Raisa, the star of the "Secret life of the American girl." The pair seemingly inseparable on social media. Even on the road. ??? Gomez thanking her friend in the post writing, there aren't words to describe how I can possibly thank my beautiful friend Francia Raisa. She gave me the ultimate gift and sacrifice by donating her kidney to me. The singer has been suffering from the autoimmune disease lupus and its complications telling billboard magazine the illness even forced her to call off tour dates in recent years. I've been through stuff and I think that it's been able to test me as a person. Reporter: An estimated 1.5 million Americans suffering from lupus, which can aggressi aggressively attack body tissue and organs. Often leading to kidney disease. Gomez who says she posted this news to tell her fans why she was laying low in recent months seems optimistic writing, lupus continues to be very misunderstood but progress is being made. And such progress for her. Selena is far from alone though in her battle. According to the lupus research alliance, 90% of those diagnosed with lupus are young women. But she is obviously so determined to get back into her career she was spotted on the streets of New York City recently filming a new woody Allen movie. Guys. Thank you, Deborah. So much for that. Dr. Jen Ashton joins us now at the desk. Good morning. You we heard that piece and lupus is very misunderstood. What is the connection between lupus and kidney transplants. So lupus is an autoimmune disease where literally your body's own organs or joints or skin because that's an organ are attacked. Because the body senses it as kind of a foreign -- we don't understand why but lupus Nevada fright physical is when it attacks the kidneys is a serious and potentially life-threatening condition. When someone's kidneys start to fail they are left with two options, hemodialysis, a filtration of the blood that can leave them alive or organ transplantation. Unusual to see someone this young get to the stage of kidney failure where an organ transplantation is even an option. But it's a great opportunity to talk about, you know, with kidney transplantation because we have two. You can do a living directed donation. Is it a cure? It can -- it's not a cure for lupus. That's important but it's a cure for the kidney failure. Interestingly with kidney transplantation in most cases the diseased or dead kidney is not removed so you leave the two kidneys in there and the transplanted kidney is actually put deep in the pelvis, just some numbers that are important to know, 15,000 kidney transplants done in this country every year. 3,000 people are added to the kidney transplant list every month. 13 patients die daily waiting for a kidney transplant and every 14 minutes someone is added to the kidney transplant waiting list. What is the recovery for Selena? What's the recovery for her donor and how do they have to adjust their life for the future. The donor is important. Even though it's a straightforward surgery it's a major surgery. So they both have to recover. Usually three to seven days in the hospital. The donor can go home probably a little bit sooner. The recipient in this case Selena Gomez has to be monitored very closely for rejection. The chances of rejection are less when you get a kidney from a living donor but it's still a possibility. And the survival rates are excellent. They're not perfect but they're excellent and then, you know, again, the condition of the patient is the most important thing. You have a young, healthy patient generally they're going to do better. Part of the reason why they probably waited because it happened this summer. Not just happening overnight. It's great. Just to have this conversation on both sides. Organ donation, go to donate life on the web and you can read about how you can sign up to be an organ donor. Thank you, Jen.
This transcript has been automatically generated and may not be 100% accurate.