We'll be honest, the first time lupus came to our attention was in 2014 when Selena Gomez announced she was suffering from the disease following a stint in rehab. Then again when the 25-year-old announced she was calling time out to focus on her health, due to side effects from the disease. Just this week Selena shared on Instagram a photo from hospital following a kidney transplant (poor Sel) and her struggle got us wondering. What is lupus exactly? So we got in touch with Dr. Tri Phan, Immunologist at the Garvan Institute of Medical Research and, well, asked him. Here's how our chat went . . .

POSUGAR Australia: Hi Dr. Tri! For those of us who have no clue what lupus is can you kindly enlighten us?

Dr. Tri Phan: Lupus is an autoimmune disease in which the body's immune system attacks different parts of the body. Typically the disease affects the skin, joints and kidneys. Patients may also have increased risk of miscarriages and pregnancy complications. Lupus is a chronic disease characterised by periods of relapses and remissions.

PS: What causes lupus?

Dr. Tri: We still don't know what causes the immune system to attack the body.

PS: That's not great.

Dr. Tri: Hormones are obviously important since it predominantly affects women. The environment is also important, particularly sun exposure. Genes are also important, but the likelihood is that it is a disease where multiple genes are involved rather than one genetic defect. Groundbreaking research at the Garvan Institute is beginning to unlock the possible causes. For example, one lab has shown that during an infection the immune system may make antibodies to fight the infection that cross-reacts with a part of the body. This 'molecular mimicry' or mistaken identity may explain why some cases are precipitated by a viral illness. Another lab is undertaking the mammoth task of sequencing the cells that are attacking the body to decipher their genetic code and determine what turned them on in the first place.

PS: Are there different types of the disease?

Dr. Tri: Yes, definitely! Lupus is what we call a heterogeneous disease. There are many different manifestations in both the severity and type of body parts affected. For example, some patients with renal lupus where the disease attacks the kidneys may require high dose chemotherapy to kill off the immune cells and rescue the kidney. On the other hand, some patients may only have mild joint symptoms and a skin rash which is managed with anti-inflammatory drugs and sun avoidance.

PS: Selena Gomez mentioned she underwent chemotherapy, what does that mean for her?

Dr. Tri: Yes, chemotherapy is used as a treatment for lupus when you become at risk of end organ damage. In cancer treatment, chemotherapy poisons cancer cells, but with lupus, chemotherapy is one of a few treatments. Chemotherapy treatment most likely means that Selena is at the severe end of the spectrum with lupus.

PS: So who does it commonly affect?

Dr. Tri: Lupus commonly affects young women — they make up 90 percent of patients — but it can also affect men. Most patients are between 15-45 years of age.

PS: Ugh, lucky ladies, hey? What are the symptoms of lupus?

Dr. Tri: Patients may have a number of symptoms depending on the severity of the disease and the parts of the body that are affected. Common symptoms include tiredness, fatigue, mouth ulcers, hair loss, painful joints and skin rash on sun exposed areas. Because these symptoms can be mild and non-specific patients may have them for some time before they seek medical attention. In other cases, the symptoms can be quite severe and come on suddenly.

PS: What does treatment look like? Can patients be cured?

Dr. Tri: There is no cure for lupus, which is why at the Garvan Institute we are trying to find what causes the disease. Treatment varies greatly because of the wide spectrum of disease severity, as mentioned before. Many patients are on a medication called Plaquenil and a steroid called Prednisone. Because Prednisone has a lot of side effects, patients are also often placed on so-called 'steroid-sparing' drugs to reduce the Prednisone dose. A number of new 'biological therapies' have been trialled for lupus, but so far the results have been disappointing.

PS: How can we reduce our risk of contracting lupus?

Dr. Tri: I'm not sure you can. We just don't know enough. It is only by doing research that we can find a cure for this debilitating disease. You can help by supporting our research at the Garvan Institute.

PS: Will do! Thanks Dr. Tri!

Image Source: Splash News Online