My ex has an autoimmune disease called lymphangiomatosis. Biggest issue is tumors in her lungs. It's some bad shit. Doctors thought she just had pneumonia when she first got sick. I really freaked out when COVID came around. I hope she's doing ok.
My wife has this, she's had half a dozen lung collapses over the last few years as the nodules separate lung from lung wall. Long term it is bad, many people are on oxygen for life. It also affects mostly women, and is likely woefully under diagnosed.
https://rarediseases.org/rare-diseases/diffuse-pulmonary-lym...