We don't get to see a scene of everyone in the conference room, wondering what House could possibly be doing in the bathroom for the last fifteen minutes. We join the scene already in progress, with House explaining it all: Gabe has leprosy. He got it from his father, who got it on the ashram. That explains the non-carpal tunnel syndrome. The leprosy weakened Gabe's immune system, making him more susceptible to the anthrax, and which then, in turn, accelerated the leprosy. Then, the antibiotics they gave Gabe for the anthrax killed the leprosy bacteria, which then entered Gabe's bloodstream, causing his own body to create antibodies that ended up attacking everything, just like an autoimmune disease. Therefore, everyone's theories were equally correct, yet still wrong. House tells Cameron to call the only leper colony in the "lower forty-eight," which is in Louisiana, as shouldn't surprise anyone (although I do want to know what the leper colony in Hawaii looks like and why everyone doesn't just live there). They'll send some thalidomide, which Cameron balks at until House reminds her that Gabe won't be having a thalidomide baby any time soon, since he is twelve. And male. And shut up, Cameron.
This leaves House and the two Chases. House excuses the Elder to talk to the Younger. He takes some pills as Chase asks him why everyone is all up in Chase's business today. House says that sometimes, when you know things about people, you care about them more. Plus, you feel superior to them. Chase asks if House will care about Chase more if he knows that Chase's dad abandoned him and his mother drank herself to death. House says he won't. Cameron might, though, so he can try her if he wants. And then House adopts a softer tone and says he knows that Chase hates his dad, but that he has something to tell him. He's about to, I assume, tell him about the cancer when Chase interrupts to say that he doesn't hate his dad, but that he learned that it hurts less not to care. If you don't expect any love or attention from your dad, then you won't be disappointed when you don't get it. "Okay," says House. "That's it?" Chase asks. "That's it," says House. And Chase leaves.