Over in Gabe's room, Gabe's airway is closing. Chase, Cuddy, and Foreman run in, and Chase takes a look inside Gabe's throat, which he reports has nodules. They'll need to intubate, but Foreman can't get the tube in. He keeps trying, and Gabe stops breathing. Chase grabs a scalpel to do a tracheotomy, and has just begun the incision when Foreman gets the tube through and Gabe is breathing again. Air Force One alternates between looking angry and looking very worried.
The Cottages follow House down the hallway, discussing why Gabe's throat closed up. It wasn't an allergic reaction to the antibiotics, since they switched medicines and the throat nodules didn't go away. House wonders what "Dr. Chase" thinks, and lets Chase get a few words in before interrupting to say he meant the other Dr. Chase. You know, the one House is using to antagonize one of the only people in the world who actually likes him.
There are now two Chases in the Differential Diagnosis room. Chase the Elder doubts the anthrax diagnosis, especially since Gabe's tell-tale rash hasn't turned black. Apparently, anthrax rashes get necrosis, which is nasty. Cameron supports the Elder's theory, because she's a bitch. Chase the Younger defends his theory, saying that the rash can take as long as two weeks to turn black. Chase the Elder sips his coffee. Chase the Younger makes an angry smirking face. House hasn't had this much fun watching a fucked-up relationship play out since the last episode of GH he watched. He puts Chase the Younger's diagnosis to a vote, and it gets no support. Therefore, it's time to figure out what else Gabe could have. Chase the Elder suggests sarcoidosis. They'll go with that.
Foreman and Chase inform Air Force One that the latest tests confirm a new diagnosis of sarcoidosis, which is making Gabe's lung and throat tissues swell. No one knows how it's caused or how Gabe got it, but they're going with it since, as Chase says, a "world-renowned" and personally-hated doctor is consulting on the case. That really shouldn't make anyone feel better, considering that House is supposed to be pretty well-known himself and, thus far, he's been way off. Foreman starts to hook up some anti-inflammatory medicine, but Chase notices something and orders him to stop. He turns Gabe's wrist over, and we see that his rash has turned black.