Cane and Able
"Cane and Able" is the second episode of the third season of House and the forty-eighth episode overall. The episode's title is a pun referencing the biblical siblings Cain and Abel as well as House's cane and his reinforced confidence in his ability as a diagnostician.
Plot
House's ego has taken a blow believing he failed to diagnose his last case, and it's affecting him physically. He is in pain again, although he denies it. House's new case is seven-year-old Clancy, a product of in vitro fertilization, who's been admitted to the hospital with rectal bleeding and proclamations of being tortured by aliens. As the team runs tests on him, they discover the same test is giving conflicting results. House thinks the child is having nightmares with the one symptom of having a bleeding disorder. The tests on the bleeding disorder are first negative and then positive, leading both Chase and Foreman to think that the other made a mistake. The tests keep going back and forth. When Clancy claims to have a tracking device in the back of his neck, Chase discovers an unknown metal object exactly in that spot, and the team is not quite sure what to think. House, however, surmises from his chart the metal in the back of his neck is a surgical pin that had not been completely removed several years prior and had migrated via the circulatory system.