Dr. Sebastian Charles emerges from a plane in a remote African village. He's arrived with tuberculosis medicine for the villagers, who greet him warmly. Back in the states, Dr. Charles gives a presentation to the board of Stoia-Tucker Pharmaceuticals and implores them to provide more medicine from the poor. During the presentation, Dr. Charles collapses and seizes.
Charles thinks he has TB and Cuddy agrees with him. House quickly declares that it's not TB. Dr. Charles asks to sit on the differential with the rest of the team. Charles is positive that he suffers from TB and his backers only want the second opinion. Dr. Charles orders himself a round a tests to confirm it.
House calls his team back to the office to figure out other illnesses. Chase notices an abnormal heart rhythm which would explain the man passing out. Cameron orders a stress test and an echocardiogram, but the results are normal. The EKG isn't. House suggests a tilt table test, which Foreman says never works. House assures him that it will.
The test is going fine until House turns the speed way up. Charles complains that he's about to throw up and faint. The new speed reveals an abnormal P-R interval. Charles is going to need a pacemaker, and surgery is scheduled for the afternoon.
Cameron seems quite impressed with Charles's sense of being a do-gooder. He tries to persuade Cameron to join him in Africa and offers to discuss it over dinner. But during a brief walk, Charles feels faint, then vomits and passes out.
The team reconvenes to figure out new problems. Foreman thinks the headaches point to a neurological source and he offers up acoustic neuroma, which is a brain tumor that causes all of these problems. House orders an MRI. Charles slides into the machine. Cameron sees that the MRI is clear, showing no tumor. But the PPD she implanted two days to test for TB is clearly positive.
She reports her findings to House, who's unimpressed. He knew Charles would have TB because he's been in the jungle so long. He complains that now that Cameron has proven Charles's diagnosis for him, he'll refuse to submit to any more tests. She counters that every symptom screams TB.
In Charles's room, Cameron delivers a cupful of pills for his resistant strain of TB. Looking at the pills, he realizes that two years' worth of pills would cost $10,000. Thinking of poor mothers who can't afford any pills, Charles decides not to take them. He thinks if he dies, people might pay more attention to his story and the problem with big pharmaceutical companies.
House goes over the symptoms of increased heart rate, night sweats and a loss of consciousness. If it's not a tumor, then what else could it be? Foreman counts down the list: Fabry's, autonomic dysregulation syndrome and Shy-Drager syndrome. House complains to Cuddy that Charles is refusing treatment. She lets House know that Charles has called a press conference. He asked her to be there to confirm the diagnosis and prognosis.
Cameron is offering Charles comfort when House barges into the room. Promising Charles third world treatment, he takes his cell phone, throws it down the toilet, turns off the TV and throws everything on the floor. He yells at Charles that he can't ask to be treated like a villager and then call for a public press conference.
Charles later speaks to the press from his bed as House and Wilson watch from another room. House notices that Charles doesn't seem right. His internal heating and ventilation should be off, which means he can't produce sweat. With the heat in the room cranked way up and under the glare of the news lights, Charles should be bright red. But he isn't and he is sweating like crazy.
House marches into the press conference. He notices that Charles is disoriented. His heart fails and Cameron tries to shock him back. House yells into one of the cameras that this isn't TB. Later, House spells it out for Charles. He has low sugar in his cerebrospinal fluid, a classic finding of TB. But his heart failed under heat and stress, which isn't TB. They have about a dozen symptoms on the diagnosis board. House tells Charles that unless they know which ones come from TB and which ones don't, they can't treat him. House offers Charles the TB meds, but he still refuses to take them. If Charles doesn't take them, House will let him die. Then House will call his own press conference and announce that he didn't die of TB. Charles's sponsors will have to find another disease.
Charles begins the regimen of TB pills and tests. Gradually, the team begins crossing off symptoms. The team is left with P-R variability, syncope, headaches and low CSF sugar, which is from the TB that they just cured. So what else causes this low sugar? High insulin levels, for one. House suggests a very tiny tumor and, more precisely, a nesidioblastoma, which is an abnormal growth of the insulin secreting cells in one's pancreas. This causes only intermittent secretion of insulin, usually in response to stress.
House and the team take Charles into surgery. They're going to poke around where they think the tumor is and see what happens. They will inject calcium into the pancreas, which will cause the beta cells to release insulin. If there are too many beta cells because of a tumor, Charles' blood sugar will drop precipitously. This is exactly what happens. Surgery is scheduled to remove the tumor.
In his room days later, Charles is packing up his stuff. Cameron hands him a six month supply of meds. He asks her to come to Africa with the refill, but she refuses because she is interested in House. As Charles leaves, he is engulfed by a media swarm. House points out to Wilson that since he saved Charles' life, by default, he should get credit for every poor child Charles saves from here on out.