Towards the beginning of the episode (around 5:30 in) Dr. Cameron brings House an iced coffee when she visits him in his office. When House says to Dr. Cameron, "Do you want to bet?" he clearly sets his coffee to the right of the day planner on his desk. He then lifts up the day-planner and retrieves a $100 bill from underneath it - and the coffee is suddenly at the very front of his desk - although no one has moved it. When the camera cuts back to the previous angle, the coffee is back to the right of the day-planner again.
When Cole is sitting on the desk, the chalkboard behind him changes words between shots.
When House was questioning Irene about her mother's possible illness, Irene's hair style changed several times in-between shots.
While Irene is having a seizure in the morgue, her top goes from being unbuttoned to buttoned fully to unbuttoned once again.
Amber claims that the patient kept asking for milk because they knew subconsciously that dairy counters the effects of ergotamine poisoning. In the Bicycle Day story of Albert Hoffman discovering the psychotropic effects of LSD, he famously requested milk, but beyond that dairy is not a medical solution for ergotamine poisoning.
When digging up the body in the cemetery, they dig through the soil directly onto the coffin.
Some people believe that most jurisdictions in the U.S. require the coffin be encased in a metal or concrete vault. However, this is a widely believed myth. There are not usually laws in the United States that require a coffin to be encased in a vault. Instead, this is usually a policy of the cemetery as it will ensure the ground does not collapse in after the coffin breaks down in the soil making the area harder on grounds-keeping staff. The thin material this coffin was made from (plywood) actually points more to a natural, or green, burial which would not encase the coffin or shroud in a vault.
When most of the team is digging up the body, Amber brings them coffee. As Thirteen drinks hers she turns the cup completely sideways as if trying to get the last few drops even though she had just obtained it, revealing that it's an empty cup.
When Irena's mother is giving her the Cross necklace (at around 38mins), due to the way the chain falls, you can see that the footage has been reversed to get the effect of the ghostly necklace being placed precisely on top and merging with the real one.
When Cole decides to bless the patient, he doesn't do so in any sort of customary Mormon way. The other option is that he was quoting scripture to her (a thing Mormons don't do) and (pretty badly) misquoted 3 Nephi 19:21.
It's mentioned that Irene's mom died in Ukraine (it was still the Soviet Union back then, however) telling us that Irene is from Ukraine/Russia herself. "Irene" is the American name of the Russian/Ukrainian name Ira (pronounced "EE-rah"), short for Irina (ee-REEH-nah). Irene's mother keeps calling her "Reena." That is not a Russian or Ukrainian name nor is it short for Irina/Irene.