In the first season of House, House lived on the 4th floor of an apartment building. When Cameron comes to House's apartment, the entry is on the farthest right wall. In further seasons his apartment has a first floor external shot. The entry door is on the left wall and the layout is different. In season 5, Wilson mentions to House that he doesn't like change and has lived in the same apartment for 15 years.
When Cuddy and House meet in the hall (they talk about his birthday), Cuddy has a pearl necklace around her neck. Minutes later, when Cuddy enters the boys' bathroom to talk with House, she isn't wearing the necklace.
When House is talking to Luke about the Vitamin K deficiency and eating the hamburgers, the lid on the tomato sauce bottle is alternately open/closed between shots.
In this episode, the patient is finally diagnosed with having Wilson's Disease by Foreman's confirmation of a copper-colored ring around her cornea. This ring, called a Kayser-Fleischer Ring, actually presents itself as a gray-green color.
Wilson gives a diagnosis of cancer based on a sonogram when he should have only said the patient has a tumor. The only way to actually diagnose cancer is with a biopsy.
During both ultrasounds, when they show the organ that looks like a greyscale image of the inside of a tomato, it is presented as a large tumor. The ultrasound image is actually of a right kidney with no pathology. When Wilson performs the ultrasound-guided ethanol injection, the needle is seen going inside the kidney, not the imaginary solid mass.
After Luke confronts House about Foreman giving his mother, Lucy, Haldol to sedate her, House begins to walk away and the edge of his shoulder visibly bumps the tip of Luke's nose.
When Lucy throws up blood and the camera switches angle, you can see the hose behind her.
In the elevator at the end, you can clearly see an elbow of a sixth person, yet there are only five leaving the elevator when they get off.
At the end of the scene where House and Foreman are arguing, where house says "Lets see who's right before she bleeds to death," the other doctors walk out. The camera zooms in towards House; however, if you look at the glass wall to the right you can clearly see the reflection of the camera crew.
When the social worker comes to take Luke into custody, she identifies herself as working for "Social Services, State of New Jersey." House also refers to "Social Services, State of New Jersey" when he discovers that Lucy made the phone call. This is incorrect. In New Jersey, the department that would handle this type of case is called the Department of Youth and Family Services or DYFS (pronounced "DYE-fus"), and any representative would identify themselves as such.