Also known as: Brain-eating amoeba infection
Foreman contracts a deadly parasitic infection (Naegleria fowleri) that enters through the nose and migrates to the brain where it feeds on brain cells. This is the central medical mystery of the episode, with Foreman going blind, experiencing severe pain, muscle contractures, and ultimately requiring emergency brain biopsy. The infection was acquired from contaminated water on a patient's roof.
Also known as: Brain-eating amoeba infection
A police officer who died from the same Naegleria infection in the previous episode. His autopsy and the source of his infection drive the investigation to save Foreman in this episode.
Also known as: Legionella infection
The deceased cop had a pre-existing Legionella pneumophila infection that paradoxically slowed the progression of his brain-eating amoeba infection by stimulating his immune system.
Foreman develops pancreatitis as a toxic side effect from the multi-drug cocktail used to treat his unknown infection, with amylase and lipase levels three times normal, causing severe abdominal pain.
Foreman experiences temporary blindness due to damage to the occipital lobe (primary visual cortex) from the amoebic infection. He exhibits Anton syndrome, believing he can still see despite being blind.
Also known as: Childhood masturbation
A young girl presenting with episodes of rocking, grunting, sweating and dystonia in her car seat. Parents mistakenly believed these were seizures, but House diagnoses it as normal childhood self-stimulation behavior.
The amoebic infection spreads to Foreman's primary motor cortex, initially causing muscle contractures in his hand. After the brain biopsy, he suffers permanent damage resulting in inability to move his left toes, suggesting lasting neurological deficit.