Hugh Laurie auditioned for the role as Dr. Gregory House in his hotel room bathroom in Namibia. He was rehearsing his role for the film The Flight of the Phoenix and claimed that the bathroom was the only place with enough light. He also apologized for his appearance on tape before the audition as he'd just come back from filming. The fact that House has a somewhat scruffy and unkempt look, particularly his constant five o'clock shadow, has been attributed by creator David Shore to Laurie's appearance in this audition tape.
The diagnosis of Lupus appears to be a running joke throughout the series - it is commonly suggested as a possible illness, but is always dismissed. In one episode, House hides his Vicodin in a book on Lupus, stating that 'it is never Lupus'. In another episode House has a janitor stand in for his three assistants (who left at the end of season 3). The janitor suggests Lupus as a possible diagnosis - inevitably he is wrong.
The character of House is based on Sherlock Holmes. Both suffered drug addictions (House - pain killers, Holmes - cocaine). Both focus on the patient/criminal's motives and actions rather than physical evidence. Neither can cope with normal society and have sociable sidekicks (Wilson and Watson - Dr. Wilson actually gets called Dr. Watson once by a patient in the first series). Both are extremely lazy when not on a case (Holmes read the agony aunt columns in the paper, House watches Soaps). Both never call anybody by their first names and finally both live at No 221B.
This episode contains another reference to Sherlock Holmes. Wilson tells the (fictional) story of who had sent House a present. Wilson says it was one of House's first patients called Irena Adler. He then explains that House had feelings for the patient, but did not take it any further and therefore regards her as the 'woman who got away'. Irene Adler was an adversary who bettered Sherlock Holmes - the woman who got away. As it happens, the fist patient House treats in the pilot episode is called Rebecca Adler.
On the TV after House finishes watching his soap, its credits are rolling. Most are made-up names but two are in-joke references to staff members. Marcy Kaplan as Hair Stylist - usually credited as Marcy G. Kaplan, she was an Associate Producer for that episode and is now a Co-Producer. And Cindy Carr as Wardrobe - she was a Set Decorator for the entire first season except for the Pilot.