What medical specialty does House primarily lead in House M.D.?

House primarily leads the diagnostic medicine department in House M.D.

The department handles patients whose illnesses remain unexplained after ordinary testing or treatment. House and his fellows develop differential diagnoses, order targeted tests, and revise their theories as new evidence appears. This structure gives the series its distinctive medical-mystery format.

House is also described as having specialties in infectious disease and nephrology. Those qualifications explain his expertise with unusual infections, kidney disorders, and complex systemic illnesses. However, his position at Princeton-Plainsboro is head of diagnostic medicine, not head of either of those specialty departments.

The show’s diagnostic process is dramatized for television. Teams often pursue several competing explanations and sometimes use risky procedures when the patient’s condition deteriorates. Real hospitals do have diagnostic medicine specialists, but the speed, authority, and scope shown in the series are highly fictionalized. The department’s name is therefore more precise than simply calling House a general practitioner.