What medical specialty did House M.D. identify Gregory House as practicing?

House M.D. identifies Gregory House as a specialist in diagnostic medicine. He leads the hospital’s Department of Diagnostic Medicine, where his team investigates unusual or unexplained illnesses.

Diagnostic medicine is portrayed in the series as a process of solving complex cases by combining symptoms, test results, medical history, and specialist knowledge. House’s team often considers rare diseases after more common explanations fail, although the show dramatizes and compresses real clinical practice for television.

House is also described as having specialties in infectious disease and nephrology. These fields explain why he is especially knowledgeable about infections and kidney-related conditions, but they are not the name of the department he heads in the series.

A common mix-up is to answer infectious disease because House is repeatedly shown consulting on infections. The broader and canonical description of his hospital role is diagnostic medicine.