In House M.D., Lisa Cuddy says Gregory House is board-certified in nephrology besides infectious disease.
Nephrology is the medical specialty concerned with the kidneys, kidney function, fluid balance, electrolytes, and related disorders. Infectious disease focuses on illnesses caused by pathogens and on complex infections. House's two certifications help explain why he can approach cases involving both organ failure and unusual infections.
The show generally presents House as a diagnostician rather than as a doctor limited to one specialty. His team draws on pathology, neurology, oncology, cardiology, immunology, and surgery when a case demands it. The nephrology detail is therefore a background credential, not a description of every diagnosis he makes.
A common mix-up is nephrology versus urology. Nephrology is primarily a medical specialty dealing with kidney disease and physiology, while urology is a surgical specialty involving the urinary tract and male reproductive system. House's stated certification is nephrology.