- Kaposi’s sarcoma
- A reddish brown malignant tumor that usually begins in the skin and is most common in patients with HIV. It has been linked to infection with a newly recognized virus, human herpes virus type 8.
- Keratitis
- An inflammation of the cornea.
- Keratoconjunctivitis
- An infection of the eye surfaces that leads to inflammation of the conjunctiva, as well as the cornea of the eye, often caused by an adenovirus.
- Keratoconus
- The coning (formation of a cone-shape) of the cornea, distorting vision and found mainly in young adult males, which often leads to corneal transplants later in life.
- Klebsiella
- A major species of the bacteria genus Enterobacteriaceae, the frequent cause of such nosocomial infections as pneumonia and other respiratory diseases, as well as wound infections.
- Kluyvera
- Of the bacteria genus Enterobacteriaceae, associated with unusual wound infections often occurring in diabetics.
- Koch’s postulates
- The criteria used to determine whether a microbe is the cause of a particular infection.
- Koplik’s spots
- Red spots with bluish centers that appear on the oral mucosa in the early stages of measles.
- Kuru
- A slow virus infection of the brain related to various “mad cow” diseases, but contracted through human cannibalism.