Definition of AK

AK: 1. Above the knee.
2. Acanthamoeba keratitis.
3. Actinic keratosis.

Definition of Acanthamoeba keratitis

Acanthamoeba keratitis: Infection of the cornea by acanthamoeba, a microscopic water-borne ameba. The disease tends to occur in people who wear contact lens. It can accompany a bacterial infection of the eye. Acanthamoeba keratitis can produce corneal ulceration and result in severe loss of vision and even blindness. Signs and symptoms are persistent redness and pain in the eye. Treatment is with multiple antibiotics, often including antifungal drugs, and sometimes surgery after the infection has subsided.

Definition of Acanthamoeba

Acanthamoeba: A microscopic organism, an amoeba, found in soil, dust and fresh water (lakes, rivers, hot springs and hot tubs). Acanthamoeba also occur in brackish water and sea water as well as in heating, venting, and air conditioner units, humidifiers, and dialysis units.

Acanthamoeba can enter the skin through a cut, wound, or through the nostrils and, once inside the body, can travel to the lungs and through the bloodstream to other parts of the body, especially to the central nervous system (the brain and spinal cord). Through improper storage, handling, and disinfection of contact lenses, Acanthamoeba can enter the eye and there cause infection.

A particularly dire infection caused by Acanthamoeba called granulomatous amebic encephalitis is
characterized by headache, stiff neck, nausea, vomiting, confusion, loss of balance, seizures, and coma that can progress over several weeks and end in death. Acanthamoeba infections occur more frequently in people with compromised immune systems and the chronically ill. Eye and skin infections are generally treatable while infections of the brain are almost always fatal.