Although relatively rare, acanthamoeba keratitis is a serious infection of the cornea that can result in permanent visual impairment or loss. The condition is usually very painful and caused by a free living, microscopic amoeboid organism usually found in bodies of water such as lakes, oceans and sea water as well as swimming pools, hot tubs, steam rooms, domestic tap water and even soil and air.

The number of cases of acanthamoeba keratitis is greater in contact lens wearers due to poor hygiene practices, but it can also present in non-contact lens wearers where some kind of corneal injury or trauma may have taken place.


  • Sensation of something in the eye
  • Pain in the eye (this may be severe and out of proportion to the initial inflammation in the eye; it may also be painless in the initial stages)
  • Eye redness
  • Blurred vision
  • Sensitivity to light (photophobia)
  • Excessive tearing

It can present in both eyes.

Risk Factors:

  • Handling or storing of contact lenses incorrectly. Contact lenses should not come in to contact with water. Before handling lenses, hands should be washed with antibacterial soap and dried thoroughly with a clean, lint free cloth. The contact lens or contact lens case should NOT be rinsed in tap water.
  • Incorrect disinfection of contact lenses. If non daily disposable lenses are used, the lenses should be cleaned, disinfected and stored correctly in the recommended contact lens solution as directed by the optometrist.
  • Topping up old contact lens solution. Fresh solution should always be used to disinfect lenses after each use. Once the lenses are comfortably in the eye, the existing solution in the case should be discarded and not topped up.
  • Using old or non sterile contact lens solutions.
  • Dirty contact lens case. Where in use, the contact lens case should be rinsed with contact lens solution after the lenses have been inserted into the eyes and left to air dry upside down to avoid contamination. The lens case should be replaced regularly.


Acanthamoeba keratitis is a very serious eye disease and difficult to treat particularly as it progresses. Prevention is therefore very important. It is vital to seek advice if you feel that you are experiencing any of the above symptoms.

For further advice, call the practice on 020 7222 0066 or email us at