What is CLARE?
CLARE = Contact Lens-Induced Acute Red Eye
This is a type of keratitis associated with CL wear and caused by endotoxins released by gram-negative bacteria. The eye reacts to the endotoxins with an inflammatory response in the anterior segment of the eye. (This is the part of the eye that includes the cornea, the lens, the iris and the ciliary body.)
Usually, very little time passes between having no symptoms at all and having full-fledged CLARE with intense eye pain, copious tearing, super-sensitivity to light and a seriously red eye. There are plenty of examples of patients going to bed without any symptoms as all and then being abruptly woken up later that same night by intense eye pain and all the other symptoms of CLARE.
Gram-negative bacteria from various species and genera have been found in the eyes of patients with CLARE. A few notable examples are Haemophilus influenzae, Pseudomonas spp and Serratia spp.
It is possible to have CLARE in just one eye, but if you get CLARE in one eye you should ideally remove your CL:s from both eyes anyway.
Once the CL:s are removed, the body will usually fight off CLARE without medical intervention. It can still be a good idea to contact an eye care professional to make sure the diagnosis is correct, check for possible epithelial disruption, and also receive advice about future CL use. In serious cases, antibiotics will be needed to kill the gram-negative bacteria.
It can take several weeks for CLARE to clear up properly and you shouldn’t use CL:s during that time. The use of steroids to reduce the inflammatory response is still under debate.
How can I prevent CLARE?
- Proper hygiene is important to reduce the risk of introducing gram-negative bacteria to the eye.
- A CL case can serve as a breeding ground for gram-negative bacteria.
- Most cases of CLARE are reported from patients using CL:s even during sleep. It is therefore reasonably to assume that only using CL:s when awake will decrease the risk of getting CLARE.
- While a majority of CLARE cases are associated with hydrogel CL:s, using other CL:s won’t guarantee that you never get CLARE. CLARE have for instance been reported in association with silicone elastomer CL:s and RGP CL:s.