Contact lens can lead to fungal infections

Reported by Susan Aldridge, PhD, medical journalist

Researchers are reporting an outbreak of a fungal infection of the cornea among soft contact lens wearers in Singapore.
Keratitis, an inflammation of the cornea, is a potentially blinding infection. It is one of the most severe complications linked to the wearing of contact lenses. However, fungal keratitis is quite rare among lens wearers. But, since March 1 2005, there has been a sharp increase in keratitis cases caused by the Fusarium fungus in Singapore. Researchers at the Singapore Eye Research Institute now report on this.

They checked all cases of fungal keratitis in lens wearers between March 2005 and May 2006. The researchers collected corneal samples and patients' contact lenses, lens cases and cleaning solutions. They also did telephone interviews with the participants. During this time, 66 people were infected, which makes an annual rate of Fusarium infection of 2.35 for every 10,000 contact lens wearers. Nearly all of the patients were on soft disposable lenses and most were on ReNu cleanser. And most of them also had poor lens hygiene habits - they would wear daily contacts overnight, wear expired contacts and wear their lenses when swimming. But the researchers think these habits can't fully account for the infections.

Two thirds of the patients affected had severe, sight-threatening infection requiring hospitalization and five of them needed a corneal transplant. This is the first reported outbreak of Fusarium among contact lens wearers. More research is needed to find out the factors involved, including the role of the contact lens solutions. Meanwhile, doctors should be on the lookout for fungal infections when contact lens wearers present with keratitis.

Source
Journal of the American Medical Association 28th June 2006 Volume 295 pages 2867-2873