Thursday 13 April 2006

Soft Contact Lenses: Risk of Serious Fungal Infection

My last post about contact lens infection by contact lens solution is here and here where I thought I was infected by keratitis. Throwed my almost full bottle of Baush & Lomb's Renu and went to the near eye shop to buy a new one. I bought AMO Complete Moisture Plus produced by Advanced Medical Optics (AMO) Ireland but manufactured by AMO China (Made in China??!, hmm.. hope it will be fine.)

The U.S. Food and Drug Administration (FDA) have learned of RARE but SERIOUSeye infection in people who wear soft contact lenses. The infection is fungal keratitis, caused by the Fusarium fungus. It can cause a permanent loss of vision. Several patients with this infection have needed corneal transplants to save their vision.

According to the American Optometric Association, there are over 30 million contact lens wearers in the United States and fewer than 30 cases of fungal keratitis have been reported in the US during this recent outbreak. Still, patients with signs or symptoms of microbial keratitis should be scheduled immediately. Indications that a patient may have microbial keratitis include:

-Red and irritated eyes lasting for an unusually long period of time after lens removal
-Pain in and around the eyes especially if it progressively worsens
-Increased sensitivity to light
-Rapid onset of blurred or fuzzy vision
-Excessive tearing or discharge

From Baush & Lomb Renu's FAQ about Fusarium infection: Fusarium is a fungus commonly found throughout our everyday environment, including on our skin. It especially thrives in tropical climates. Fusarium typically enters the eye through some sort of trauma or injury to the cornea, resulting in an inflammatory reaction. The situation is generally aggressively treated with combinations of anti-fungal and anti-inflammatory medications. The earlier the treatment is commenced, the better the results will be.

From DoctorFungus.org:

Mycotic keratitis

Definition

Mycotic keratitis refers to the corneal infection caused by either filamentous fungi (moulds) or yeast. There are important epidemiological and clinical differences between these two forms. The most important risk factors related to fungal keratitis include trauma (generally with plant material), chronic ocular surface diseases, contact lens usage, surgery, corneal anesthetic abuse, and immunodeficiencies. Interestingly, fungal keratitis is a condition related to warm climates. In the southernmost states of the United States, fungal keratitis explains up to 35% of microbial keratitis cases compared with 1% in New York or Minnesota.

Prognosis and therapy

Fungal keratitis is a serious condition that requires prolonged treatment and close follow-up. Natamycin (Pimaricin) appears to be the drug of choice and amphotericin B a second alternative. Chlorhexidine has emerged as a potential inexpensive option but current data are limited. Systemic therapy with azoles, particularly fluconazole should be considered when yeasts are involved. Surgery may be necessary, depending upon the degree of damage to the eye. Interventions range from simple scraping of ulcerative lesions to superficial or lamellar keratectomy. Animal models suggest that excimer laser may have a role in the future. Anecdotal experience with liposomal preparations of amphotericin B have suggested their potential role in refractory cases.

Read More at DoctorFungus.org If the link doesn't work, just type "Keratitis" on the top search box of the site.

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...