Tuesday February 21, 10:17 PM
Rise in number of fungal infections among contact lens users
SINGAPORE : There has been a rise in the number of fungal infections of the eye among contact lens users.
A total of 39 cases were detected, up from the 22 reported previously.
The Health Ministry has also strongly urged those using Bausch and Lomb's ReNu multipurpose solution to stop, until investigations are complete.
Bausch and Lomb's ReNu solution has a strong association with the fungal infection cases, says the Health Ministry.
A total of 35 out of the 39 contact lens wearers infected with the Fusarium solari fungus said they had used the solution.
Four were unsure of the brand they use while at least one use a different brand.
A majority of the 39 cases started developing infection in the second half of last year. Most of those infected were teenagers and young adults, aged between 15 to 24 years old.
The Ministry says that it is currently looking at a spectrum of factors in its investigations, including the solution itself and the makeup of the fungus.
It is also looking into the hygiene habits of the contact lens users.
The Ministry says that it is also collaborating with its counterparts in other countries such as Hong Kong to see if there's been a spike in the number of fungal infections there.
Dr Balaji Sadasivan, Senior Minister of State for Health, said: "In other words although there is an association, it does not mean that the solution contains the fungus.
"The solution may be perfectly alright but somewhere between the solution and its use, there are many factors that come into play. That is why we are carrying out investigations.
"It could be that the fungus has undergone a mutation that enables it to grow selectively in a particular medium that's found in this solution.
"So it may not be the solution in its original form to allow this fungus to grow but that the fungus has changed its characteristics so that while there is an association which is very strong, we have no information to explain the mechanism that has given rise to these infections."
Eye doctors say that the situation is worrying as fungal infections among contact lens users is uncommon.
It is also more difficult to treat, although the fungus itself is not contagious.
Dr Chan Wing Kwong, Head of Refractive Surgery Service at the Singapore National Eye Centre, said: "The reason that we are worried is that fungus is slow to present. In fact due to the biology of the fungi, they grow quite easily in the eye without causing too many symptoms and sometimes it can be days or weeks later before they start to present.
"They will start to present similarly with redness and pain and poor vision but they will present late and therefore the loci of the infection are now bigger.
"Because they present late, they have time to establish a foothold in the cornea and sometimes they threaten the integrity of the cornea and the cornea may get thin or perforate and that's why in the end three or four of some of these patients also has to undergo corneal transplant."
Dr Chan adds that treatment of fungal infection is also more difficult as anti-fungal agents are limited.
The 39 cases were traced from July last year when hospitals started to see a spike in fungal infections with about five cases per month, up from just one a month.
The largest number of cases reported was in January this year, with 10 cases.
Investigations are expected to take weeks, even months.
Doctors say that this is because fungus takes longer to culture as compared to bacteria which takes about 24 to grow.
Dr Balaji added: "The purpose of this press conference is because it is an issue of public safety. Once we know an association, then we have to tell the public that there is an association and tell the public to stop this product until investigations are complete.
"The investigations itself is like detective work. If you watch CSI, you know that you won't immediately have the answer but you have to have an open mind, we will investigate using technology and trying to piece things together."
Bausch and Lomb, which has suspended sales of ReNu, has about 40 percent of the market share in Singapore.
The company says that it will pick up the medical tabs of patients if its solution is indeed found to be the cause of the infections.
It will advise ReNu users what to do with the products that they have bought within the next few days. - CNA/dehttp://sg.news.yahoo.com/060221/5/singapore194315.html