treatment
plan
Use
Fusarium Cases to Emphasize Proper Lens Care
BY
LEO SEMES, OD, FAAO
In
the realm of microbial keratitis (MK), fungal infections are a rare occurrence.
Among corneal fungal infections, Fusarium species occupy a
minor position.
The recent publicity of a cluster of cases, however, has made us all aware of this entity.
Recognize the Condition
First, you should heed the blitz of information that has bombarded
us recently regarding recognition, risk, appearance, treatment options and outcomes
for fungal keratitis with lens wear. The ulcer is generally circular with feathery
edges and may have an immune ring. The eye may appear quieter than in bacterial
MK.
Advise your patients to wear and care for their contact lenses
as directed and to treat and replace the contact lens case monthly. This is critical
because Fusarium can reside almost anywhere, including tap water. For this
reason, advise patients to use only sterile solutions for anything that touches
the contact lens, the case and the eye.
Information for patients from the American Optometric Association
(AOA) about fungal keratitis and how to prevent it, including a reference image
of the condition, is available at www.aoa.org/x5119.xml. A comprehensive clinical
guidance specifically for clinicians is available at www.aoa.org/x5166.xml.
Instructing Patients
With apprehension and anxiety running high, reassure patients
that they will be safe when they care for their lenses properly. Emphasize that
they wear and replace their lenses based on the appropriate schedule. Instruct them
to remove and disinfect daily wear lenses overnight. Mention that the most effective
defense against microbial organisms of any sort is to rinse, rub and re-rinse the
lens before disinfection. This scheme provides the highest level of protection from
infection.
Patients at greatest risk for fungal keratitis are those who live
in warmer and more humid environments, those who don't follow instructions regarding
lens wear and care and those who are in situations where vegetative matter may be
a potential contaminant.
Treatment Options
When faced with a Fusarium infection, topical treatment
should include intensive Natacyn (natamycin 5% suspension, Alcon Laboratories) for
the first three days with continued treatment over the next seven to 14 days. An
alternative is amphotericin B (Fungizone, Bristol Myers Squibb, extemporaneously
prepared by a compounding pharmacy). Some clinicians recommend adjunctive oral anti-fungals.
Additional treatment options include lamellar keratectomy, amniotic
membrane transplant (AMT) and penetrating keratoplasty. While these may sound grim,
most patients who develop a Fusarium infection have gained improved visual
acuity following treatment.
Recommendations
What should you do if you encounter fungal keratitis? You should
first obtain corneal scrapings for culture and analysis before initiating any treatment.
You can begin empirical treatment for bacterial keratitis unless you strongly suspect
and risk factors suggest fungal keratitis. In that case, institute specific treatments
discussed above. Clinicians can report cases to local, state or federal health departments.
The CDC's resource phone number is 800-893-0485.
Take the Opportunity
This rash of Fusarium cases doesn't have to be a crisis.
We should treat it as an opportunity to remind our patients about safe contact lens
wear and care.
To obtain references, please visit
www.clspectrum.com/references.asp
and click on document #127.
Dr. Semes is an associate
professor at the University of Alabama at Birmingham School of Optometry.
Contact Lens Spectrum, Issue: June 2006