Fungal Eye Infection: Types, Causes, Symptoms, Treatment

While fungal eye infections are extremely rare, they can happen to anyone. They may result from a minor poke in the eye by a branch or similar object. If not treated effectively, fungal infections can threaten vision. It's very important to know the potential signs and seek help.

Different types of fungi can cause eye infections, and it's important to distinguish which one is responsible for your infection in order to treat it properly.

This article will discuss the causes, types, and symptoms of fungal infections, treatments, preventive measures, and more.

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Fungal Eye Infection Causes

Many fungi, such as Fusarium, tend to live in soil and on plants outdoors, while the common fungus Aspergillus can be found both outdoors and indoors.

Some fungi reside in the human body. Candida (a yeast) can live on the skin or on mucous membranes that line the inside of the body and are meant to protect it.

Some people have a higher risk of developing fungal infections, including those of the eye. They include people with diabetes, those who have a weakened immune system, and people who are prescribed corticosteroids.

Types of Fungal Eye Infections

A fungal infection can occur in different areas of the eye. Those located in the front layer of the eye are known as keratitis. This clear area is the cornea. If it affects the deeper layers of the cornea, a scar can form that may affect vision.

A fungal infection that occurs inside of the eye is known as endophthalmitis. An endophthalmitis infection can impact the gel behind the lens of the eye (known as the vitreous) or the clear fluid between the lens and the cornea, known as the aqueous humor.

The two types of endophthalmitis are:

Exogenous: Fungal spores come from an external source and get into the eye.
Endogenous: The fungal infection comes from elsewhere in the body via the bloodstream. A candidemia infection in the bloodstream may spread to the eyes.

Fungal Eye Infections Symptoms

An infection can develop after even a minor injury to your eye, such as debris flying into it or an accidental fingernail scratch. It may take anywhere from just a couple of days to several weeks to become apparent.

Even if you've only had a minor trauma, you should watch for:

While these symptoms don't necessarily mean you have a fungal infection, you should take them seriously. Although fungal infections are not the usual cause, they can threaten vision when they occur. Contact an eye doctor promptly if you experience any of these symptoms.

Diagnosis

To determine if you have a fungal eye infection, the eye care practitioner examining the eye, such as an ophthalmologist or optometrist, will gently take a small sample from the infected area and send it to a lab to be tested. In trying to detect the organism, the laboratory may use the following approaches:

Culturing the specimen: The organism is allowed to multiply under controlled conditions and can then be identified. This is considered the cornerstone for identifying fungal eye infections.
Examining under a microscope: It may be possible to identify the fungus by viewing a sample under the microscope.
Polymerase chain reaction: This is testing to identify the genetic material of an infection.

Treatment

If you are diagnosed with a fungal eye infection, your eye doctor will then promptly begin treatment. The kind of antifungal treatment prescribed will depend on where in the eye the infection is, how severe it is, and the type of fungus involved.

For fungal ulcers on the surface of the eye, Natacyn (natamycin) drops may be prescribed to treat certain forms of fungi, such as Aspergillus and Fusarium.

If the infection is deeper in the eye, the ophthalmologist or optometrist may need to prescribe an oral medication, one that's injected into the eye, or a solution that's given intravenously (IV, within a vein).

Medications like the following may be prescribed:

Abelcet or Ambisome (amphotericin B)
Diflucan (fluconazole)
Vfend (voriconazole)

Sometimes, for very deep fungal infections, a two-pronged approach may be taken by combining a couple of these medications.

Unfortunately, medications don't always work. In fact, they may fail 15%–36% of the time. If this happens, surgery may be needed. In such cases, a corneal transplant may be called for.

Other surgical procedures that include what's known as a vitrectomy, in which the gel inside the eye is removed, or, in extreme instances, an enucleation must be done, which is removal of the eye.

Prevention

Because fungal eye infections can become serious, avoid them as much as possible. Here are some situations in which you may become exposed to fungi and preventive measures you can take:

Being out in nature: Fungi thrive outdoors and can be on twigs and branches that may injure the surface of the eye. Wear protective eyewear—even sunglasses can provide some protection. If you work out in nature with plants, protective eyewear is a must.
Eye surgery: Surgery, such as cataract removal, can cause germs to enter the eye. The surgeon will give you some preventive drops, which you should use, but report any signs of infection immediately.
Using contact lenses that haven't been properly sterilized: When you use your contact lenses, make sure you follow all of the proper sterilization precautions. Also, remove contact lenses before swimming, showering, or using a hot tub to avoid eye infections.
Chronic eye surface issues: Conditions such as dry eye syndrome may allow entry of fungi into the eye through damaged areas. Be aware of such issues and immediately contact an eye doctor at the first sign of any kind of infection.
Eye product contamination: Any kind of eye product, even a medical one, may be contaminated with fungi if they have been in contact with the air or surfaces that could contaminate them. Be sure to watch for product recalls and dispose of any outdated products or those that may have been contaminated.

Having a bloodstream fungal infection: These infections can result in a fungal eye infection, so that is one reason to have them treated effectively.

Summary

Fungal infections can come from outside sources, such as vegetation that may brush against the eye. But fungi can also be found inside the home and may even come from elsewhere within the human body. Symptoms include pain, redness, excessive tearing, blurriness, and eye discharge.

If you have a fungal eye infection, your eye doctor will prescribe drops to try and treat it. However, this is not always effective, and in some cases, surgery may be needed. This may involve a corneal transplant, and in severe, nonresponsive cases, eye removal may become necessary.

A Word From Verywell

If you suspect you have a fungal eye infection, don't hesitate to contact an eye care professional for a prompt assessment. The sooner it is effectively treated, the better. Fungal infections often can be cured, but the risk they pose should not be underestimated.

Frequently Asked Questions

No. They are not spread from person to person the way many infections are. Rather, you can get a fungal infection from coming in contact with something contaminated with fungi after there has been an injury or trauma to the eye.
It depends on the infection. But in severe cases treatment could be needed for months. Even then, it might not work and surgery may become necessary.
A fungal eye infection is not something that you want to leave to clear up on its own. These infections can be severe and threaten your vision. It's important to seek treatment for any suspected fungal eye infection right away.

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