What Is Hypopyon and How Can It Be Treated?

The accumulation of white or yellowish fluid in the front part of the eye (anterior chamber) may be a hypopyon. It indicates severe intraocular inflammation that requires urgent medical care.

Several conditions can cause hypopyon, some of which are life-threatening or vision-threatening. If you suspect a hypopyon, seek emergency medical treatment immediately.

What Is Hypopyon?

Hypopyon is an uncommon medical condition that occurs when white blood cells (leukocytes) accumulate in the eye’s anterior chamber. 

What Does a Hypopyon Look Like?

A hypopyon is often visible without magnification. It appears as white or yellow sediment in the front part of the eye.

What Are the Symptoms of a Hypopyon?

The most noticeable sign of a hypopyon is the presence of pus or whitish fluid in the lower anterior chamber of the eye. This is the front part of your eye below the colored area (iris).

Other hypopyon symptoms vary depending on the underlying cause of ocular inflammation. Symptoms may include:

• Blurred vision
• Redness
• Eye pain
• Eyelid swelling
• Excess tearing
• Sensitivity to light

What Causes Hypopyon?

Hypopyon is caused by severe intraocular inflammation.¹ There are many possible causes, some of which are considered medical emergencies.

Causes may include:

1. Endophthalmitis

Endophthalmitis is a medical emergency involving infection of the eye’s fluids or tissues. It requires an urgent ophthalmology evaluation.

Without treatment, endophthalmitis can cause permanent blindness. Hypopyon formation is present in about 85% of cases of acute endophthalmitis.¹  

2. Behçet’s Disease

Also called Behçet’s syndrome, this rare disease causes inflammation in the blood vessels and tissues all over the body. It can lead to serious and life-threatening problems, such as vision loss and stroke.

Behçet’s disease is a risk factor for hypopyon. Symptoms include:

• Eye pain and redness
• Blurry vision 
• Headaches
• Genital and mouth ulcers
• Joint pain and swelling (arthritis)

3. Infectious Corneal Ulcer

A corneal ulcer is an open wound or lesion on the cornea, which is the transparent dome at the front of the eye. Infections are the most common cause of corneal ulcers, with bacteria responsible for most cases.⁸

A corneal ulcer begins as keratitis, which is inflammation of the cornea. Common types of keratitis that can cause a corneal ulcer include:

• Bacterial keratitis
• Fungal keratitis
• Herpes simplex viral keratitis

Corneal ulcer complications can include corneal perforation and scarring, glaucoma development, and vision loss. 

4. Uveitis

Uveitis is inflammation of the middle layer of the eye (uvea), which is located between the retina and cornea. The uvea consists of the iris, ciliary body, and choroid.

Hypopyon is relatively uncommon in patients with uveitis. It’s most likely to occur in cases of acute anterior uveitis, especially in patients who test positive for the HLA-B27 protein.²

Anterior uveitis, also called iritis, is the most common form of the disease. Acute anterior uveitis occurs quickly and can cause severe eye pain, light sensitivity, and blurry vision.

5. Leukemia

Rarely, a hypopyon can be an early sign of a leukemia relapse. The presence of a blood-stained hypopyon warrants a prompt oncology evaluation.⁴

When Should You See a Doctor for Hypopyon?

Getting an ophthalmology exam as soon as you suspect you might have a hypopyon is crucial. Even though hypopyon is typically visible without magnification, your eye doctor will perform a slit-lamp exam or order lab work to determine the underlying cause.

How Is Hypopyon Treated?

Hypopyon treatment focuses on addressing the underlying condition causing inflammation. An ophthalmology consultation will confirm a diagnosis.

Depending on the cause, treatment for hypopyon may include:

• Intravitreal antibiotics. An injection of medicine into the gel inside the eye (vitreous)
• Surgical intervention. Pars plana vitrectomy (PPV) is a surgery to remove the vitreous from the eye 
• Intensive topical steroids and antibiotics. To reduce inflammation and fight infection after surgery
• Oral antibiotics. To fight infection in the whole body
• Topical atropine. Dilating eye drops to reduce ciliary spasms

Is Immediate Treatment Necessary for Hypopyon?

Yes. Some conditions that cause hypopyon can lead to permanent vision loss or death. Get an emergency ophthalmology evaluation right away.

Can Hypopyon Recur After Treatment?

Effective treatment of the underlying condition is typically adequate to resolve hypopyon and improve vision. However, follow-up ophthalmology exams may be necessary to monitor the eye. 

What Are the Risk Factors for Hypopyon?

Hypopyon is due to an underlying medical condition or eye infection. Risk factors for hypopyon include:²

• Behçet’s disease
• Presence of human leukocyte antigen (HLA)-B27 in the blood
• Spondyloarthropathy (arthritis of the spine)

Is Hypopyon Always Infectious in Nature?

No. Hypopyon can occur due to a wide range of conditions, including infectious and non-infectious ocular and systemic diseases. It is not contagious, meaning it can’t spread from person to person.

Endophthalmitis is a serious eye infection commonly associated with hypopyon. If left untreated, it can lead to blindness. Non-infectious causes of hypopyon include Behçet’s disease and certain types of arthritis.

How Can One Differentiate Between Infective and Noninfective Hypopyon?

You should not try to self-diagnose hypopyon or the underlying cause. Seek an immediate ophthalmology evaluation.

Summary

Hypopyon is the accumulation of white blood cells in the eye’s anterior chamber. It’s a sign of severe inflammation due to an eye infection or other condition.

Some causes of hypopyon are considered medical emergencies because they can potentially lead to blindness or death. If you notice signs of hypopyon, seek treatment right away.