Pseudomembranous conjunctivitis is a condition that causes a thin membrane to form on the surface of the eye. It can trigger symptoms like blurred vision, along with eye swelling and discharge.

“Pseudomembrane” is a medical term used to describe a plaque of fibrin and inflammatory debris that organizes on the surface of the moist conjunctiva (the mucous membrane that covers the front of the eye) where it covers the inner eyelid. It is not a true membrane; it simply looks like one.

Although conjunctivitis is very common, it only rarely leads to the formation of a pseudomembrane.

This article discusses what a pseudomembrane is, along with causes and typical symptoms of the condition.

Conjunctivitis, or pink eye, is a broad term that refers to any infection or irritation that affects the conjunctiva. The conjunctiva is a slim, transparent membrane that covers the surface of the eyes and eyelids.

In rare cases, discharge from conjunctivitis thickens to form a yellowish membrane over the conjunctiva.

Membranous conjunctivitis occurs when the membrane penetrates the uppermost layer of the conjunctiva known as the epithelium. The membrane cannot be removed without causing significant bleeding.

In contrast, a pseudomembrane sits atop the conjunctiva. It can be peeled away without causing bleeding.

Pseudomembranous conjunctivitis can affect one or both eyes. Some common symptoms include:

A pseudomembrane isn’t always visible. When it is, it can appear as a whitish-yellow film over the region of the conjunctiva that lines the inner eyelid.

The following image provides a close-up view of a pseudomembrane linked to conjunctivitis.

Conjunctivitis has many potential causes, including viruses, bacteria, and allergies. The most common causes of pseudomembranous conjunctivitis are described below.

  • Bacterial conjunctivitis: Some cases of pseudomembranous conjunctivitis have been linked to bacterial infections, including diphtheria, gonorrhea, and group A strep.
  • Epidemic keratoconjunctivitis (EKC): EKC is a highly contagious eye infection that’s caused by human adenovirus.
  • Ligneous conjunctivitis: This chronic, noninfectious condition causes an excess accumulation of fibrin, a protein linked to the growth of pseudomembranes. It’s caused by atypical tissue healing after some type of event like surgery or trauma.
  • Ocular graft-versus-host disease (GVHD): GVHD occurs when the immune system rejects a stem cell transplant. Ocular GVHD affects the eyes and can lead to pseudomembranous conjunctivitis.
  • Stevens-Johnson syndrome (SJS): SJS is a rare skin disorder that causes flu-like symptoms followed by a blistering rash on mucous membranes, including the eye. It is an emergency that requires swift medical treatment.

Although pseudomembranous conjunctivitis is rare, anyone can get it. It affects people of all ages and backgrounds.

You might be at an increased risk if you recently came into contact with someone who had a contagious form of this condition, including bacterial conjunctivitis or EKC.

In addition, you might be more likely to develop conjunctivitis symptoms if you wear contact lenses, by which infection can be transmitted.

Pseudomembranous conjunctivitis is treatable. With prompt treatment, it is unlikely to cause complications.

However, when left untreated, it can cause corneal scarring, which could permanently damage your vision.

In other cases, untreated pseudomembranous conjunctivitis causes the eyelid and the conjunctiva of the eyeball to fuse together, causing dense scarring, a condition known as symblepharon.

It could also make your eyes vulnerable to additional infections.

Treatment for pseudomembranous conjunctivitis usually involves removing the pseudomembrane with a small pair of forceps. An eye specialist will apply a local anesthetic to prevent pain during the procedure.

Other treatments address the underlying cause of conjunctivitis or help to alleviate symptoms. Some of these include:

Mild cases of conjunctivitis often resolve without treatment. But pseudomembranous conjunctivitis may be a sign of a serious infection that needs treatment to resolve.

You should see a doctor if you experience eye swelling and redness with pain, blurry vision, sensitivity to light, or the sensation that there’s something stuck in your eye.

The first step in diagnosing pseudomembranous conjunctivitis is identifying the underlying cause. A doctor will ask you about your medical history and symptoms.

To diagnose pseudomembranous conjunctivitis, your doctor will examine your eye with a slit lamp. A slit lamp is a type of microscope used to perform eye exams.

While your doctor examines you under the slit lamp, they may use a cotton swab to peel away the pseudomembrane.

Finally, your doctor might also order a culture. This requires collecting a sample of your eye discharge and sending it to a laboratory for testing.

Pseudomembranous conjunctivitis occurs when a membrane-like film forms on the surface of the eye. It is usually caused by an illness or infection that affects the conjunctiva.

Most people with conjunctivitis do not develop a pseudomembrane. But you should consult with a doctor if you think you have more than a mild case of pink eye.

A doctor will identify the cause of your conjunctivitis and address symptoms like pain and swelling. After diagnosis, they will remove the pseudomembrane to help prevent future complications.