Blebitis and Endophthalmitis
Chat Highlights
July 15, 2009

On Wednesday, July 15, 2009, Dr. Jonathan Myers, a glaucoma specialist at Wills, and the glaucoma chat group discussed "Blebitis and Endophthalmitis".

Moderator: Welcome back Dr Myers! Thank you for being here. Our topic this evening is Blebitis and Endophthalmitis. Can you start off with telling us what a bleb is?

Dr. Jonathan Myers: The bleb is the small blister in the conjunctiva under the eyelid formed by fluid draining through the trabeculectomy.

P: What is blebitis?

Dr. Jonathan Myers: As you all probably know, trabeculectomy is the most common surgical procedure to lower eye pressure to treat glaucoma. The bleb collects fluid and absorbs it into the blood vessels. So, blebitis is infection of the bleb.

P: How is a diagnosis of blebitis made?

Dr. Jonathan Myers: The diagnosis is made when the physician notes a few key features in an eye with a bleb. First, the eye is almost always red. The redness is usually worse around the bleb. The bleb may have pus within it. The anterior chamber, the front of the eye, may have white blood cells - signs of inflammation. Often, a leak is seen in the bleb, which is thought to be the entry site for the infection.

P: Are there any other other signs?

Dr. Jonathan Myers: If the infection is particularly bad, there may be white blood cells in the back of the eye, in the vitreous. This constitutes endophthalmitis, and is much more serious.

P: How does a patient get blebitis?

Dr. Jonathan Myers: Bad luck is the number one risk factor, I think, but there are others.
First, some patients have more crusting and debris around the eye - blepharitis. Also, it seems that blebitis may be more common in patients of African descent and in the southern U.S. In addition, some blebs have particularlythin walls, which may let germs in more easily, or may leak more easily, allowing germs to get in.

P: Is age a factor?

Dr. Jonathan Myers: Age is likely a factor. Kids with functioning blebs are much more likely to get blebitis. We're not sure if that is because these kids have thinner walled blebs, poor hygiene, or other factors.

P: Does a patient who has a tube shunt have a lesser risk of getting blebitis?

Dr. Jonathan Myers: Good question. Infections are much more rarely seen in tube shunts than trabeculectomies with blebs. It seems that the bleb formed by a tube surgery, being located more deeply in the orbit, and being thicker walled, is less prone to infection.

P: Will the infection just go away on its own with time?

Dr. Jonathan Myers: These bleb infections do NOT clear on their own, and can lead to blindness quickly in the case of virulent germs.

P: How quickly does a patient need to react? Does a patient need to immediately go to the ER or would an office visit the next day be sufficient?

Dr. Jonathan Myers: These infections are true emergencies, and immediate evaluation by an eye doctor is critical. Patients with bleb infections must go directly to an ER- or doctor's office- within the hour, not later that day.

P: Can they spread to the bloodstream?

Dr. Jonathan Myers: I have not ever seen this type of infection spread to the bloodstream, although infection in the blood can go to the eye.

P: I have a bleb; what can I do to avoid blebitis?

Dr. Jonathan Myers: It is unclear what a person can do to avoid this infection, other than regular lid/face hygiene and regular evaluations by your eye doctor.
The signs and symptoms of a bleb infection are important to know: Some people recommend the mnemonic RSVP.
R is for redness of the eye.
S is for sensitivity to light
V is for change in vision
and P is for Pain or Pus.
If a person who has had glaucoma surgery has these symptoms- even just a couple- it's a good day to see the eye doctor!

P: Does the whole eye becomes red or is it mainly the bleb site that is red when blebitis is present?

Dr. Jonathan Myers: Blebitis often starts a lot like pink eye, but in just one eye. The redness may start just in the part of the eye with the bleb (usually under the upper lid) and then spread and increase in intensity.

P: Is there anything we can do if we are far away from an ER and get a bleb infection or conjunctivitis?

Dr. Jonathan Myers: If you can see any medical doctor, they can prescribe antibiotic eye drops to start. If you can't find a doc, and you don't have any access to antibiotics, the best you can do is try to find a way to get to a doctor and antibiotics. I know of no other treatment or options.

P: If diagnosed with this condition, what is the treatment?

Dr. Jonathan Myers: Blebitis may range from a mild infection easily treated with just drops, to an infection that can destroy sight in hours. Treatment always involves antibiotic eye drops, and sometimes oral or IV antibiotics. The eye drops may be given anywhere from four times a day, to every hour (even through the night) depending on severity. Typically, we give a fourth generation fluoroquinolone (a newer type of anitbiotic) such as moxifloxacin or gatifloxcin, however, fortified antibiotics such as cefazolin, gentamicin, tobramycin, or vancomycin may also be used. Oral antibiotics are helpful to increase penetration into the back of the eye, the vitreous.

P: Does this infection effect the longevity of the bleb?

Dr. Jonathan Myers: That's a good point to bring up. Yes, the infection may cause inflammation that may lead to scarring and failure of the bleb after the infection has been cleared. This is good and bad. It is bad, because a failed bleb does not lower pressure; it is good, in that a failed or scarred/thicker walled bleb is less likely to get infected. Sometimes the inflammation may lead to scarring and closure of a leak that led to the infection. If there is a leak, once the infection is cleared, it makes sense to have a surgery to close the leak. People who have a blebitis once seem to have a greater chance of having it again later if the bleb is still thin-walled.
Thin-walled blebs are more common after surgery with antimetabolites such as 5-FU and mitomycin. However, 5-FU and mitomycin increase trabeculectomy success. Surgeons do not seek thinner blebs for patients, but that is how some patients heal after surgery. Often these thinner blebs have lower pressures. In the last decade, surgeons have been slightly altering some details of how they perform trabs and apply mitomycin to help influence bleb formation to reduce very thin, leaky bleb formation.

P: If blebitis is caught early by the doctor, can endophthalmitis be averted?

Dr. Jonathan Myers: Endophthalmitis is when an infection involves the entire eye: front and back. It is very serious and can lead to loss of vision or loss of the eye. Endophthalmitis is seen after approximately one in 1,000 eye surgeries.

P: How common is blebitis?

Dr. Jonathan Myers: Blebitis has been reported to range from about one in 100 functioning blebs per year to one in 1,000. We think that in the Northern U.S. A it's closer to one per 1,000 now. But in Florida and the south, it seems to be more common.

P: Does early detection prevent endophthalmitis?

Dr. Jonathan Myers: Early detection of leaks may prevent blebitis. Early detection of blebitis and prompt treatment usually prevents endophthalmitis.
If a leak is found, some docs prescribe preventive antibiotics, some don't. The reason some docs don't is for fear of selecting the most virulent germs that may resist antibiotics.
No one knows the right answer. However, it seems that the longer you watch a leak, the more the risk of developing an infection. We can repair leaks a variety of ways.
Sometimes, the patient's own blood can be injected into the bleb as a stop leak; sometimes glue (like crazy glue) can be used; sometimes, it's best to just go to the operating room and pull some healthier, adjacent tissue over the leak and suture it closed.
Eye rubbing and trauma may lead to leaks.

P: Do you ever use injection to the site if it in an extreme condition?

Dr. Jonathan Myers: Injections of antibiotics directly into the eye are routinely used for endopthalmitis, but less commonly for blebitis.

P: How long do you watch a leak before you begin treating it in one of the ways you mentioned?

Dr. Jonathan Myers: This is a controversial question. In a patient with low risk factors for infection, and who is able to reach a doctor quickly and can understand when to come in, some doctors may watch for weeks or even months. Some leaks will close, some won't. Some that close will later re-open. Some leaks a doctor can tell just by looking at them that they have very little chance of closing on their own. If a patient has a history of a prior infection, or risk factors for infection, or cannot easily reach a doctor in an emergency, I think it's often best to just bite the bullet and close the leak. However, sometimes interventions to close leaks may lead to a less functional trab (higher pressure or the need for drops).

P: Are there other eye conditions that look like blebitis but are not?

Dr. Jonathan Myers: Pink eye, which may be viral or bacterial, can mimic blebitis. Uveitis—a sterile inflammation in the eye—can causes redness and light sensitivity and pain. Herpetic infections (a virus) can look like blebitis. Sometimes a reaction to an eye drop can also cause redness and some irritation. That's why a thorough exam is critical before the therapy is initiated.

P: What are low risk factors for infection?

Dr. Jonathan Myers: Patient's with thick walled blebs, no history of infection, minimal blepharitis (inflammation and crusting around the eye lid margins), and no other eye or general health issues have a lower risk.

P: How many patients with a trabeculectomy have blebitis at least once and does it usually occur immediately after surgery or years later?

Dr. Jonathan Myers: Most blebitis occurs years after the original surgery. The vast majority of patients do NOT EVER have even one episode in their entire life.

P: If a patient has blebitis once, what are the odds of it occurring again?

Dr. Jonathan Myers: If the blebitis occurred because of a leak or thin-walled bleb, and that issue is corrected, the patient will likely not ever have another episode. If there is a predisposing factor that is not corrected, and sometimes it's safer not to, then the odds are higher, but still the best bet is that it won't happen again.
An example of an issue not corrected: a patient with only one seeing eye has a thin-walled bleb and develops a mild blebitis. The blebitis responds quickly and easily to treatment. The patient needs a very low pressure for their advanced glaucoma. In this case it may be safer to watch and wait, rather than to intervene and risk loss of the pressure control. We intervene mostly for leaking blebs.

P: Is the pain with blebitis and endophthalmitis intermittent or constant?

Dr. Jonathan Myers: Usually, the pain is mild to start with, and then builds. It is usually fairly constant, a dull ache, but often worse with light.

P: What is blepheritis and is it common to have with blebitis?

Dr. Jonathan Myers: Blepharitis is inflammation at the edge of the eyelids. The eyelids have 50 or so oil glands at the edges, and these glands can get backed up (meibomitis) or inflamed and/or infected along the lashes (blepharitis). This condition is like dandruff of the eyelashes. It is common and annoying, but usually harmless. Typical treatment is tears, warm compresses, and gentle scrubs with a wet wash cloth, sometimes with baby shampoo. Blepharitis may lead to crusting in the morning, a feeling that something is in the eyes, a film sensation or film over the vision, itching and burning, and may wax and wane over weeks and months. Rarely, it may predispose to bleb infections.

P: What is the treatment of endophthalmitis?

Dr. Jonathan Myers: Antibiotics- drops, pills, IV, injected- are aggressively used to treat endophthalmitis. Also, sometimes, surgery is done to remove the infected vitreous (a vitrectomy).

P: How does endophthalmitis cause permanent visual impairment?

Dr. Jonathan Myers: The infection, toxins made by the germs, and the inflammation may all damage the retina in a way that has no known treatment.

Moderator: Dr do you have any closing comments about blepitis and endothalmitis? A “take home message” for us and our readers?

Dr. Jonathan Myers: Blebitis is a serious issue that requires immediate attention, and can be devastating if not treated promptly and aggressively. All patients who have had trabeculectomy should be aware of the warning signs: RSVP—Redness, Sensitivity to light, Vision Change, Pain/Pus. But remember: this is an uncommon condition; most people will NEVER get!

Moderator: No matter how long ago the surgery?

Dr. Jonathan Myers: No matter how long ago the surgery.

Dr. Jonathan Myers: Good night.

On August 5, Dr. Pro discussed "Pseudoexfoliative Glaucoma" in the Chat room. Click here for highlights of that meeting.

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