A Tale of Two GPCs

BY BRUCE E. ONOFREY, R.PH, OD, FAAO
July 1999

This practitioner found out that GPC isn't always what meets
the eye. Share his discovery in this tale of two cases of GPC.

There they were, as big as life. Two 7'6" giants towering over my 5'7" body. Add to this the fact that they were only 14-year-old teenagers. In spite of their incredible height, they probably didn't weigh more than 120 lbs. each, a result of a disease known as Marfans syndrome. Even more remarkable was that they were identical twins. The sight of two identical giants towering over me was almost too much to bear at 7a.m., before my morning jolt of caffeine.

I found their general exam histories as identical as their appearances. Both were 4.00D myopes, wore soft, nondisposable contact lenses and felt that their vision had changed since their last exam. Their conditions were so similar, that until I took a contact lens history, I thought that I could simply examine one and apply his results to the other.

While discussing contact lens history with their mother, I heard an all-too-common story that still makes me cringe.

Dr. Onofrey: Where and when were your children last fit with contact lenses?

Mother: At the local discount store. I don't remember the doctor's name, but I think it was about 5 years ago. We get their lenses through the mail.

Dr. Onofrey: How old are their current contact lenses?

Mother: Oh, I think they're only 3 or 4 years old.

Dr. Onofrey [to self]: ONLY 3 or 4 years old! What are they, family heirlooms?!

Dr. Onofrey [to Teen #1]: How do your contact lenses feel?

Teen #1: No problem, dude.

Dr. Onofrey [to self]: That's Dr. Dude to you, son. [to Teen #2]: How do your lenses feel?

Teen #2: Kind of scratchy and itchy.

Obviously further investigation of these clones was in order. A quick flip of the lids of both teens told the whole story (Figs. 1&2). It became quite clear that all cases of GPC are not created equal. Teen #1 was asymptomatic, while #2 had problems. Same disease, different presentation. Now the dilemma -- do we treat all GPC the same?

Mechanism of the Disease

All GPC is not equal and should not be managed the same way. But how should treatment differ? What makes one case of GPC different from another? To answer this question, we must first look at the mechanism of GPC.

Most of us have been taught that GPC is a result of an allergy to contact lens proteins. This is only partially true. Coated contact lenses do trigger an initial type of allergic reaction (typical "type I" response) mediated by the mast cell. Histamine is released, resulting in hyperemia and itching.

This explanation, however, of an allergic response to contact lens proteins does not address the tissue changes seen in GPC. Tissue changes and hyperemia are a result of a T-cell mediated inflammatory response which is also triggered by the micro-trauma of a "roughened" lens rubbing against the sensitive, highly vascular, tarsal conjunctiva.

Proper Staging

The three major components of GPC staging are: 1) area, 2) hyperemia and 3) presence of mucous. Area -- The tarsal conjunctiva of the lid can be divided into three zones. GPC lesions can be noted in any of these zones, but if present in all three, the disease can be described as diffuse GPC. As an example, a sharp anterior edge on a contact lens tends to produce a well-defined band of GPC that corresponds to the irritating contact lens edge. Even a broken suture on a cataract patient can produce a very localized case of "suture barb" GPC.

Hyperemia -- The degree of tissue injection is a good measure of local inflammation. On-going irritation results in the continuous release of inflammatory mediators that produce the "angry" hyperemic response seen in grade III and IV GPC.

Mucous -- The continuous foreign body irritation produced by the irritating contact lens induces increased goblet cell activity in an attempt to coat the lens. This process produces the sticky mucous deposits seen coating the contact lens and in the folds of the hyperemic, hypertrophic, tarsal conjunctiva.

Patient Management

Teen #1 had minimal hyperemia, grade I-II diffuse lesions, no mucous and no symptoms. Although he can continue to wear contact lenses, it's time to get rid of that filthy old pair and become more responsible by keeping fresh lenses. My advice is that disposable contact lenses should be discarded according to the manufacturer's schedule. There should be no extended wear and regular use of an enzyme product. A product like Alcon's Supra Clens is convenient and should promote compliance in less motivated patients. I advised to use a drug with mast cell-inhibiting properties, including a cromolyn product (various), lodoxamide (Alomide-Alcon), olapatadine (Patanol-Alcon) or levocabastine (Livostin-CIBA Vision). Medication should be instilled twice per day, prior to contact lens insertion and after removal to avoid any accumulation of drugs or preservatives. The patient should be monitored every 3 - 4 months for the first year for exacerbation of the disease. The patient should also be monitored on his or her upkeep by checking pharmacy refill records and contact lens order records. Noncompliance with these measures should result in the discontinuation of contact lens wear.

Teen #2 is another story. When I told him that he must discontinue contact lens wear, I could tell that he was not amused. But compare this bad news to the fact that, if he follows orders, contact lens wear may again be a possibility in his future.

The key to the management of Teen #2 is to control tissue damaging inflammation. Some practitioners would advocate discontinuing lens wear until this occurs. With the new anti-inflammatory medications available, the waiting period before continuing contact lens wear can be greatly reduced.

A topical NSAID or a topical steroid are two possible approaches, but I vote for the steroid -- they are much more effective at inflammation management than NSAIDs. New agents, like loteprednol, a soft, safer steroid, can reduce the risk of adverse effects. I advocate a dosage of three times per day with weekly taper and discontinuation of use after 3 weeks. The patient should return in 1 month for re-evaluation because, even though the patient will probably experience some improvement in that time period, they will not improve enough to resume contact lens wear that soon. My goal is to bring them back when I believe that there is a good chance to present them with the words they so desperately want to hear -- you can now resume contact lens wear! Once the patient has improved to grade II or better, he may follow the plan I gave to Teen #1. This "fitting" of the treatment to the level of the disease is known as "step therapy."

Maintaining Patient Control and Fear

Patients with GPC require extra time and attention in order to continue contact lens wear. The counseling, extra visits and responsibility that you take for their continued welfare requires appropriate remuneration. Though these patients may have gotten their original contact lenses through the $39.95 special, they must be made aware that the cheap seats are now closed. Proper care costs more than inappropriate care, and your fees should reflect this common sense fact.

Dr. Onofrey, editor and author of various ophthalmic texts, practices in Albuquerque, New Mexico.