|Giant Papillary Conjunctivitis
Signs and Symptoms
Initial presentation may occur months or even years after lens wear has been initiated. The papillae in GPC can be observed on the superior tarsus and (by definition) measure 1mm in diameter. Ocular itching after lens removal, increased mucus discharge in the morning, photophobia and decreased lens tolerance are all initial symptoms. Vision can be affected either as an artifact of the deposits on the lens, due to lens displacement secondary to superior lid papillary hypertrophy, or repetitive mechanical corneal abrasion with infiltration (shield ulceration).
The GPC response has no seasonal variation. While the histamine level of tears is increased in vernal keratoconjunctivitis (VKC), it remains level in GPC. Despite this difference, VKC and GPC are pathophysiologically similar. Cytologic scrapings from the conjunctiva of patients with GPC exhibit an immunologic response containing lymphocytes, plasma cells, mast cells, eosinophils and basophils suggesting an antigen-antibody mechanism. The action of phospholipase A2 secondary to the allergic response causes the release of histamines via the degranulation of mast cells. This increases capillary permeability, produces lymphocyte circulation (T-cells, eosinophils, and monocytes) and initiates the liberation of arachidonic acid, which is a catalyst for the cyclooxygenase and lipoxygenase pathways. These pathways produce inflammatory mediators such as thromboxanes, leukotrienes and prostaglandins that cause the discomfort and formation of the papillae.
Topical mast cell stabilizers are a tested and proven modality for treating GPC. Topical mast cell stabilizers are the treatment of choice for chronic GPC. They work by stabilizing the receptors on mast cell vesicles before they can degranulate, beginning the cycle of the allergic response. VKC, atopic keratoconjunctivitis (AKC), and GPC all respond well. If the patients history is well known for GPC, a 10-day loading period preceding the onset of symptoms with a preparation like cromolyn sodium (Opticrom, Crolom), at a dosage of four to six times daily, is usually effective in stalling or preventing the initial stages of the disease. Following this, you may need to continue therapy for four to six weeks or until the end of the episode. Another mast cell stabilizer made available in recent years is lodoxamide (Alomide). Like cromolyn sodium, it is a safe drug and is used in the same manner for a wide variety of allergic conditions, at a dosage of two to four times a day. Olopatadine (Patanol) combines mast cell stabilization with antihistamine properties and may be the best therapy due to its dual role. Another advantage of Patanol is its twice daily dosing.
Mast cell stabilizers have been shown to deliver significant therapeutic impact on the GPC reaction. However, to ease chronic irritations of this type, the most effective method remains eradication of the antigen.
In recalcitrant cases, topical corticosteroids function to deliver potent, palliative mediation by reducing the inflammatory response. Topical corticosteroids reduce capillary permeability, suppress lymphocyte circulation, inhibit the degranulation of mast cells, reduce the numbers of basophils and neutrophils, and decrease the production of prostaglandins, thromboxanes and leukotrienes. GPC resistant to standard therapies may respond to topical steroids. Excellent choices of steroids for management of GPC include Vexol, Lotemax, and Alrex.
Eyelids & Eyelashes | Conjunctiva & Sclera | Cornea
Uvea | Vitreous & Retina | Optic Nerve & Brain | Oculosystemic Disease
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