Like more than 140 million other people in the world (Stapleton et al, 2007), I am a contact lens wearer; and, like up to 50% of them (Pritchard et al, 1999), I have dropped in and out of contact lens wear due to contact lens discomfort. My source of contact lens discomfort is partly dry eye-related and partly contact lens papillary conjunctivitis (CLPC)-related.
Having oscillated in and out of these conditions for many years, I once again find myself back in my spectacles trying to recover from a recurrence of CLPC. This current ocular state led me to the following questions for this month’s Research Review column: What is CLPC? And, what can we do about it?
What Is CLPC?
CLPC is characterized by papillae and hyperemia of the upper palpebral conjunctiva and can result in excessive mucus in the tear film (Skotnitsky et al, 2006). Both giant papillae (> 1.0mm in diameter) and macropapillae (0.3mm to 1.0mm in diameter) are visible with lid eversion as elevations on the palpebral conjunctiva, distinguishable by their irregular specular reflection.
To assess CLPC, various grading scales divide the palpebral conjunctiva into several areas. The Cornea and Contact Lens Research Unit (CCLRU) scale, for example, indicates that the areas most relevant to contact lens wear are 1, 2, and 3, in which area 1 is nearest the palpebral border, area 2 is the central area, and area 3 is the area along the lid margin of the palpebral plate (1996). Using the cobalt blue light of a slit lamp in conjunction with a Wratten filter can better show the size of the papillae. Skotnitsky and colleagues (2006) report that CLPC can present as local or general, based on papillae observed in one or two areas for local CLPC and in three or more areas for general.
How Often Does It Happen?
CLPC is more common than both practitioners and patients would like to think. In a study of 205 contact lens wearers who wore lotrafilcon A silicone hydrogel contact lenses for 30 days of continuous wear over a 12-month follow-up period, 25% of participants experienced CLPC (Tagliaferri et al, 2014). This is in line with other reports, indicating an incidence ranging between 1.5% to 47.5%. (www.siliconehydrogels.org/editorials/feb_07.asp ).
Unlike other adverse events in contact lens wear such as corneal infiltrates and corneal erosions, CLPC rarely occurs in the first few months of lens wear; more events occur thereafter, with increasing incidence over time (Sankaridurg et al, 1999).
What Does CLPC Mean for Contact Lens Wearers?
CLPC can lead to increased lens movement and awareness, itching, and mucous discharge. Unmanaged, CLPC can result in contact lens intolerance and eventual contact lens dropout (Tagliaferri et al, 2014), with one study finding that CLPC accounted for nearly 50% of contact lens dropouts (Sankaridurg et al, 1999). The chronic nature of the condition and its frustrating recurrence can lead to this permanent discontinuation.
Causes
The mechanisms of CLPC are poorly understood, but they are generally attributed to one of two main factors: mechanical trauma or an immunological and inflammatory response. It has been hypothesized that local CLPC as described by Skotnitsky et al (2006) is due to mechanical causes, while generalized CLPC results from an immunological response to biodeposits on the contact lens (Skotnitsky et al, 2006).
The mechanical etiology is supported by the observation of papillae over sutures and ocular prostheses, with papillae in this case forming in the area that is in contact with the external stimulus (Jolson and Jolson, 1984). In the case of CLPC, it is thought that the constant friction of the lens against the upper palpebral conjunctiva may result in the release of inflammatory mediators, triggering the response (Stapleton et al, 2006). Mechanical factors that may contribute to this include the lens modulus of elasticity and the edge shape (Stapleton et al, 2006).
The immunological etiology is supported by the identification of basophils, eosinophils, and mast cells in the palpebral epithelium of those who have CLPC as well as an increase in leukocytes and neutrophils (Allansmith et al, 1977) and immunoglobulin E in the tear film (Ballow et al, 1989; Zhao et al, 2008), indicating an immune response to contact lens deposits, supporting both a type I and a type IV hypersensitivity response.
While contact lens bacterial bioburden has been associated with a four- to eight-fold increase in contact lens inflammatory events (Szczotka-Flynn et al, 2010), this has not been associated with CLPC (Tagliaferri et al, 2014). However, both Tagliaferri et al (2014) and Skotnitsky et al (2006) have shown a seasonal trend relating to peaks in allergens, indicating that as clinicians, we need to be aware of this seasonal relationship.
Management
The early indicators of CLPC can be easy to miss: increased mucus in the canthus and itching that increases upon lens removal. Over time, this progresses to increased lens movement, increased lens awareness, and intolerance to contact lens wear. CLPC management needs to address the acute condition as well as prevent recurrence.
Treatment of the Acute Response The first step is to eliminate the causative factor by implementing a period of contact lens discontinuation. Given the type I and IV hypersensitivity factors associated with CLPC, current treatments include mast cell stabilizers, topical nonsteroidal anti-inflammatory drugs, and topical steroids (Donshik et al, 2008). Steroids such as loteprednol etabonate 0.5% administered four times daily for up to six weeks have the dual action of inhibiting the arachidonic pathway as well as minimizing mast cell degranulation by stabilizing cell membranes (Noble and Goa, 1998). The risks of using corticosteroids are well-documented, with long-term use placing patients at increased risk of infection, elevated intraocular pressures, and cataract formation.
In a study comparing olopatadine 0.1%, fluorometholone 0.1%, or the combination of the two administered twice daily for eight weeks, the combination therapy was the most effective, followed by olopatadine (Khurana et al, 2010), although all groups were comparable in performance.
Tacrolimus 0.03% is an immunosuppressive agent that has recently been used to treat CLPC. One study compared tacrolimus 0.05%, fluorometholone 0.1%, and saline (sodium chloride 0.9%) (Diao et al, 2012). Tacrolimus did not differ in terms of efficacy from fluorometholone in treating CLPC, and the authors suggested that contact lens discontinuation in conjunction with saline rinses had similar efficacy (Diao et al, 2012).
Preventing Recurrence To prevent recurrence, the factors contributing to the mechanical and immunological mechanisms of CLPC need to be minimized. To minimize mechanical trauma, changing lens type or material to a lower modulus may help to reduce the friction between the palpebral conjunctiva and the contact lens.
To minimize the immunological response, patients need to be educated about how to clean and store their lenses and how to manage their lens case. Alternatively, changing to a more frequent replacement schedule, such as daily disposables, may help to further reduce the risk of CLPC recurrence by eliminating the buildup of biodeposits and the need for cleaning and disinfection solutions (Porazinski and Donshik, 1999). In a study of 74 neophytes randomized to wear silicone hydrogel daily disposable or no lenses for 12 months, bulbar and limbal hyperemia, corneal staining, and papillary conjunctivitis were not clinically different between the groups, with the only variable that differed being conjunctival staining (Morgan et al, 2013). This suggests that daily disposable lenses have minimal effect on ocular physiology and may be a good alternative for people who have CLPC.
A Passing Phase
After spending several weeks out of my contact lenses and changing to a daily disposable lens, I am keen to get back into my lenses. I anticipate many years ahead of spectacle-free vision. Dropping out of contact lens wear is not on my horizon! CLS
To obtain references for this article, please visit www.clspectrum.com/references and click on document #254.
Dr. Markoulli is a senior lecturer at the School of Optometry & Vision Science at the University of New South Wales in Sydney.