My Patient Complains of Redness and Photophobia After Sleeping With Contact Lenses. The Exam Shows Diffuse Patchy Epithelial and Anterior Stromal Infiltrates. What Should I Do?
White-gray corneal infiltrates are a common complication associated with contact lens wear. Although infectious keratitis is a very serious problem, contact lens-associated sterile corneal infiltrates are a more common finding. Initially, it is difficult to clinically differentiate between the infiltrates associated with a noninfectious and infectious keratitis. The infiltrates appear as single or multiple white to white-gray lesions, and they are located in the subepithelial region of the cornea. They are commonly associated with surrounding edema and inflammation. Conjunctival injection is also a common finding. The patient typically experiences pain and photophobia.
This case scenario is not uncommon. Our young patient wore her lenses overnight and now has a corneal infiltrate, conjunctival hyperemia, and discomfort (Figure 36-1). It is significant to note that she was presumably healthy up to this point, but the clinician must specifically ask the patient about her general health and ocular history. Also, on slit-lamp examination, the corneal epithelium was intact. It would be important to ask whether the patient awoke with pain or whether her pain was associated with some later event, such as attempted contact lens hydration, lens removal, or replacement.
Figure 36-1. The patient slept in her contact lenses and now has a corneal infiltrate, hyperemic conjunctiva, and pain.
Because the patient experienced the pain upon waking with the contact lenses in her eyes, and because the corneal epithelium was intact, it was much more likely that this is a case of noninfectious keratitis. This type of clinical presentation results from inflammation and corneal edema secondary to hypoxia, which is also occasionally associated with “tight-lens” syndrome.1 Therefore, initially, I do not typically scrape and culture these corneas. I commonly treat these cases with preservative-free artificial tears and a mild steroid, such as fluorometholone or loteprednol 2 to 4 times daily for 3 to 7 days. However, because of the ever-present risk that this could be the result of an infectious etiology, it is quite reasonable to add an epithelium-friendly, broad-spectrum antibiotic such as a topical later-generation fluoroquinolone. The patient must understand that she is required to contact the clinician if her symptoms worsen, and she should be seen in 1 or 2 days after the initiation of treatment. Although her signs and symptoms may not have completely resolved in 1 or 2 days, they should be improved. If not, the steroids must be stopped, and the area of the infiltrates must be cultured. I will also begin fortified vancomycin (50 mg/mL) and tobramycin (15 mg/mL). Some clinicians also culture the contact lenses and the contact lens case, but many contact lens cases are contaminated by organisms that are not the same organisms found in corneal cultures.2 Any history of possible ocular herpes virus infection should be investigated. If there is any history of swimming with soft contact lenses in place, we will also get cultures for acanthamoeba and perform confocal microscopy. However, I believe that this is somewhat unique and regional.
If the patient had noted that the pain did not begin until she attempted to hydrate the lens, remove the lens, or replace the lens, then I would consider either a toxic reaction from use of an incorrect eye drop or solution or incomplete rinsing of the lenses. The reaction to toxic substances in the eye or a hypersensitivity reaction can result in corneal infiltrates, a nummular keratitis, and possibly corneal edema but there is frequently an area of punctate epithethelial keratopathy (PEK) present, which this patient did not exhibit.3
Mechanical trauma associated with the removal of a dry lens that was left on the eye overnight or scratching the ocular surface during lens removal can cause eye pain, but slit-lamp examination would reveal corneal or conjunctival epithelial defects, which are not typically associated with an infiltrate, after just 1 night.
There are exceptions to these general guidelines, but the clinician can use the history and examination to form a revised differential diagnosis list and treatment plan. For example, did the patient come into contact with someone who had an adenovirus conjunctivitis (“pink eye”), and does she have conjunctival follicles and a pre-auricular node?
If the superior limbus and superior bulbar conjunctiva are the predominantly affected sites, then a diagnosis of contact lens-related superior limbal keratoconjunctivitis (SLK) could be entertained. Unlike the more common SLK, contact lens-related SLK is not associated with thyroid abnormalities, but it can result in pain, photophobia, and possible PEK.
Have these symptoms been present longer than a day? If so, an infectious keratitis would be more strongly considered in the differential diagnosis list. Is there a purulent discharge and epithelial defect, which is commonly associated with a bacterial keratitis? Despite the absence of a purulent discharge, a bacterial keratitis should always be considered. Antibiotic therapy should be tailored to your region, with coverage of Pseudomonas, which is a very common contact lens-related pathogen, and combined with close follow-up examinations.4
Does the patient swim with her contact lenses in place, or does she use tap water to soak her soft contact lenses? Is the patient’s pain greater than expected considering the corneal appearance, and is there a fine stippling of the corneal epithelium (Figure 36-2)? These are early signs of an amoebic keratitis, which we examine by confocal microscopy (Figure 36-3), culture, and by removal of the entire area of affected epithelium in an attempt to eliminate as many organisms as possible. We start anti-amoebic therapy then. Other findings such as ring infiltrates and neurokeratitis are later ocular findings associated with an amoebic keratitis.
Figure 36-2. This patient swims in lakes with her contact lenses in place. In this eye with early acanthamoeba keratitis, a patchy, stippled corneal epithelium is seen with a faint infiltrate adjacent to a corneal nerve.
Figure 36-3. This confocal photomicrograph demonstrates an acanthamoeba cyst within the corneal stroma (arrowhead). The size is approximately 45 μm in diameter.
Are there satellite lesions (white spots) associated with the infiltrate, which may portend the presence of a fungal keratitis? We will also perform confocal microscopy if a fungal keratitis is suspected. The use of a specific contact lens solution was recently associated with an increase in fungal keratitis. The solution was removed from the market, but some patients had purchased a large supply of the solution and continued to use it after the recall. This illustrates the importance of constantly keeping current by reviewing the ophthalmic literature and participating in ophthalmic forums.
Contact lens type; lens care; the number of hours of contact lens wear per day; and the presence of dry eyes, blepharitis, and other ocular conditions can also increase the risk of contact lens-associated keratitis. As always, a good history and examination will help to narrow the differential diagnosis list and guide treatment.
1. Kaufman SC, Dabezies OH, Klyce SD, et al. Corneal changes from contact lenses. In: Kaufman HE, Barron BA, McDonald MB, Kaufman SC, eds. Companion Handbook to the Cornea. 3rd ed. Boston, MA: Butterworth-Heinemann; 2000:661-680.
2. Krachmer JH, Purcell JJ Jr. Bacterial corneal ulcers in cosmetic soft contact lens wearers. Arch Ophthalmol. 1978;96(1):57-61.
3. Morgan JF. Complications associated with contact lens solutions. Ophthalmology. 1979;86(6):1107-1119.
4. Dart JK, Stapleton F, Minassian D. Contact lenses and other risk factors in microbial keratitis. Lancet. 1991;338 (8768):650-653.