Acanthamoeba keratitis associated with cosmetic contact lens wear

THE NEW ZEALAND MEDICAL JOURNAL Journal of the New Zealand Medical Association

Acanthamoeba keratitis associated with cosmetic contact lens wear Nathan M Kerr, Sue Ormonde Cosmetic, or novelty, contact lenses are soft hydrogel lenses worn solely to change the colour or appearance of the eye. The popularity of these lenses is increasing worldwide, particularly amongst teenage adolescents.1 Although possessing no optical power, these lenses pose the same physiological impact on the eye and carry the same risks as vision-correcting contact lenses. Reported complications from cosmetic contact lenses include contact lens overwear syndrome, tight lens syndrome, corneal abrasions, Pseudomonas aeruginosa keratitis causing vision loss requiring corneal grafting, and presumed herpes simplex keratitis resulting in corneal scarring and legal blindness.2 We present the first reported case in New Zealand of Acanthamoeba keratitis, a rare and potentially blinding infection, resulting from the use of cosmetic contact lenses.

Case report A 19-year-old Māori woman was referred with a red and painful right eye after wearing coloured cosmetic contact lenses that she had purchased from a flea market. She did not receive any information at the time of purchase—and being unaware of proper lens hygiene, regularly cleaned and stored the lenses in tap water. On examination her unaided visual acuity was 6/18 in the right eye and 6/6 in the left eye. Slit-lamp biomicroscopy of the right eye showed conjunctival injection, corneal epithelial irregularity, microcystic corneal oedema, and patchy anterior stromal infiltrates (Figure 1). Figure 1. Colour photograph of the right eye of a patient with Acanthamoeba keratitis resulting from cosmetic contact lens wear

NZMJ 28 November 2008, Vol 121 No 1286; ISSN 1175 8716 URL: http://www.nzma.org.nz/journal/121-1286/3375/

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Corneal scrapings revealed Acanthamoeba trophozoites and treatment was commenced with topical chlorhexidine 0.02% and propamidine isethionate 0.1%. The patient’s symptoms and keratitis responded well to treatment and at follow-up her unaided visual acuity was 6/6 in both eyes and slit-lamp biomicroscopy demonstrated faint subepithelial scars only.

Discussion This is the first reported case of Acanthamoeba keratitis resulting from the use of cosmetic contact lenses in New Zealand. Acanthamoeba is a rare cause of infection that if not diagnosed early can lead to profound ocular inflammation and visual loss. Due to the resistance of Acanthamoeba cysts to the majority of biocidal agents it is one of the most difficult ocular infections to treat.3 Up to 93% of cases occur in soft contact lens wearers. Poor hygiene practices such as rinsing or storing contact lenses in tap water are well recognised to increase the rate of infection.4 The use of tap water allows deposits of lime scale containing pathogenic Acanthamoeba species to accumulate and adhere to the lens.5 Corneal infection occurs through a contact-lens induced abrasion and is facilitated by the production of proteases.6 Only four cases of Acanthamoeba keratitis resulting from cosmetic contact lens wear have been reported in the literature (Table 1). In three of these cases the lenses were obtained from non-eye care professionals.7–9 Two patients required corneal grafting and in both cases the final visual outcome was poor.7,9 Table 1. Case reports of Acanthamoeba keratitis associated with cosmetic contact lens wear Case

Age

Sex F

Source of lens Internet

Wearing schedule Intermittent

Specific breaches in care Cleaning in tap water

Visual acuity at presentation 6/60

Corneal graft No

Final visual acuity 6/6

18

17

29

19

F

Friend

Intermittent

6/120

No

6/6

37

26

M

Intermittent

6/30

Yes

6/60

49

55

F

Flea market Unknown

Suboptimal cleaning of lenses and case Unknown

First use

Unknown

HM

Yes

PL

F-female; M-male; HM-hand movements; PL-perception of light.

In New Zealand, cosmetic contact lenses are available from a wide variety of outlets including flea markets, clothing shops, novelty stores, and through the Internet. People who purchase lenses from these outlets are less likely to receive an eye examination, lens fitting, education regarding proper lens use and care, or ongoing follow-up compared to those who see an eye care professional.1 This may result in


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unsafe practices such as wearing lenses overnight, sharing of lenses, and poor lens hygiene. The sale of cosmetic contact lenses is not restricted in New Zealand as these lenses have no optical power and are therefore not classified as medical devices under the Medicines Regulations Act 1984. However, in recognition that all contact lenses carry risks there have been regulatory changes in the United States, United Kingdom, Canada, and Australia classifying cosmetic contact lenses as medical devices and thus subjecting them to the same regulation as vision-correcting contact lenses. This case highlights the potential for ocular injury resulting from the use of cosmetic contact lenses sold without fitting, appropriate instruction, or follow-up. The inappropriate use of these lenses may result in permanent visual impairment and even blindness.2 The cost to the health system of treating cosmetic contact lens related complications is considerable. We calculate the cost of treating a relatively uncomplicated case of Acanthamoeba keratitis to be over $8000—based on several days initial inpatient admission and then outpatient follow-up for around 6 months. However, this figure rises to over $50,000 if a corneal graft is required, when the cost of initial grafting, further surgery and possible re-grafts, and lifelong follow-up is taken into account. Furthermore, corneal grafting requires the use of scarce donor corneal tissue which could otherwise be used for patients with non-contact lens related corneal disease. We describe a potentially sight-threatening infection acquired from a cosmetic contact lens sold by a non-eye care professional that could have been prevented by adequate patient education. The risks of cosmetic contact lens wear need to be communicated to the public and we strongly advocate for regulatory change restricting the sale of these lenses. Any cosmetic contact lens wearer presenting with a red or painful eye should be referred urgently to an ophthalmologist for evaluation. Author information: Nathan M. Kerr, Ophthalmology Research Fellow, Department of Ophthalmology, Faculty of Medical and Health Sciences, University of Auckland, Auckland; Sue Ormonde, Clinical Director, Department of Ophthalmology, Greenlane Clinical Centre, Auckland Corresponding author: Dr Sue Ormonde, Department of Ophthalmology, Greenlane Clinical Centre, Private Bag 92189, Auckland Mail Centre, Auckland 1142, New Zealand. Fax: +64 (0)9 6310728; email: [email protected] References: 1. 2. 3. 4. 5.

Steinemann TL, Fletcher M, Bonny AE, et al. Over-the-counter decorative contact lenses: Cosmetic or Medical Devices? A Case Series. Eye Contact Lens. 2005;31(5):194–200. Steinemann TL, Pinninti U, Szczotka LB, et al. Ocular complications associated with the use of cosmetic contact lenses from unlicensed vendors. Eye Contact Lens. 2003;29(4):196–200. Radford CF, Minassian DC, Dart JKG. Acanthamoeba keratitis in England and Wales: incidence, outcome, and risk factors. Br J Ophthalmol. 2002;86(5):536–42. Radford CF, Lehmann OJ, Dart JKG. Acanthamoeba keratitis: multicentre survey in England 1992-6. Br J Ophthalmol. 1998;82(12):1387–92. Seal D, Stapleton F, Dart J. Possible environmental sources of Acanthamoeba spp in contact lens wearers. Br J Ophthalmol. 1992;76(7):424–7.


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6. 7. 8. 9.

Khan NA. Pathogenesis of Acanthamoeba infections. Microb Pathog. 2003;34(6):277–85. Gagnon MR, Walter KA. A case of acanthamoeba keratitis as a result of a cosmetic contact lens. Eye Contact Lens. 2006;32(1):37–8. Lee JS, Hahn TW, Choi SH, et al. Acanthamoeba keratitis related to cosmetic contact lenses. Clin Experiment Ophthalmol. 2007;35(8):775–7. Snyder RW, Brenner MB, Wiley L, et al. Microbial keratitis associated with plano tinted contact lenses. CLAO Journal. 1991 Oct;17(4):252–5.


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