A case series of overnight orthokeratology-related Acanthamoeba keratitis in Northwest China: Clinical presentation, management, and outcomes

Abstract

Purpose

To report a series of overnight orthokeratology-related Acanthamoeba keratitis (OK-AK) at a teriary transfer care eye hospital in China from January 1, 2021, to February 29, 2024, and to provide a reference for its treatment.

Methods

This was a single-center, retrospective case study. Records of patients with a history of OK lens use who were diagnosed with AK were analyzed. Data on clinical presentation, management, and outcomes were analyzed. We also preliminarily investigated behaviors associated with the risk of OK-AK.

Results

A total of 11 patients were included (8 females, 3 males, 14 eyes). The mean age was 14.7 ± 3.6 years (range: 11–22 years). All patients were using OK for an average of 3.5 ± 2.4 years (range: 1–8 years) before the onset of AK. The median time from onset of symptoms to diagnosis was 5 days (range: 2–150 days). The most frequently presented symptoms were blurred vision (n=11, 100%), redness (n=8, 72.7%), and excruciating eye pain (n=8, 72.7%). Topical anti-amoebic agents (a combination of topical polyhexamethylene biguanide [PHMB], metronidazole, and voriconazole) were used in all infected eyes once the AK diagnosis was made. Systemic metronidazole and/or voriconazole were added in stromal keratitis. Eight eyes (57.1%) were cured by medication. The remaining eyes (6/14, 42.9%) underwent therapeutic keratoplasty surgery because of poor response or rapid progression of the disease. The surgeries included two lamellar keratoplasty (ALK), one deep lamellar keratoplasty (DALK), and three therapeutic penetrating keratoplasty (TPK). Recurrence occurred in two cases (2/6, 33.3%), one after 1 year following DALK and the other 3 months after TPK. All patients had improved visual acuity after treatment.

Conclusion

This findings indicate that OK-AK is a serious problem in Northwest China. AK should be suspected early in patients with OK lens use who present with clinical symptoms such as eye redness and pain. The medication cure rate in OK-AK was 57.1%. The early keratoplasty surgery rate was 42.9%, and the risk of post-operation recurrence should be a concern. Based on the above findings, clinicians need to establish a standardized follow-up system and carry out multi-dimensional user education.