To present a case of infectious crystalline keratopathy after corneal cross-linking in a child with delayed wound healing, and its successful management with antibiotic and anti-fungal eye drops.
A 14-year-old male presented for a second opinion with a non-staining crystalline keratopathy after corneal crosslinking for progressive keratoconus. He reportedly rubbed his eyes vigorously in the post-operative course and had a slowly healing epithelial defect. He was treated with several antibiotic drops and was put on high dose topical difluprednate drops post-procedure for persistent corneal haze. His infection continued to progress until steroids were stopped and he was treated with topical voriconazole. While cultures were negative, the patient’s visual acuity and corneal lesions improved significantly after starting voriconazole therapy and stopping steroid drops, pointing to a diagnosis of infectious crystalline keratopathy.
Conclusions and Importance
This is one of the first case reports to describe a primary infectious crystalline keratopathy after a corneal cross-linking procedure, and the first to describe this phenomenon in a child with delayed corneal re-epithelialization. Though corneal cross-linking is a relatively safe procedure, atypical infections like crystalline keratopathy can occur in these patients in the setting of topical steroid use. Atypical organisms such as fungi should always be on the differential, especially for patients with recalcitrant infection in the setting of immunosuppression.
Corneal cross-linking is a procedure developed to halt or slow down the progression of corneal ectatic diseases. The procedure was created in 1998 and involves using riboflavin and ultraviolet (UV) irradiation to increase the stiffness of the cornea. Observational studies and randomized control trials (RCTs) have both shown sustained improvement after corneal cross-linking in measurements such as maximum simulated keratometry value (KMax), uncorrected visual acuity (UCVA), and best corrected visual acuity (BCVA). ,
Corneal cross-linking was approved by the Federal Drug Administration (FDA) in 2016 as a treatment for progressive keratoconus and post-surgical ectasia. Currently, Avedro’s KXL System (Waltham, Massachusetts, United States of America) is the only FDA approved device for these indications. The FDA-approved procedure using the Dresden protocol is the gold standard of treatment. Though the procedure is very safe, it does involve removal of the corneal epithelium to allow for application of riboflavin drops. Common complications include delayed epithelial healing, sterile infiltrates, and corneal haze, the latter of which is often transient. ,
Infectious keratitis is a rare but potentially serious consequence of corneal cross-linking, with a rate of 0.0017% according to one study. Infectious keratitis can lead to decreased visual acuity and corneal scarring, sometimes requiring corneal transplantation. Several case reports have shown S.Epidermidis, S. Aureus, Pseudomonas, Acanthamoeba, E. Coli, and Herpes Simplex Virus (HSV) as pathogens implicated in infectious keratitis after corneal cross-linking, with one case report of fungal keratitis in the US with Alternaria, and some reports of Fusarium and Microsporidia internationally. , Presently, there are only two reports of a primary infectious crystalline keratopathy following cross-linking. , In both cases, the patients initially healed well, but presented for their monthly exam with new intrastromal lesions and photophobia. Additionally, Steinwender and colleagues reported one case of infectious crystalline keratopathy in a large series that occurred after the patient had resumed wearing a rigid gas permeable contact lens. Risk factors for infectious crystalline keratopathy include immunocompromise, long term steroid use, post-surgical keratitis, contact lens wear, and topical anesthetic abuse. Fungal infectious crystalline keratopathy is exceedingly rare, with one study showing 3 out of 18 patients with the condition being of fungal origin.
The current case report presents an infectious crystalline keratopathy in a child with a prolonged post operative course.
A 14-year-old male with a history of keratoconus and corneal cross-linking in his left eye at an outside hospital, presented to our clinic 19 days post procedure for evaluation of a corneal infection and persistent haze. Per his records from his outside ophthalmologist, the patient had rubbed his eyes continually after surgery and had slow re-epithelialization and haze. He had been taking difluprednate four times a day, and tobramycin three times a day in the left eye. On examination at this initial visit, his uncorrected visual acuity (UCVA) was 20/70–2 and BCVA was 20/40 (−1.25–1.50 × 145) in the left eye. Slit lamp examination showed diffuse corneal haze, several well-demarcated intrastromal opacities (largest measuring 1.5 mm), and a 1.5 mm non-staining intrastromal branching lesion in the left eye ( Fig. 1 A). The patient had follow up scheduled with his outside ophthalmologist and was asked to return in a month should his symptoms persist.