Culture-Negative C acnes Endophthalmitis Following Implantation of a Phakic Implantable Collamer Lens

Abstract

Purpose:

This work describes a case of Cutibacterium acnes (formerly Propionibacterium acnes) endophthalmitis following a posterior-chamber, phakic, Implantable Collamer Lens (ICL) surgery.

Methods:

A 34-year-old previously healthy woman presented with chronic unilateral iritis 8 months after bilateral ICL surgery. Original testing revealed no cause for the iritis with normal culture, serology, and autoimmune testing results.

Results:

Follow-up revealed C acnes by polymerase chain reaction on vitrectomy samples. Complete resolution of symptoms was achieved following removal of the implant, lensectomy, and intravitreal antibiotics.

Conclusions:

We believe this is the first reported case of postphakic ICL C acnes endophthalmitis. It highlights the utility of polymerase chain reaction in cases of chronic uveitis.

Introduction

The Implantable Collamer Lens (ICL) has been established as a safe and effective alternative to keratorefractive surgery. The procedure has demonstrated high efficacy, including patient-centered metrics like improved quality of life and improved vision. ^1,2 Reported complications of phakic ICL implantation are fairly infrequent, including cataract formation in about 5.2% of cases, increased ocular pressure, pigment dispersion, pupillary block, and iritis. ^{3 -5} We present a case of Cutibacterium acnes (formerly Propionibacterium acnes) endophthalmitis that occurred following placement of an ICL and was diagnosed using polymerase chain reaction (PCR).

Methods

Case Report

A previously healthy 34-year-old woman developed unilateral anterior uveitis 5 months after elective Visian ICL (STAAR Surgical) placement in both eyes for myopia of –8 diopters. The initial procedure was uncomplicated and subsequent uncorrected visual acuities (VAs) were 20/20 in each eye. She developed painful anterior uveitis with keratic precipitates in the left eye 5 months postoperatively. The ICL, crystalline lens, and fundus were normal on examination. Treatment with topical prednisolone acetate was initially successful, but the iritis recurred. Eight months postoperatively, she was referred to a uveitis specialist for evaluation. The following studies for causes of uveitis had negative findings: complete blood count, erythrocyte sedimentation rate, serum angiotensin-converting enzyme, lysozyme, chest x-ray, rheumatoid factor, Lyme titers, Treponema pallidum antibodies, rapid plasma regain test, and QuantiFERON-TB Gold. Ultrasound biomicroscopy showed possible chaffing of the iris by the ICL. The ICL in the left eye was removed 10 months after the initial surgery. Bacterial, fungal, and acid-fast cultures of the explanted ICL all had negative results. She continued to develop worsening floaters and VA.

One year after ICL placement, her best-corrected VA was 20/20 OD and 20/200 OS. Findings from the right eye examination were normal with a well-positioned ICL. In the left eye, she now had 2+ vitritis with small deposits on the posterior surface of the natural lens (Figure 1). There was no focal retinal infiltrate or evidence of vasculitis. Owing to concern about an infectious etiology, a diagnostic vitrectomy was performed that was culture negative. A trial of oral prednisone resulted in only transient improvement of the uveitis, which worsened with tapering. A second vitrectomy, now combined with lensectomy, was performed. Cultures again had negative findings, but bacterial PCR testing was positive for C acnes. Treatment with intravitreal vancomycin 1 mg/0.1 mL and ceftazidime 2.25 mg/0.1 mL was administered.

Figure 1.

Deposits on the posterior natural lens 1 year after Implantable Collamer Lens placement.

Results

At 3 months’ follow-up, the patient had complete resolution of the ocular inflammation and treatments were discontinued. Her vision gradually recovered and at 1-year follow-up, her vision in the left eye was 20/20 with correction for aphakia.

Conclusions

Endophthalmitis is a rare complication of phakic ICL surgery, with one survey of surgeons estimating an incidence of 1 per 6000 cases. ⁶ The only reported postoperative endophthalmitis in the literature for phakic ICL surgical procedures were caused by Staphylococcus epidermidis. ^6,7

C acnes is a slow-growing anaerobe and the most common cause of chronic postcataract endophthalmitis. ⁸ Classic features include chronic iridocyclitis, keratic precipitates, and white plaques on the pseudophakic posterior capsule or on the implanted device. Similar findings in the posterior capsule of this patient’s natural lens were an important clue to an infectious etiology despite negative culture results. C acnes is notoriously difficult to culture, with 1 study having found a positive vitreous culture in only 24% of patients with delayed endophthalmitis after cataract surgery. ⁹ PCR has been shown to be valuable in diagnosing C acnes from ophthalmic sources, with the same study having found positive PCR in 92% of vitreous samples. ^9,10 There have been cases of C acnes endophthalmitis following cataract surgery that required PCR for detection. ^{11 -13}

To our knowledge, there has never been a report of C acnes endophthalmitis following phakic ICL implantation. This case of C acnes endophthalmitis is illustrative of 2 key points: (1) the utility of bacterial PCR testing for fastidious organisms in cases of idiopathic or smoldering postoperative uveitis, and (2) the occurrence of C acnes infection as a postoperative complication of phakic ICL surgery.