Streptococcus agalactiae Endophthalmitis in Boston Keratoprosthesis in a Patient with Steven-Johnson Syndrome.

A 25-year-old Syrian male with a previous episode of Stevens-Johnson syndrome with bilateral corneal cicatrization previously underwent surgery for Type 1 Boston Keratoprosthesis (K-Pro). Sixteen months after the K-Pro surgery, the patient presented with decreased vision to hand motion and microbial keratitis of the graft around the K-Pro with purulent discharge. Corneal scrapings were nonrevealing. B-scan in 3 days showed increased debris in the vitreous cavity and thickened retinochoroidal layer. Intravitreal tap and injections of vancomycin and ceftazidime were performed. The vitreous culture revealed β-hemolytic Streptococcus agalactiae; fungal cultures were negative. Repeat B-scan 3 days later demonstrated decreased vitreous opacity, and the patient felt more comfortable and was without pain. His visual acuity improved to 20/70, ocular findings have been stable for 9 months, and the patient continues to be monitored.

Introduction

Keratoprosthesis (K-Pro) surgery is generally reserved for eyes with advanced disease that have undergone multiple attempts at surgical reconstruction. The serious ocular pathology found in such patients leads to potential postoperative complications which include an increased risk of glaucoma,[1] tissue melt with aqueous leak,[2] device extrusion, chronic inflammation and membrane formation,[3] retinal detachment,[4] macular edema, keratitis, and bacterial endophthalmitis.[56] Rates of endophthalmitis following placement of K-Pro vary from 0% to 12.5% in published literature.[78910] Herein, we report a so far undescribed case of endophthalmitis caused by Streptococcus agalactiae in a patient with Boston K-Pro due to severe corneal scarring in Stevens-Johnson syndrome.

Case Report

A 25-year-old male with a previous episode of Stevens–Johnson syndrome with bilateral corneal cicatrization presented complaining of decreasing vision in his (better) left eye. His visual acuity in the right eye (oculus dexter) was hand motion (HM) [Figure 1a], and in his left eye (oculus sinister) HM with pinhole improvement to 20/300. In this eye, the patient had four failed corneal grafts (including tectonic penetrating keratoplasty, amniotic membrane transplant, and bandage contact lens [BCL]) and trabeculectomy for secondary glaucoma 7 months previously [Figure 1b]. The patient underwent surgery for Type 1 Boston K-Pro in his left eye, with improvement of vision to 20/70.

Figure 1

Slit-lamp photograph of right eye of the patient with Stevens–Johnson syndrome showing corneal scarring, neovascularization, and symblepharon. Visual acuity is hand motion (a). Left eye of the same patient before Boston keratoprosthesis surgery shows corneal haze, neovascularization, and cystic stromal changes (b)

The patient suffered from severe dry eye postoperatively, which was managed with lubricants, topical corticosteroids but no BCL, or topical antibiotic prophylaxis. Sixteen months after the K-Pro surgery, the patient presented with decreased vision to HM and microbial keratitis of the graft around the K-Pro with purulent discharge [Figure 2a]. The palpebral conjunctiva was keratinized with corneal neovascularization and extremely chemotic bulbar conjunctiva. He was placed on fortified topical moxifloxacin hourly, lubrication, and systemic fluoroquinolone antibiotics. The eye was mildly hypotonous and B-scan ultrasound showed possible choroidal detachment. Corneal scrapings were nonrevealing. Repeat B-scan in 3 days showed resolved choroidals but increased debris in the vitreous cavity and thickened retinochoroidal layer. For this and increasing ocular pain, intravitreal tap and injections of vancomycin and ceftazidime were performed. Two days after the procedure, the vision was the same with decreased ocular pain. The vitreous culture revealed β-hemolytic S. agalactiae; fungal cultures were negative. Repeat B-scan 3 days later demonstrated decreased vitreous opacity, and the ocular examination showed improved chemosis; the patient felt more comfortable and was pain free. He continued with topical antibiotics and was discharged in a week. On follow-up visit 2 weeks later, the patient was pain free, vision improved to 20/200, and anterior segment was quiet [Figure 2b]. His visual acuity improved to 20/70, ocular findings have been stable for 9 months, and the patient continues to be monitored.

Figure 2

Slit-lamp photograph of left eye of the patient with Steven–Johnson syndrome with Boston keratoprosthesis that developed acute bacterial endophthalmitis with blepharitis, conjunctival chemosis, hyperemia, and discharge. Visual acuity dropped to 20/300 (a). The same eye after the treatment with fortified topical and intravitreal antibiotics shows improved blepharitis, no hyperemia and ocular surface free of purulent discharge. Visual acuity improved to 20/70 (b)

Discussion

K-Pro surgery allows for visual recovery in patients who do not have other options for vision restoration. While advances have been made in the areas of prosthesis design, surgical technique, and postoperative management, patients with K-Pro still maintain a lifetime risk of endophthalmitis. A review by Robert et al. reviewed all reported cases of endophthalmitis after placement of a K-Pro from 2001 to 2011, and calculated the overall rate to be 5.4% during that 10-year period.[11]

Some studies have suggested that the rates of endophthalmitis depend on the initial indication for placement of the K-Pro. Nouri et al. reported that while the overall rate in their total cohort was 12%, the incidence was 39% in those who had K-Pro for complications due to Stevens–Johnson syndrome, 19% for ocular cicatricial pemphigoid, and 17% in burn patients.[6] The findings by Greiner et al. did not corroborate this finding.[8] Our patient had chronic ocular surface changes due to Stevens–Johnson syndrome which resulted in blindness in one eye and severe scarring in the left eye. Moreover, he had a history of trabeculectomy surgery for secondary glaucoma, which is another predisposing factor for postoperative infection. As such, he was in a higher risk group for postoperative complications including endophthalmitis. Lifetime prophylactic use of topical antibiotics has been previously discussed in literature.[12]

Time from K-Pro placement to development of endophthalmitis ranges from as little as 6 weeks to as late as 46 months.[12] Ramchandran et al.[7] reported an average time to presentation with endophthalmitis after K-Pro implantation of 9.8 months. Our patient developed endophthalmitis 14 months after K-Pro surgery.

The most commonly encountered organisms are Gram-positive cocci.[10] Durand et al.[12] reported an 83% rate of Gram-positive cocci, 67% of which were streptococci. Gram-negative organisms, such as Pseudomonas spp. and Serratia marcescens, have also been described in the setting of K-Pro-associated endophthalmitis.[12] The vitreous sample in our patient revealed colonies of S. agalactiae, which has not previously been associated with K-Pro endophthalmitis.

Fungal organisms are also an important cause of K-Pro-associated endophthalmitis. It is suggested that the use of broad-spectrum antibiotic therapy and the continuous use of contact lenses and topical steroids may increase the incidence of keratoprosthetic fungal colonization.[1314] In the case series by Barnes et al., the rate of fungal keratitis and endophthalmitis was higher in eyes receiving a vancomycin-containing topical prophylactic regimen compared with those on a nonvancomycin-containing regimen.[13]

Many patients with K-Pro-associated endophthalmitis are treated with the standard endophthalmitis treatment used with postcataract endophthalmitis. This regimen typically includes tap and inject with intravitreal vancomycin and ceftazidime. Our patient responded well to this regimen. Some eyes also receive intravitreal amphotericin.[710] Georgalas et al.[15] described performing 25-gauge vitrectomy for endophthalmitis in the setting of K-Pro given the potential severity of K-Pro-associated endophthalmitis and given the difficulty of examination of these patients. They report a good postoperative outcome and stability during the postoperative course, suggesting that 25-gauge vitrectomy is a possible initial therapeutic approach to endophthalmitis in the setting of K-Pro. The option of surgery was not pursued in our patient due to the finding of shallow choroidal detachment at the time of intervention.

In the series by Durand and Dohlman,[12] the only patients who regained excellent vision had Staphylococcus epidermidis endophthalmitis. In three cases by Chan and Holland, two resulted in light perception vision. One patient recovered vision to 20/60.[16] Overall, the recovery rate varies by study, but devastating visual outcomes are common. Recurrent endophthalmitis in the setting of a K-Pro has also been reported by Ramchandran et al.[7]

Conclusion

We present a case of Boston K-Pro-associated endophthalmitis due to a previously unreported organism that was successfully managed with intravitreal antibiotic therapy in combination with topical and systemic therapy.

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Conflicts of interest

There are no conflicts of interest.