To report a case of syphilitic interstitial keratitis successfully managed with topical tacrolimus after the development of steroid-induced intraocular pressure elevation in a pediatric patient.
A 4-year-old female with a history of congenital syphilis that was reportedly treated after birth presented with bilateral conjunctival redness, tearing, and photosensitivity. Initial ophthalmic examination revealed corneal vascularization with diffuse haze of the right eye and circumferential vascularization with stromal infiltrates of the left eye. She was diagnosed with bilateral syphilitic interstitial keratitis and initially managed with topical steroids but developed steroid-induced elevation of her intraocular pressure. She experienced several recurrences of keratitis as steroids were tapered. After a recurrence in her right eye, she was treated with topical tacrolimus. Since then, she has remained recurrence-free for almost three years with normal intraocular pressure.
Conclusion and importance
Tacrolimus represents a novel alternative for the treatment of syphilitic interstitial keratitis, which is particularly useful in patients that develop elevated intraocular pressures in response to long-term treatment with steroid eye drops.
Interstitial keratitis is a chronic, stromal inflammation mediated by an autoimmune reaction that may lead to permanent corneal scarring. Typical etiologies of interstitial keratitis include herpes simplex virus, varicella zoster virus, syphilis, and idiopathic. Though the mechanism is poorly understood, laboratory studies have revealed changes to the corneal anatomy including vascularization of deep stromal lamellae, thickening of the Descemet membrane with an altered collagen profile, and retrocorneal scrolls.
Cases are typically managed by treatment of the underlying condition, topical or systemic immunosuppression, and management of the side effects of treatments. Complications of management include recurrences of interstitial keratitis, corneal scarring, and glaucoma. Our case is an example of the common management and complications of management of this disease. We present a novel therapeutic modality for syphilitic interstitial keratitis, tacrolimus, which may avoid common treatment complications.
A 4-year-old female adopted at 15-months-old from South Korea presented with a six-week history of bilateral eyelid swelling associated with conjunctival redness, tearing, and photosensitivity. Her medical history included premature birth at 31 weeks and congenital syphilis, reportedly treated although the exact therapeutic regimen was unknown. After being adopted, RPR testing and skeletal X-rays were found to be negative and a Treponema particle agglutination (TP-PA) test was reactive, consistent with successfully treated congenital syphilis. However given the unknown therapeutic regimen, a course of IV penicillin was administered.
On presentation, the patient was noted to have a visual acuity of 20/60 in the right eye (OD) and 20/25 in the left eye (OS). Given difficulty with the office exam due to photosensitivity, an exam under anesthesia was performed. On portable slit lamp exam, there was extensive right corneal vascularization with diffuse haze and a dense S-shaped haze along the superior pupillary border. The left eye had circumferential vascularization with stromal infiltrates at the border of the vessels; however, the central portion of the left cornea was clear. Aside from 2+ bilateral conjunctival injection, the remainder of the ocular exam was normal. Her refractive error was noted to be +4.25 sphere OD and +3.25 sphere OS. Intraocular pressures were 20 mmHg OD and 15 mmHg OS.
In light of her history, her findings were consistent with bilateral interstitial keratitis secondary to congenital syphilis. She was treated with topical prednisolone acetate 1 % and cyclopentolate in both eyes (OU). Both her photosensitivity and conjunctival injection improved markedly on this therapy. Her refractive error was noted to decrease to +0.75 + 0.50 × 087 OD and +0.50 sphere OS. After one month of therapy, she was noted to have a visual acuity of 20/20 OU with stromal haze sparing the visual axis OD and resolution of corneal haze OS. Her drops were weaned over a period of one month.
Over the following three years, she developed several episodes of recurrent keratitis in both eyes, although this was typically asymmetric, with keratitis more often needing treatment in the right eye than the left eye. At her nadir, her visual acuity worsened to 20/80 in the right eye and 20/30 in the left eye. Additionally after a recurrence OD, she was noted to develop a large refractive shift over six months to −4.50 + 6.00 × 100 OD, while the left eye refraction remained relatively stable.
The keratitis required treatment with multiple rounds of topical prednisolone acetate 1 % which remained effective in controlling the inflammation; however, the patient developed steroid-induced intraocular pressure (IOP) elevation, with eye pressure maximally elevated to 32 mmHg OD and 45 mmHg OS (Baseline IOP was 13 mmHg OU). Elevated IOP was lowered with the addition of topical dorzolamide, latanoprost and timolol. While elevation of IOP was not marked with prednisolone 0.12 % or the subsequent use of loteprednol, these medications were not adequate to maintain disease quiescence.
After the patient developed a severe recurrence of keratitis with extension into the visual axis in her left eye, treatment with oral systemic prednisone 0.5 mg/kg/day was initiated with resolution of keratitis. Following a two-month taper of systemic corticosteroids, the patient stayed in remission for several months with daily loteprednol; however, she then developed a keratitis relapse in her right eye with decrease of vision to 20/80 ( Fig. 1 ). Treatment with systemic prednisone again restored quiescence and the patient was started on topical cyclosporine 0.05 % twice daily in the right eye one month into her oral steroid taper; however, cyclosporine also proved inadequate to maintain quiescence, with her exam exhibiting worsened stromal haze, vascularization of the cornea, and decline in best corrected visual acuity to 20/60.