Thygeson's superficial punctate keratitis (TSPK): a paediatric case report and review of the literature

Thygeson's superficial punctate keratitis in children

OBJECTIVE

To describe the first paediatric case series of Thygesons' superficial punctate keratitis (TSPK) with management outcomes.

METHODS

A retrospective chart review was done for all children either diagnosed at initial presentation or referred with TSPK from 01/2012 to 08/2021 at a tertiary children's hospital. Records were assessed for signs, symptoms, diagnosis, steroid and cyclosporine 0.05% use. The main outcome measures were visual acuity, treatment response and total steroid exposure.

RESULTS

Fifteen children (7 females), mean age at presentation 8 ± 4 years were included. All had bilateral disease and a BCVA of >20/40 in the better eye. All patients received topical fluorometholone 0.1%, (FML) initially. 80% had a good response to FML. Corneal scraping was done to exclude infectious causes in four cases due to poor initial response or clinical suspicion. All 4 needed EUA for scraping and anterior segment OCT, after which 2 had molecularly confirmed TGFBI-related stromal dystrophy. For the rest, slow steroid taper was done every 4-6 weeks and recurrences were treated by increasing steroid frequency. Cyclosporine 0.05% was started in nine patients (69%), 8 ± 6 months after initial presentation. The decrease in total steroid exposure per week after starting cyclosporine was statistically significant (p < 0.05).

CONCLUSION

Children with TSPK respond quickly to steroids, however, recurrences are common, necessitating a slow taper. Non-response to steroid needs careful reconsideration of the diagnosis and may necessitate the use of an EUA. Using cyclosporine 0.05% reduces the total steroid exposure in TSPK.

Treatment of immune-mediated keratitis (IMMK) in dogs with immunosuppressants observed with spectral domain optical coherence tomography (SD-OCT)

Two dogs presented with bilateral pattern-forming corneal opacity. Treatment with topical immunosuppressants was initiated after a complete ophthalmic examination. The response to treatment was assessed by analyzing serial images using slit-lamp biomicroscopy and spectral domain optical coherence tomography (SD-OCT). Both dogs responded to topical immunosuppressants; however, the lesions recurred once the treatment was abated or withdrawn. The most effective immunosuppressant in both dogs was 0.03% tacrolimus ointment. Early and continuous treatment with topical immunosuppressants may be necessary to improve corneal clarity and prevent scarring. SD-OCT could provide useful structural information regarding presumed immune-mediated keratitis and aid in monitoring treatment response.

Thygeson Superficial Punctate Keratitis: A Clinical and Immunologic Review

ABSTRACT

Thygeson superficial punctate keratitis (TSPK) is clinically characterized by exacerbations and remissions of gray-white opacities within the corneal epithelium, most often bilateral but may be asymmetric. Symptoms typically include photophobia, tearing, blurring, and eye irritation. Although disease progression and prognosis are well described, the exact cause is unknown. Hypotheses exist implicating virus-mediated immunity as the cause of TSPK following cases of viral keratitis; however, several polymerase chain reaction studies refute the infectious process concurrently with symptomatic TSPK. This is further supported by the consistent lack of response to antiviral and antibacterial treatment. A subset of dendritic cells known as Langerhans cells (LC) found within the corneal epithelium has been positively correlated with exacerbations of TSPK. Langerhans cells proliferate to protect and mitigate the cornea's inflammatory response, but the inflammatory triggers and relapses associated with TSPK are not well understood. Several topical drugs exist to treat inflammation related to TSPK; however, drug delivery is a major barrier to treatment because of the tear film and epithelial barrier. Drug-eluting contact lenses that target intermediates of inflammation could serve as a more effective treatment modality because of the increased bioavailability of the drugs. This review is an in-depth survey of the literature regarding the relationship between the origin and pathophysiology of LC and TSPK at the immunologic level. We also discuss potential pharmacotherapeutic interventions for TSPK prevention and treatment.