Retinoschisis associated with Kearns-Sayre syndrome

BACKGROUND: Kearns-Sayre Syndrome (KSS) is characterized by pigmentary retinopathy, external ophthalmoplegia and heart block. We report on a now 24-year-old male with clinical retinoschisis and molecularly confirmed KSS. MATERIALS AND METHODS: Physical and complete ophthalmic examination, molecular diagnosis. RESULTS: Over nine years of follow-up, the subject manifested progressive signs and symptoms of KSS, including external ophthalmoplegia/strabismus, ptosis, pigmentary retinopathy, corneal edema, Type I diabetes mellitus, gut dysmotility, sensorineural deafness and heart block. At age 21 he was incidentally found to have retinoschisis on optical coherence tomography that remained stable over three years follow-up. Sequencing of the RS1 gene revealed no pathogenic variants, effectively ruling out co-existing X-linked retinoschisis. CONCLUSIONS: These findings suggest retinoschisis may be a rare manifestation of KSS. A trial of a carbonic anhydrase inhibitor was frustrated by coexisting corneal edema associated with the condition.