Amniotic membrane transplantation in a patient with an impending perforated corneal ulcer caused by Streptococcus mitis: a case report

Background: Streptococcus mitis (S. mitis) belongs to the viridans group streptococci, which is rarely isolated as a causative pathogen of corneal ulcers. When S. mitis causes keratitis, penetrating keratoplasty (PK) might be necessary. Herein, we demonstrated that amniotic membrane transplantation (AMT) may be an easier procedure with acceptable outcomes and with fewer complications. Case presentation: A 63-year-old female presented with a right persistent corneal ulcer that she had suffered from for the past nine months. The culture of a corneal scraping yielded S. mitis. The right eye descemetocele decreased from 3 mm in diameter to 0.8 mm in diameter after the continuous administration of topical vancomycin and ceftriaxone for two weeks. Due to the slow healing, AMT was performed. Her corneal erosion healed and gradually became clear. Her visual acuity recovered from initially counting fingers to 20/200 17 months after AMT. Conclusion: This unusual case illustrated that antibiotics plus AMT may be an effective alternative treatment instead of PK to promote epithelialization and to reduce inflammation in corneas complicated by S. mitis keratitis.