Infectious Crystalline Keratopathy Caused by Streptococcus Abiotrophia defectiva

Abstract

To report the first case of Streptococcus Abiotrophia defectiva-associated crystalline keratopathy. An 83-year-old woman underwent penetrating keratoplasty for pseudophakic bullous keratopathy in the OD. Ten months after surgery, the patient presented with decreased visual acuity in the OD. Slit-lamp examination showed crystalline keratopathy. Corneal scrapings were negative, and the patient was treated empirically with 2 fortified antibiotics (ciprofloxacin and vancomycin). Despite these treatments, the surface of the infiltrate increased and corneal regrafting was performed 6 weeks later. The excised prior graft was evaluated microbiologically [culture and polymerase chain reaction (PCR)] and histopathologically. In the explanted corneal graft, cultures grew Streptococcus A. defectiva, and its DNA was demonstrated by broad-range PCR (16S ribosomal DNA). A. defectiva can be a causative organism of infectious crystalline keratopathy. Risk factors may include long-term corticosteroid use and prior corneal transplantation. The present case confirms that PCR can be a useful technique in the diagnosis of deep infectious keratitis.