Borrelia-associated crystalline keratopathy with intracorneal detection of Borrelia garinii by electron microscopy and polymerase chain reaction.

Purpose: First report of a patient with Borrelia-associated crystalline keratopathy with intracorneal evidence of Borrelia garinii by polymerase chain reaction (PCR) and electron microscopy (EM).

Methods: Report of a 67-year-old patient with medical history of recurrent iridocyclitis and arthritis presented with a bilateral, progressive, asymmetric crystalline keratopathy, which was particularly pronounced in the peripheral temporal superior cornea. After penetrating keratoplasty, crystalline keratopathy with stromal haziness recurred. Corneal regrafting was performed. The corneal specimen from the penetrating keratoplasty was examined by light and EM as well as by PCR.

Results: In the explanted corneal graft, as well as retrospectively in the corneal specimen from the first keratoplasty, spirochetelike bodies and fragments were detected by light and EM. Borrelia burgdorferi sensu lato DNA was demonstrated by broad-range (16S rDNA) PCR. A more precise identification as Borrelia garinii serotype 5 was possible by analyses of the flaB and ospA gene sequences. Borrelia-specific serological tests showed borderline titers in immunofluorescence and weak reaction in immunoblot, respectively.

Conclusions: This case illustrates that borreliae must be considered as a cause of crystalline keratopathy; Borrelia-specific serological tests can be false negative; explanted cornea specimens of etiologically unclear crystalline keratopathy should be analyzed by EM or PCR for detection of pathogens; and prolonged antibiotic treatment might be effective to prevent progression or recurrence of the disease.