Managing Recurrent Fungal Keratitis: Multiple Intrastromal Injections Of Voriconazole In A Post Penetrating Keratoplasty Patient With Graft Failure And Uncontrolled Diabetes Mellitus

To report recurrent fungal keratitis in a patient diagnosed with graft failure after penetrating keratoplasty and uncontrolled diabetes. The atypical corneal healing and the management of its complications in this case may aid in the successful management of similar complex cases.

In cases of severe fungal keratitis, where therapeutic keratoplasty has been performed, the threat of fungal keratitis still remains as the disease may recur in 10-15% of these cases. Moreover, systemic comorbidities such as uncontrolled diabetes may pose additional challenges to the post operative management of penetrating keratoplasty, hindering effective treatment

A 55/F asian diabetic female underwent therapeutic penetrating keratoplasty (PKP) for fungal keratitis. Due to poor compliance with medications and infrequent follow-up, the occurrence of graft rejection was missed, and she returned months after surgery with graft failure and a visual acuity of hand movement.  One year post penetrating keratoplasty, the patient presented with eye pain, a central 5x5 mm corneal lesion with feathery borders, and 3mm hypopyon, indicating recurrence of fungal keratitis on the corneal graft. Fasting blood glucose was as high as 312 mg/dL at time of examination.

Patient was managed systemically, combined with frequent debridement of the corneal lesion, intrastromal injections of voriconazole, topical natamycin and levofloxacin 1.5%. A total of 12 intrastromal injections of voriconazole (50-100 mcg/0.1mL) was given over six weeks. Recovery was slowly achieved with reduction in size of corneal infiltrates, complete resolution of satellite lesions and hypopyon, and a reduction in corneal opacity. Glucose levels also gradually stabilized (<120 mg/dL) after 5 weeks of insulin therapy.

Atypical corneal healing is present in uncontrolled diabetes, which increases susceptibility for microbial keratitis. Managing fungal keratitis is difficult as resources are not readily available in all settings. Typically intrastromal injections of anti-fungal medications are only given for 3-5 doses. However, extending and combining multiple modalities of treatment may be beneficial in complex cases. A combination of multiple intrastromal voriconazole injections, topical antimicrobials combined with strict glucose control and extended treatment may be considered a viable approach in similar cases.