Risk factors, clinical features, and outcomes of recurrent fungal keratitis after corneal transplantation

Purpose: To study the risk factors, clinical features, and treatment of recurrent fungal keratitis after corneal transplantation.

Design: Retrospective, interventional case series.

Participants: Eight hundred ninety-nine patients (eyes) with fungal keratitis who underwent corneal transplantation at the Shandong Eye Institute between January 2000 and October 2008. Six hundred fourteen patients underwent penetrating keratoplasty (PK) and 285 patients underwent lamellar keratoplasty (LK).

Methods: All patients failed to respond to topical and systemic antifungal drugs treatment before corneal transplantation. A trephine that was 0.5 mm larger in diameter than the infection area was used during PK or LK. Medical records of each patient were reviewed retrospectively. The species of pathogenetic fungi causing recurrence were analyzed. The clinical features, including recurrence time, position, symptom, and physical signs, were summarized. Based on clinical features, appropriate topical and systemic antifungal treatment was determined for all patients; some patients also received combined subconjunctival or intracameral injection of fluconazole. If there was treatment failure, a conjunctival flap or keratoplasty was performed.

Main outcome measures: Species of pathogenetic fungi, clinical features, and apparent therapeutic effects.

Results: Fifty-seven patients (6.34%) experienced recurrence after corneal transplantation. There was no difference between PK (6.79%) and LK (5.96%) in recurrence rate (P = 0.883). A higher rate of recurrences was found in those with preoperative hypopyon (10.90%), corneal perforation (12.00%), corneal infection expanding to limbus (20.69%), or lens infection with extracapsular cataract extraction (50%; P<0.05). The 3 main kinds of recurrence were: (1) recurrent infection from recipient bed to graft, and once recurrent infection invaded the graft, the inflammation progressed more rapidly; (2) white mushroom-shaped hypopyon with anterior chamber recurrence; (3) infection in the posterior chamber and vitreous opacity on posterior segment recurrence. Location of recurrence was: recipient bed (70.18%), anterior chamber (7.02%), and posterior segment (22.81%). The overall cure rate was 82.46%, which included drug therapy (28.07%) and surgical treatment (54.39%).

Conclusions: Hypopyon, corneal perforation, corneal infection expanding to limbus and lens infection are major risk factors for recurrence of fungal keratitis after corneal transplantation. Based on the clinical features of recurrence, appropriate treatment options can help to control the recurrent infection.