Spectrum of fungal keratitis in north China

To report the epidemiological features, laboratory findings, and treatment outcomes in patients with fungal keratitis in north China.

Retrospective hospital-based study.

A total of 654 patients diagnosed with fungal keratitis at the Shandong Eye Institute from January 1999 to December 2004.

The medical records of 654 inpatients (654 eyes) with fungal keratitis were reviewed retrospectively for demographic features, risk factors, seasonal variation, clinical characteristics, laboratory findings, and treatment strategy.

Patient history, ocular examination findings by slit-lamp biomicroscopy, laboratory findings from direct smear examination and fungal culture, and treatment protocol.

Fungal keratitis constituted 61.9% of cases of severe infective keratitis among the inpatients at the Shandong Eye Institute during the 6 years. Males (60.6%) were more likely to be affected by fungal keratitis than females (39.4%). Almost one third of the patients (203) were middle aged (41-50 years old). Corneal trauma (51.4%), especially injury from plants (25.7% in all patients), was the most commonly associated risk factor. The incidence of fungal keratitis was higher in harvest seasons, including summer and autumn. An increasing tendency of incidence was noted in more recent years. Direct microscopic examination of the corneal scraping samples stained with potassium hydroxide showed positivity in 88.7% of the eyes. The fungal isolates were of Fusarium species in 437 eyes (73.3%) and Aspergillus species in 72 eyes (12.1%). Surgical interventions were performed in 604 eyes (92.4%), including therapeutic penetrating keratoplasty in 399 eyes (66.0%) and therapeutic lamellar keratoplasty (LK) in 177 eyes (29.3%). Globe integrity was preserved in 626 eyes (95.7%).

With Fusarium species being the most commonly isolated pathogens, fungal keratitis is the leading cause of severe infective corneal ulcers in north China. Direct microscopic examination with potassium hydroxide wet mounts proves to be a rapid, simple, inexpensive diagnostic means. Corneal transplantation continues to be the most effective approach for the treatment of severe fungal keratitis. Early surgery, especially LK, can be considered if aggressive topical therapy does not achieve early disease control.