Analysis of etiology and in vitro drug resistance of ocular fungal infection in period of 2009 - 2010

Abstract

To analyze the distribution and shifting trends of fungal culture specimens and assess the drug sensitivity in vitro. Case series study. From January 2009 to December 2010, 1302 specimens were collected. These specimens were cultured on potato dextrose agar medium under 28°C and 40% humidity for 3 - 8 days. Drug sensitivity of positive cultures were evaluated by K-B method. Chi-square test was used for the analysis. In 1302 specimens, 292 samples (22.4%) were culture-positive, in which 69.9% were isolated from the cornea, 3.8% from the vitreous body, 1.0% from the anterior chamber, 0.7% from the conjunctiva, 0.7% from palpebral margin and 24.0% from other parts of the eye. Culture-positive rate of 2009 and 2010 were 21.2% (135/637) and 23.6% (157/665) respectively with no statistically significant difference (χ(2) = 1.092, P = 0.296). Two peaks of culture-positive outcome appeared in May and November. Culture results showed that Fusarium sp. was the commonest pathogen (59.6%, 174/292), Aspergrium sp. in 16.8% (49/292) and Alternaria sp.in 10.6% (31/292). Patients from 31 to 60 years old accounted for 82.2% (240/292) of positive cases. The sensitive rate in vitro to natamycin, terbinafine, fluconazole, amphotericin B and itraconazole was 94.0% (63/67), 63.4% (154/ 243), 6.0% (17/285), 39.7% (98/247) and 21.2% (65/306), respectively. The top three commonest fungus of Beijing Tong Ren hospital successively are Fusarium sp., Aspergrium sp. and Alternaria sp. Natamycin should be the first choice for fusarium infection and pathogen-unknown infection. All species with the exception of Fusarium sp. are sensitive to natamycin, terbinafine and amphotericin B but not itraconazole. Almost all fungal strains are resistant to fluconazole.