OBJECTIVE: To study the distribution and shifting trends of corneal bacterial isolates from bacterial keratitis retrospectively. METHODS: The data of bacterial cultures of 2 220 corneal isolates from January, 1989 to December, 1998 were reviewed. RESULTS: During this 10-year period, 2 220 consecutive corneal cultures were obtained, and a positive-culture was recovered in 490 isolates, the positive rate being 22.1%. In the 490 positive-cultures, Gram-positive cocci and Gram-negative bacilli represented 51.0% and 39.4% respectively. Gram-positive bacilli was 9.2%. Pseudomonas aeruginosa was isolated the most commonly in the corneal isolates (32.2%), followed by coagulase-negative staphylococcus (18.6%). Streptococcus pneumoniae represented 12.0%. During this period, we documented a gradual increase in the number of Gram-positive cocci coupled with a decrease of the number of Gram-negative bacilli. CONCLUSION: Pseudomonas aeruginosa and coagulase-negative staphylococcus are the most common pathogens in bacterial keratitis in the north part of China. At present, the increased recovery of Gram-positive cocci and decreased of Gram-negative bacilli from keratitis isolates present an important challenge to the ophthalmology.
OBJECTIVE: To study the distribution and shifting trends of corneal bacterial isolates from bacterial keratitis retrospectively. METHODS: The data of bacterial cultures of 2 220 corneal isolates from January, 1989 to December, 1998 were reviewed. RESULTS: During this 10-year period, 2 220 consecutive corneal cultures were obtained, and a positive-culture was recovered in 490 isolates, the positive rate being 22.1%. In the 490 positive-cultures, Gram-positive cocci and Gram-negative bacilli represented 51.0% and 39.4% respectively. Gram-positive bacilli was 9.2%. Pseudomonas aeruginosa was isolated the most commonly in the corneal isolates (32.2%), followed by coagulase-negative staphylococcus (18.6%). Streptococcus pneumoniae represented 12.0%. During this period, we documented a gradual increase in the number of Gram-positive cocci coupled with a decrease of the number of Gram-negative bacilli. CONCLUSION:Pseudomonas aeruginosa and coagulase-negative staphylococcus are the most common pathogens in bacterial keratitis in the north part of China. At present, the increased recovery of Gram-positive cocci and decreased of Gram-negative bacilli from keratitis isolates present an important challenge to the ophthalmology.