Purpose: To study intravitreal dexamethasone and vancomycin concentrations,when used together in patients with suspected postoperative bacterial endophthal mitis. Animal studies had suggested that dexamethasone might ...Purpose: To study intravitreal dexamethasone and vancomycin concentrations,when used together in patients with suspected postoperative bacterial endophthal mitis. Animal studies had suggested that dexamethasone might decrease the concentration of vancomycin. Design: Prospective randomized clinical trial in a tertiary referral center. Methods: Twenty-nine consecutive patients with suspected postoperative bacterial endophthalmitis underwent a vitreous biopsy followed by intravitreal injection of antibiotics (0.2 mg vancomycin,0.05 mg gentamicin) and 400 μ g dexamethasone or placebo. After 3-4 days,the intravitreal injection of antibiotics and dexamethasone or placebo was repeated. In 18 patients,a second biopsy was taken for repeat culture and measurement of vancomycin and dexamethasone concentrations. Results: In 20/29 patients (69% ) the first vitreous cultures were positive; the second culture was negative in all cases. Thirteen outof 29 patients received dexamethasone. Dexamethasone concentrations showed an average of 25 ng/ml 3 days after injection,with an estimated half-life of 5.5 h. Vancomycin concentrations in patients given dexamethasone tended to be higher compared with those in the placebo group (P=0.061). Conclusion: Intravitreal dexamethasone does not lead to decreased vancomycin concentrations,when given simultaneously in the treatment of patients with suspected bacterial endophthalmitis.展开更多
文摘Purpose: To study intravitreal dexamethasone and vancomycin concentrations,when used together in patients with suspected postoperative bacterial endophthal mitis. Animal studies had suggested that dexamethasone might decrease the concentration of vancomycin. Design: Prospective randomized clinical trial in a tertiary referral center. Methods: Twenty-nine consecutive patients with suspected postoperative bacterial endophthalmitis underwent a vitreous biopsy followed by intravitreal injection of antibiotics (0.2 mg vancomycin,0.05 mg gentamicin) and 400 μ g dexamethasone or placebo. After 3-4 days,the intravitreal injection of antibiotics and dexamethasone or placebo was repeated. In 18 patients,a second biopsy was taken for repeat culture and measurement of vancomycin and dexamethasone concentrations. Results: In 20/29 patients (69% ) the first vitreous cultures were positive; the second culture was negative in all cases. Thirteen outof 29 patients received dexamethasone. Dexamethasone concentrations showed an average of 25 ng/ml 3 days after injection,with an estimated half-life of 5.5 h. Vancomycin concentrations in patients given dexamethasone tended to be higher compared with those in the placebo group (P=0.061). Conclusion: Intravitreal dexamethasone does not lead to decreased vancomycin concentrations,when given simultaneously in the treatment of patients with suspected bacterial endophthalmitis.
