Evaluation of vitreous levels of gatifloxacin after systemic administration in inflamed and non-inflamed eyes.
OBJECTIVE
This study aimed to evaluate the human vitreous penetration of gatifloxacin in inflamed and non-inflamed eyes after oral administration.


METHODS
Vitreous penetration of single-dose (400 mg) oral gatifloxacin was evaluated in patients (n = 33) undergoing vitreous tap during the standard procedure for intravitreal antibiotic injection for acute postoperative endophthalmitis at various time-points. Vitreous penetration of 400 mg oral gatifloxacin was evaluated in the non-inflamed eyes of patients (n = 33) undergoing pars plana vitrectomy at similar time-points. The study was extended to evaluate the vitreous penetration of single-dose oral (800 mg) gatifloxacin at a single time-point in inflamed (n = 10) and non-inflamed (n = 11) eyes.


RESULTS
After 400 mg oral gatifloxacin, inflamed eyes showed mean vitreous concentrations of 0.58+/-0.19 microg/ml, 1.33+/-0.33 microg/ml and 1.30 +/- 0.23 microg/ml at 2, 4 and 6 hours, respectively. The levels reached at 2 and 4 hours were found to be significantly increased compared with those in non-inflamed eyes. At the 800-mg dose, 4-hour vitreous levels in inflamed and non-inflamed eyes were 1.57 +/- 0.3 microg/ml and 1.42 +/- 0.24 microg/ml, respectively. Although the increased dose of gatifloxacin elevated plasma concentration, it failed to raise vitreous levels significantly higher than the 400-mg dose at the 4-hour time-point.


CONCLUSIONS
Orally administered gatifloxacin achieves therapeutic levels in both inflamed and non-inflamed human eyes with a spectrum covering the bacterial species most frequently involved in the various causes of endophthalmitis. However, the levels achieved were below the MIC(90) for Pseudomonas aureginosa and Enterococcus.
Rajpal
Department of Vitreoretinal Diseases and Trauma, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Srinivas
Ambatipudi
A
Azad
Raj Vardhan
RV
Sharma
Yog Raj
YR
Kumar
Atul
A
Satpathy
Gita
G
Velpandian
Thirumurthy
T
D000284:Administration, Oral; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D009877:Endophthalmitis / Q000378:metabolism*; D005260:Female; D024841:Fluoroquinolones / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D000077734:Gatifloxacin; D006801:Humans; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D013997:Time Factors; D014822:Vitreous Body / Q000378:metabolism*
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D000077734:Gatifloxacin