Abstract
Abstract: :
Purpose: The use of intravitreal injections of triamcinolone has become widespread in recent years. One of the problems appears to be the development of hypopyon or a pseudo endophthalmitis shortly after administration. In this report, we describe the determination of endotoxin levels from a vial of commercially available triamcinolone acetonide used on a patient who developed such a hypopyon. Methods: A 72 year-old male underwent injection of 0.1cc(4 mg) triamcinolone acetonide for chronic CME with vision of count fingers. 48 hours after injection the patient’s vision had decreased to hand motion and he was found to have marked AC and vitreous cell with a small hypopyon, prominent vitreous haze and debris. He underwent vitreous tap with injection of vancomycin and ceftazidime. 14 days after the injection the vitreous and anterior chamber inflammation had completely cleared. The endotoxin level of triamcinolone aceontide was assayed via the gel-clot method (as a limits test with comparison to the maximum allowed FDA limit, as stated in appendix E of the Endotoxin Guidance). Results: Cultures were negative. Determination of endotoxin in triamcinolone acetonide showed a concentration of less than 0.03 EU/ml at a 1:100 dilution of the suspension equaling a level of 3.0 EU/ml of the final product. Conclusions: The patient may have had endophthalmitis. The FDA’s specification for maximum endotoxin level in 4.39 EU/ml and the triamcinolone acetonide assayed was well below this level, however this specification is based on 5 EU as the maximum safe endotoxin exposure for a 70kg individual. This suggests a safe systemic exposure to be approximately 0.001 EU/ml. For an intraocular injection, where it can be expected that the endotoxin will not be distributed throughout the body, 0.1ml of triamcinolone acetonide as tested here would result in an intravitreal endotoxin concentration of approximately 0.1 EU/ml, which may cause a problem. There are no FDA guidelines concerning the maximum endotoxin level for an intraocular dose of triamcinolone and it is possible that while 4.39EU/ml is appropriate for general use, this level may, in the absence of guidance from the FDA, be too high for an intraocular injection.
Keywords: vitreous • endophthalmitis