98th Annual Meeting DOG 2000

K 38

Bacterial keratitis in patients with and without history of contact lens wear

U. E. K. Schnurrbusch, V. Schön

Purpose: The study shows differences between contact lenses wearers and patients without history of contact lenses regarding the spectrum of ethiogical aggents and histomorphological findings in keratitis. Based on histological and microbioplogical analysis, there are given recommendations for an optimal initial antibiotic treatment in both groups.

Methods: From 1991 to 1999 smeears, scrapings and corneal biopsies were taken from 229 patients with keratitis. 142 patients of them have had a hitory of contact lens wear. The causing pathogens were isolated on directly inoculated culture media and identified by staning and microscopy. The resistance pattern was analysed for different antibiotics.

Results: The most frequently isolated germs were Staphylococcus spp.(62%), Streptococcus spp.(10%) and Pseudomonas aeruginosa (6%). Whereas sensitive gram-positive germs were predominating in contact lens wearers as well as in non-contact lens wearers. Multiresistant gram-negative germs could nearly exclusively be isolated from contact lens wearers. Frequently administered antibiotics like aminoglycosides and quinolones are effective in infections caused by Staphylococcus spp., but increasing resistance could be seen to Streptococcus spp. In this case, erythromycin is very sensitive. Gram-negative germs like Pseudomonas aeruginosa are sensitive to quinolones and some aminoglycosides.

Conclusions: In contact lens wearers more aggressive germs have to be considered than in non-contact lens wearers. In such cases, frequently administered antibiotics like aminoglykosides are not effective. To cover problematic gram negative germs we recommend the application of quinolones alternating with erythrmycin. The latter one is more effective than quinolones and aminoglycosides in case of Streptococcuc spp. co-involvement.

Klinik und Poliklinik für Augenheilkunde der Universität Leipzig, Liebigstr. 10-14, Leipzig