Serratia keratitis transmitted by contaminated eyedroppers.

Serratia marcescens keratitis developed in three patients after keratoplasty. Two patients were using prednisolone sodium phosphate eyedrops and the third was using 0.5% timolol maleate eyedrops. All three cases resolved after treatment with topically and subconjunctivally administered antibiotics. Although S. marcescens was isolated from the outer grooves of the bottletops and from the inner surfaces of the eyedropper caps, it was not cultured from the solutions in the bottles. Moisture collecting in the dead space between the cap and bottle was apparently a culture medium for Serratia. When eyedrops were expressed into the patient's eyes, the eyes were inoculated with Serratia from the contaminated liquid flowing down the eyedropper shaft.