Lysozyme in tears during post-operative inflammation of the eye

Lysozyme (ly) concentration in tears was measured the day before and the days following intracapsular cataract extraction in 25 patients. A median ly concentration of 1.30 mg/ml was found pre-operatively. On the first post-operative day a significant drop in the median ly concentration was observed (0.58 mg/ml). Thereafter a gradual rise towards pre-operative level was found at the 12th post-operative day. An inverse correlation existed between ly concentrations and Schirmer values during the observation period, and dilution thus seems to be an important cause of the post-operative drop in ly concentration. We observed an inverse relationship between ly level, and the number (%) of patients displaying bacterial colonization of the conjunctival sac 24 h later. The most frequently isolated bacteria were staphylococcus albus and diphteroids. It is proposed that the drop in ly concentration post-operatively may contribute to an increased risk of bacterial colonization of the eye post-operatively.