Tear protein analysis in presumed congenital alacrima

Abstract

Objectives: It is often hard to reach a definitive diagnosis of congenital alacrima because of the difficultly in proving the lack of lacrimal tissue. We report here the distinct tear protein profile in presumed congenital alacrima.

Patients and methods: A 13-year-old girl with presumed congenital alacrima and 15 healthy volunteers aged 23-35 years were included in this study. Tears were collected using Schirmer strips, and tear protein analyses were performed. Tear samples were collected from the patient with alacrima before and after surgical punctal occlusion of both the upper and lower puncta, and tear protein extract was fractionated using HPLC. Lactoferrin and albumin concentrations in the tears were separately determined using ELISA.

Results: The chromatogram in the patient greatly differed from that in normal subjects with low concentrations of secretory IgA, lipocalin-1, and lysozyme. ELISA results indicated that the tear fluid in the patient contained a high concentration of albumin but a minimal concentration of lactoferrin. Punctal occlusion improved the ocular surface findings, but major lacrimal protein concentrations remained low and tear albumin concentrations further increased.

Conclusion: The tear protein profile of a patient with presumed congenital alacrima greatly differed from that of normal subjects. Tear protein analysis may be useful in making a diagnosis of congenital alacrima and in assessing the efficacy and mechanism of punctal occlusion.

Keywords: alacrima; albumin; dry eye; lactoferrin; tears.

Figure 1

Typical HPLC of tear proteins. Notes: Tear components normally include sIgA (1), lactoferrin and albumin (2), lipocalin-1 (3), and lysozyme (4). The HPLC chromatogram of the patient (A) greatly differed from that of the controls (B). Abbreviation: UV, ultraviolet.