Comparison of a point of care diagnostic test with a laboratory-based quantitative test for detection of MMP-9 in dry eye disease

Session Details

Session Title: Cornea: Medical

Session Date/Time: Tuesday 10/10/2017 | 08:00-10:30

Paper Time: 09:30

Venue: Room 3.6

First Author: : A.Garg INDIA

Co Author(s): :    R. Shetty   A. Ghosh   R. Shroff              

Abstract Details

Purpose:

To test the validity of a point-of-care rapid diagnostic test for detection of matrix metalloproteinase-9 (MMP-9) in the tears in comparison to the ELISA based laboratory test as a biomarker for Dry Eye Disease (DED)

Setting:

Cornea and Refractive Surgery Department at Narayana Nethralaya, Bangalore, Karnataka, India.

Methods:

In a prospective, sequential clinical study, the Inflammadry test was done in the out-patient department of a tertiary care hospital on fresh tears from 37 inflammatory DED subjects. Additional Schirmer's test strips were collected, test lengths were noted and stored in -80°C for subsequent testing. Protein was extracted from the frozen Schirmer's strips and subjected to ELISA testing using an MMP-9 (BioTrak assay, GE Healthcare, Pittsburgh, PA) ELISA assay kit (Quantikine Assay, R&D Systems, Minneapolis, MN) as per manufacturer’s instructions. For the ELISA Assay, 16 non DED control tears were also measured for benchmarking.

Results:

Of the 25 subjects who were inflammadry test negative, 4 showed MMP9 levels >40ng/mL by ELISA. The subjects positive for Inflammadry test (8 subjects) are not necessarily high (<40 ng/ml) in the ELISA test group, which could be due to the prolonged storage time of Schirmer's strips leading to degradation of analytes over time.

Conclusions:

The rapid point-of-care test for MMP-9 detection may not identify clinically relevant levels of MMP-9 in some subjects. Such false negative readouts can impact DED treatment planning. Hence treatment should not be based solely on the rapid point-of-care test for MMP-9 in DED.

Financial Disclosure:

NONE